Family history and gastric cancer incidence and mortality in Asia: a pooled analysis of more than half a million participants

BACKGROUND

The family history of gastric cancer holds important implications for cancer surveillance and prevention, yet existing evidence predominantly comes from case-control studies. We aimed to investigate the association between family history of gastric cancer and gastric cancer risk overall and by various subtypes in Asians in a prospective study.

METHODS

We included 12 prospective cohorts with 550,508 participants in the Asia Cohort Consortium. Cox proportional hazard regression was used to estimate study-specific adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between family history of gastric cancer and gastric cancer incidence and mortality, then pooled using random-effects meta-analyses. Stratified analyses were performed for the anatomical subsites and histological subtypes.

RESULTS

During the mean follow-up of 15.6 years, 2258 incident gastric cancers and 5194 gastric cancer deaths occurred. The risk of incident gastric cancer was higher in individuals with a family history of gastric cancer (HR 1.44, 95% CI 1.32-1.58), similarly in males (1.44, 1.31-1.59) and females (1.45, 1.23-1.70). Family history of gastric cancer was associated with both cardia (HR 1.26, 95% CI 1.00-1.60) and non-cardia subsites (1.49, 1.35-1.65), and with intestinal- (1.48, 1.30-1.70) and diffuse-type (1.59, 1.35-1.87) gastric cancer incidence. Positive associations were also found for gastric cancer mortality (HR 1.30, 95% CI 1.19-1.41).

CONCLUSIONS

In this largest prospective study to date on family history and gastric cancer, a familial background of gastric cancer increased the risk of gastric cancer in the Asian population. Targeted education, screening, and intervention in these high-risk groups may reduce the burden of gastric cancer.

Obesity is associated with biliary tract cancer mortality and incidence: A pooled analysis of 21 cohort studies in the Asia Cohort Consortium

Body fatness is considered a probable risk factor for biliary tract cancer (BTC), whereas cholelithiasis is an established factor. Nevertheless, although obesity is an established risk factor for cholelithiasis, previous studies of the association of body mass index (BMI) and BTC did not take the effect of cholelithiasis fully into account. To better understand the effect of BMI on BTC, we conducted a pooled analysis using population-based cohort studies in Asians. In total, 905 530 subjects from 21 cohort studies participating in the Asia Cohort Consortium were included. BMI was categorized into four groups: underweight (<18.5 kg/m2 ); normal (18.5-22.9 kg/m2 ); overweight (23-24.9 kg/m2 ); and obese (25+ kg/m2 ). The association between BMI and BTC incidence and mortality was assessed using hazard ratios (HR) and 95% confidence intervals (CIs) by Cox regression models with shared frailty. Mediation analysis was used to decompose the association into a direct and an indirect (mediated) effect. Compared to normal BMI, high BMI was associated with BTC mortality (HR 1.19 [CI 1.02-1.38] for males, HR 1.30 [1.14-1.49] for females). Cholelithiasis had significant interaction with BMI on BTC risk. BMI was associated with BTC risk directly and through cholelithiasis in females, whereas the association was unclear in males. When cholelithiasis was present, BMI was not associated with BTC death in either males or females. BMI was associated with BTC death among females without cholelithiasis. This study suggests BMI is associated with BTC mortality in Asians. Cholelithiasis appears to contribute to the association; and moreover, obesity appears to increase BTC risk without cholelithiasis.

Lung Cancer Risk Prediction Models for Asian Ever-Smokers

INTRODUCTION

Although lung cancer prediction models are widely used to support risk-based screening, their performance outside Western populations remains uncertain. This study aims to evaluate the performance of 11 existing risk prediction models in multiple Asian populations and to refit prediction models for Asians.

METHODS

In a pooled analysis of 186,458 Asian ever-smokers from 19 prospective cohorts, we assessed calibration (expected-to-observed ratio) and discrimination (area under the receiver operating characteristic curve [AUC]) for each model. In addition, we developed the "Shanghai models" to better refine risk models for Asians on the basis of two well-characterized population-based prospective cohorts and externally validated them in other Asian cohorts.

RESULTS

Among the 11 models, the Lung Cancer Death Risk Assessment Tool yielded the highest AUC (AUC [95% confidence interval (CI)] = 0.71 [0.67-0.74] for lung cancer death and 0.69 [0.67-0.72] for lung cancer incidence) and the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Model had good calibration overall (expected-to-observed ratio [95% CI] = 1.06 [0.90-1.25]). Nevertheless, these models substantially underestimated lung cancer risk among Asians who reported less than 10 smoking pack-years or stopped smoking more than or equal to 20 years ago. The Shanghai models were found to have marginal improvement overall in discrimination (AUC [95% CI] = 0.72 [0.69-0.74] for lung cancer death and 0.70 [0.67-0.72] for lung cancer incidence) but consistently outperformed the selected Western models among low-intensity smokers and long-term quitters.

CONCLUSIONS

The Shanghai models had comparable performance overall to the best existing models, but they improved much in predicting the lung cancer risk of low-intensity smokers and long-term quitters in Asia.

Association of Marital Status With Total and Cause-Specific Mortality in Asia

IMPORTANCE

Marital status has been shown to be associated with mortality, but evidence in Asian populations is limited.

OBJECTIVE

To examine the association of marital status with total and cause-specific mortality.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included individual participant data from 16 prospective studies in the Asia Cohort Consortium conducted between 1963 and 2015. Asian participants with complete information on marital and vital status were included. Study-specific hazard ratios (HRs) and 95% CIs were estimated using Cox proportional hazards model and then pooled using a random-effects meta-analysis. The analysis began in February 2021 and ended in August 2021.

EXPOSURES

Marital status.

MAIN OUTCOMES AND MEASURES

All-cause and cause-specific mortality.

RESULTS

Of 623 140 participants (326 397 women [52.4%] and 296 743 men [47.6%]; mean [SD] age, 53.7 [10.2] years; mean [SD] follow-up time, 15.5 [6.1] years), 123 264 deaths were ascertained. Compared with married individuals, those who were unmarried had pooled HRs of 1.15 (95% CI, 1.07-1.24) for total mortality, 1.12 (95% CI, 1.03-1.22) for cerebrovascular disease mortality, 1.20 (95% CI, 1.09-1.31) for coronary heart disease mortality, 1.17 (95% CI, 1.07-1.28) for circulatory system diseases mortality, 1.06 (95% CI, 1.01-1.11) for cancer mortality, 1.14 (95% CI, 1.05-1.23) for respiratory diseases mortality, and 1.19 (95% CI, 1.05-1.34) for external causes of death. Positive associations with total mortality were also observed for those who were single (HR, 1.62; 95% CI, 1.41-1.86), separated (HR, 1.35; 95% CI, 1.13-1.61), divorced (HR, 1.38; 95% CI, 1.13-1.69), and widowed (HR, 1.09; 95% CI, 1.04-1.13). In subgroup analyses, the positive association persisted across baseline health conditions, and the risk of death was more pronounced among men or people younger than 65 years.

CONCLUSIONS AND RELEVANCE

This large pooled cohort study of individual participant data provides strong evidence that being unmarried, as well as belonging to the unmarried subcategories, was positively associated with total and cause-specific mortality. Investment of targeted social support services might need to be considered in light of the mortality differences between married and unmarried individuals.

Comparing warning signs of suicide between suicide decedents with depression and those non-diagnosed psychiatric disorders

OBJECTIVE

Early recognition of a high-risk group impending suicide is important. We aimed to compare warning signs depending on the nature of the psychiatric disorder and whether it was a documented diagnosis.

METHODS

Data of suicide decedents were collected from police records from 2013 to 2017. We evaluate psychiatric symptoms and warning signs in three aspects (language, behavior, and affect) using the Korea-Psychological Autopsy Checklist for Police Records (K-PAC-PR).

RESULTS

A total of 13,265 suicide decedents were recruited for this study. Of them, 66.9% of females and 46.7% of males diagnosed psychiatric disorders, with depressive disorder being the most common one. Warning signs were observed in 93.0% of suicide decedents. They were observed more in those who were diagnosed with psychiatric disorders, especially in those with a depressive disorder. "Talking about dying or suicide" was the most common warning sign in all groups, and "apathetic behavior" was the most related warning sign for depressive disorder. Especially for "talking about dying or suicide," the proportion of observed "within a week" was high, making it valuable as a warning sign.

CONCLUSION

Warning signs were commonly found in suicide decedents regardless of gender. They were more common among the decedents diagnosed with psychiatric disorders, especially among those with a depressive disorder.

Psychological autopsy study comparing suicide decedents with and without a history of suicide attempts in a nationwide sample of South Korea

The majority of suicide decedents die on their initial attempt. To bring attention to suicide decedents without a suicide attempt history, the current study explored their demographic, clinical, and suicide-related characteristics. The data were derived from the Korea National Investigation of Suicide Victims Study, which assessed all suicide cases from 2013 to 2017 recorded in police investigation reports. We compared suicide decedents with and without a history of nonfatal attempts using the Korea Psychological Autopsy Checklist for Police Records (K-PAC). Out of 5228 cases included in our study, 3147 (60.2%) died on their first suicide attempt. Demographically, those who were male, older than 65, employed, and married/widowed were more likely to die on their initial attempt. Clinically, those who died on their initial attempt were more likely to have never been diagnosed with psychiatric disorders, whereas those who died on a repeated attempt were more likely to have been diagnosed with mood disorders. In terms of suicide-related factors, experiencing relationship problems and complaining about physical discomfort were associated with dying on an initial attempt. Depressed affect, self-harming behaviors, and talking about suicide or death were associated with repeated attempts.

Association between body mass index and oesophageal cancer mortality: a pooled analysis of prospective cohort studies with >800 000 individuals in the Asia Cohort Consortium

BACKGROUND

The association between body mass index (BMI) and oesophageal cancer (OC) has been consistently negative among Asians, whereas different associations based on histological OC subtypes have been observed in Europeans and North Americans. We examined the association between BMI and OC mortality in the Asia Cohort Consortium.

METHODS

We performed a pooled analysis to evaluate the association between BMI and OC mortality among 842 630 Asians from 18 cohort studies. Cox regression models were used to estimate hazard ratios (HRs) and 95% CIs.

