Comparative effectiveness and safety of ticagrelor and clopidogrel in patients with or without chronic liver disease: a nationwide cohort study

BACKGROUND

Although the effectiveness and safety of ticagrelor versus clopidogrel may differ in patients with chronic liver disease, there is a scarcity of evidence comparing ticagrelor and clopidogrel in patients with chronic liver disease. We aimed to evaluate the risk of major adverse cardiovascular events (MACE) and major bleeding associated with ticagrelor versus clopidogrel in patients undergoing percutaneous coronary intervention (PCI) due to acute coronary syndrome by chronic liver disease status.

METHODS

Using the Korean healthcare database, we included adult patients who underwent PCI and initiated ticagrelor or clopidogrel treatment within 7 days of an acute coronary syndrome diagnosis. Patients were divided into two mutually exclusive groups: patients with chronic liver disease and patients without chronic liver disease. Within each group, the hazard ratios (HRs) with 95% confidence intervals (CIs) of MACE and major bleeding associated with ticagrelor versus clopidogrel were calculated using a Cox proportional hazards model within a 1:1 propensity score (PS) matched cohort.

RESULTS

The final cohort included 14,261 and 148,535 patients with and without chronic liver disease, respectively. After PS matching, the risk of MACE (with chronic liver disease, HR: 1.01, 95% CI: 0.91-1.13; without chronic liver disease, HR: 1.02, 95% CI: 0.98-1.05; P for homogeneity: 0.865) and major bleeding (with chronic liver disease, HR: 1.07, 95% CI: 0.71-1.61; without chronic liver disease, HR: 1.32, 95% CI: 1.15-1.53; P for homogeneity: 0.342) for ticagrelor versus clopidogrel do not vary with chronic liver disease status.

CONCLUSIONS

Among acute coronary syndrome patients undergoing PCI, the use of ticagrelor versus clopidogrel was associated with a similar risk of MACE and an increased risk of major bleeding, but these risks did not vary with chronic liver disease status.

Population-Based Evaluation of Vaccine Effectiveness against SARS-CoV-2 Infection, Severe Illness, and Death, Taiwan

Taiwan provided several COVID-19 vaccine platforms: mRNA (BNT162b2, mRNA-1273), adenoviral vector-based (AZD1222), and protein subunit (MVC-COV1901). After Taiwan shifted from its zero-COVID strategy in April 2022, population-based evaluation of vaccine effectiveness (VE) became possible. We conducted an observational cohort study of 21,416,151 persons to examine VE against SARS-CoV-2 infection, moderate and severe illness, and death during March 22, 2021-September 30, 2022. After adjusting for age and sex, we found that persons who completed 3 vaccine doses (2 primary, 1 booster) or received MVC-COV1901 as the primary series had the lowest hospitalization incidence (0.04-0.20 cases/100,000 person-days). We also found 95.8% VE against hospitalization for 3 doses of BNT162b2, 91.0% for MVC-COV1901, 81.8% for mRNA-1273, and 65.7% for AZD1222, which had the lowest overall VE. Our findings indicated that protein subunit vaccines provide similar protection against SARS-CoV-2---associated hospitalization as mRNA vaccines and can inform mix-and-match vaccine selection in other countries.

Excess Mortality in Individuals with Autism Spectrum Disorder: A Population-Based Cohort Study

Purpose

Autism spectrum disorder (ASD) may be associated with increased mortality, but relevant findings have been inconsistent. The modifying effects of gender and intellectual disability on excess mortality in individuals with ASD are underexplored.

Patients and Methods

Using Taiwan's National Health Insurance Research Database and the National Death Registry, this population-based cohort study selected the data of 75,946 patients with ASD (ASD cohort) and 75,946 age group-, gender-, and income-matched (1:1) patients without ASD (non-ASD cohort). Cox proportional hazards models were used to compare mortality rates between the cohorts, and stratified analyses were used to evaluate the influence of gender and intellectual disability on mortality risk.

Results

The ASD cohort had higher mortality rates for all causes of death than did the non-ASD cohort (adjusted hazard ratio 1.64, 95% confidence interval 1.54-1.75). Comorbid intellectual disability was associated with an increased risk of mortality, and this association was stronger in female patients than in male patients. Moreover, when focusing on deaths from natural causes, we found a significantly higher odds ratio for mortality in the ASD population with ID compared to those without ID.

Conclusion

ASD is associated with increased mortality, especially among female individuals and those with intellectual disability.

Preterm children born below 33-35 weeks of gestation have an increased risk of mathematical difficulties

AIM

To investigate the association between gestational age (GA) and grade point averages by domains of language and mathematics at the end of lower secondary education.

METHODS

A nationwide register-based study including all Danish children born in 1992-1997 who completed lower secondary education. Grades were evaluated by GA. Domain-specific differences in grades were investigated, and academic profiles were made.

RESULTS

The study population comprised 319 796 children. For language, only minor differences in grades were observed. The grades in mathematics ranged from 7.02 (95% confidence interval [CI]: 7.00-7.04) at GA = 40 weeks to 5.86 (95% CI: 5.61-6.11) at GA <28 weeks. Grade differences showed lower grades in mathematics, compared to language, below GA 33-35 weeks. The academic profile of mathematical difficulties was more prevalent among GA <32 weeks. Average/high grades within both domains represented the predominant academic profile, constituting 68.8% at GA 39-41 weeks and 56.6% at GA <28 weeks.

CONCLUSION

Only in mathematics decreasing GA was associated with lower grades. Increased mathematical difficulties were found below GA 33-35 weeks. The academic profile of mathematical difficulties was more prevalent among GA <32 weeks. However, the absolute differences in grades were small, and the predominant academic profile was average/high grades within both domains across all GA.

Real-World Treatment Patterns, Clinical Outcomes, and Healthcare Resource Utilization in Early-Stage Non-Small-Cell Lung Cancer

The prognosis of early non-small-cell lung cancer (eNSCLC) remains poor. An understanding of current therapies and outcomes can provide insights into how novel therapies can be integrated into clinics. We conducted a large, retrospective, population-based cohort study of patients with de novo eNSCLC (stages IB, IIA, IIB, and IIIA) diagnosed in Alberta, Canada, between 2010 and 2019. The primary objectives were to describe treatment patterns and survival outcomes among patients with eNSCLC. A total of 5126 patients with eNSCLC were included. A total of 45.3% of patients were referred to a medical oncologist, ranging from 23.7% in stage IB to 58.3% in IIIA. A total of 23.6% of patients initiated systemic therapy (ST), ranging from 3.5% in stage IB to 38.5% in IIIA. For stage IIB and IIIA individuals who received surgery, adjuvant ST was associated with a decreased likelihood of death (hazard ratios (HR) of 0.77 (95% CI: 0.56-1.07) and 0.69 (95% CI: 0.54-0.89), respectively). In a Canadian real-world setting, stage IIB and IIIA patients who received adjuvant ST tended to have better survival than patients who did not, but future studies that provide adjustment of additional confounders are warranted. Examining referral pathways that account for disparities based on age, sex, and comorbidities in the real world would also provide further insights.

Incidence of Dermatitis Herpetiformis in Sweden 2005 to 2018: A Nationwide Retrospective Cohort Study

Dermatitis herpetiformis has been investigated in the past; however, only a limited number of studies have reported its incidence based on validated nationwide population-based registries. To address this gap, the aims of this study are to estimate the incidence of dermatitis herpetiformis in Sweden and to validate the National Patient Register (NPR) for diagnosis of dermatitis herpetiformis. A population-based open cohort study was conducted, including all patients diagnosed with dermatitis herpetiformis (International Classification of Diseases 10th revision; ICD-10 code L13.0) in Sweden from 2005 to 2018 (n = 1,724), identified from the NPR. The diagnosis of dermatitis herpetiformis in the NPR was validated using medical records, histopathological and immunopathological data, yielding a positive predictive value (PPV) of 62.5%. The mean annual incidence of dermatitis herpetiformis was 0.93/100,000 (95% confidence interval 0.79-1.08), female to male ratio 1:1, and mean age at diagnosis 60.9 years. In conclusion, this large nationwide cohort study showed a low validity for diagnosis of dermatitis herpetiformis in the NPR, and the adjusted incidence rate of dermatitis herpetiformis in Sweden was estimated to be 0.93/100,000, which is lower than that in previous Swedish studies.

Evaluation of the Risk Factors for Cellulitis among Patients with Peripheral Artery Disease

Background and objectives: The objective of this study is to elucidate peripheral occlusion artery disease (PAOD) as a risk factor for cellulitis. Materials and Methods: This is a retrospective population-based cohort study. The database is the Longitudinal Health Insurance Database, which covers two million beneficiaries from the entire population of the 2010 registry for beneficiaries in Taiwan. The PAOD group is composed of patients who were newly diagnosed with PAOD from 2001 to 2014. The non-PAOD group is composed of patients who were never diagnosed with PAOD from 2001 to 2015. All patients were followed until the onset of cellulitis, death, or until the end of 2015. Results: Finally, 29,830 patients who were newly diagnosed with PAOD were included in the PAOD group, and 29,830 patients who were never diagnosed with PAOD were included in the non-PAOD group. The incidence densities (ID) of cellulitis were 26.05 (95% CI = 25.31-26.80) patients per 1000 person-years in the PAOD group and 49.10 (95% CI = 48.04-50.19) in the non-PAOD group. The PAOD group had an increased risk of cellulitis (adjusted HR = 1.94, 95% CI = 1.87-2.01) compared to the non-PAOD group. Conclusions: Patients with PAOD were associated with a higher risk of subsequent cellulitis compared to patients without PAOD.

Multiparametric Prediction Models for Coronavirus Disease 2019 Vaccine Selection: Results of a Comparative Population-Based Cohort Study

BACKGROUND

An understanding vaccine-dependent effects on protective and sustained humoral immune response is crucial to planning future vaccination strategies against coronavirus disease 2019 (COVID-19).

