Model-based estimation of the attributable fraction for cross-sectional, case–control and cohort studies using the R package AF

Cardiometabolic factors and population risks of cardiovascular disease in community-dwelling adults with varied blood pressure statuses

AIMS

To examine the differential associations between cardiometabolic risk factors and cardiovascular disease (CVD), and to evaluate the population-attributable fractions (PAFs) for CVD among community-dwelling adults with varied blood pressure (BP) statuses.

METHODS

This prospective cohort study included participants without prevalent CVD from a subcohort of the China Patient-Centred Evaluative Assessment of Cardiac Events Million Persons Project. Participants were divided into four BP groups according to the American College of Cardiology/American Heart Association guidelines. The study exposure comprised the selected cardiometabolic risk factors, including waist circumference (WC), body mass index, (BMI) heart rate, fasting blood glucose (FBG), low-density lipoprotein cholesterol, and remnant cholesterol. The outcome was hospitalizations for CVD. Cox proportional hazard models were conducted, and the PAFs were calculated in the analysis.

RESULTS

Among the 94 183 participants (39.0% were men, mean age: 54.2 years), 26.6% had Stage 1 hypertension and 30.8% had Stage 2 hypertension. A total of 6065 hospitalizations for CVD were captured after a median follow-up of 3.5 years. BP (per 1-standard deviation [SD]: hazard ratio [HR] 1.34, 95% confidence interval [CI] 1.29, 1.40), FBG (per 1-SD: HR 1.16, 95% CI 1.14, 1.19) and WC (per 1-SD: HR 1.41, 95% CI 1.36, 1.47) were three major contributors to CVD events. BP status significantly modified the associations of abdominal obesity, suboptimal BMI, suboptimal heart rate and abnormal FBG with CVD, with stronger associations with CVD observed in optimal BP groups compared to hypertensive groups (p for risk factor-by-BP group interaction <0.05). Participants with all cardiometabolic risk factors were at the highest risk for CVD, accounting for 35.6% (95% CI 30.0, 40.8) of the PAF for CVD. Among the risk factors, BP control explained the highest PAF for CVD (15.1%, 95% CI 8.2, 21.4) The overall PAFs of cardiometabolic risk factors for CVD were higher among the normotensive participants compared to the hypertensive participants.

CONCLUSIONS

The awareness and control rates of hypertension were extremely low among Southern Chinese adults. BP status significantly modified the associations between cardiometabolic risk factors and CVD, and the overall PAFs for CVD were higher among people with normal BP. Dedicated efforts are needed to improve the management of cardiometabolic factors.

Lifestyle factors and their relative contributions to longitudinal progression of cardio-renal-metabolic multimorbidity: a prospective cohort study

BACKGROUND

The role of lifestyle factors and their relative contributions to the development and mortality of cardio-renal-metabolic multimorbidity (CRMM) remains unclear.

METHODS

A study was conducted with 357,554 UK Biobank participants. CRMM was defined as the coexistence of two or three cardio-renal-metabolic diseases (CRMDs), including cardiovascular disease (CVD), type 2 diabetes (T2D) and chronic kidney disease (CKD). The prospective study examined the associations of individual and combined lifestyle scores (diet, alcohol consumption, smoking, physical activity, sedentary behavior, sleep duration and social connection) with longitudinal progression from healthy to first cardio-renal-metabolic disease (FCRMD), then to CRMM, and ultimately to death, using a multistate model. Subsequently, quantile G-computation was employed to assess the relative contribution of each lifestyle factor.

RESULTS

During a median follow-up of 13.62 years, lifestyle played crucial role in all transitions from healthy to FCRMD, then to CRMM, and ultimately to death. The hazard ratios (95% CIs) per score increase were 0.91 (0.90, 0.91) and 0.90 (0.89, 0.91) for healthy to FCRMD, and for FCRMD to CRMM, and 0.84 (0.83, 0.86), 0.87 (0.86, 0.89), and 0.90 (0.88, 0.93) for mortality risk from healthy, FCRMD, and CRMM, respectively. Among the seven factors, smoking status contributed to high proportions for the whole disease progression, accounting for 19.88-38.10%. High-risk diet contributed the largest proportion to the risk of transition from FCRMD to CRMM, with 22.53%. Less-frequent social connection contributed the largest proportion to the risk of transition from FCRMD to death, with 28.81%. When we further consider the disease-specific transitions, we find that lifestyle scores had slightly stronger associations with development to T2D than to CVD or CKD.