RESULTS

A wide J-shaped association between BMI and overall OC mortality was observed. The OC mortality risk was increased for underweight (BMI <18.5 kg/m2: HR = 2.20, 95% CI 1.80-2.70) and extreme obesity (BMI ≥35 kg/m2: HR = 4.38, 95% CI 2.25-8.52) relative to the reference BMI (23-25 kg/m2). This association pattern was confirmed by several alternative analyses based on OC incidence and meta-analysis. A similar wide J-shaped association was observed in oesophageal squamous cell carcinoma (OSCC). Smoking and alcohol synergistically increased the OC mortality risk in underweight participants (HR = 6.96, 95% CI 4.54-10.67) relative to that in reference BMI participants not exposed to smoking and alcohol.

CONCLUSION

Extreme obesity and being underweight were associated with an OC mortality risk among Asians. OC mortality and BMI formed a wide J-shaped association mirrored by OSCC mortality. Although the effect of BMI on OSCC and oesophageal adenocarcinoma mortality can be different in Asians, further research based on a large case-control study is recommended.

Association of Fasting Glucose and Glycated Hemoglobin with Vitamin D Level According to Diabetes Mellitus Status in Korean Adults

Objectives

Previous studies have suggested that vitamin D deficiency might increase the risk of type 2 diabetes mellitus(DM). However, few studies have examined whether vitamin D continues to affect glucose control after DM diagnosis. Therefore, we examined the association between vitamin D and glucose in nondiabetics and DM patients.

Methods

We analyzed data for 32,943 adults aged 19 years and older from the 2008 to 2014 Korea National Health and Nutrition Examination Survey. Vitamin D levels were determined using the 25-hydroxyvitamin D concentration, and patients were grouped into one of three categories according to those results DM was defined as a fasting glucose level ≥ 126 mg/dL, current use of DM medications or insulin injections, or a self-reported diagnosis of DM by a doctor.

Results

In male DM patients, hemoglobin A1c(HbA1c) level increased significantly as vitamin D levels became severely deficient. Among the abnormal HbA1c subgroups of males and postmenopausal females, HbA1c levels were significantly higher in the severe vitamin D deficiency subgroup (p for trend = 0.0044 and 0.0219 for males and postmenopausal females, respectively). There were significant differences between abnormal HbA1c subgroups and normal HbA1c subgroups in both males and females. Regardless of sex or menopause status, however, there was no significant association between vitamin D and fasting glucose in fasting glucose subgroups.

Conclusion

Males and females in the abnormal HbA1c subgroups showed markedly elevated blood glucose when they also had vitamin D deficiency. Furthermore, there was a more distinct difference in the HbA1c subgroups than in the fasting glucose subgroups.

Early psychiatric referral after attempted suicide helps prevent suicide reattempts: A longitudinal national cohort study in South Korea

INTRODUCTION

Although people who attempted suicide tend to repeat suicide attempts, there is a lack of evidence on the association between psychiatric service factors and suicide reattempt among them.

METHODS

We used a nationwide, population-based medical record database of South Korea to investigate the use of psychiatric services before and after the index suicide attempt and the association between psychiatric service factors after the index suicide attempt with the risk of suicide reattempt.

RESULTS

Among 5,874 people who had attempted suicide, the all-cause mortality within 3 months after the suicide attempt was 11.6%. Among all subjects who attempted suicide, 30.6% of them had used psychiatric services within 6 months before the suicide attempt; 43.7% of them had used psychiatric services within 3 months after the suicide attempt. Among individuals who had visited clinics following attempted suicide, the cumulative incidence of suicide reattempt over a mean follow-up period of 5.1 years was 3.4%. About half of suicide reattempts occurred within 1 year after the index suicide attempt. Referral to psychiatric services within 7 days was associated with a decreased risk of suicide reattempt (adjusted hazard ratio, 0.51; 95% confidence intervals, 0.29-0.89).

CONCLUSION

An early psychiatric referral within 1 week after a suicide attempt was associated with a decreased risk of suicide reattempt.

Coffee and tea consumption and mortality from all causes, cardiovascular disease and cancer: a pooled analysis of prospective studies from the Asia Cohort Consortium

BACKGROUND

Accumulating evidence suggests that consuming coffee may lower the risk of death, but evidence regarding tea consumption in Asians is limited. We examined the association between coffee and tea consumption and mortality in Asian populations.

METHODS

We used data from 12 prospective cohort studies including 248 050 men and 280 454 women from the Asia Cohort Consortium conducted in China, Japan, Korea and Singapore. We estimated the study-specific association of coffee, green tea and black tea consumption with mortality using Cox proportional-hazards regression models and the pooled study-specific hazard ratios (HRs) using a random-effects model.

RESULTS

In total, 94 744 deaths were identified during the follow-up, which ranged from an average of 6.5 to 22.7 years. Compared with coffee non-drinkers, men and women who drank at least five cups of coffee per day had a 24% [95% confidence interval (CI) 17%, 29%] and a 28% (95% CI 19%, 37%) lower risk of all-cause mortality, respectively. Similarly, we found inverse associations for coffee consumption with cardiovascular disease (CVD)-specific and cancer-specific mortality among both men and women. Green tea consumption was associated with lower risk of mortality from all causes, CVD and other causes but not from cancer. The association of drinking green tea with CVD-specific mortality was particularly strong, with HRs (95% CIs) of 0.79 (0.68, 0.91) for men and 0.78 (0.68, 0.90) for women who drank at least five cups per day of green tea compared with non-drinkers. The association between black tea consumption and mortality was weak, with no clear trends noted across the categories of consumption.

CONCLUSIONS

In Asian populations, coffee consumption is associated with a lower risk of death overall and with lower risks of death from CVD and cancer. Green tea consumption is associated with lower risks of death from all causes and CVD.

Increased risk of depression before and after unilateral or bilateral oophorectomy: A self-controlled case series study using a nationwide cohort in South Korea

BACKGROUND

There is insufficient evidence of the association between oophorectomy and depression.

METHODS

A nationwide medical records database of South Korea was used to investigate incidence rate ratios (IRRs) of major depressive disorder before and after oophorectomy (n = 36,284) using a self-controlled case series design. Outcomes before and after hysterectomy (n = 25,415) were identified to compare with those around oophorectomy.

RESULTS

In all oophorectomy and hysterectomy groups, the risk of depression was increased before and after surgery, peaking immediately before or after the operation, with no significant difference in the pattern of the results according to type of surgery. In the bilateral oophorectomy group, the IRR was increased between 2-3 months before the surgery, peaking immediately before surgery at 1.39 (95% CI: 1.30-1.49, p < .0001), and remained heightened for one-year postexposure. Subgroup analyses performed according to ovarian cancer, age group, and hormone replacement therapy produced results similar to those of the main outcome.

LIMITATIONS

Because we used claims data, the detailed clinical information related to oophorectomy is lacking. There is possibility that time-varying confounder besides age and season might have affected the results CONCLUSIONS: The risk of depression increased before and after oophorectomy. The increase in risk of depression started before oophorectomy and peaked immediately before or after the operation, but no significant differences between unilateral and bilateral surgery and cancer and noncancer or among age groups were noted.

Risks of suicide attempts after prescription of zolpidem in people with depression: a nationwide population study in South Korea

OBJECTIVES

To investigate the association between zolpidem prescription and suicide attempts in people with depression.

METHODS

A nationwide, population-based electronic medical records database from the Health Insurance Review & Assessment Service of South was used to investigate the incidence rate ratios (IRRs) of suicide attempts and probable suicide attempts in people with depression before and after zolpidem prescription using self-controlled case series design.

RESULTS

In a total of 445 people who attempted suicide and 23 141 people who attempted probable suicide attempt, the IRRs of suicidal behavior during the risk periods before and after zolpidem prescription increased compared with those at the baseline. The IRRs gradually increased and peaked immediately before the prescription of zolpidem. The IRR was 70.06 (95% CI: 25.58-191.90) on day 2 before zolpidem prescription and 63.35 (95% CI: 22.99-174.59) on day 1 after zolpidem prescription in the suicide attempt group. The IRR was 24.07 (95% CI: 20.50-28.26) on the day before zolpidem prescription and 14.96 (95% CI: 12.21-18.34) on the day after zolpidem prescription in the probable suicide attempt group. The ratios declined eventually after zolpidem was prescribed.

CONCLUSIONS

Although zolpidem prescription was associated with an increased risk of suicide attempts in people with depression, the risk increased and peaked immediately before zolpidem prescription. The risk declined gradually thereafter. This result indicates that the risk of suicide attempts increases at the time of zolpidem prescription. However, zolpidem prescription does not contribute to additional increase in the risk of suicide attempts.

Predictive Factors Associated With Methods of Suicide: The Korean National Investigations of Suicide Victims (The KNIGHTS Study)

Background: Because the suicide mortality depends on the lethality of suicide methods, the identification and prediction of suicide methods are important for suicide prevention. Methods: Examination data of suicide decedents were collected based on police reports. Suicide decedents were divided into groups according to the suicide methods (hanging, gas poisoning, pesticide poisoning, jumping, drug poisoning, and drowning) they used. Predictive factors for each suicide method in comparison to other suicide methods were identified. Results: Among 23,647 subjects, hanging was the most common method of suicide. Regarding gas poisoning, the history of previous suicide attempt was a risk factor and being age of 65 or older was a protective factor. Being age of 65 or older showed a highly strong association with suicide by pesticide poisoning. Being age of 18 or younger and the presence of schizophrenia were associated with jumping. A history of psychiatric outpatient treatment was a risk factor for drug poisoning. Regarding suicide by drowning, schizophrenia was a risk factor, while being age of 65 or older was a protective factor. Limitations: Only eight out of a total of 17 regions in South Korea were examined and included in the data of this study. Also, the methods of suicide were defined as one method that directly caused the death, which could undermine other less fatal methods used. Conclusions: There were differences in predictive factors according to the method of suicide. Predicting the method of suicide in people at high risk for suicide stands to be an important strategy for suicide prevention in clinical settings.

Risk of Suicide Attempt after Thyroidectomy: A Nationwide Population Study in South Korea

OBJECTIVE

To investigate the association between thyroidectomy and suicide attempt.

METHODS

A nationwide population-based electronic medical records database of South Korea between January 1, 2009 and June 30, 2016 was used to investigate incidence rate ratios (IRRs) of suicide attempts and probable suicide attempts before and after thyroidectomy using a self-controlled case series design.