METHODS

In this multicenter, population-based, cohort study including 4601 individuals after primary vaccination against COVID-19 ≥ 4 months earlier we compared factors associated with residual antibody levels against severe acute respiratory syndrome coronavirus-2 receptor-binding domain (RBD) across different vaccination strategies (BNT162b2, mRNA-1273, or ChAdOx1).

RESULTS

Our main model including 3787 individuals (2 × BNT162b2, n = 2271; 2 × mRNA-1273, n = 251; 2 × ChAdOx1, n = 1265), predicted significantly lower levels of anti-RBD antibodies after 6 months in individuals vaccinated with ChAdOx1 (392.7 binding antibody units per milliliter [BAU/mL]) compared with those vaccinated with BNT162b2 (1179.5 BAU/mL) or mRNA-1273 (2098.2 BAU/mL). Vaccine-dependent association of antibody levels was found for age with a significant predicted difference in BAU/ml per year for BNT162b2 (-21.5; 95% confidence interval [CI], -24.7 to -18.3) and no significant association for mRNA-1273 (-4.0; 95% CI, -20.0 to 12.1) or ChAdOx1 (1.7; 95% CI, .2 to 3.1). The predicted decrease over time since full immunization was highest in mRNA-1273 (-23.4; 95% CI, -31.4 to -15.4) compared with BNT162b2 (-5.9; 95% CI, -7 to -4.8).

CONCLUSIONS

Our study revealed population-based evidence of vaccine-dependent effects of age and time since full immunization on humoral immune response. Findings underline the importance of individualized vaccine selection, especially in elderly individuals.

The association between smoking, changes in smoking behavior, and acute pancreatitis: A population-based cohort study in Korea

BACKGROUND AND AIMS

In the Asian population, existing studies regarding the association between smoking and acute pancreatitis are few in number. The aim of this study was to investigate the incidence of acute pancreatitis according to smoking habits and smoking habit changes of the Korean population.

METHODS

We used clinical data from individuals (aged 20 years or older) who received health examinations arranged by the Korean National Health Insurance Service in 2009 (n = 4 238 822) or in 2009 and 2011 (n = 2 617 306). The incidence of acute pancreatitis was analyzed according to smoking status or smoking habit change reported by individuals during their health examination. Newly diagnosed acute pancreatitis was identified using claims data from baseline to the date of diagnosis or until December 31, 2018.

RESULTS

The risk of acute pancreatitis was significantly higher in current smokers compared with never-smokers regardless of age or sex. The adjusted hazard ratio (HR) of acute pancreatitis in current smokers increased according to the amount of smoking (HR 1.28; 95% confidence interval [CI], 1.12-1.45 in <10 cigarettes/day, HR 1.4; CI, 1.3-1.52 in 10-19 cigarettes/day, HR 1.66; CI, 1.55-1.78 in ≥20 cigarettes/day). The adjusted HR of acute pancreatitis in continuous smokers was 1.66 (CI, 1.53-1.8) compared with never-smokers and was higher than smokers who quit smoking (HR 1.34; CI, 1.17-1.54).

CONCLUSIONS

In this Korean population-based cohort study, smoking increased the incidence of acute pancreatitis in a dose-dependent manner, and smoking cessation helped decrease the incidence of acute pancreatitis.

Body Mass Index Measured Repeatedly over 42 Years as a Risk Factor for Ischemic Stroke: The HUNT Study

BACKGROUND

Higher BMI in middle age is associated with ischemic stroke, but little is known about BMI over adulthood, and the risk for ischemic stroke as most studies relied on a single measurement of BMI.

METHODS

BMI was measured four times over a period of 42 years. We calculated average BMI values and group-based trajectory models and related these to the prospective risk of ischemic stroke after the last examination in Cox models with a follow-up time of 12 years.

RESULTS

A total of 14,139 participants, with a mean age of 65.2 years and 55.4% women, had information on BMI from all four examinations, and we observed 856 ischemic strokes. People with overweight and obesity over adulthood had a higher risk for ischemic stroke with a multivariable-adjusted hazard ratio of 1.29 (95% CI 1.11-1.48) and 1.27 (95% CI 0.96-1.67), respectively, when compared to normal weight participants. Excess weight tended to have stronger effects earlier than later in life. A trajectory of developing obesity throughout life was associated with higher risk than other trajectories.

CONCLUSIONS

High average BMI, especially at an early age, is a risk factor for ischemic stroke. Early weight control and long-term weight reduction for those with high BMI may decrease the later occurrence of ischemic stroke.

The use of Chinese herbal medicines throughout the pregnancy life course and their safety profiles: a population-based cohort study

BACKGROUND

Chinese herbal medicines have been long used among pregnant populations in China. However, despite the high susceptibility of this population to drug exposure, it continued to remain unclear about how often they were used, to what extent they were used at different pregnancy stages, and whether their use was based on sound safety profiles, particularly when used in combination with pharmaceutical drugs.

OBJECTIVE

This descriptive cohort study aimed to systematically investigate the use of Chinese herbal medicines throughout pregnancy and their safety profiles.

STUDY DESIGN

A large medication use cohort was developed by linking a population-based pregnancy registry and a population-based pharmacy database, which documented all prescriptions at both outpatients and inpatients from conception to 7 days after delivery, including pharmaceutical drugs and processed Chinese herbal medicine formulas that were approved by the regulatory authority and prepared under the guidance of national quality standards. The prevalence of the use of Chinese herbal medicine formulas, prescription pattern, and combination use of pharmaceutical drugs throughout pregnancy were investigated. Multivariable log-binomial regression was performed to assess temporal trends and further explore the potential characteristics associated with the use of Chinese herbal medicines. Of note, 2 authors independently conducted a qualitative systematic review of patient package inserts of the top 100 Chinese herbal medicine formulas used to identify their safety profiles.

RESULTS

This study included 199,710 pregnancies; of those pregnancies, 131,235 (65.71%) used Chinese herbal medicine formulas, including 26.13% during pregnancy (corresponding to 14.00%, 8.91%, and 8.26% in the first, second, and third trimesters of pregnancy) and 55.63% after delivery. The peak uses of Chinese herbal medicines occurred between 5 and 10 weeks of gestation. The use of Chinese herbal medicines significantly increased over the years (from 63.28% in 2014 to 69.59% in 2018; adjusted relative risk, 1.11; 95% confidence interval, 1.10-1.13), which was particularly great during pregnancy (from 18.47% in 2014 to 32.46% in 2018; adjusted relative risk, 1.84; 95% confidence interval, 1.77-1.90). Our study observed 291,836 prescriptions involving 469 Chinese herbal medicine formulas, and the top 100 most used Chinese herbal medicines accounted for 98.28% of the total prescriptions. Of those, a third (33.39%) were dispensed at outpatient visits; 6.79% were external use, and 0.29% were administered intravenously. However, Chinese herbal medicines were very often prescribed in combination with pharmaceutical drugs (94.96% overall), involving 1175 pharmaceutical drugs with 1,667,459 prescriptions. The median of pharmaceutical drugs prescribed in combination with Chinese herbal medicines per pregnancy was 10 (interquartile range, 5-18). The systematic review of drug patient package inserts found that the 100 most frequently prescribed Chinese herbal medicines contained a total of 240 herb constituents (median, 4.5); 7.00% were explicitly indicated for pregnancy or postpartum conditions; 43.00% were reported with efficacy or safety data from randomized controlled trials. Information was lacking about whether the medications had any reproductive toxicity, were excreted in human milk, or crossed the placenta.

CONCLUSION

The use of Chinese herbal medicines was prevalent throughout pregnancy and increased over the years. The use of Chinese herbal medicines peaked in the first trimester of pregnancy and was very often used in combination with pharmaceutical drugs. However, their safety profiles were mostly unclear or incomplete, suggesting a strong need for postapproval surveillance for the use of Chinese herbal medicines during pregnancy.

Risk factors and drugs that trigger the onset of Stevens-Johnson syndrome and toxic epidermal necrolysis: A population-based cohort study using the Shizuoka Kokuho database

Background

Evidence of factors associated with Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) from population-based studies is scarce.

Objective

We aimed to identify the incidence, risk factors, and drugs that trigger the development of SJS/TEN in the general population.

Methods

A regional, population-based, longitudinal cohort with 2,398,393 Japanese individuals was analyzed using the Shizuoka Kokuho Database from 2012 to 2020.

Results

Among 1,909,570 individuals, 223 (0.01%, 2.3 cases/100,000 person-years) patients were diagnosed with SJS/TEN during the observational period of a maximum of 7.5 years. In a multivariable analysis, the risks of SJS/TEN were an older age, and the presence of type 2 diabetes, peripheral vascular disease, and systemic autoimmune diseases. The administration of drugs, such as immune checkpoint inhibitors, insulin, and type 2 diabetes agents, triggered the onset of SJS/TEN.

Limitations

The results may apply only to the Japanese population.

Conclusion

In this cohort population from a database representing the general population, the risks of developing SJS/TEN were old age and a history of type 2 diabetes, peripheral vascular disease, and systemic autoimmune disease. Furthermore, in addition to previously reported drugs, the administration of immune checkpoint inhibitors, insulin, and type 2 diabetes agents, may trigger the development of SJS/TEN.

Risk of colorectal cancer after use of fertility drugs-results from a large Danish population-based cohort of women with infertility

OBJECTIVE

To study the association between use of fertility drugs and colorectal cancer among women with infertility.

DESIGN

Population-based cohort study.

SETTING

Not applicable.

PATIENT(S)

The study cohort was obtained from the Danish Infertility Cohort and consisted of all women with infertility aged 20-45 years living in Denmark during 1995-2017.