CONCLUSIONS

Our study indicates that a healthy lifestyle may have a protective effect throughout the longitudinal progression of CRMM, informing more effective management and treatment. Smoking status, diet, and social connection played pivotal roles in specific disease transitions.

Estimating and displaying population attributable fractions using the R package: graphPAF

Here we introduce graphPAF, a comprehensive R package designed for estimation, inference and display of population attributable fractions (PAF) and impact fractions. In addition to allowing inference for standard population attributable fractions and impact fractions, graphPAF facilitates display of attributable fractions over multiple risk factors using fan-plots and nomograms, calculations of attributable fractions for continuous exposures, inference for attributable fractions appropriate for specific risk factor → mediator → outcome pathways (pathway-specific attributable fractions) and Bayesian network-based calculations and inference for joint, sequential and average population attributable fractions in multi-risk factor scenarios. This article can be used as both a guide to the theory of attributable fraction estimation and a tutorial regarding how to use graphPAF in practical examples.

Association of sleep traits with benign prostatic hyperplasia in middle-aged and elderly men: A prospective analysis in UK Biobank

AIMS

The association of sleep traits (insomnia, sleep duration, chronotype, daytime sleepiness, and snoring) with benign prostatic hyperplasia (BPH) is unclear. This research aimed to examine the effects of sleep traits on BPH risk.

METHODS

A total of 170 241 men aged 38 to 73 years from UK Biobank were included. An overall healthy sleep score was created based on five sleep traits. A Cox regression model was utilized to compute adjusted hazard ratios (HRs) and population attributable fractions (PAFs) with 95% confidence intervals (CIs) for BPH risk in relation to sleep traits.

RESULTS

During a median of 12.0 years follow-up, 13 026 incident BPH cases occurred. We observed that sleep duration (7-8 h/d; HR 0.95; 95% CI 0.92-0.99), no frequent insomnia (HR 0.71; 95% CI 0.69-0.74), and no frequent daytime sleepiness (HR 0.86; 95% CI 0.79-0.93) were significantly related to reduced BPH risk. Each one-point increment of the healthy sleep score was related to a decreased BPH risk, with an adjusted HR of 0.90 (95% CI 0.89-0.92). The multivariable-adjusted HR in men adopting five versus zero to one low-risk sleep traits was 0.68 (95% CI 0.61-0.75) for BPH risk. Estimates of the PAF indicated that 9.1% (95% CI 5.8-12.5%) of BPH cases would be prevented if all individuals had adopted all five low-risk sleep traits, assuming causality.

CONCLUSIONS

Our study indicates an association between a healthy sleep pattern and a lower risk of BPH, emphasizing the importance of adhering to such patterns for potentially reducing BPH risk. Geriatr Gerontol Int 2024; 24: 675-682.

Sex Differences in the Associations of Traditional Risk Factors and Incident Heart Failure Hospitalization: A Prospective Cohort Study of 102 278 Chinese General Adults

BACKGROUND

Evidence regarding sex differences in the associations of traditional risk factors with incident heart failure (HF) hospitalization among Chinese general adults is insufficient. This study aimed to evaluate the potential sex differences in the associations of traditional risk factors with HF among Chinese general adults.

METHODS AND RESULTS

Data were from a subcohort of the China PEACE (Patient-Centered Evaluative Assessment of Cardiac Events) Million Persons Project. The traditional risk factors were collected at baseline, and the study outcome was HF-related hospitalization identified from the Inpatients Registry. A total of 102 278 participants (mean age, 54.3 years; 39.5% men) without prevalent HF were recruited. A total of 1588 cases of HF-related hospitalization were captured after a median follow-up of 3.52 years. The incidence rates were significantly higher in men (2.1%) than in women (1.2%). However, the observed lower risk of HF in women was significantly attenuated or even vanished when several traditional risk factors were poorly controlled (P for sex-by-risk factors <0.05). The selected 11 risk factors collectively explained 62.5% (95% CI, 55.1-68.8) of population attributable fraction for HF in women, which is much higher than in men (population attributable fraction, 39.6% [95% CI, 28.5-48.9]).

CONCLUSIONS

Although women had a lower incidence rate of hospitalization for HF than men in this study, the risk for HF increased more remarkably in women than in men when several traditional risk factors were poorly controlled. This study suggests that intensive preventative strategies are immediately needed in China.