RESULTS

In 2,986 patients who attempted suicide or probable suicide, the IRRs of suicidal behaviors during risk periods one year before and after thyroidectomy were investigated. Generally, after thyroidectomy, there was no increase in IRR compared to the non-risk period. When data were analyzed according to thyroidectomy type, after partial thyroidectomy, IRR increased up to 1.43 (95% CI: 1.03-1.98, p=0.032) in the days 91-181 period. In the subgroup with major depressive disorder (MDD), the IRR increased up to 1.74 (95% CI: 1.21-2.51, p=0.003) before thyroidectomy, and increased up to 1.67 (95% CI: 1.16-2.41, p=0.006) after thyroidectomy.

CONCLUSION

Although the general risk of suicide attempt was not increased after thyroidectomy, patients with MDD showed increased risk of suicide attempt before and after thyroidectomy. These results suggest that suicidality should be evaluated when depressive symptoms are present in patients who have undergone thyroidectomy.

Quantifying the association of low-intensity and late initiation of tobacco smoking with total and cause-specific mortality in Asia

BACKGROUND

Little is known about the health harms associated with low-intensity smoking in Asians who, on average, smoke fewer cigarettes and start smoking at a later age than their Western counterparts.

METHODS

In this pooled analysis of 738 013 Asians from 16 prospective cohorts, we quantified the associations of low-intensity (<5 cigarettes/day) and late initiation (≥35 years) of smoking with mortality outcomes. HRs and 95% CIs were estimated for each cohort by Cox regression. Cohort-specific HRs were pooled using random-effects meta-analysis.

FINDINGS

During a mean follow-up of 11.3 years, 92 068 deaths were ascertained. Compared with never smokers, current smokers who consumed <5 cigarettes/day or started smoking after age 35 years had a 16%-41% increased risk of all-cause, cardiovascular disease (CVD), respiratory disease mortality and a >twofold risk of lung cancer mortality. Furthermore, current smokers who started smoking after age 35 and smoked <5 cigarettes/day had significantly elevated risks of all-cause (HRs (95% CIs)=1.14 (1.05 to 1.23)), CVD (1.27 (1.08 to 1.49)) and respiratory disease (1.54 (1.17 to 2.01)) mortality. Even smokers who smoked <5 cigarettes/day but quit smoking before the age of 45 years had a 16% elevated risk of all-cause mortality; however, the risk declined further with increasing duration of abstinence.

CONCLUSIONS

Our study showed that smokers who smoked a small number of cigarettes or started smoking later in life also experienced significantly elevated all-cause and major cause-specific mortality but benefited from cessation. There is no safe way to smoke-not smoking is always the best choice.

Predictive factors of diagnostic conversion from major depressive disorder to bipolar disorder in young adults ages 19-34: A nationwide population study in South Korea

BACKGROUND

Predicting patients who convert to bipolar disorder is important for deciding appropriate treatment for young adults with major depressive disorder (MDD). We focused on the predictive factors of bipolar conversion in a large population of young adults.

METHODS

A nationwide, population-based electronic medical records database from the Health Insurance Review & Assessment service of South was used to investigate adjusted hazard ratio (HR) of each potential predictor of the bipolar converter group compared to the non-converter group using Cox regression analysis including age of onset, medication use, clinical features, comorbid disorders, admission, self-harm, and negative life events in childhood.

RESULTS

Among 291,721 subjects who were initially diagnosed with MDD in young adults, 12,376 subjects experienced diagnostic conversion to bipolar disorder. The cumulative incidence was 6.46% during the average 3.26 years of follow-up. Among the predictive factors during diagnosis of MDD, antipsychotic use (HR 3.12, 95%CI, 2.99-3.26, p < 0.0001) and mood stabilizers (HR 2.45, 95%CI, 2.35-2.55, p < 0.0001) showed the strongest association with diagnostic conversion to bipolar disorder. In addition, female sex, younger age of onset, mood stabilizer use, recurrent depression, psychotic symptoms, and admission to a psychiatric ward during diagnosis of MDD were also associated with diagnostic conversion to bipolar disorder.

CONCLUSION

In young adults with MDD, antipsychotic and mood stabilizer use during diagnosis of MDD were the strongest predictive factors with diagnostic conversion to bipolar disorder during follow-up. If young adults with MDD need antipsychotics or mood stabilizer, patients should be carefully evaluated for possibility of bipolar disorder.

Increased Morbidity of Major Depressive Disorder After Thyroidectomy: A Nationwide Population-Based Study in South Korea

Background: The number of thyroidectomies in South Korea has been increasing rapidly due to extensive checkups for thyroid cancer. However, few studies have examined the association between thyroidectomy and major depressive disorder (MDD). We investigated the association between thyroidectomy and the risk of MDD. Methods: A population-based electronic medical records database from South Korea was used to identify 187,176 individuals who underwent partial or total thyroidectomy between 2009 and 2016. A self-controlled case series design and Cox regression analyses were used to identify risk factors for MDD. Results: Among the 187,176 individuals who underwent thyroidectomy, 16,744 (8.9%) were diagnosed with MDD during the observation period. Of those, 3837 (22.9%) underwent partial thyroidectomy and 12,907 (77.1%) underwent total thyroidectomy. An elevated MDD risk was found during the one-year period before thyroidectomy, with incidence rate ratios (IRRs) of 1.29 ([95% confidence interval [CI] 1.18-1.41], p < 0.0001) for subjects with partial thyroidectomy and 1.27 ([95% CI 1.21-1.33], p < 0.0001) for subjects with total thyroidectomy. After total thyroidectomy, the IRR increased for 31-60 days (IRR 1.81; [95% CI 1.59-2.06], p < 0.0001) and remained elevated for up to 540 days, whereas after partial thyroidectomy, the IRR increased for 31-60 days (IRR 1.68; [95% CI 1.32-2.13], p < 0.0001) but returned to baseline levels after 270 days. Total thyroidectomy was associated with a prolonged risk of MDD compared with partial thyroidectomy in patients with cancer, which was different from the results in patients without cancer. Conclusion: The incidence of MDD increased in the period immediately after thyroidectomy and remained high for one to two years. This study highlights the importance of relatively long-term regular psychiatric assessments in patients who undergo partial or total thyroidectomy.

Gastric Complications after Adjuvant Radiotherapy for Breast Cancer

Purpose

In some patients who receive adjuvant radiotherapy (RT) for the left breast, the stomach is located inside the RT field. This study investigates the incidence of gastric complications following adjuvant RT for breast cancer using data of the Health Insurance Review and Assessment Service in South Korea.

Methods

We identified 37,966 women who underwent surgery and received adjuvant RT for breast cancer. The cumulative incidence rate of gastric hemorrhage and gastric cancer was calculated and compared for left and right breast cancers.

Results

Among 37,966 patients, 19,531 (51.4%) and 18,435 (48.6%) had right and left breast cancers, respectively. After a median follow-up duration of 6.3 years, the cumulative incidence of gastric cancer and gastric hemorrhage did not differ between right and left breast cancers (p = 0.414 and p = 0.166, respectively). The multivariable analysis revealed that old age was the only factor associated with the development of gastric cancer (p < 0.001) and gastric hemorrhage (p < 0.001). The incidence of gastric cancer and hemorrhage did not differ between patients who received adjuvant RT for right and left breast cancers.

Conclusion

Irradiation-related chronic complications of the stomach in patients with breast cancer are minimal. A study with a longer follow-up duration might be needed to assess the risk of gastric cancer.

Menopausal hormone therapy and mild cognitive impairment: a randomized, placebo-controlled trial

OBJECTIVE

The aim of the study was to explore the therapeutic potential of menopausal hormone therapy (MHT) in women with mild cognitive impairment (MCI).

METHODS

Thirty-seven postmenopausal women (age range: 57-82 y) with multiple-domain, amnestic subtype MCI were randomly assigned to either placebo (n = 18) or MHT (n = 19) for 24 months (percutaneous estradiol [E2] gel [0.1%, 2 mg/d] and oral micronized progesterone [MP4] [100 mg/d]). All participants received donepezil, and apolipoprotein E genotype was determined. The primary endpoint was general cognitive function: Alzheimer's disease Assessment Scale, cognitive subscale, the Korean version of Mini-Mental State Examination (K-MMSE), and the Korean version of the Montreal Cognitive Assessment (MoCA_K) were performed in-person every 6 months.

RESULTS

Twenty-one participants (placebo 13, MHT 8) completed the trial (56.8%). Progression rates to dementia were 52.9% (9/17) in the placebo group and 44.4% (8/18) in the MHT group. Within-group analysis showed that all three tests significantly worsened during the trial in the placebo, but not the MHT groups. Analysis adjusted for ε4 allele demonstrated that MHT significantly reduced deterioration of MoCA_K score, a sensitive tool for assessing global cognition in MCI (P = 0.0261). Compared with the control group, both MoCA_K (P = 0.043; mean difference, 3.85; 95% CI, -0.46 to 8.16) and K-MMSE (P = 0.0319; mean difference, 3.26; 95% CI, 0.04-6.48) scores were significantly better at 24 months in the MHT group.

CONCLUSIONS

Long-term MHT using percutaneous E2 gel and oral MP4 might attenuate cognitive decline in postmenopausal women with MCI.

Association between educational level and total and cause-specific mortality: a pooled analysis of over 694 000 individuals in the Asia Cohort Consortium

OBJECTIVE

To study the association of educational level and risk of death from all causes, cardiovascular disease (CVD) and cancer among Asian populations.

DESIGN

A pooled analysis of 15 population-based cohort studies.

SETTING AND PARTICIPANTS

694 434 Asian individuals from 15 prospective cohorts within the Asia Cohort Consortium.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

HRs and 95% CIs for all-cause mortality, as well as for CVD-specific mortality and cancer-specific mortality.

RESULTS

A total of 694 434 participants (mean age at baseline=53.2 years) were included in the analysis. During a mean follow-up period of 12.5 years, 103 023 deaths were observed, among which 33 939 were due to cancer and 34 645 were due to CVD. Higher educational levels were significantly associated with lower risk of death from all causes compared with a low educational level (≤primary education); HRs and 95% CIs for secondary education, trade/technical education and ≥university education were 0.88 (0.85 to 0.92), 0.81 (0.73 to 0.90) and 0.71 (0.63 to 0.80), respectively (ptrend=0.002). Similarly, HRs (95% CIs) were 0.93 (0.89 to 0.97), 0.86 (0.78 to 0.94) and 0.81 (0.73 to 0.89) for cancer death, and 0.88 (0.83 to 0.93), 0.77 (0.66 to 0.91) and 0.67 (0.58 to 0.77) for CVD death with increasing levels of education (both ptrend <0.01). The pattern of the association among East Asians and South Asians was similar compared with ≤primary education; HR (95% CI) for all-cause mortality associated with ≥university education was 0.72 (0.63 to 0.81) among 539 724 East Asians (Chinese, Japanese and Korean) and 0.61 (0.54 to 0.69) among 154 710 South Asians (Indians and Bangladeshis).