INTERVENTION(S)

Information on the use of specific types of fertility drugs, colorectal cancer diagnoses, covariates, and vital status were obtained from the Danish Infertility Cohort and Danish national registers.

MAIN OUTCOME MEASURE(S)

Cox proportional hazard models adjusted for potential confounders were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for colorectal cancer overall and rectal and colon cancer separately.

RESULTS(S)

Among 148,036 women in the final study cohort, 205 women were diagnosed with colorectal cancer. Ever use of clomiphene citrate (CC) was associated with a lower rate of colorectal cancer (unadjusted HR, 0.67; 95% CI, 0.51-0.89; adjusted HR, 0.68; 95% CI, 0.50-0.93). However, the lower rate was only seen among women who first used CC >8 years ago (unadjusted HR, 0.56; 95% CI, 0.41-0.76; adjusted HR, 0.52; 95% CI, 0.36-0.75). No marked associations were found between the use of any of other types of fertility drugs and colorectal cancer. The results for colon and rectal cancer analyzed separately were similar, except for a suggestion of a decreased risk of rectal cancer associated with the use of gonadotropins (adjusted HR, 0.46; 95% CI, 0.20-1.08).

CONCLUSION(S)

Among women with infertility, the use of most types of fertility drugs was not associated with colorectal cancer. However, CC may decrease the risk of colorectal cancer and gonadotropins might decrease the risk of rectal cancer, but we cannot rule out that these findings may be more related to the underlying conditions in these women or are chance findings. Consequently, the results from this study should be investigated further in large epidemiological studies.

Population-Based Assessment of Determining Predictors for Discharge Disposition in Patients with Bladder Cancer Undergoing Radical Cystectomy

Objective: To assess predictors of discharge disposition—either home or to a CRF—after undergoing RC for bladder cancer in the United States. Methods: In this retrospective, cohort study, patients were divided into two cohorts: those discharged home and those discharged to CRF. We examined patient, surgical, and hospital characteristics. Multivariable logistic regression models were used to control for selected variables. All statistical tests were two-sided. Patients were derived from the Premier Healthcare Database. International classification of disease (ICD)-9 (<2014), ICD-10 (≥2015), and Current Procedural Terminology (CPT) codes were used to identify patient diagnoses and encounters. The population consisted of 138,151 patients who underwent RC for bladder cancer between 1 January 2000 and 31 December 2019. Results: Of 138,151 patients, 24,922 (18.0%) were admitted to CRFs. Multivariate analysis revealed that older age, single/widowed marital status, female gender, increased Charlson Comorbidity Index, Medicaid, and Medicare insurance are associated with CRF discharge. Rural hospital location, self-pay status, increased annual surgeon case, and robotic surgical approach are associated with home discharge. Conclusions: Several specific patient, surgical, and facility characteristics were identified that may significantly impact discharge disposition after RC for bladder cancer.

Associations of sleep timing and time in bed with dementia and cognitive decline among Chinese older adults: A cohort study

BACKGROUND

The longitudinal associations of sleep timing and time in bed (TIB) with dementia and cognitive decline in older adults are unclear.

METHODS

This population-based cohort study used data from 1982 participants who were aged ≥60 years, free of dementia, and living in rural communities in western Shandong, China. At the baseline (2014) and follow-up (2018) examinations, sleep parameters were assessed using standard questionnaires. Cognitive function was measured using the Mini-Mental State Examination (MMSE). Dementia was diagnosed following the DSM-IV criteria, and the NIA-AA criteria for Alzheimer disease (AD). Data were analyzed using restricted cubic splines, Cox proportional-hazards models, and general linear models.

RESULTS

During the mean follow-up of 3.7 years, dementia was diagnosed in 97 participants (68 with AD). Restricted cubic spline curves showed J-shaped associations of sleep duration, TIB, and rise time with dementia risk, and a reverse J-shaped association with mid-sleep time. When sleep parameters were categorized into tertiles, the multivariable-adjusted hazard ratio (HR) of incident dementia was 1.69 (95%CI 1.01-2.83) for baseline sleep duration >8 hours (vs. 7-8 h), 2.17 (1.22-3.87) for bedtime before 9 p.m. (vs. 10 p.m. or later), and 2.00 (1.23-3.24) for mid-sleep time before 1 a.m. (vs. 1-1.5 a.m.). Early bedtime and mid-sleep time were significantly associated with incident AD (HR range: 2.25-2.51; p < 0.05). Among individuals who were free of dementia at follow-up, baseline long TIB, early bedtime and mid-sleep time, early and late rise time, and prolonged TIB and advanced bedtime and mid-sleep time from baseline to follow-up were associated with a greater decline in MMSE score (p < 0.05). These associations with cognitive decline were statistically evident mainly among men or participants who were aged 60-74 years.

CONCLUSIONS

Long TIB and early sleep timing are associated with an increased risk of dementia, and the associations with greater cognitive decline are evident only among older people aged 60-74 years and men.

Effects of Exposure Duration and Exposure Levels of Ambient Air Pollutants on the Risk of Polycystic Ovarian Syndrome: A 2015-2019 Korean Population-Based Cohort Study

Exposure to ambient air pollution is associated with an increased risk of menstrual disorders and infertility. This study examined the relationships between the levels and duration of air pollution exposure and the risk of polycystic ovarian syndrome (PCOS) using Korean population-based cohort data (2015-2019). Real-time data on PM₁₀, PM_2.5, O₃, CO, SO₂, and NO₂ were provided by the Korean Ministry of Environment. The average monthly air pollutant concentration from 1 January 2014 to 31 December 2018 was analyzed. To assess individual-level exposure to air pollutants, a spatial prediction model and an area-averaging approach were used. In total, 237,582 PCOS cases were analyzed. The annual age-adjusted PCOS incidence was 6.70, 8.28, 9.73, 11.58, and 11.97% from 2015-2019, respectively. The PCOS risk increased 1.29-1.32, 1.43-1.52, and 1.32-fold following exposure to the 2-year and 3-year average levels of PM_2.5, O₃, and NO₂, respectively, compared to their 1-year average levels. The PCOS risk increased 1.75-fold (95% confidence interval: 1.66-1.85) in the fourth-quartile for the NO₂ level. Increased SO₂ and CO levels in the second- and third-quartiles were also associated with an increased PCOS risk. Exposure to air pollutants thus increased the risk for PCOS in the Korean population.

Little evidence for long-term harm from antenatal corticosteroids in a population-based very low birthweight young adult cohort

BACKGROUND

Antenatal corticosteroids (ACS) given to mothers with anticipated very preterm delivery are widely used and improve infant outcomes. Follow-up studies of the first trials of ACS have shown no adverse effects, but recently there have been concerns about possible longer-term harms.

OBJECTIVES

We aimed to assess the relationship of ACS therapy to a range of physical health and welfare measures in a cohort of very low birthweight (VLBW; <1500 g) young adults.

METHODS

Population-based cohort follow-up study. All VLBW infants born in New Zealand in 1986 were included in a prospective audit of retinopathy of prematurity. Perinatal data collection included information on ACS. At 26-30 years, 250 of 323 (77%) survivors participated, 58% having received ACS, with 229 assessed in one centre, including cardiovascular, metabolic, respiratory and neurocognitive measures. Differences in outcome between those receiving/not receiving ACS were summarised by the mean difference for continuous outcomes supplemented by Cohen's d as a standardised measure of effect size (ES), and risk ratios (RRI) for dichotomous outcomes, adjusted for relevant covariates using generalised linear regression methods.

RESULTS

There were no or minimal adverse effects of receipt of ACS versus no receipt across a range of health and welfare outcomes, both for the full cohort (adjusted ES range d = 0.01-0.23; adjusted RR range 0.78-2.03) and for individuals with gestation <28 weeks (extremely preterm; EP), except for a small increase in rates of major depression. In EP adults, receipt of ACS was associated with a higher incidence of hypertension, but might have a small benefit for IQ.

CONCLUSIONS

In this population-based VLBW cohort, we detected minimal adverse outcomes associated with exposure to ACS by the third decade of life, a similar result to the 30-year follow-up of participants in the first ACS trial. However, further follow-up is warranted.

Risk of dialysis in patients receiving intravitreal anti-vascular endothelial growth factor treatment: a population-based cohort study

We utilized the Longitudinal Health Insurance Database which was stemmed from the Taiwan's National Health Insurance Research Database to conduct a retrospective cohort study investigating the risk of becoming dialysis dependent after receiving intravitreal anti-vascular endothelial growth factor (VEGF) agents for retinal diseases. Patients newly receiving intravitreal ranibizumab or aflibercept from 2000 to 2017 for age-related macular degeneration, polypoidal choroidal vasculopathy, diabetic macular edema, retinal vein occlusions, or myopic choroid neovascularization were included as the study group, and patients with same retinal diseases but did not receive intravitreal anti-VEGFs served as controls extracted by age- and sex-matched (1:4) and further propensity score matching (PSM). Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the risk of dialysis. A cohort of 2447 anti-VEGF users and 2447 controls by PSM were evaluated. Higher dialysis risks were observed among patients newly receiving anti-VEGF agents compared to controls (adjusted HR: 1.849; 95% CI: 1.378–2.482) in the PSM cohort. For subgroup analysis, patients newly receiving anti-VEGF treatment for diabetic macular edema had significant risk (adjusted HR: 1.834; 95% CI: 1.448–2.324) of becoming dialysis-dependent, while patients in other subgroups demonstrated similar risks as the controls. In conclusion, intravitreal anti-VEGF agents might increase the risk of becoming dialysis-dependent, especially in patients who are treated for diabetic macular edema.

Cardiometabolic multimorbidity accelerates cognitive decline and dementia progression

INTRODUCTION

Cardiometabolic diseases (CMDs) have been individually associated with adverse cognitive outcomes, but their combined effect has not been investigated.