Mediating role of systemic inflammation in the association between heavy metals exposure and periodontitis risk

BACKGROUND

This study evaluated the mediating role of systemic inflammation in the association between exposure to heavy metals and periodontitis in a nationwide sample of adults.

METHODS

Pooled cross-sectional data from the National Health and Nutrition Examination Survey (NHANES 2009-2014) were used (n = 8993). Periodontitis was defined by a full-mouth examination and classified as no/mild and moderate/severe (mod/sev) groups. Blood and urinary heavy metal levels were investigated, including cadmium (Cd), lead (Pb), and mercury (Hg). In addition, systemic inflammation was assessed using circulatory leukocyte counts and C-reactive protein (CRP) levels.

RESULTS

Multivariable logistic regression analysis revealed the positive associations of blood and urinary levels of Cd and Pb with mod/sev periodontitis. In contrast,blood Hg levels did not show a significant association. The odds of having periodontitis were 1.233 and 1.311 times higher for each one-unit increment in Ln-transformed blood Cd (95% confidence interval [CI]: 1.109-1.371) and Pb (95% CI: 1.170-1.470), respectively. Mediation analysis suggested a 6.3% to 11.5% contribution of leucocyte counts in the association of blood Cd and Pb levels with periodontitis. Sensitivity analyses for urinary Cd levels yielded consistent mediating effects. However, no significant mediating effect of CRP was detected.

CONCLUSION

Higher exposures to Cd and Pb were positively associated with periodontitis risk. These associations might be partially mediated by the elevated levels of leukocytes rather than CRP. Further longitudinal studies are needed to elucidate the discordant results of the systemic inflammatory biomarkers.

The causal effect of early retirement on medication use across sex and occupation: evidence from Danish administrative data

We examine the causal effect of early retirement on medication use using Danish registry data. A reform in early retirement schemes in 2006 gradually increased eligibility ages from 60 to 64 differentially across birth cohorts. This enables an instrumental variable design that was applied using novel g-estimation methods that alleviate bias in binary outcome IV models. Our data allow studying patterns in the short run (ages 59½-60½) and in the long run (ages 57-63). For those who were eligible already at age 60, retirement did not change overall medication use. However, when investigating medication and population subgroups, we see that painkiller use decreases and hypertension medication as well as mental health medication use increase after retirement in almost all population subgroups. Moreover, males as well as the blue-collar occupation subgroups do show decreases in overall medication use after early retirement. In conclusion, our analyses reveal that retirement can have important heterogeneous health effects across population groups and are potentially informative about the welfare benefits of social insurance more broadly.

Maternal Exposure to Extreme Cold Events and Risk of Congenital Heart Defects: A Large Multicenter Study in China

Over the past decade, extreme temperature events have become more frequent and longer in duration. Previous studies on the association between extreme cold events (ECEs) and congenital heart defects (CHDs) are few and inconsistent. We conducted a national multicenter study in 1313 hospitals in 26 provinces in China and collected a total of 14 808 high CHD-risk participants from 2013 to 2021. We evaluated the ECEs experienced by each pregnant women during the embryonic period (3-8 weeks). The results indicated that ECEs experienced by pregnant women during the embryonic period were associated with the development of fetal CHD and were more strongly associated with some specific fetal CHD subtypes, such as pulmonary stenosis, pulmonary atresia, and tetralogy of Fallot. Of the CHD burden, 2.21% (95% CI: 1.43, 2.99%)-2.40% (95% CI: 1.26, 3.55%) of fetal CHD cases were attributable to ECEs during the embryonic period. Our findings emphasize the need to pay more attention to pregnant women whose embryonic period falls during the cold season to reduce cold spell detriments to newborns.

Occupational noise and hypertension in Southern Chinese workers: a large occupational population-based study

INTRODUCTION

An increasing number of original studies suggested that occupational noise exposure might be associated with the risk of hypertension, but the results remain inconsistent and inconclusive. In addition, the attributable fraction (AF) of occupational noise exposure has not been well quantified. We aimed to conduct a large-scale occupational population-based study to comprehensively investigate the relationship between occupational noise exposure and blood pressure and different hypertension subtypes and to estimate the AF for hypertension burden attributable to occupational noise exposure.

METHODS

A total of 715,135 workers aged 18-60 years were included in this study based on the Key Occupational Diseases Surveillance Project of Guangdong in 2020. Multiple linear regression was performed to explore the relationships of occupational noise exposure status, the combination of occupational noise exposure and binaural high frequency threshold on average (BHFTA) with systolic and diastolic blood pressure (SBP, DBP). Multivariable logistic regression was used to examine the relationshipassociation between occupational noise exposure status, occupational noise exposure combined with BHFTA and hypertension. Furthermore, the attributable risk (AR) was calculated to estimate the hypertension burden attributed to occupational exposure to noise.