CONCLUSION

Higher educational level was associated with substantially lower risk of death among Asian populations.

Predictive value of plasma neutrophil gelatinase-associated lipocalin in acute charcoal-burning carbon monoxide poisoning

This study aimed to assess the feasibility of using the plasma neutrophil gelatinase-associated lipocalin (NGAL) level at the time of presentation in the emergency department (ED) to predict acute kidney injury (AKI) and the long-term neurological outcomes of acute charcoal-burning carbon monoxide (CO) poisoning. This retrospective study included 260 patients who suffered acute charcoal-burning CO poisoning. The median plasma NGAL concentration at the time of presentation in the ED after acute charcoal-burning CO poisoning was 78 (54–115) ng/ml. The NGAL level was an independent predictor of AKI development and could be used to stratify the severity of AKI. However, the area under the receiver operating characteristic curve (AUC) of the predictive model for AKI that included both the plasma NGAL level and clinical parameters was comparable to that of the predictive model including only the clinical parameters. The plasma NGAL level at the time of presentation in the ED was an independent factor predicting long-term neurological outcomes in patients who did not develop AKI. In these patients, the plasma NGAL level significantly improved the predictive accuracy of the model when used in combination with clinical parameters. In contrast, the plasma NGAL level was not associated with long-term neurological outcomes in patients who developed AKI. Measurement of the plasma NGAL level at the time ED presentation might improve the prediction of long-term neurological outcomes in patients who do not develop AKI after acute charcoal-burning CO poisoning. However, it might not offer additional benefit for AKI prediction compared to previously used markers.

Association of Diabetes With All-Cause and Cause-Specific Mortality in Asia: A Pooled Analysis of More Than 1 Million Participants

IMPORTANCE

Asia is home to the largest diabetic populations in the world. However, limited studies have quantified the association of diabetes with all-cause and cause-specific mortality in Asian populations.

OBJECTIVES

To evaluate the association of diabetes with all-cause and cause-specific mortality in Asia and to investigate potential effect modifications of the diabetes-mortality associations by participants' age, sex, education level, body mass index, and smoking status.

DESIGN, SETTING, AND PARTICIPANTS

This pooled analysis incorporated individual participant data from 22 prospective cohort studies of the Asia Cohort Consortium conducted between 1963 and 2006. A total of 1 002 551 Asian individuals (from mainland China, Japan, South Korea, Singapore, Taiwan, India, and Bangladesh) were followed up for more than 3 years. Cohort-specific hazard ratios and 95% confidence intervals for all-cause and cause-specific mortality were estimated using Cox regression models and then pooled using random-effects meta-analysis. Analysis was conducted between January 10, 2018, and August 31, 2018.

EXPOSURES

Doctor-diagnosed diabetes, age, sex, education level, body mass index, and smoking status.

MAIN OUTCOMES AND MEASURES

All-cause and cause-specific mortality.

RESULTS

Of 1 002 551 participants (518 537 [51.7%] female; median [range] age, 54.0 [30.0-98.0] years), 148 868 deaths were ascertained during a median (range) follow-up of 12.6 (3.0-38.9) years. The overall prevalence of diabetes reported at baseline was 4.8% for men and 3.6% for women. Patients with diabetes had a 1.89-fold risk of all-cause death compared with patients without diabetes (hazard ratio [HR], 1.89; 95% CI, 1.74-2.04), with the highest relative risk of death due to diabetes itself (HR, 22.8; 95% CI, 18.5-28.1), followed by renal disease (HR, 3.08; 95% CI, 2.50-3.78), coronary heart disease (HR, 2.57; 95% CI, 2.19-3.02), and ischemic stroke (HR, 2.15; 95% CI, 1.85-2.51). The adverse diabetes-mortality associations were more evident among women (HR, 2.09; 95% CI, 1.89-2.32) than among men (HR, 1.74; 95% CI, 1.62-1.88) (P for interaction < .001) and more evident among adults aged 30 to 49 years (HR, 2.43; 95% CI, 2.08-2.84) than among adults aged 70 years and older (HR, 1.51; 95% CI, 1.40-1.62) (P for interaction < .001). A similar pattern of association was found between diabetes and cause-specific mortality, with significant variations noted by sex and age.

CONCLUSIONS AND RELEVANCE

This study found that diabetes was associated with increased risk of death from several diseases among Asian populations. Development and implementation of diabetes management programs are urgently needed to reduce the burden of diabetes in Asia.

Tobacco Smoking and Mortality in Asia: A Pooled Meta-analysis

IMPORTANCE

Understanding birth cohort-specific tobacco smoking patterns and their association with total and cause-specific mortality is important for projecting future deaths due to tobacco smoking across Asian populations.

OBJECTIVES

To assess secular trends of tobacco smoking by countries or regions and birth cohorts and evaluate the consequent mortality in Asian populations.

DESIGN, SETTING, AND PARTICIPANTS

This pooled meta-analysis was based on individual participant data from 20 prospective cohort studies participating in the Asia Cohort Consortium. Between September 1, 2017, and March 31, 2018, a total of 1 002 258 Asian individuals 35 years or older were analyzed using Cox proportional hazards regression analysis and random-effects meta-analysis. The pooled results were presented for mainland China; Japan; Korea, Singapore, and Taiwan; and India.

EXPOSURES

Tobacco use status, age at starting smoking, number of cigarettes smoked per day, and age at quitting smoking.

MAIN OUTCOMES AND MEASURES

Country or region and birth cohort-specific mortality and the population attributable risk for deaths from all causes and from lung cancer.

RESULTS

Of 1 002 258 participants (51.1% women and 48.9% men; mean [SD] age at baseline, 54.6 [10.4] years), 144 366 deaths (9158 deaths from lung cancer) were ascertained during a mean (SD) follow-up of 11.7 (5.3) years. Smoking prevalence for men steadily increased in China and India, whereas it plateaued in Japan and Korea, Singapore, and Taiwan. Among Asian male smokers, the mean age at starting smoking decreased in successive birth cohorts, while the mean number of cigarettes smoked per day increased. These changes were associated with an increasing relative risk of death in association with current smoking in successive birth cohorts of pre-1920, 1920s, and 1930 or later, with hazard ratios for all-cause mortality of 1.26 (95% CI, 1.17-1.37) for the pre-1920 birth cohort, 1.47 (95% CI, 1.35-1.61) for the 1920s birth cohort, and 1.70 (95% CI, 1.57-1.84) for the cohort born in 1930 or later. The hazard ratios for lung cancer mortality were 3.38 (95% CI, 2.25-5.07) for the pre-1920 birth cohort, 4.74 (95% CI, 3.56-6.32) for the 1920s birth cohort, and 4.80 (95% CI, 3.71-6.19) for the cohort born in 1930 or later. Tobacco smoking accounted for 12.5% (95% CI, 8.4%-16.3%) of all-cause mortality in the pre-1920 birth cohort, 21.1% (95% CI, 17.3%-24.9%) of all-cause mortality in the 1920s birth cohort, and 29.3% (95% CI, 26.0%-32.3%) of all-cause mortality for the cohort born in 1930 or later. Tobacco smoking among men accounted for 56.6% (95% CI, 44.7%-66.3%) of lung cancer mortality in the pre-1920 birth cohort, 66.6% (95% CI, 58.3%-73.5%) of lung cancer mortality in the 1920s birth cohort, and 68.4% (95% CI, 61.3%-74.4%) of lung cancer mortality for the cohort born in 1930 or later. For women, tobacco smoking patterns and lung cancer mortality varied substantially by countries and regions.

CONCLUSIONS AND RELEVANCE

In this study, mortality associated with tobacco smoking continued to increase among Asian men in recent birth cohorts, indicating that tobacco smoking will remain a major public health problem in most Asian countries in the coming decades. Implementing comprehensive tobacco-control programs is warranted to end the tobacco epidemic.

Comorbid immune-mediated diseases in inflammatory bowel disease: a nation-wide population-based study

BACKGROUND

Although a higher risk of other immune-mediated diseases has been reported in inflammatory bowel disease (IBD) patients, the risk factors of immune-mediated diseases development and the effect of concomitant immune-mediated diseases on outcomes remain poorly defined.

AIM

To determine the risk factors of incident immune-mediated diseases and the impact of comorbid immune-mediated diseases on outcomes in IBD.

METHODS

Using the National Health Insurance claims data for the entire Korean population, we identified 35 581 IBD patients without immune-mediated diseases and 595 IBD patients with immune-mediated diseases from 2012 to 2013, and follow-up until 2016. We selected four controls by age and sex for comparing with cases.

RESULTS

A total of 35 581 IBD patients without immune-mediated diseases and 142 324 matched controls without immune-mediated diseases were followed from 2014 to 2016 and of these 239 IBD patients and 357 controls developed immune-mediated disease. The overall immune-mediated diseases risk was higher in IBD patients (HR, hazard ratio, 2.47; 95% confidence interval, CI, 2.09-2.91). In a nested case-control study of the IBD cohort, adult patients aged ≥20 years and frequent hospitalisation ≥1 per year were independent risk factors for incident immune-mediated diseases, in contrast, 5-aminosalicylic acid (5-ASA) use had protective effect (odds ratio, 0.61; 95% CI, 0.41-0.90) for developing immune-mediated diseases. In addition, IBD patients with another immune-mediated disease had an increased risk of needing anti-TNF-α agent (HR, 2.40; 95% CI, 2.02-2.84) and developing acute flare (HR, 1.76; 95% CI, 1.37-2.26).

CONCLUSIONS

The incidence of immune-mediated diseases in IBD patients was higher than that of non-IBD population. 5-ASA use may reduce this risk.