METHODS

A total of 2577 dementia-free participants 60 years of age or older were followed for 12 years to observe changes in cognitive function and to detect incident cognitive impairment, no dementia (CIND) and dementia. CMDs (including type 2 diabetes, heart disease, and stroke) were assessed at baseline through medical records and clinical examinations. Cardiometabolic multimorbidity was defined as the presence of two or more CMDs. Data were analyzed using multi-adjusted linear mixed-effects models, Cox regression, and Laplace regression.

RESULTS

CMD multimorbidity was associated with cognitive decline, CIND (hazard ratio [HR] 1.73; 95% confidence interval CI 1.23 to 2.44), and its progression to dementia (HR 1.86; 95% CI 1.17 to 2.97). CMD multimorbidity accelerated the onset of CIND by 2.3 years and dementia by 1.8 years.

CONCLUSIONS

CMD multimorbidity accelerates cognitive decline and increases the risk of both CIND and its conversion to dementia.

HIGHLIGHTS

We explored the combined impact of cardiometabolic diseases (CMDs) on cognition. An increasing number of CMDs dose-dependently accelerated cognitive decline. CMD multimorbidity increased the risk of both cognitive impairment and dementia. Co-morbid CMDs could be ideal targets for interventions to protect cognitive health.

Revisiting the Association Between Inflammatory Bowel Disease and Parkinson's Disease

BACKGROUND

Several studies have reported an association between inflammatory bowel disease (IBD) and Parkinson's disease (PD). The aim of this study is to re-evaluate for an association between IBD and PD while controlling for potential socioeconomic and environmental confounders.

METHODS

We performed a retrospective cohort study using the Truven Health Marketscan database between January 1, 2005, and December 31, 2014. Individuals with IBD and household age-matched controls were identified. Adjusted hazard ratios (HRs) were calculated for the development of incident PD, adjusting for age, sex, residence type, US region, comorbidities, and behavior.

RESULTS

In all, 154 051 subjects with IBD and an equal number of controls were identified. During a mean (SD) follow-up of 3.8 (2.2) years, 132 incident PD cases were identified. There was no significant association between IBD and PD (adjusted HR, 1.01; 0.72-1.42) when adjusting for the confounders previously mentioned.

CONCLUSIONS

We found no statistically significant association between these disorders. It is possible that previous associations identified between these disorders were confounded by environmental and socioeconomic factors.

Human Gut Antibiotic Resistome and Progression of Diabetes

The antibiotic resistance crisis underlies globally increasing failures in treating deadly bacterial infections, largely due to the selection of antibiotic resistance genes (ARG) collection, known as the resistome, in human gut microbiota. So far, little is known about the relationship between gut antibiotic resistome and host metabolic disorders such as type 2 diabetes (T2D). Here, metagenomic landscape of gut antibiotic resistome is profiled in a large multiomics human cohort (n = 1210). There is a significant overall shift in gut antibiotic resistome structure among healthy, prediabetes, and T2D groups. It is found that larger ARG diversity is associated with a higher risk of T2D. The novel diabetes ARG score is positively associated with glycemic traits. Longitudinal validation analysis confirms that the ARG score is associated with T2D progression, characterized by the change of insulin resistance. Collectively, the data describe the profiles of gut antibiotic resistome and support its close relationship with T2D progression.

A long-term nationwide population-based cohort study

OBJECTIVE

Ankylosing spondylitis (AS) is a chronic inflammatory disease, might carry a high risk of irritable bowel syndrome (IBS) due to abnormal gut microbiota or inflammatory reaction.

METHODS

We conducted a 14-year retrospective cohort study based on Taiwan's National Health Insurance Research Database (NHIRD). A total of 4007 patients with newly diagnosed AS (outpatient visits≧3 times, or hospitalization≧1 time) and 988,084 non-AS comparisons were enrolled during 2000-2012. To ensure baseline comparability, the propensity score was matched by age, gender, comorbidities, and other possible confounders. The outcome was the incidence of IBS, followed up to the end of 2013. Cox proportional hazard model calculated adjusted hazard ratio (aHR) and the cumulative incidence of both groups was analyzed by the Kaplan-Meier method.

RESULT

After propensity score matching, baseline demographic characteristics were comparable between AS patients and the comparison group. The crude HR for IBS in the AS group was significantly higher 2.41 (95%C.I. =1.84-3.16) than comparison group. After adjusting for possible confounders, adjusted HR was 2.50 (95%C.I.=1.91-3.29). The cumulative incidence of IBS in AS was significantly higher than non-AS comparisons during the 14-year follow-up (P<0.001).

CONCLUSION

This nationwide population-based cohort study showed that patients with AS have higher risks of IBS than those of the non-AS comparison group.

Incidence and Predictors of Prosthetic Joint Infection Following Primary Total Knee Arthroplasty: A 15-Year Population-Based Cohort Study

BACKGROUND

One of the most devastating complications of total knee arthroplasty (TKA) is periprosthetic joint infection (PJI). Although many complications associated with TKA have decreased over time, the trends associated with PJI are less clear. Thus, the purpose of this study is to determine the incidence and risk factors for PJI after primary TKA.

METHODS

We performed a population-based cohort study using linked administrative databases in Ontario, Canada. We used a Cox proportional hazards model to analyze the effect of surgical factors and patient factors on the risk of developing PJI.

RESULTS

In total, 129,613 patients aged 50+ received a primary TKA for osteoarthritis from 2002 to 2016 in Ontario, Canada. In total, 1.41% of patients underwent revision surgery for PJI. When accounting for censoring, the cumulative incidence for PJI was 0.51% (95% confidence interval 0.46-0.55) at 1 year, 1.12% (1.05-1.18) at 5 years, 1.49% (1.41-1.57) at 10 years, and 1.65% (1.55-1.75) at 15 years. The multivariable model revealed that male gender, younger age, type II diabetes, post-traumatic arthritis, patellar resurfacing, and discharge to convalescent care were associated with increased risk of PJI.

CONCLUSION

The risk of PJI following TKA has decreased in small but steady increments over the past 15 years. Most PJIs are diagnosed within the first 2 years postoperatively, though a small group do continue to occur after 10 years. Overall, while the incidence of PJI has decreased slightly over the past 15 years, it remains among the most concerning complications of TKA and continued efforts aimed at further reducing its occurrence are needed.

Prevalent migraine as a predictor of incident hypertension

Background

Migraine has been associated with several diseases. This population-based prospective Finnish postal survey Health and Social Support Study explored whether self-reported migraine predicted incident hypertension independently in a working-age population by utilizing two data sources: the baseline survey from the year 1998 in combination with the follow-up survey data from the years 2003 and 2012 with linkage to the national Social Insurance Institution registry data of the special reimbursement medication for hypertension from 1999 to 2013. The survey follow-up reached until the second follow-up in the year 2012. The register follow-up also included the year 2013.

Methods

The present population-based prospective cohort study, utilizing two different data sources, included 8593 respondents (22.7% response rate) who participated in 1998, 2003, and 2012 but who did not report hypertension at the baseline in 1998, and whose responses could be linked with the Social Insurance Institution registry data from the beginning of 1999 to the end of 2013. The multivariable logistic regression analysis was based on the combined two data sets.

Results

A significant association of self-reported migraine and incident hypertension (odds ratio 1.37; 95% confidence interval 1.20–1.57) prevailed in the multiple logistic regression analysis adjusted for central socio-demographic and health behaviour variables.

Conclusion

Extra attention should be paid to prevention and control of hypertension in working-age migraine patients.

Fertility drugs and incidence of thyroid cancer in a Danish nationwide cohort of 146 024 infertile women

STUDY QUESTION

Do fertility drugs increase the risk of thyroid cancer among infertile women?

SUMMARY ANSWER

The use of most types of fertility drugs was not associated with an increased risk of thyroid cancer.

WHAT IS KNOWN ALREADY

The incidence of thyroid cancer is higher for women than men, especially during reproductive years, indicating that reproductive hormones may be involved in the development of thyroid cancer. Only a few previous studies have examined the association between the use of fertility drugs and incidence of thyroid cancer and the results are inconclusive.

STUDY DESIGN, SIZE, DURATION

A retrospective, population-based cohort study including all 146 024 infertile women aged 20-45 years and living in Denmark in the period 1995-2017. The women were followed from the date of entry in the cohort (i.e. date of first infertility diagnosis) until the occurrence of thyroid cancer or any other cancer (except non-melanoma skin cancer), death, emigration, total thyroidectomy or the end of follow-up (31 December 2018), whichever occurred first. The median length of follow-up was 11.3 years.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In total, 167 women were diagnosed with thyroid cancer during the follow-up period. Information on the use of specific fertility drugs (clomiphene citrate, gonadotropins, hCGs, GnRH receptor modulators and progesterone), thyroid cancer, covariates and vital status was obtained from the Danish Infertility Cohort and various Danish national registers. Cox proportional hazard regression models were used to calculate hazard ratios (HRs) and 95% CIs for thyroid cancer overall and for papillary thyroid cancer.

MAIN RESULTS AND THE ROLE OF CHANCE

After adjustment for the calendar year of infertility diagnosis, the highest obtained level of education, parity status, obesity or thyroid disease and mutual adjustment for other registered fertility drugs, no marked associations were observed between the use of clomiphene citrate, hCG, gonadotropins or GnRH receptor modulators and risk of overall or papillary thyroid cancer. However, ever use of progesterone was associated with an increased rate of both overall (HR 1.63; 95% CI 1.07-2.48) and papillary (HR 1.66, 95% CI 1.04-2.65) thyroid cancer after mutual adjustment for other specific fertility drugs. For most specific fertility drugs, we observed a tendency toward higher associations with thyroid cancer within the first 5 years after the start of drug use than after 5 years from the start of use. No marked associations were detected according to the cumulative dose for any of the specific fertility drugs.