RESULTS

The prevalence of hypertension among occupational noise-exposed participants was 13·7%. SBP and DBP were both significantly associated with the occupational noise exposure status and classification of occupational noise exposure combined with BHFTA in the crude and adjusted models (all P < 0·0001). Compared with workers without occupational noise exposure, the risk of hypertension was 50% greater among those exposed to occupational noise in the adjusted model (95% CI 1·42-1·58). For participants of occupational noise exposed with BHFTA normal, and occupational noise exposed with BHFTA elevated, the corresponding risks of hypertension were 48% (1·41-1·56) and 56% (1·46-1·63) greater than those of occupational noise non-exposed with BHFTA normal, respectively. A similar association was found in isolated systolic hypertension (ISH) and prehypertension. Subgroup analysis by sex and age showed that the positive associations between occupational noise exposure and hypertension remained statistically significant across all subgroups (all P < 0.001). Significant interactions between occupational noise status, classification of occupational noise exposure combined with BHFTA, and age in relation to hypertension risk were identified (all P for interaction < 0.001). The associations of occupational noise status, classification of occupational noise exposure combined with BHFTA and hypertension were most pronounced in the 18-29 age groups. The AR% of occupational noise exposure for hypertension was 28·05% in the final adjusted model.

CONCLUSIONS

Occupational noise exposure was positively associated with blood pressure levels and the prevalence of hypertension, ISH, and prehypertension in a large occupational population-based study. A significantly increased risk of hypertension was found even in individuals with normal BHFTA exposed to occupational noise, with a further elevated risk observed in those with elevated BHFTA. Our findings provide epidemiological evidence for key groups associated with occupational noise exposure and hypertension, and more than one-fourth of hypertension cases would have been prevented by avoiding occupational noise exposure.

Multimorbidity and mortality among older patients with coronary heart disease in Shenzhen, China

BACKGROUND

The current understanding of the magnitude and consequences of multimorbidity in Chinese older adults with coronary heart disease (CHD) is insufficient. We aimed to assess the association and population-attributable fractions (PAFs) between multimorbidity and mortality among hospitalized older patients who were diagnosed with CHD in Shenzhen, China.

METHODS

We conducted a retrospective cohort study of older Chinese patients (aged ≥ 65 years) who were diagnosed with CHD. Cox proportional hazards models were used to estimate the associations between multimorbidity and all-cause and cardiovascular disease (CVD) mortality. We also calculated the PAFs.

RESULTS

The study comprised 76,455 older hospitalized patients who were diagnosed with CHD between January 1, 2016, and August 31, 2022. Among them, 70,217 (91.9%) had multimorbidity, defined as the presence of at least one of the predefined 14 chronic conditions. Those with cancer, hemorrhagic stroke and chronic liver disease had the worst overall death risk, with adjusted HRs (95% CIs) of 4.05 (3.77, 4.38), 2.22 (1.94, 2.53), and 1.85 (1.63, 2.11), respectively. For CVD mortality, the highest risk was observed for hemorrhagic stroke, ischemic stroke, and chronic kidney disease; the corresponding adjusted HRs (95% CIs) were 3.24 (2.77, 3.79), 1.91 (1.79, 2.04), and 1.81 (1.64, 1.99), respectively. All-cause mortality was mostly attributable to cancer, heart failure and ischemic stroke, with PAFs of 11.8, 10.2, and 9.1, respectively. As for CVD mortality, the leading PAFs were heart failure, ischemic stroke and diabetes; the corresponding PAFs were 18.0, 15.7, and 6.1, respectively.

CONCLUSIONS

Multimorbidity was common and had a significant impact on mortality among older patients with CHD in Shenzhen, China. Cancer, heart failure, ischemic stroke and diabetes are the primary contributors to PAFs. Therefore, prioritizing improved treatment and management of these comorbidities is essential for the survival prognosis of CHD patients from a holistic public health perspective.

Incident cancers attributable to using opium and smoking cigarettes in the Golestan cohort study

Background

Opium consumption has recently been identified as a carcinogen, but the impact of opium use on cancer burden is unknown. We aimed to evaluate the fraction of cancers that could be attributed to opium use alone and in combination with cigarette smoking in a region where opium is widely used.