The impact of hyperthermia after acute carbon monoxide poisoning on neurological sequelae

This study investigated whether hyperthermia within the first 24 h after presentation was associated with long-term neurological outcomes after acute carbon monoxide (CO) poisoning. This retrospective study included 200 patients with acute severe CO poisoning. Hyperthermia (≥ 37.5°C) developed during the first 24 h after presentation in 55 (27.5%) patients, and poor long-term neurological sequelae assessed at 23 months after acute CO poisoning developed in 19.5% of the patients. The incidence of poor long-term neurological outcomes was significantly higher in the hyperthermia group than in the normothermia group. Patients with poor long-term neurological outcomes had higher maximum temperatures than patients with good outcomes. No significant difference was found in the time of hyperthermia onset within the first day according to the neurological outcomes. Hyperthermia (adjusted odds ratio (aOR) 5.009 (95% confidence interval (CI) 1.556-16.126)) and maximum temperature (aOR 2.581 (95% CI 1.098-6.063)) within the first 24 h after presentation to the emergency department were independently associated with poor long-term neurological outcomes. Body temperature measurements, which are easily and noninvasively recorded at the bedside in any facility, help to predict the risk for poor long-term neurological outcomes. This study carefully emphasizes fastidious control of pyrexia, particularly during the early period after acute CO poisoning.

Non-immune-related hypothyroidism and its relationship with excess iodine

PURPOSE

In iodine-sufficient areas, autoimmune hypothyroidism has been regarded as the major subtype of hypothyroidism. Non-immune-related hypothyroidism has received little attention because it is considered to be rare. The aim of this study was to evaluate the prevalence of non-immune-related hypothyroidism in Korea and to identify its associating factors.

METHODS

A total of 6434 participants in the Korea National Health and Nutrition Examination Survey VI (2013-2015) without known thyroid disease who were examined for thyroid stimulating hormone, free thyroxine, TPO Ab, and urine iodine concentration (UIC) were enrolled. The weighted proportions, demographic variables, and severity of immune-related and non-immune-related hypothyroidism were compared. To assess the effect of iodine on hypothyroidism in TPO Ab positive or negative populations, the weighted prevalence of hypothyroidism was assessed in each population according to UIC or estimated iodine intake subgroups.

RESULTS

The prevalence of undetected hypothyroidism in Korea was 3.8% (n = 233). Of these 233 cases, 171 (71.8%) were non-immune-related. In the TPO Ab negative population, the prevalence of hypothyroidism was increased significantly in the subgroup with UIC between 250 and 749 µg/L (HR 2.12 [1.17, 3.83]) and ≥ 750 µg/L (HR 3.42 [1.93, 6.04]) or the subgroups with estimated iodine intake ≥ 750 µg/day (HR 2.81 [1.64, 4.80]).

CONCLUSIONS

This nationwide study demonstrated that most cases of hypothyroidism in iodine-sufficient areas are non-immune-related and are associated with excess iodine above a certain level. More attention to this unrecognized but widespread potential health risk is needed.

Abstract 4234: Association between educational level and mortality: A pooled analysis of over 694,000 individuals in the Asia Cohort Consortium

Background: Higher educational levels have been linked to reduced risk of death in previous studies. Most of these studies, however, were conducted in the United States and Europe.

Methods: We performed a pooled analysis to evaluate the association between educational levels and risk of death among 694,434 Asian individuals from 15 prospective cohort studies that participated in the Asia Cohort Consortium. The analysis included 103,023 deaths during a mean follow-up period of 12.5 years, among which 33,945 were due to cancer and 34,645 were due to cardiovascular diseases (CVD). We employed Cox proportional hazards regression models to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the association between educational level and the risk of death after adjusting for potential confounders.

Results: Higher educational levels were significantly associated with lower risk of death from all causes; compared to a low educational level (≤ primary school), HRs and 95% CIs for secondary education, trade/technical education, and ≥ university degree were 0.86 (0.83-0.90), 0.80 (0.71-0.89), and 0.68 (0.61-0.75), respectively (Ptrend &lt;0.0001). Similar associations were observed for cancer or CVD-specific mortality, with HRs of 0.93 (0.89-0.97), 0.87 (0.78-0.97), and 0.79 (0.71-0.87) for risk of cancer deaths with increasing levels of education (Ptrend = 0.003) and HRs of 0.86 (0.81-0.91), 0.75 (0.64-0.87), and 0.64 (0.57-0.73) for risk of CVD deaths with increasing levels of education (Ptrend &lt;0.0001). The pattern of the association among East Asians and South Asians was similar; compared to ≤ primary school, HR (95% CI) for all-cause mortality associated with ≥ university degree was 0.68 (0.61-0.76) among 539,724 East Asians (Chinese, Japanese, and Korean) and 0.61 (0.54-0.69) among 154,710 South Asians (Indians and Bangladeshis) included in this analysis.

Conclusions: Higher educational level was associated with substantially lower risk of death in Asian populations including both East and South Asians.

Citation Format: Keming Yang, Ying Zhang, Eiko Saito, Yu Chen, Prakash C. Gupta, Yu-Tang Gao, Akiko Tamakoshi, Yong-Bing Xiang, Woon-Puay Koh, Norie Sawada, Kemmyo Sugiyama, Yasutake Tomata, Atsuko Sadakane, Chisato Nagata, San-Lin You, Renwei Wang, Myung-Hee Shin, Habibul Ahsan, Wen-Harn Pan, Mangesh S. Pednekar, Jian-Min Yuan, Xiao-Ou Shu, Hui Cai, Shoichiro Tsugane, Ichiro Tsuji, Seiki Kanemura, Keiko Wada, Yoon-Ok Ahn, Kotaro Ozasa, John D. Potter, Wei Zheng, Hongmei Nan. Association between educational level and mortality: A pooled analysis of over 694,000 individuals in the Asia Cohort Consortium [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4234.

Anaplastic lymphoma kinase rearrangement in surgically resected stage IA lung adenocarcinoma

Background

It has not been determined if adjuvant chemotherapy would be helpful for completely resected early-stage lung adenocarcinoma even with unfavorable genetic markers. As the positive anaplastic lymphoma kinase (ALK) rearrangement is associated with aggressive clinical feature in lung adenocarcinoma, we evaluated the treatment outcomes of completely resected stage IA lung adenocarcinoma according to initial ALK status.

Methods

This is a retrospective cohort study including 309 patients with surgically resected stage IA lung adenocarcinoma from February 2010 to December 2013. Patients were screened for ALK rearrangement using immunohistochemistry. A positive ALK status was defined as an immunohistochemistry score of 2+ or more. Both disease-free survival (DFS) and the initial recurrence pattern were analyzed according to ALK status.

Results

Twenty-three (7.4%) patients had ALK-positive adenocarcinoma. During the median follow-up of 35.8 months, recurrence developed in 34 (11.0%) patients. The patients with ALK-positive tumor had significantly lower 5-year DFS rate (62.4%) compared to those with ALK-negative tumor (86.5%; P=0.038). The multivariable analysis showed that ALK rearrangement was associated with a higher risk of disease recurrence (adjusted hazard ratio =2.64; 95% confidence interval, 1.08-6.44). In addition, patient with ALK-positive tumor showed more frequent recurrence in regional lymph nodes compared with those with ALK-negative tumor (83.3% vs. 28.6%; P=0.031).

Conclusions

In patients with completely resected stage IA lung adenocarcinoma, ALK rearrangement was associated with unfavorable DFS and more frequent regional lymph node metastasis. Therefore, careful surveillance for recurrence should be performed in this subset of patients.

Association of leisure-time physical activity with total and cause-specific mortality: a pooled analysis of nearly a half million adults in the Asia Cohort Consortium

BACKGROUND

Most previous studies evaluating the association between leisure-time physical activity (LTPA) and risk of death were conducted among generally healthy individuals of European ancestry. We investigated the association of LTPA with all-cause and cause-specific mortality among East Asian populations, including healthy individuals and those with existing chronic diseases, which has been less well characterized.

METHODS

We performed pooled analyses among 467 729 East Asian individuals recruited in nine prospective cohorts included in the Asia Cohort Consortium. Cox proportional hazards regressions were used to derive hazard ratios (HRs) and 95% confidence intervals (CIs) associated with LTPA after adjusting for age, sex, education and marital and smoking status.

RESULTS

During a mean follow-up period of 13.6 years, 65 858 deaths were identified. Compared with those who reported no or less than 1 h of LTPA per week, an inverse association was observed between the amount of LTPA and all-cause and cause-specific mortality (P for trend < 0.001). The strength of the inverse association was stronger for death due to cardiovascular diseases and causes other than cancer deaths. An inverse association of LTPA with total mortality was observed among individuals with a severe and often life-threatening disease: cancer, stroke or coronary heart disease [hazard ratio (HR) = 0.81, 95% CI = 0.73-0.89 for high vs low LTPA) and those with other chronic diseases such as diabetes or hypertension (HR = 0.86, 95% CI = 0.80-0.93 for high vs low LTPA). No clear modifying effects by sex, body mass index or smoking status were identified.

CONCLUSIONS

Regular participation in LTPA is associated with reduced mortality in middle-aged and elder Asians regardless pre-existing health conditions.

Age- and gender-specific reference intervals of TSH and free T4 in an iodine-replete area: Data from Korean National Health and Nutrition Examination Survey IV (2013-2015)

BACKGROUND

Establishment of the reference interval of thyroid-stimulating hormone (TSH) is critical in the diagnosis of thyroid dysfunction and is affected by age, gender, iodine nutrition, and ethnicity. The aim of this study was to determine the reference intervals of TSH and free thyroxin (FT4) from a large, nationwide data of Korea where iodine intake is more than adequate.

METHODS

We analyzed data from the Korea National Health and Nutrition Examination Survey VI that measured serum TSH, FT4, and thyroid peroxidase antibody from 7,061 individuals (urinary iodine measurement in 6,565). Age- and gender-specific reference intervals were established from 95% confidence limits from the 2.5 to 97.5 percentile of TSH (log-transformed) and FT4 in reference populations.

RESULTS

The geometric mean of TSH was 2.16 ± 0.01 mIU/L, with the lowest value found in the middle aged group (2.04 ± 0.02 mIU/L) and higher values noted in age groups of 10-19 and over 70 years (2.38 ± 0.02 and 2.32 ± 0.07 mIU/L, respectively). The association of TSH and age was U-shaped. The overall reference interval of TSH was 0.59-7.03 mIU/L. Mean FT4 was 1.25 ± 0.003 ng/dL (16.09 ± 0.039 pmol/L), and it showed a small but continuous decrease after 20 years of age (P < 0.001). There was a significant positive correlation between TSH and urine iodine concentration (r = 0.154, P < 0.001).

CONCLUSIONS

The reference interval of TSH in Korea, where iodine intake is above the requirement, was 0.59-7.03 mIU/L and showed U-shaped change with age, which was a similar pattern to iodine intake. The reference interval of FT4 was 0.92-1.60 ng/dL. The geometric mean and upper limit of TSH were higher than those of Western populations, reflecting the paramount importance of iodine intake on thyroid function.