LIMITATIONS, REASONS FOR CAUTION

Despite a large study population, the statistical precision in some subgroup analyses may be affected due to the low number of thyroid cancer cases. Although we were able to adjust for a number of potential confounders, residual and unmeasured confounding may potentially have affected the observed associations, as we could not adjust for some factors that may influence the association between fertility drugs and thyroid cancer, including age at menarche and BMI.

WIDER IMPLICATIONS OF THE FINDINGS

Although this study, which is the largest to date, provides reassuring evidence that there is no strong link between the use of fertility drugs and thyroid cancer incidence, we observed a modest increased thyroid cancer incidence after the use of progesterone. However, we cannot rule out that this is a chance finding and the potential association between the use of progesterone and thyroid cancer should therefore be investigated further in large epidemiological studies. The results of the present study provide valuable knowledge for clinicians and other health care personnel involved in the diagnosis and treatment of infertility.

STUDY FUNDING/COMPETING INTEREST(S)

The study was supported by research grants from the Jascha Foundation and the Aase and Ejner Danielsens Foundation. B.N. received honoraria and/or non-financial support by Gedeon Richter Nordics AB, IBSA Nordic APS and Merck KGAA. The remaining authors have no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Implications of metabolic health status and obesity on the risk of kidney cancer: A nationwide population-based cohort study

PURPOSE

This study evaluated the association between metabolic health status and incident kidney cancer among obese participants.

MATERIALS AND METHODS

A total of 514,866 individuals were included from the Korean National Health Insurance Service-National Health Screening Cohort. Changes in metabolic health status and obesity from the baseline examination in 2009-2010 to the next biannual examination in 2011-2012 were determined. Based on the status change, obese participants were divided into four groups: stable metabolically healthy obesity, metabolically healthy obesity to metabolically unhealthy obesity, metabolically unhealthy obesity to metabolically healthy obesity, and stable metabolically unhealthy obesity.

RESULTS

The stable metabolically healthy obesity phenotype did not confer an increased risk of incident kidney cancer, compared to the stable metabolically healthy non-obese group. In contrast, the metabolically healthy obesity to metabolically unhealthy obesity group had a significantly higher risk of incident kidney cancer than the stable metabolically healthy non-obese group. Among patients with metabolically unhealthy obesity at baseline, those who transitioned to the metabolically healthy obese group had no increased risk of kidney cancer, whereas those who remained in metabolically unhealthy obesity status had a higher risk of incident kidney cancer than the stable metabolically healthy non-obese group. The transition or maintenance of metabolic health was a decisive factor for kidney cancer in obese patients.

CONCLUSIONS

Maintaining or restoring metabolic health should be stressed upon in obese patients to reduce the risk of kidney cancer.

Proton pump inhibitor use and hearing loss in patients with type 2 diabetes: evidence from a hospital-based case-control study and a population-based cohort study

OBJECTIVES

This study aimed to investigate the association between proton pump inhibitor (PPI) use and risk of sensorineural hearing loss (SNHL) or tinnitus in patients with type 2 diabetes using hospital- and population-based data.

METHODS

For the case-control study using the Asan biomedical research environment (ABLE) database, the characteristics between cases and sex-, age-, and index-year-matched controls were compared by the chi-squared test. Conditional logistic regression was used to estimate the odds ratios (ORs). For the cohort study using the Korean National Health Insurance Service-National Sample Cohort, the hazard ratios (HRs) for SNHL or tinnitus associated with PPI use were analyzed by the Cox proportional hazard regression model.

RESULTS

The case-control study included 1,379 cases and 5,512 matched controls. After adjustment, PPI use was associated with an increased risk of SNHL or tinnitus (OR: 1.61, 95% CI: 1.30-1.99). The ORs were higher for current or recent use of PPI and high average daily dose. In the cohort study including 17,233 pairs of PPI users and non-users after propensity score matching, the risk of SNHL or tinnitus increased in PPI users compared with non-users (HR: 1.50, 95% CI: 1.40-1.61). In the stratified analyses, risks remained significant, and the magnitude of association was relatively high in those of younger age, patients without gastroesophageal reflux disease, and patients not receiving histamine 2 receptor blockers.

CONCLUSIONS

Our study suggests that PPI use is associated with an increased risk of SNHL or tinnitus. Given the widespread use of PPIs, the potential ototoxic effects of PPIs remain an important concern.

Characterization of gut microbial structural variations as determinants of human bile acid metabolism

Bile acids (BAs) facilitate intestinal fat absorption and act as important signaling molecules in host-gut microbiota crosstalk. BA-metabolizing pathways in the microbial community have been identified, but it remains largely unknown how the highly variable genomes of gut bacteria interact with host BA metabolism. We characterized 8,282 structural variants (SVs) of 55 bacterial species in the gut microbiomes of 1,437 individuals from two cohorts and performed a systematic association study with 39 plasma BA parameters. Both variations in SV-based continuous genetic makeup and discrete clusters showed correlations with BA metabolism. Metagenome-wide association analysis identified 809 replicable associations between bacterial SVs and BAs and SV regulators that mediate the effects of lifestyle factors on BA metabolism. This is the largest microbial genetic association analysis to demonstrate the impact of bacterial SVs on human BA composition, and it highlights the potential of targeting gut microbiota to regulate BA metabolism through lifestyle intervention.

Associations Between the Metabolic Score for Insulin Resistance Index and the Risk of Type 2 Diabetes Mellitus Among Non-Obese Adults: Insights from a Population-Based Cohort Study

Purpose

The metabolic score for insulin resistance (METS-IR) index is an emerging surrogate predictor of type 2 diabetes mellitus (T2DM). This study aimed to evaluate the association between the METS-IR index and the risk of T2DM in non-obese Japanese adults.

Methods

A total of 12,290 non-obese participants were selected from the NAGALA prospective cohort study conducted from 2004 to 2015. Cox proportional hazards models were used to assess the association between the baseline METS-IR index and risk of T2DM. Generalized additive models were used to identify nonlinear relationships. In addition, we performed subgroup analyses and interaction tests. Results were expressed as hazard ratios (HRs) and 95% confidence intervals (CIs).

Results

During a median follow-up of 2050 days, 176 (1.43%) incident T2DM occurred. The fully adjusted HR (95% CI) for the incidence of T2DM in non-obese adults was 1.17 (HR=1.17, 95% CI: 1.09–1.27, P<0.001) for every 1-unit increase in the METS-IR index. The risk of developing T2DM increased with the quartile of change in the METS-IR index, after adjustment for multiple potential confounding, the HRs for the Q4 group versus the Q1 group was 4.01 (95% CI, 1.39–11.57). Generalized additive models also showed a cumulative increase in the risk of T2DM with increasing the METS-IR index. Time-dependent receiver operating curve suggested helpful discriminative power of the METS-IR index for T2DM. The C-statistics by the clinical risk factors significantly improve with the addition of the METS-IR index (from 0.862 to 0.875, P = 0.035); the discriminatory power and risk reclassification also appeared to be substantially better, with the category-free NRI of 0.216, and the IDI of 0.011.

Conclusion

The METS-IR index was a significant and independent predictor for future T2DM development in non-obese adults. The METS-IR index may have clinical significance in identifying groups at high risk of T2DM.

Association Between Subconjunctival Hemorrhage and Acute Coronary Syndrome: A 14-Year Nationwide Population-Based Cohort Study

Purpose: Subconjunctival hemorrhage (SCH) is usually a benign ocular disorder that causes painless, redness under the conjunctiva. However, since SCH and acute coronary syndrome (ACS) share many vascular risk factors, studies have suggested that these two disorders may be significantly associated with each other, and evaluate the concomitance of ACS in patients with SCH.

Methods: This population-based cohort study, enrolled 35,260 Taiwanese patients, and used the Taiwan National Health Insurance Research Database to identify patients with ACS and SCH. Outcomes were compared between the with and without SCH groups. The study population was followed until the date of ACS onset, the date of withdrawal, death, or December 31st 2013, whichever came first.

Results: Of the 85,925 patients identified with SCH between 1996 and 2013, 68,295 were excluded based on the study's exclusion criteria, and a total of 17,630 patients with SCH who were diagnosed by ophthalmologists between 2000 and 2012 were eligible for analysis. After 1:1 propensity score matching for 5-year age groups, gender, and the index year, the results showed that SCH was more common in the 40–59 age group (53.82%) and females (58.66%). As for the ACS-related risk factors, patients with diabetes mellitus (aHR = 1.58, 95% CI = [1.38, 1.81]), hypertension (aHR = 1.71, 95% CI = [1.49, 1.96]) and patients taking aspirin (aHR = 1.67, 95% CI = [1.47, 1.90]) had a notably higher risk of ACS. However, it was found that there were no significant differences in the occurrence of ACS between the non-SCH and SCH patients.

Conclusion: This results of this study regarding the risk factors and epidemiology of SCH and ACS were in keeping with previously reported findings. However, the results revealed no significant association between SCH and ACS.

The impact of diabetes on cognitive impairment and its progression to dementia

INTRODUCTION

Diabetes is a well-established risk factor for dementia, but its impact on the prodromal phase of dementia is unclear.

METHODS

Cohorts of older adults who were cognitively healthy (n = 1840) or had cognitive impairment-no dementia (CIND; n = 682) were followed over 12 years to detect incident CIND and dementia, respectively.

RESULTS

Poorly controlled diabetes (glycated hemoglobin [HbA1c] ≥7.5%; reference = normoglycemia) was associated with double the risk of CIND (Cox regression multi-adjusted hazard ratio [HR] 2.01, 95% confidence interval [CI] 1.13-3.58) and triple the risk CIND progressing to dementia (HR 2.87, 95% CI 1.20-6.85). Co-morbid diabetes and heart disease doubled the risk of incident CIND and dementia, although neither disease conferred a significant risk of either outcome alone. Elevated systemic inflammation contributed to the diabetes-associated increased dementia risk.