Methods

50,045 Iranian adults were recruited to this prospective cohort study between 2004 and 2008 and were followed through January 2022. We assessed the association between using opium and/or cigarette smoking and various cancers using proportional hazards regression models. We then calculated population attributable fractions (PAFs) for all cancers and for groups of cancers causally linked to opium and cigarette smoking.

Findings

Of the total participants, 8% only used opium, 8.3% only smoked cigarettes, and 9% used both substances. During a median 14 years of follow-up, 2195 individuals were diagnosed with cancer, including 215 opium-related cancers (lung, larynx, and bladder) and 1609 tobacco-related cancers (20 types). Opium use alone was estimated to cause 35% (95% CI: 26%-45%) of opium-related cancers, while smoking cigarettes alone was estimated to cause 9% (6%-12%) of tobacco-related cancers in this population. Using opium and/or cigarettes was estimated to cause 13% (9%-16%) of all cancers, 58% (49%-66%) of opium-related cancers, and 15% (11%-18%) of tobacco-related cancers. Moreover, joint exposure to opium and cigarettes had the greatest impact on cancers of the larynx, pharynx, lung, and bladder, with PAFs ranging from 50% to 77%.

Interpretation

Using opium and smoking cigarettes account for a large proportion of cancers in this population. To reduce the cancer burden, prevention policies should aim to decrease the use of both substances through public awareness campaigns and interventional efforts.

Funding

The Golestan Cohort Study work was funded by the Tehran University of Medical Sciences, Cancer Research UK, U.S. National Cancer Institute, International Agency for Research on Cancer. The presented analysis was supported by the International HundredK+ Cohorts Consortium (IHCC).

Association of a Healthy Lifestyle, Life's Essential 8 Scores With Incident Macrovascular and Microvascular Disease Among Individuals With Type 2 Diabetes

Background The association of a healthy lifestyle with the prognosis of type 2 diabetes remains uncertain. We aimed to evaluate the associations of a healthy lifestyle and a higher American Heart Association's Life's Essential 8 score with incident macrovascular and microvascular diseases in type 2 diabetes. Methods and Results A total of 13 543 participants with baseline type 2 diabetes and free of macrovascular and microvascular diseases from the UK Biobank were included. A healthy lifestyle was determined based on body mass index, smoking, alcohol consumption, physical activity, sleep duration, and diet. Life's Essential 8 scores were generated from 8 metrics according to the American Heart Association's cardiovascular health advisory, ranging from 0 to 100. During a median follow-up of 12.1 years, 3279 (24.2%) incident macrovascular diseases and 2557 (18.9%) microvascular diseases were documented. Compared with those with a poor lifestyle, participants with an ideal lifestyle had significantly lower risks of incident macrovascular disease (hazard ratio [HR], 0.46 [95% CI, 0.36-0.59]) and microvascular disease (HR, 0.60 [95% CI, 0.47-0.77]). Significantly lower risks of macrovascular disease (HR, 0.20 [95% CI, 0.05-0.79]) and microvascular disease (HR, 0.24 [95% CI, 0.06-0.98]) were also found in the high cardiovascular health group (Life's Essential 8 scores: 80-100), compared to the low cardiovascular health group (scores: 0-49). Adhering to an ideal lifestyle may prevent 37.0% of macrovascular disease and 24.7% of microvascular disease, and attaining a high cardiovascular health may prevent 71.9% of macrovascular disease and 67.5% of microvascular disease. Conclusions A healthy lifestyle and a higher Life's Essential 8 score were associated with lower risks of macrovascular and microvascular diseases among participants with type 2 diabetes.

Sex-specific population attributable risk factors for cardiovascular and all-cause mortality in the general population: Findings from the China PEACE million persons project