Urinary iodine concentration and thyroid hormones: Korea National Health and Nutrition Examination Survey 2013-2015

PURPOSE

An epidemiologic study that evaluated population's iodine nutrition status and its relationship with thyroid hormones is lacking in iodine-sufficient area. This nationwide study aimed to evaluate the iodine nutrition status in Korea and relationship between urine iodine concentration (UIC) and thyroid hormones.

METHODS

A total of 8318 subjects of the Korea National Health and Nutrition Examination Survey VI (2013-2015) with UIC and thyroid hormone evaluation were included. Median UIC level and estimated 24-h iodine intake were calculated. The prevalence of iodine deficiency or excess was obtained using estimated average requirement or above the tolerable upper intake level cut-point method by estimated iodine intake. We analyzed UIC with regard to age, sex, social economic status, and geographic characteristics.

RESULTS

The median UIC in general population and estimated iodine intake in adult population were 293.9 μg/L (above requirement according to World Health Organization classification) and 249.3μg/day, respectively. The prevalence of iodine deficiency and excess was 14.0 and 13.4%. The median UIC was higher among SAC [511 (299.9-948.5)] and lower among seventies [251.2 (98.9-761.6)] compared to other age groups. The median UIC increased with household income level (p for trend < 0.001). The subjects living in rural and inland region had lowest UIC among the enrolled subjects. The subgroups with higher median UIC were associated with higher mean TSH levels.

CONCLUSIONS

This first nationwide study in Korea demonstrated that the median of UIC and estimated iodine intake lie at nearly 300 µg/L and 250 µg/day, respectively, which shows an overall excellent iodine nutrition.

Association between type 2 diabetes and risk of cancer mortality: a pooled analysis of over 771,000 individuals in the Asia Cohort Consortium

AIMS/HYPOTHESIS

The aims of the study were to evaluate the association between type 2 diabetes and the risk of death from any cancer and specific cancers in East and South Asians.

METHODS

Pooled analyses were conducted of 19 prospective population-based cohorts included in the Asia Cohort Consortium, comprising data from 658,611 East Asians and 112,686 South Asians. HRs were used to compare individuals with diabetes at baseline with those without diabetes for the risk of death from any cancer and from site-specific cancers, including cancers of the oesophagus, stomach, colorectum, colon, rectum, liver, bile duct, pancreas, lung, breast, endometrium, cervix, ovary, prostate, bladder, kidney and thyroid, as well as lymphoma and leukaemia.

RESULTS

During a mean follow-up of 12.7 years, 37,343 cancer deaths (36,667 in East Asians and 676 in South Asians) were identified. Baseline diabetes status was statistically significantly associated with an increased risk of death from any cancer (HR 1.26; 95% CI 1.21, 1.31). Significant positive associations with diabetes were observed for cancers of the colorectum (HR 1.41; 95% CI 1.26, 1.57), liver (HR 2.05; 95% CI 1.77, 2.38), bile duct (HR 1.41; 95% CI 1.04, 1.92), gallbladder (HR 1.33; 95% CI 1.10, 1.61), pancreas (HR 1.53; 95% CI 1.32, 1.77), breast (HR 1.72; 95% CI 1.34, 2.19), endometrium (HR 2.73; 95% CI 1.53, 4.85), ovary (HR 1.60; 95% CI 1.06, 2.42), prostate (HR 1.41; 95% CI 1.09, 1.82), kidney (HR 1.84; 95% CI 1.28, 2.64) and thyroid (HR 1.99; 95% CI 1.03, 3.86), as well as lymphoma (HR 1.39; 95% CI 1.04, 1.86). Diabetes was not statistically significantly associated with the risk of death from leukaemia and cancers of the bladder, cervix, oesophagus, stomach and lung.

CONCLUSIONS/INTERPRETATION

Diabetes was associated with a 26% increased risk of death from any cancer in Asians. The pattern of associations with specific cancers suggests the need for better control (prevention, detection, management) of the growing epidemic of diabetes (as well as obesity), in order to reduce cancer mortality.

Radiotherapy for gastric mucosa-associated lymphoid tissue lymphoma: dosimetric comparison and risk assessment of solid secondary cancer

Purpose

To determine the optimal radiotherapy technique for gastric mucosa-associated lymphoid tissue lymphoma (MALToma), we compared the dosimetric parameters and the risk of solid secondary cancer from scattered doses among anterior-posterior/posterior-anterior parallel-opposed fields (AP/PA), anterior, posterior, right, and left lateral fields (4_field), 3-dimensional conformal radiotherapy (3D-CRT) using noncoplanar beams, and intensity-modulated radiotherapy composed of 7 coplanar beams (IMRT_co) and 7 coplanar and noncoplanar beams (IMRT_non).

Materials and Methods

We retrospectively generated 5 planning techniques for 5 patients with gastric MALToma. Homogeneity index (HI), conformity index (CI), and mean doses of the kidney and liver were calculated from the dose-volume histograms. Applied the Biological Effects of Ionizing Radiation VII report to scattered doses, the lifetime attributable risk (LAR) was calculated to estimate the risk of solid secondary cancer.

Results

The best value of CI was obtained with IMRT, although the HI varied among patients. The mean kidney dose was the highest with AP/PA, followed by 4_field, 3D-CRT, IMRT_co, and IMRT_non. On the other hand, the mean liver dose was the highest with 4_field and the lowest with AP/PA. Compared with 4_field, the LAR for 3D-CRT decreased except the lungs, and the LAR for IMRT_co and IMRT_non increased except the lungs. However, the absolute differences were much lower than <1%.

Conclusion

Tailored RT techniques seem to be beneficial because it could achieve adjacent organ sparing with very small and clinically irrelevant increase of secondary solid cancer risk compared to the conventional techniques.

Coffee Intake and Liver Enzyme Association in Korean Immigrants and Japanese: A Comprehensive Cross-Sectional Study

OBJECTIVES

Significant inverse association between coffee intake and the levels of liver enzymes has been reported. We demonstrated higher prevalence of metabolic syndrome in Korean immigrants (KIs) than in indigenous Japanese (IJs). The aim of this study was to investigate whether the association between coffee intake and liver enzyme levels was different between the 2 ethnic groups.

METHODS

This study is a cross-sectional study including a total of 966 subjects comprising KIs and IJs. The association between the quintiles of coffee intake and dichotomous values of liver enzymes was evaluated by logistic regression analysis in KIs, IJs, a high-risk group (current smokers or alcohol drinkers ≥45 g/day), and a low-risk group (non-smokers and alcohol drinkers <45 g/day).

RESULTS

In KIs, a significant inverse association between coffee intake and serum aspartate aminotransferase (AST) levels was observed. In the IJs, a significant inverse association between coffee intake and serum alanine aminotransferase levels was observed. In the high-risk group, a significant inverse association between coffee intake and serum AST and gamma-glutamyltransferase levels was observed.

CONCLUSION

No difference was observed between KIs and IJs regarding the association between coffee and liver enzymes. Coffee might inhibit hepatic damage by alcohol drinking and smoking.

Donor Safety and Recipient Liver Function After Right-Lobe Liver Transplantation From Living Donors With Gilbert Syndrome

BACKGROUND

Donor safety is the most important aspect in living-donor liver transplantation (LDLT). Gilbert syndrome is an autosomal recessive condition that is a common cause of isolated unconjugated hyperbilirubinemia, and its prevalence is not negligibly low in the general population. This study intended to assess donor safety and recipient liver function after LDLT with the use of right liver grafts from living donors with Gilbert syndrome.

METHODS

Among 2,140 right liver transplantations performed from January 2002 to December 20113 at our institution, we identified 12 living donors (0.6%) who showed a preoperative serum total bilirubin level of ≥2 mg/dL. These donors were clinically diagnosed with Gilbert syndrome. The clinical outcomes of these donors and their recipients were analyzed retrospectively.

RESULTS

The mean donor age was 24.6 ± 7.1 years, and 11 donors were male. All subjects met the preoperative evaluation conditions for right liver donation except for the level of unconjugated hyperbilirubinemia. The mean serum total bilirubin level of the donors was 2.23 ± 0.20 mg/dL before and 1.79 ± 0.61 mg/dL 1 year after right liver donation. The preoperative donor direct bilirubin level was 0.43 ± 0.19 mg/dL. The preoperative indocyanine green retention rate at 15 minutes was 8.2 ± 2.8%. All donors and recipients recovered uneventfully and were alive at the time of writing. The recipient serum total bilirubin level was 1.29 ± 0.47 mg/dL 1 year after LDLT.

CONCLUSIONS

We suggest that LDLT with living donors with Gilbert syndrome can be safely performed, but that a meticulous preoperative evaluation is vital to maximize donor safety.

Abstract 3418: Differential prognostic effect of smoking and multivitamin use on lung cancer survival by sex

Incidence of lung cancer is decreasing among men and increasing among women in developed countries and also in Korea. However, mortality of lung cancer is still the highest among male cancers. Smoking is one of the group 1 carcinogens for lung cancer development, but its prognostic effect on lung cancer survival is not well established. Beta-carotene supplement increased the risk of lung cancer among smokers but the role of multivitamin supplement on the risk and survival of lung cancer is unclear either. We aimed to evaluate the association between smoking and multivitamin use on lung cancer survival by sex. We interviewed 910 pathologically confirmed lung cancer patients who were diagnosed between 2010 and 2012 in Samsung Medical Center. Questionnaire included current smoking status, age at first smoking, daily smoking amount, alcohol intake, past medical history, and multivitamin use. Pathological type, stage, and treatment information was collected from the electronic medical records. We followed the patients until December 31, 2012. Hazard Ratios (HR) and 95% Confidence Intervals (CI) were estimated using Cox's proportional hazard model (SAS9.4). We found significant difference in age at diagnosis, pathological type and stage between male and female patients; Female patients were younger, smoked less, used more multivitamin, and had more adenocarcinoma and earlier stage cancer than male patients. Smoking increased the risk of lung cancer mortality among female patients only. HR for lung cancer mortality for those who smoked more than 40 pack-years compared to those who never smoked was 5.64 (95%CI = 1.43, 22.28) in women and 1.17 (95%CI = 0.61, 2.26) in men (p-interaction = 0.01) when adjusted for age, stage, and pathologic type. Multivitamin use also increased the risk of lung cancer mortality among female patients only. HR for lung cancer mortality for multivitamin users was 4.14(95%CI = 1.77, 9.73) in women and 1.46 (95%CI = 0.71, 3.00) in men (p-interaction = 0.17). The association between multivitamin use and lung cancer mortality was strongest among female non-smokers (HR = 4.10, 95%CI = 1.72, 9.77). In conclusion, smoking and multivitamin use worsen the survival of female lung cancer. Prognostic effect of multivitamin use may be stronger among non-smokers.