CONCLUSIONS

Diabetes characterized by poor glycemic control or cardiovascular complications is related to a greater risk of the development and progression of cognitive impairment. Inflammation may play a role in these relationships.

Association between Statins and Retinal Vascular Occlusion: A Population-Based Cohort Study

Retinal vascular occlusion (RVO), including retinal arterial occlusion and retinal vein occlusion, is a common retinal vascular disease that causes visual disturbance. The exact pathogenesis of RVO remains unclear. In all types of RVO patients, hyperlipidemia is more than twofold more common than in controls. Statins have been used to control blood cholesterol levels and have been found to reduce the risk of cardiovascular morbidity and mortality. Moreover, the immunomodulatory functions of statins may play a role in treating inflammatory diseases. This study aimed to evaluate whether patients taking statins have a lower risk of developing RVO compared to patients not taking statins. Adult patients with statins usage on the index date identified from the Taiwan National Health Insurance Research Database (NHIRD) between 2000 and 2013 were included. A threefold matched group was selected using age, sex, and year of index date for comparison. During the mean follow-up period of 12.87 ± 1.88 years, the cumulative incidence of RVO was significantly lower in the statin-user group (29.96 per 105 person-years [PYs]) than in the non-statin-user group (39.35 per 105 PYs). The results showed a lower cumulative incidence rate of RVO in patients prescribed statins than in those not prescribed statins (log-rank test, p = 0.020). The adjusting hazard ratio (HR) was significantly greater for RVO in the statin-user group (adjusted HR, 0.704; 95% CI, 0.591-0.873). Statin users had a decreased risk for all types of RVO development, including central retinal artery occlusion, arterial branch occlusion, central retinal vein occlusion, and branch retinal vein occlusion. In conclusion, patients undergoing statin treatment have a lower risk of developing RVO compared to patients not taking statins.

Antidepressants use is associated with overall survival improvement of patients with gastric cancer after surgery and adjuvant chemotherapy in Taiwan: A large population-based cohort study

To determine whether exposure to antidepressants (ATDs) results in improved overall survival (OS) of patients with gastric cancer (GC) after surgery, we conducted a large cohort study and considered confounding factors that might affect the research outcomes.Patients who received a new diagnosis of GC and received surgery and chemotherapy between 1999 and 2008 were recruited and were classified into different groups based on the ATD level used. The association between the OS of patients with GC after surgery with different levels of ATD use, and the hazard ratio with comorbidities at different ATD use levels were compared.According to Kaplan-Meier method, the more of an ATD was taken, the longer the OS and a dose-dependent relationship was discovered in the OS curve; the adjusted HRs were 0.76 (95% confidence interval [CI] = 0.68-0.84) and 0.48 (95% CI = 0.41-0.57) for ATD users taking a cumulative defined daily dose (cDDD) of 28-167 and ≧168, respectively. Sensitivity analyzes were performed to investigate the effect of various comorbidities on OS with different degrees of ATD use and the results remained consistent among the varying models. Additionally, the effect of ATD use still exhibited a dose-dependent relationship in distinct stratifications for sex and age.The OS for patients with GC after surgery and chemotherapy improved with ATD use, and a dose-dependent relationship was discovered in this study. Further studies on the association between OS of GC and ATD use are required.

Association of Body Mass Index With All-Cause Mortality in Acutely Hospitalized Older Patients

OBJECTIVES

The aim was to examine the relationship between body mass index (BMI) and mortality in older hospitalized patients taking activities of daily living (ADLs) into account.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

Nationwide population-based study of all patients aged ≥65 years admitted to Danish geriatric medical departments during 2005 to 2014 and included in the National Danish Geriatric Database.

METHODS

Patients were followed until death, emigration, or study termination (December 31, 2015). Primary outcome was all-cause mortality. BMI and ADLs were routinely assessed on admission and linked at an individual level to the Danish national health registers. Kaplan-Meier analysis was used to estimate crude survival according to each BMI subcategory and Cox regression to examine the association with mortality adjusting for age, comorbidity, polypharmacy, ADLs, marital status, prior hospitalizations, and admission year.

RESULTS

In total, 74,589 patients (63% women) were included aged [mean (SD)] 82.5 (7.5) years with BMI [mean (SD)] of 23.9 (5.1) kg/m². During follow-up 51,188 died. Follow-up time was 191,972 person-years. Unadjusted and adjusted hazard ratio (HR) for overall, 30-day, and 1-year mortality decreased significantly with increasing BMI. In women, the highest adjusted HR (95% confidence interval) for overall mortality was seen for underweight patients (BMI <16) 1.83 (1.72-1.95) and the lowest for obesity grade II patients (BMI = 35.0-39.9) 0.66 (0.60-0.73) when using normal weight (BMI = 18.5-24.9) as reference. In men, the HR for BMI <16 and BMI = 35.0-39.9 were 1.98 (1.76-2.23) and 0.56 (0.49-0.65), respectively.

CONCLUSIONS AND IMPLICATIONS

In hospitalized older patients, association between mortality and BMI did not show a U-shaped or J-shaped curve after adjustment of multiple confounders, including ADLs. Instead, mortality was highest in patients with low BMI and decreased with increasing BMI before leveling off in the obese range. Our study highlights the need for a debate and reassessment of what should be the ideal BMI in this vulnerable patient group.

Increased risk of diabetes in cancer survivors: a pooled analysis of 13 population-based cohort studies

BACKGROUND

Diabetes is considered as an established risk factor for cancer development. However, the link between diabetes among cancer survivors remains inconclusive. The hypothesis of this study was to assess the hazard ratio (HR) of incidence of diabetes in cancer survivors compared with the HR in the general population.

PATIENTS AND METHODS

A comprehensive literature search was performed in PubMed, Embase, and the Cochrane Library from database inception to 15 December 2020 for population-based cohort studies. Summary effect estimates were combined using random-effects models. We also performed subgroup analyses to test sources of heterogeneity and the stability of the results stratified by various study and participant characteristics.

RESULTS

Thirteen population-based cohort studies involving 1 686 595 participants were analyzed. The HR for the development of diabetes in cancer survivors was 1.39 [95% confidence interval (CI) 1.29-1.50; I2 = 82.3%; P < 0.001] compared with that in noncancer controls, among which survivors of hematological, gynecologic, breast, colorectal and urinary tract cancer (all P < 0.05) showed consistent significant results, whereas no significant increased risk was observed for other cancer types. The effects were more prominent in populations of shorter cancer survival duration (<1 year) (HR 2.09, 95% CI 1.32-3.32; P = 0.009). Moreover, cancer survivors with a longer follow-up period (>10 years) had a relatively higher risk of diabetes (HR 1.54, 95% CI 1.34-1.77) than those with a shorter follow-up period.

CONCLUSIONS

In this large pooled analysis of population-based cohorts, evidence supports the hypothesis that the risk of developing diabetes is increased in cancer survivors compared with the general population. We should interpret the results with caution for considerable interstudy heterogeneity. However, health policy makers should take this as a challenge for the early prevention and effective intervention of diabetes.

Familial Risk of Hashimoto's Thyroiditis Among First-Degree Relatives: A Population-Based Study in Korea

Background: Few small-scale studies have reported a genetic and familial predisposition in Hashimoto's thyroiditis (HT), however, quantified familial risk estimates from population-level data are unavailable. We aimed to estimate the incidence and familial risk of HT among first-degree relatives (FDR) according to age, sex, and family relationships. Methods: We conducted a population-based study in the general population of Korea from 2002 to 2017. Using the nationwide health insurance database, which has full population coverage and family relationship information, a cohort of 22 million individuals with blood-related FDR comprising 12 million families were followed up for a familial occurrence of HT. Age- and sex-adjusted incidence risk ratios (IRRs) were calculated in individuals with an affected FDR compared with those without an affected FDR. Results: Among 21,940,795 individuals, 234,912 had an HT-affected FDR, of whom 2425 familial cases developed HT with an incidence of 7.12/10,000 person-years. The familial risk for HT was 6.5-fold (95% confidence interval [CI]: 6.24-6.78) higher in individuals with versus without affected FDR. According to relationship, familial risks were IRR 102.71, IRR 7.80, IRR 5.54, and IRR 5.52 with an affected twin, sibling, mother, and father, respectively, and the corresponding incidence (/10,000 person-years) was 115.57, 10.66, 5.73, and 5.91. Same-sex twins had three times higher risk of developing HT than opposite-sex twins (IRR 121.01 vs. 21.46). The sex-specific familial risk was higher in males than females. The risks demonstrated age dependence, being higher in younger age groups. Conclusions: This study represents the largest population-based study of familial HT risk in Asia. We demonstrated elevated familial risk of incident HT among FDR, but with lower magnitude as those observed in previous studies. Familial risk increased with the degree of genetic relatedness among FDR indicating a prominent role of genetic factors in the familial aggregation of HT. Elevated risks in the younger age groups should motivate clinicians to screen people with a family history, especially those <30 years.

Can the Risk of Severe Depression-Related Outcomes Be Reduced by Tailoring the Antidepressant Therapy to Patient Characteristics?