Citation Format: Mi Yang, Hyun-Kyung Oh, Young Mog Shim, Myung-Hee Shin. Differential prognostic effect of smoking and multivitamin use on lung cancer survival by sex. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3418.

Abstract A35: Association between calcium and beta-carotene intake and risk of prostate cancer in Seoul Male Cohort Study

Prostate cancer is a 5th common cancer among Korean male population, but the incidence is increasing rapidly (12.1% per year). The 5-year relative survival of prostate cancer in Korea is relatively poor (80.1% for 2001-2005 incident cases) compared to other developed countries (99.4%, 2001-2007 incident cases in SEER U.S.A), probably due to later stage at diagnosis. Dietary factors are strongly related to the risk of prostate cancer. Calcium and beta-carotene has been suggested to have a positive and an inverse association with the risk of prostate cancer, respectively. However, several recent studies showed no association with dietary calcium and either no or a positive association with bet-carotene, especially among smokers. We aimed to test the association between calcium and beta-carotene intake and the risk of prostate cancer in a Korean male population. Seoul Male Cohort was established in 1993. Members were recruited from the male beneficiaries of the Korean Health Insurance Company, who were aged 40-59 and living in Seoul. A lifestyle questionnaire survey was conducted through mailing. Dietary intake was measured using a quantitative food frequency questionnaire with 88 food items. Nutrient intake was calculated and the amount was categorized into quartiles (q1-the lowest quartile, q4-the highest quartile). Cancer occurrence was identified through data linkage to the Korean Central Cancer Registry and Korean Death Records. A total of 14,533 members were followed up until December 31, 2008, and 123 incident prostate cancer cases were identified. Multivariable hazard ratios (aHR) and 95% confidence intervals (95%CI) were calculated using Cox's regression model. There was no significant difference between prostate cancer patients and non-cancer cohort members in terms of initial age, family history, body mass index, alcohol intake, and smoking, whereas prostate cancer patients had higher education (p&lt;0.036). Higher calcium intake was not associated with prostate cancer (q4 vs. q1, aHR=0.98, 95%CI = 0.51-1.88, ptrend=0.81). Moderate, but not significant, risk increase by beta-carotene intake was observed (q4 vs. q1, aHR=1.60, 95%CI = 0.93-2.77, ptrend=0.06). Baseline smoking rate among cohort members was high (76%). Therefore, we observed the same result in a subgroup analysis with smokers only.

In conclusion, calcium intake did not increase the risk of prostate cancer, and beta-carotene intake may increase the risk of prostate cancer in a Korean male population.

Citation Format: Myung-Hee Shin, Jong-Myon Bae, Moo-Song Lee, Dong-Hyun Kim, Zhong-Min Li, Yoon-Ok Ahn. Association between calcium and beta-carotene intake and risk of prostate cancer in Seoul Male Cohort Study. [abstract]. In: Proceedings of the Thirteenth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2014 Sep 27-Oct 1; New Orleans, LA. Philadelphia (PA): AACR; Can Prev Res 2015;8(10 Suppl): Abstract nr A35.

Vegetable intake, but not fruit intake, is associated with a reduction in the risk of cancer incidence and mortality in middle-aged Korean men

BACKGROUND

Few prospective studies have examined the preventive role of fruit and vegetable intakes against cancer in Asian populations.

OBJECTIVE

This prospective study evaluated the associations between total fruit intake, total vegetable intake, and total fruit and vegetable intake and total cancer incidence and mortality.

METHODS

This prospective cohort study included 14,198 men 40-59 y of age enrolled in the Seoul Male Cohort Study from 1991 to 1993. Fruit and vegetable intakes were assessed by a validated food-frequency questionnaire. We used Cox proportional hazard regression models to compute RR ratios and 95% CIs.

RESULTS

During the follow-up period from 1993 to 2008, 1343 men were diagnosed with cancer, and 507 died of cancer. Total vegetable intake was linearly associated with cancer incidence but was nonlinearly associated with cancer mortality; by comparing ≥ 500 g/d with <100 g/d of total vegetable intake, the multivariable-adjusted RR for total cancer incidence was 0.72 (95% CI: 0.58, 0.90; P-trend: 0.02; P-nonlinearity: 0.06). For total cancer mortality, the multivariable-adjusted RRs comparing 100 to <200 g/d, 200 to <300 g/d, 300 to <500 g/d, and ≥ 500 g/d with <100 g/d of total vegetable intake were 0.68 (95% CI: 0.53, 0.88), 0.75 (95% CI: 0.57, 0.98), 0.72 (95% CI: 0.54, 0.95), and 0.67 (95% CI: 0.47, 0.95), respectively (P-trend: 0.09; P-nonlinearity: 0.01). No associations were found between total fruit intake and total cancer incidence and mortality; ≥ 300 g/d vs. <50 g/d, RR: 1.04 (95% CI: 0.87, 1.25; P-trend = 0.56) for incidence and RR: 0.89 (95% CI: 0.66, 1.21; P-trend = 0.71) for mortality.

CONCLUSIONS

Our findings suggest that total vegetable intake is linearly associated with cancer incidence but nonlinearly associated with total cancer mortality in middle-aged Korean men. However, total fruit intake is not associated with total cancer incidence or mortality.

The ossification pattern in paediatric occipito-cervical spine: is it possible to estimate real age?

AIM

To retrospectively analyse the synchondrosis from the occipital bone to the whole cervical spine and determine the feasibility and validity of age estimation using computed tomography (CT) images.

MATERIAL AND METHODS

A total of 231 cervical spine or neck CT images of young children (<7 years of age) were examined. Twelve ossification centres were assessed (occiput: n = 2; atlas: n = 2; axis, n = 6; whole sub-axial vertebra: n = 2), and the ossification process was graded as open (O, fully lucent), osseous bridging (B, partially ossified), and fusion (F, totally ossified). After the first analysis was completed, the resulting chronological chart was used to estimate the age of 10 new cases in order to confirm the usefulness of the chart.

RESULTS

Infancy was easily estimated using the sub-axial or C2 posterior ossification centres, while the posterior occipital regions provided good estimation of age between 1-2 years. The most difficult period for accurate age estimation was between 2-4 years. However, the C2 anterior (neurocentral ossification) and C1 posterior regions did yield information to help determine the age around 3 years. The anterior occipital region was useful for age estimation between 4-5 years, and the C1-anterior region was potentially useful to help decide among the other parameters. The test for age estimation (TAE) had a very high ICC score (0.973) among the three observers.

CONCLUSION

Segmentalised analysis can enhance the ability to estimate real age, at least by the year. The analysis of the occipital bone made a strong contribution to the usefulness of the chorological chart. An organised chronological chart can provide readily available information for age estimation, and the primary application of the above data (TAE) demonstrated the validity of this approach.

Thymic epithelial tumors: prognostic determinants among clinical, histopathologic, and computed tomography findings

BACKGROUND

The Masaoka-Koga staging system has been known as the strongest prognostic factor for both survival and recurrence of thymic epithelial tumor (TET). The purpose of our study was to find prognostic determinants among computed tomography (CT), histopathologic, and clinical features of TET.

METHODS

Two radiologists reviewed retrospectively CT findings of 437 patients (male 242, female 195; mean age, 51 years) with TET. With medical record review, surgico-histopathologic results were subcategorized into Masaoka-Koga stages I through IV and World Health Organization histopathologic classifications A-B1, B2-B3, and carcinoma. Overall survival and progression-free survival were analyzed. Clinical, histopathologic, and CT features were correlated from each other.

RESULTS

In all, 437 tumors were in Masaoka-Koga stage I (n = 147, 33.6%), stage II (n = 121, 27.7%), stage III (n = 76, 17.4%), or stage IV (n = 93, 21.3%); A and B1 (n = 114, 26.1%) and B2 and B3 TET (n = 223, 51.0%); and thymic carcinoma (n = 100, 22.9%). In multivariable analyses, age, Masaoka-Koga stage IV, thymic carcinoma, and CT stages III and IV were significantly correlated with overall survival (p < 0.05), whereas adjuvant treatment, Masaoka-Koga stages III and IV, World Health Organization B2 and B3, thymic carcinoma, R2 resection, CT size, and CT stage IV were significantly associated with progression-free survival (p < 0.05). Computed tomography stages showed moderate association with Masaoka-Koga stages (K = 0.621).

CONCLUSIONS

For TET, CT staging is effective in distinguishing both overall survival and progression-free survival, and patients with Masaoka-Koga stage IV or thymic carcinoma or CT stage IV have the worst prognosis.

Abstract 1273: Association between smoking, alcohol, and salty food intake and risk of stomach cancer by topographic location and histological type in Seoul Male Cohort

Incidence of stomach cancer has been declining in South Korea, but it still remains as the highest among men in the country. Cancers of upper and lower parts of stomach, and diffuse and intestinal type of stomach are thought to have different risk factors. Smoking, alcohol, and salty food intake are consistently associated with the risk of stomach cancer, but possible differential associations by topographic location and histological type are not well established. We evaluated the associations between smoking, alcohol, and salty food intake and the risk of cancers in upper (cardia and fundus), middle (body), and lower parts (antrum) of stomach, and of diffuse and intestinal type of stomach cancer in a prospective cohort study in Korea. Seoul Male Cohort was established in 1993. Members were recruited from the male beneficiaries of the Korean Health Insurance Company, who were aged 40-59 and living in Seoul. A lifestyle questionnaire survey was conducted through mailing. Dietary intake was measured using a quantitative food frequency questionnaire with 88 food items. Cancer occurrence was identified through data linkage to the Korean Central Cancer Registry and Korean Death Records. A total of 14,533 members were followed up until December 31, 2008, and 362 incident stomach cancer cases were identified. Multivariable hazard ratios (aHR) and 95% confidence intervals (95% CI) were calculated using Cox's regression model. None of the smoking, alcohol, and salty food intake was associated with risk of upper stomach cancer. Smoking had strongest association with risk of mid stomach cancer. Men who smoked currently and who stopped smoking for less than 4 years had 2.57 and 3.28 times higher risk of mid stomach cancer than never smokers (95% CI = 1.26-5.26, 1.36-7.96, respectively, ptrend=0.0036). Ex-smokers who stopped smoking for 4 or more years had no increase in risk of mid stomach cancer. Alcohol also had strongest association with risk of mid stomach cancer. The aHR of mid stomach cancer for those who had alcohol more than 45g/day compared to non-drinkers was 2.13 (95% CI = 0.94-4.82, ptrend=0.0353). Salty food and sodium intake had strongest association with risk of lower stomach cancer (Highest vs. lowest quartile, aHR=1.53 (95%CI = 0.93-2.52, ptrend=0.0670) for salty food, aHR=2.25 (95%CI = 1.18- 4.31, ptrend=0.0442) for sodium). Current smoking was strongly associated with both diffuse (aHR=2.44) and intestinal type of stomach cancer (aHR=1.87). Ex-smoking, alcohol, and salty food intake had significant positive association with intestinal type of stomach cancer, but not with diffuse type. In conclusion, smoking, alcohol, and salty food intake were mostly associated with risk of mid and lower stomach cancer and intestinal type of stomach cancer.

Citation Format: Myung-Hee Shin, Seon-Mi Hwang, Min-Gew Choi, Duk-Hwan Kim, Jong-Myon Bae, Moo-Song Lee, Dong-Hyun Kim, Zhong-Min Li, Yoon-Ok Ahn. Association between smoking, alcohol, and salty food intake and risk of stomach cancer by topographic location and histological type in Seoul Male Cohort. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1273. doi:10.1158/1538-7445.AM2014-1273

Cigarette smoking and prostate cancer risk: negative results of the Seoul Male Cancer Cohort Study

We evaluated cigarette smoking as a risk factor for prostate cancer in a prospective, population-based cohort study. The subjects were 14,450 males among the participants in the Seoul Male Cancer Cohort Study who had at least 1-year follow-up. They were followed up between 1993 and 2008. During the 16-year follow-up period, 87 cases of prostate cancer occurred over the 207,326 person-years of the study. The age-adjusted relative risks of past and current smokers at entry were 0.60 (95%CI: 0.34-1.06) and 0.70 (95%CI: 0.43-1.13), respectively, suggesting that cigarette smoking may not be a risk factor for prostate cancer. The relationship between prostate cancer and other modifiable factors, such as Westernized diet, should be studied with the goal of establishing prevention programs for prostate cancer.

Abstract T P345: Cardiovascular Health Metrics and All-cause and Cardiovascular Disease Mortality among Middle Aged Men in Korea: The Seoul Male Cohort Study

Background: In Korea, Cerebrovascular and cardiovascular diseases (CVD) were the second leading cause of deaths in 2011. In 2010, the American Heart Association (AHA) published cardiovascular health metrics (CVHM) aimed at reducing deaths from all CVDs and stroke, and improving the cardiovascular health of the population as a whole. Despite their implications, the AHA’s metrics have not been broadly studied or previously applied to an Asian population.

Objectives: This study estimated the combined association of cardiovascular health behaviors on the risk of all-cause and CVD mortality in middle-aged men in Korea.

Methods: In total, 14,533 men aged 40-59 years were enrolled in 1993 and followed-up through 2011. CVHM defined the following lifestyles proposed by the AHA: smoking, physical activity, BMI, healthy diet score, total cholesterol, blood pressure, and fasting blood glucose. The CVHMs score was calculated as a single categorical variable, by assigning 1 point to each ideal healthy behavior vs. 0 points otherwise. All subjects were classified as meeting 0-7 CVHM. The principal outcome variables were all-cause and CVD mortality. The Cox proportional hazard regression model was used to estimate the hazard ratio (HR) of cardiovascular health behavior, and CVHMs score. PARs were calculated from significant CVHMs.

Results: During 266,482.8 person-years of follow-up, there were 1,314 deaths in total. Current smoking, blood pressure, and fasting blood glucose were significantly associated with all-cause and CVD mortality. The adjusted PARs for the 3 significant metrics combined were 81% (95% CI, 50-94%) and 96% (66-99%) for all-cause and CVD mortality, respectively. More ideal CVHM was significantly associated with lower risks of all-cause and CVD mortality ( p-trend<.0001 ). The adjusted HRs of the groups with 6-7 vs. 0-2 ideal CVHM were 0.49 (0.35-0.70) and 0.23 (0.10-0.57) for all-cause and CVD mortality, respectively.

Conclusions: Among ideal cardiovascular health behaviors, non-smoking, normal blood pressure, and recommended fasting blood glucose levels associated with reduced risks of all-cause and total CVD mortality. There was a strong trend towards decreased all-cause and CVD mortality risk with increasing the number of ideal CVHMs.

Cardiovascular health metrics and all-cause and cardiovascular disease mortality among middle-aged men in Korea: the Seoul male cohort study

Objectives

This study estimated the association of cardiovascular health behaviors with the risk of all-cause and cardiovascular disease (CVD) mortality in middle-aged men in Korea.

Methods

In total, 12 538 men aged 40 to 59 years were enrolled in 1993 and followed up through 2011. Cardiovascular health metrics defined the following lifestyle behaviors proposed by the American Heart Association: smoking, physical activity, body mass index, diet habit score, total cholesterol, blood pressure, and fasting blood glucose. The cardiovascular health metrics score was calculated as a single categorical variable, by assigning 1 point to each ideal healthy behavior. A Cox proportional hazards regression model was used to estimate the hazard ratio of cardiovascular health behavior. Population attributable risks (PARs) were calculated from the significant cardiovascular health metrics.

Results

There were 1054 total and 171 CVD deaths over 230 690 person-years of follow-up. The prevalence of meeting all 7 cardiovascular health metrics was 0.67%. Current smoking, elevated blood pressure, and high fasting blood glucose were significantly associated with all-cause and CVD mortality. The adjusted PARs for the 3 significant metrics combined were 35.2% (95% confidence interval [CI], 21.7 to 47.4) and 52.8% (95% CI, 22.0 to 74.0) for all-cause and CVD mortality, respectively. The adjusted hazard ratios of the groups with a 6-7 vs. 0-2 cardiovascular health metrics score were 0.42 (95% CI, 0.31 to 0.59) for all-cause mortality and 0.10 (95% CI, 0.03 to 0.29) for CVD mortality.

Conclusions

Among cardiovascular health behaviors, not smoking, normal blood pressure, and recommended fasting blood glucose levels were associated with reduced risks of all-cause and CVD mortality. Meeting a greater number of cardiovascular health metrics was associated with a lower risk of all-cause and CVD mortality.

Seroepidemiology of hepatitis a infection in northeastern china, Korea, and Japan

Objectives

The epidemiological patterns of endemic hepatitis A virus (HAV) are unclear in northeastern Asia depending on the ethnicity of the country in question. The purpose of this study was to investigate the seroprevalence of HAV in northeastern China, South Korea, and Japan.

Methods

A total of 1,500 serum samples were collected from five groups of inhabitants (300 each) who were over 40 years of age (Korean Chinese, indigenous Chinese, South Korean, Korean living in Japan, and indigenous Japanese). The samples were screened for antibodies to HAV using an enzyme-linked immunosorbent assay.

Results

Positivity for HAV antibodies was 93.7% (95% confidence interval [CI]: 90.9–96.4) in Koreans living in northeastern China, 99.7% (95% CI: 99.0–100.3) in indigenous Chinese, 98.0% (95% CI: 96.4–99.6) in indigenous Koreans, 33.3% (95% CI: 28.0–38.7) in Koreans living in Japan, and 20.4% (95% CI: 15.8–25.0) in indigenous Japanese persons. The overall anti-HAV prevalence was not significantly different between northeastern China and South Korea, but it was different in Japan.

Conclusions

These results indicate that differences in seroprevalence can be attributed to geological, environmental, and socioeconomic conditions rather than ethnicity.

Obesity is a risk factor for thyroid cancer in a large, ultrasonographically screened population

OBJECTIVE

Obesity is a well-known risk factor for many cancers, including those of the esophagus, colon, kidney, breast, and skin. However, there are few reports on the relationship between obesity and thyroid cancer. We conducted this study to determine whether obesity is a risk factor for thyroid cancer by systematically screening a selected population by ultrasonography.

DESIGN AND METHODS

We obtained data from 15,068 subjects that underwent a routine health checkup from 2007 to 2008 at the Health Screening and Promotion Center of Asan Medical Center. Thyroid ultrasonography was included in the checkup, and suspicious nodules were examined by ultrasonography-guided aspiration. Those with a history of thyroid disease or family history of thyroid cancer were excluded from this study.

RESULTS

In total, 15,068 subjects, 8491 men and 6577 women, were screened by thyroid ultrasonography. Fine-needle aspiration cytology was performed in 1427 of these patients based on the predefined criteria and thyroid cancer was diagnosed in 267 patients. The prevalence of thyroid cancer in women was associated with a high BMI (per 5 kg/m(2) increase) (odds ratios (OR)=1.63, 95% CI 1.24-2.10, P<0.001), after adjustment for age, smoking status, and TSH levels. There was no positive correlation between the prevalence of thyroid cancer in men and a high BMI (OR=1.16, 95% CI 0.85-1.57, P=0.336). There was no association between age, fasting serum insulin, or basal TSH levels and thyroid cancer in either gender.

CONCLUSIONS

Obesity was associated with a higher prevalence of thyroid cancer in women when evaluated in a routine health checkup setting. This association between risk factor and disease was unrelated to serum insulin and TSH levels. Additional studies are needed to understand the mechanism(s) behind the association of obesity with thyroid cancer risk.

Pulmonary tuberculosis and lung cancer risk in current smokers: the Seoul Male Cancer Cohort Study

Authors evaluated pulmonary tuberculosis (PTB) history as a risk factor for lung cancer in current male smokers in a prospective, population-based cohort study. The subjects were the 7,009 males among the participants in the Seoul Male Cancer Cohort Study for whom there was full information on PTB history and smoking habits. With a 16-yr follow-up, 93 cases of lung cancer occurred over the 99,965 person-years of the study. The estimated relative risk (RR) of PTB history of current smokers in lung cancer after adjusting for three confounders - intake of coffee and tomatoes, and age at entry - was 1.85 (95% CI: 1.08-3.19). The observed joint RRs and attributable risks (ARs) across strata of three confounders were greater than the expected, indicating a positive interaction. Thus a history of PTB in current smokers may be another risk factor for lung cancer. Based on a synergic interaction, a heavy male smoker with a PTB history would be expected to belong to the group at high risk of lung cancer.