Selective serotonin reuptake inhibitors (SSRIs) are the first-line treatment for patients with unipolar depression, yet there is little guidance on which SSRI provides the most benefit to a patient, based on personal characteristics. In this work, we explore whether an individualized treatment strategy can be used by health-care providers to adapt their prescription pattern to reduce the risk of a severe depression-related outcome (SDO) when choosing between citalopram and fluoxetine, 2 commonly prescribed SSRIs. Our population-based cohort study used data from the Clinical Practice Research Datalink, the Hospital Episode Statistics repository, and the Office for National Statistics database in the United Kingdom to create a cohort of individuals diagnosed with depression who were prescribed citalopram or fluoxetine between April 1998 and December 2017. Patients were followed from treatment initiation until occurrence of the SDO outcome, treatment discontinuation, or end of study. To find an optimal treatment strategy, we used dynamic weighted survival modeling, considering patient features such as age, sex, body mass index, previous psychiatric diagnoses, and medications. Our findings suggest that using patient characteristics to tailor the antidepressant drug therapy is associated with an increase of 4 days in the median time to SDO (95% confidence interval: 2, 10 days).

The long-term genetic stability and individual specificity of the human gut microbiome

By following up the gut microbiome, 51 human phenotypes and plasma levels of 1,183 metabolites in 338 individuals after 4 years, we characterize microbial stability and variation in relation to host physiology. Using these individual-specific and temporally stable microbial profiles, including bacterial SNPs and structural variations, we develop a microbial fingerprinting method that shows up to 85% accuracy in classifying metagenomic samples taken 4 years apart. Application of our fingerprinting method to the independent HMP cohort results in 95% accuracy for samples taken 1 year apart. We further observe temporal changes in the abundance of multiple bacterial species, metabolic pathways, and structural variation, as well as strain replacement. We report 190 longitudinal microbial associations with host phenotypes and 519 associations with plasma metabolites. These associations are enriched for cardiometabolic traits, vitamin B, and uremic toxins. Finally, mediation analysis suggests that the gut microbiome may influence cardiometabolic health through its metabolites.

Prevalence and Risk Factors of Infection in the Representative COVID-19 Cohort Munich

Given the large number of mild or asymptomatic SARS-CoV-2 cases, only population-based studies can provide reliable estimates of the magnitude of the pandemic. We therefore aimed to assess the sero-prevalence of SARS-CoV-2 in the Munich general population after the first wave of the pandemic. For this purpose, we drew a representative sample of 2994 private households and invited household members 14 years and older to complete questionnaires and to provide blood samples. SARS-CoV-2 seropositivity was defined as Roche N pan-Ig ≥ 0.4218. We adjusted the prevalence for the sampling design, sensitivity, and specificity. We investigated risk factors for SARS-CoV-2 seropositivity and geospatial transmission patterns by generalized linear mixed models and permutation tests. Seropositivity for SARS-CoV-2-specific antibodies was 1.82% (95% confidence interval (CI) 1.28-2.37%) as compared to 0.46% PCR-positive cases officially registered in Munich. Loss of the sense of smell or taste was associated with seropositivity (odds ratio (OR) 47.4; 95% CI 7.2-307.0) and infections clustered within households. By this first population-based study on SARS-CoV-2 prevalence in a large German municipality not affected by a superspreading event, we could show that at least one in four cases in private households was reported and known to the health authorities. These results will help authorities to estimate the true burden of disease in the population and to take evidence-based decisions on public health measures.

Treatment Outcomes of 9,994 Patients With Extensive-Disease Small-Cell Lung Cancer From a Retrospective Nationwide Population-Based Cohort in the Korean HIRA Database

To investigate the efficacy of irinotecan-based (IP) and etoposide-based (EP) platinum combinations, and of single-agent chemotherapy, for treatment of extensive-disease small cell lung cancer (ED-SCLC), we performed a large-scale, retrospective, nationwide, cohort study. The population data were extracted from the Health Insurance Review and Assessment Service of Korea database from January 1, 2008, to November 30, 2016. A total of 9,994 patients were allocated to ED-SCLC and analyzed in this study. The primary objectives were to evaluate the survival outcomes of systemic first-line treatments for ED-SCLC. For first-line treatment, patients who received IP showed a better time to first subsequent therapy (TFST) of 8.9 months (95% confidence interval [CI], 8.50–9.40) than those who received EP, who had a TFST of 6.8 months (95% CI, 6.77–6.97, P < 0.0001). In terms of overall survival (OS), IP was superior to EP (median OS, 10.8 months; 95% CI, 10.13–11.33 vs. 9.5 months; 95% CI, 9.33–9.73; P < 0.0001). Taken together, in the Korean population, first-line IP combination chemotherapy had significantly favorable effects on OS and TFST.

Can health behaviours prolong survival and compress the period of survival with the disability? A population-based cohort study

BACKGROUND

It remains unclear whether and to what extent health behaviours may prolong survival and compress the period of survival with disability.

OBJECTIVE

To identify modifiable health behaviours that are associated with later disability onset and longer disability-free survival.

DESIGN

This population-based cohort study used data from the Swedish National Study on Ageing and Care in Kungsholmen (SNAC-K) ranging between 2001 and 2016.

SETTING AND SUBJECTS

A total of 3,041 disability-free adults aged ≥60 years were followed up to 15 years.

METHODS

Data on health behaviours were collected at baseline. Information on limitations in activities of daily living was obtained at baseline and during the follow-up. Laplace regression was used to model the median age at death and disability occurrence as a function of health behaviours.

RESULTS

Never smoking, moderate alcohol drinking, rich social network and high leisure activity were individually related to longer survival by 1-3 years. Participants with high leisure activity lived 1.6 years (95% CI: 0.9-2.3) more without a disability. After combining lifestyle factors, social network, and leisure activities into a 4-level 'health behaviour profile', people with the healthiest behaviour profile lived 2.8 years (95% CI: 1.3-4.2) longer, had disability 3.5 years (95% CI: 1.7-5.3) later and lived 0.7 years (95% CI, 0.4-1.1) more without a disability compared to those with the least healthy behaviours profile.

CONCLUSIONS

These findings suggest that health behaviours could prolong the lifespan, and leisure activities may further compress years lived with disability among older adults.

Ninth-grade school achievement in Danish children conceived following fertility treatment: a population-based cohort study

OBJECTIVE

To assess whether academic achievement among children conceived following fertility treatment is different from that of children born to fertile women while also considering the underlying infertility.

DESIGN

Population-based cohort study.

SETTING

Denmark.

PATIENT(S)

The study population consisted of all 154,536 firstborn, live-born, singleton children in Denmark between 1995 and 2000 who completed their ninth grade with an examination.

INTERVENTION(S)

The Danish Infertility Cohort was used to identify children conceived after fertility treatment (n = 10,099), and information on mean school marks was obtained from Statistics Denmark.

MAIN OUTCOME MEASURE(S)

Linear regression models were used to estimate mean differences (MDs) and 95% confidence intervals (CIs). Multiple logistic regression models were used to estimate odds ratios (OR) and 95% CI of not passing the ninth-grade examination.

RESULTS

The crude overall mean marks for children conceived after the various fertility treatment procedures were in general higher than in children born to fertile women. However, after adjustment for potential confounders, the overall mean marks were statistically significantly lower for children conceived after the various fertility treatment procedures (e.g., any fertility treatment: MD -0.13; 95% CI -0.18, -0.08) compared with children born to fertile women. Further, children conceived after any fertility treatment had a statistically significant lower crude likelihood of not passing the ninth-grade examination (OR 0.66; 95% CI 0.53, 0.81) compared with children born to fertile women, whereas no difference was observed in the confounder adjusted analyses (OR 1.15; 95% CI 0.89, 1.49). When children born to women requiring fertility assistance but without fertility treatment in the index pregnancy were used as a reference group, no differences in the adjusted overall mean marks and the likelihood of not passing the ninth grade with an examination were observed.

CONCLUSION

Our findings indicate that fertility treatment per se is not associated with lower school marks and the likelihood of not passing the ninth grade with an examination. Hence, we suggest that factors related to both fertility problems and cognitive development may more likely explain the slightly lower academic performance (i.e., modest lower mean marks) among children conceived after fertility treatment.

The Liability Threshold Model for Predicting the Risk of Cardiovascular Disease in Patients with Type 2 Diabetes: A Multi-Cohort Study of Korean Adults

Personalized risk prediction for diabetic cardiovascular disease (DCVD) is at the core of precision medicine in type 2 diabetes (T2D). We first identified three marker sets consisting of 15, 47, and 231 tagging single nucleotide polymorphisms (tSNPs) associated with DCVD using a linear mixed model in 2378 T2D patients obtained from four population-based Korean cohorts. Using the genetic variants with even modest effects on phenotypic variance, we observed improved risk stratification accuracy beyond traditional risk factors (AUC, 0.63 to 0.97). With a cutoff point of 0.21, the discrete genetic liability threshold model consisting of 231 SNPs (GLT₂₃₁) correctly classified 87.7% of 2378 T2D patients as high or low risk of DCVD. For the same set of SNP markers, the GLT and polygenic risk score (PRS) models showed similar predictive performance, and we observed consistency between the GLT and PRS models in that the model based on a larger number of SNP markers showed much-improved predictability. In silico gene expression analysis, additional information was provided on the functional role of the genes identified in this study. In particular, HDAC4, CDKN2B, CELSR2, and MRAS appear to be major hubs in the functional gene network for DCVD. The proposed risk prediction approach based on the liability threshold model may help identify T2D patients at high CVD risk in East Asian populations with further external validations.

Risk of Total Knee and Hip Arthroplasty in Patients With Rheumatoid Arthritis: A 12-Year Retrospective Cohort Study of 65,898 Patients

BACKGROUND

Rheumatoid arthritis (RA) is an inflammatory disease that causes the destruction of soft tissues and cartilage around joints. Owing to the widespread use of potent disease-modifying antirheumatic drugs, the need for total knee and hip arthroplasties (TKA and THA) has been reduced in patients with RA. However, the current association between RA and either THA or TKA has not been demonstrated in large-scale epidemiological studies.

METHODS

We conducted a large-scale retrospective cohort study of patients diagnosed with RA during a 12-year period (2000-2012) in Taiwan. We recruited 32,949 patients with RA and 32,949 individually propensity score-matched non-RA controls.

RESULTS

After adjusting for confounding factors, we found that the risk of THA or TKA was 4.02 times higher in patients with RA than in those without RA (95% confidence interval [CI], 3.77-4.52). The risk of THA or TKA was highest in patients with RA younger than 40 years (adjusted hazard ratio, 43.18; 95% CI, 16.01-116.47). Compared with non-RA patients, patients with RA were 4.82 times more likely to undergo THA (95% CI, 3.84-6.04), 3.85 times more likely to undergo TKA (95% CI, 3.48-4.25), and 19.06 times more likely to undergo both THA and TKA (95% CI, 8.90-40.80).

CONCLUSION

These findings document a 4.02-fold greater long-term risk of undergoing THA or TKA in RA patients relative to non-RA patients in Taiwan.

The association between Candida infection and ankylosing spondylitis: a population-based matched cohort study

AIMS

To explore whether newly diagnosed Candida infection increases the risk of developing ankylosing spondylitis (AS).

METHODS AND MATERIALS

We investigated 61,550 patients with newly diagnosed Candida infection between 1997 and 2013 from the Taiwan National Health Insurance Research Datasets to conduct a population-based matched-cohort study. Controls were 61,550 subjects without Candida infection and propensity score matched with the Candida exposure cohort. The follow-up period was defined as month from the initial diagnosis of Candida infection (or nested index date for controls) to the date of AS, or 31 December 2013. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the occurrence of AS.

RESULTS

The incidence rates of AS in the Candida group and comparison group were respectively 4.58 and 3.88 per 100,000 person-months. The adjusted HR (95% CI) of AS for the Candida group was 1.19 (0.99-1.44) compared to the control group after adjustment for age, gender and all covariates (95% CI = 1.77-2.27). However, an adjusted hazard ratio (aHR) of 1.77-fold (95% CI = 1.26-2.53) significant increase in the risk of developing AS was observed after 6 years of follow-up, when exposure to Candida was at baseline. The effect of Candida infection was significantly time varying (p value for interaction between follow-up period and Candida infection is .018).

CONCLUSIONS

A risk of AS was found after Candida infection, and a year of follow-up acts as an effect modifier between the Candida infection and risk of AS. Key messages What is already known on this subject? Links between spondyloarthritis and fungal infections have been found in animal studies before. What does this study add? Our study demonstrated that Candida infection is an independent risk factor for developing ankylosing spondylitis in terms of gender, age and relevant variables and comorbidities. A risk of ankylosing spondylitis was found after Candida infection, and year of follow-up acts as an effect modifier between the Candida infection and risk of AS. Clinicians should be aware of possible Candida infection in managing patients with ankylosing spondylitis. Implications: Clinicians must pay greater attention to patients with newly diagnosed Candida infection. Specifically, they should conduct tests for ankylosing spondylitis. Further research is needed to examine if and how treatment of Candida infection alleviates symptoms of AS.

The risk of chronic kidney disease among women with polycystic ovary syndrome: A long-term population-based cohort study

BACKGROUND AND OBJECTIVE

Results of studies focusing on chronic kidney disease (CKD) among women with polycystic ovary syndrome (PCOS) are insufficient and controversial. This study aimed to evaluate the incidence rate of CKD in women with PCOS, compared to a control group of healthy women.

METHODS

This study was a population-based cohort study conducted from among 1460 reproductive-age women including 156 women with PCOS and 1304 controls. Incidence rates per 1000 person-years of follow-up were calculated for PCOS and control groups. Cox proportional hazards regression with age as the time-scale was used to estimate hazard ratios (HR) and 95% confidence intervals for developing CKD in relation to PCOS in both univariable and multivariable models.

RESULTS

During a median follow-up of 12.9 years, 330 new cases of CKD were identified, including 25 PCOS women (14.8 per 1000 person-years; 95% CI, 10-22) and 305 healthy controls (21.5 per 1000 person-years; 95% CI, 19.2-24.1). The results of the Cox model showed that the risk of CKD among women with PCOS and healthy women is comparable and women with PCOS did not have a higher risk of developing CKD compared to healthy women (unadjusted HR: 0.883; 95% CI: 0.587-1.328; P = .551). The results remained unchanged after adjustment for potential confounders of smoking status, BMI, hypertension and diabetes at baseline and follow-up of study (multiple adjusted HR: 0.911; 95% CI: 0.600-1.383; P = .661).

CONCLUSION

Our population-based study with a long-term follow-up period showed that the risk of CKD in PCOS patients was similar to the general female population. Large studies, with long-term follow-up and more diverse phenotypes, are needed to confirm the findings.

Childhood appendectomy and adult mental disorders: A population-based cohort study

BACKGROUND

Recent studies suggest that disruption of the colonic microbiota homeostasis is associated with low-grade systemic inflammation and mental disorders. The cecal appendix may influence the homeostasis of the colonic microbiota. In this large population-based study, we investigated whether early removal of the appendix is associated with an increased risk of mental disorders later in life.

MATERIALS AND METHODS

All Swedish individuals born between 1973 and 1992 (N = 1,937,488) were included and followed prospectively until December 31, 2016 for any psychiatric International Classification of Disease diagnosis from age 14 or later in life. The main exposure was defined as having a history of appendectomy before age 14 (N = 44,259); the second exposure, appendicitis before age 14 but without appendectomy (N = 1,542), and the third exposure studied was a history of hernia surgery before age 14 (N = 35,523). Control groups for each respective exposure were all unexposed individuals in the study population.

RESULTS

Individuals exposed to appendectomy before age 14 had a 19% increased risk of depressive disorder (adjusted hazard ratio [aHR] = 1.19; 95% confidence interval [95% CI]: 1.15-1.23), 27% increased risk of bipolar affective disorder (aHR = 1.27; 95% CI: 1.17-1.37), and a 20% increased risk of an anxiety disorder (aHR = 1.20; 95% CI: 1.16-1.23) compared to individuals unexposed to childhood appendectomy. We found no association between appendectomy and increased risk of obsessive-compulsive disorder and schizophrenia and there was no association between appendicitis without appendectomy and mental disorders. The association between childhood hernia surgery and mental disorders later in life was small but significant.

CONCLUSION

Childhood appendectomy, but not appendicitis without appendectomy, was associated with a significantly increased risk of mood and anxiety disorders in adulthood.

Hypertension Risk in Young Women With Polycystic Ovary Syndrome: A Nationwide Population-Based Cohort Study

Objective: A number of publications have assessed the prevalence of hypertension in polycystic ovary syndrome (PCOS) patients with inconclusive results. Since in general populations the occurrence of hypertension is related to age and comorbidities, we investigated the incidence rate and hazard ratios (HRs) of hypertension between healthy subjects and young women with PCOS as well as comorbidities.

Methods: We conducted a population-based retrospective cohort study by using the National Health Insurance Research Database in Taiwan. The cohort included women with the diagnosis of PCOS between 2000 and 2012. Those without PCOS were selected as the control group at a ratio of 4:1 by an age-matched systematic random-sampling method. Cox proportional hazard regression analysis was used to determine the effects of PCOS on the risks of developing hypertension. Stratification analysis was performed to elucidate the interaction among PCOS and the comorbidities, which affect the incidence of hypertension.

Results: The PCOS cohort consisted of 20,652 patients with PCOS and the comparison cohort consisted of 82,608 matched patients without PCOS. There was no difference in the distribution of age between the PCOS cohort and the comparison cohort (29.1 ± 6.8 vs. 29.0 ± 6.5, p = 0.32). The incidence rates of hypertension were 7.85 and 4.23 per 1,000 person-years in the PCOS and comparison groups, respectively. A statistically significant higher risk of hypertension was found in the PCOS cohort (adjusted HR = 1.62, 95% confidence interval = 1.48–1.76) than in the comparison cohort. After a joint analysis of comorbidities, the adjusted HR of hypertension was 9.44 (95% confidence interval = 7.27–12.24) for PCOS patients with comorbidities of diabetes mellitus (DM) and hyperlipidemia compared with women with neither PCOS nor DM and hyperlipidemia.

Conclusion: The risk of developing hypertension in young women with PCOS was higher than in controls in this cohort study. The comorbidities of DM and hyperlipidemia could interact with PCOS patients and further increase the risk of hypertension. An earlier screening for hypertension and comorbidities in patients with PCOS may be warranted, even in young women.

Association between Anemia and Stroke in Females: A Nationwide, Population-Based Cohort Study in Taiwan

Optimal stroke prevention strategies for women should take into account specific sex-related stroke risk factors. Anemia is a common medical condition in females, particularly in women of reproductive age. This study investigated whether anemia is an independent risk factor for stroke in females in a population-based cohort study. We investigated newly diagnosed anemic female patients with no history of central nervous system disease, psychiatric disorders, traumatic brain injury, major operations or hemorrhagic diseases identified from the Taiwan National Health Insurance Research Database. Non-anemic matched controls (1:1) were selected based on a propensity score estimated using a logistic regression model that included demographic characteristics and comorbidities. A competing risk analysis was applied to estimate the stroke risk in anemic patients compared to that of their matched controls. In our study, the adjusted sub-distribution hazard ratios (aSHRs) of overall, hemorrhagic and ischemic stroke in anemic female patients aged <50 years were 1.35 (95% confidence interval (CI): 1.19-1.52, p < 0.001), 1.31 (95% CI, 1.09-1.56, p < 0.003), and 1.35 (95% CI, 1.15-1.58, p < 0.001), respectively, compared to non-anemic female controls. However, a positive association between anemia and stroke was not found for those aged ≥50 years. Similar results were observed when the follow-up age was limited to 50 years to reduce the potential effects of menopause on stroke. In conclusion, the present population-based cohort study found that anemia is a potential risk factor for overall, hemorrhagic and ischemic stroke in females of reproductive age.