Little evidence exists regarding the sex-specific population attributable risk factors for cardiovascular and all-cause mortality in the Chinese general population. We used a sub-cohort of the China Patient-Centered Evaluative Assessment of Cardiac Events million persons project to evaluate the overall and sex-specific associations and population attributable fractions (PAFs) of twelve risk factors for cardiovascular and all-cause mortality. 95,469 participants were included between January 2016 and December 2020. The twelve risk factors (including four socioeconomic status and eight modifiable risk factors) were collected or measured at baseline. The outcomes of the study were all-cause mortality and cardiovascular mortality. Overall, 60.7% (N = 57,971) were women, and the mean age was 54.3 ± 10.2 years. After a median of 3.52 years of follow-up, 1311 (1.4%) people died, and 362 (0.4%) people died of cardiovascular causes. Majorities of risk factors were significantly associated with all-cause and cardiovascular mortality, and suboptimal blood pressure and low educational attainment were the two leading attributable risk factors for all-cause and cardiovascular mortality. The twelve risk factors collectively explained 72.4% (95% confidence interval (CI): 63.5, 79.2) and 84.0% (95% CI: 71.1, 91.1) of PAFs for all-cause and cardiovascular mortality. When stratified by sex, men had more risk factors that were significantly attributable to mortality than women, whereas low educational attainment had a more pronounced impact on female cardiovascular health. This study found that the twelve risk factors collectively explained a significant proportion of PAFs for all-cause and cardiovascular mortality. Several sex-related disparities in the associations between risk factors and mortality were noted.

Polygenic risk scores and risk stratification in deep vein thrombosis

INTRODUCTION

Deep vein thrombosis (DVT) is a complex disease, where 60 % of risk is due to genetic factors, such as the Factor V Leiden (FVL) variant. DVT is either asymptomatic or manifests with unspecific symptoms and, if left untreated, DVT leads to severe complications. The impact is dramatic and currently, there is still a research gap in DVT prevention. We characterized the genetic contribution and stratified individuals based on genetic makeup to evaluate if it favorably impacts risk prediction.

METHODS

In the UK Biobank (UKB), we performed gene-based association tests using exome sequencing data, as well as a genome-wide association study. We also constructed polygenic risk scores (PRS) in a subset of the cohort (Number of cases = 8231; Number of controls = 276,360) and calculated the impact on the prediction capacity of the PRS in a non-overlapping part of the cohort (Number of cases = 4342; Number of controls = 142,822). We generated additional PRSs that excluded the known causative variants.

RESULTS

We discovered and replicated a novel common variant (rs11604583) near the region where are located the TRIM51 and LRRC55 genes and identified a novel rare variant (rs187725533) located near the CREB3L1 gene, associated with 2.5-fold higher risk of DVT. In one of the PRS models constructed, the top decile of risk is associated with 3.4-fold increased risk, an effect that is 2.3-fold when excluding FVL carriers. In the top PRS decile, the cumulative risk of DVT at the age of 80 years is 10 % for FVL carriers, contraposed to 5 % for non-carriers. The population attributable fractions of having a high polygenic risk on the rate of DVT was estimated to be around 20 % in our cohort.

CONCLUSION

Individuals with a high polygenic risk of DVT, and not only carriers of well-studied variants such as FVL, may benefit from prevention strategies.

A healthy lifestyle, Life's Essential 8 scores and new-onset severe NAFLD: A prospective analysis in UK Biobank

BACKGROUND

The association of a healthy lifestyle and the American Heart Association (AHA) Life's Essential 8 (LE8) score with the risk of new-onset nonalcoholic fatty liver disease (NAFLD) remains uncertain. We aimed to explore the associations between a healthy lifestyle and higher LE8 scores with new-onset severe NAFLD in the general population.

METHODS

266,645 participants without prior liver diseases were included from the UK Biobank. A healthy lifestyle was determined based on body mass index, smoking, alcohol consumption, physical activity, sleep duration, and diet. LE8 score was generated from 8 metrics according to the AHA cardiovascular health (CVH) advisory, varying from 0 to 100 scores. The primary study outcome was new-onset severe NAFLD. The study outcomes were ascertained by hospital inpatient data, cancer registry, and death register records.

RESULTS

During a median follow-up of 11.9 years, 2284(0.9 %) participants developed severe NAFLD. Compared with those with a poor lifestyle, participants with intermediate (HR, 0.60; 95%CI: 0.55-0.67), or ideal (HR, 0.20; 95%CI: 0.15-0.27) lifestyles had a significantly lower risk of new-onset severe NAFLD. Compared to the low CVH group (LE8 scores: 0-49), the moderate (scores:50-79) (HR, 0.43; 95%CI: 0.39-0.48) and high CVH (scores:80-100) (HR, 0.10; 95%CI: 0.07-0.14) group had a significantly lower risk of new-onset severe NAFLD. Accordingly, adhering to a healthy lifestyle and attaining a high CVH in all individuals could prevent 66.8 % (95%CI: 58.5-75.1 %) and 77.3 % (95%CI:70.4-84.2 %) of severe NAFLD, respectively. Genetic risks of NAFLD did not modify these associations.

CONCLUSION

A favorable lifestyle and a higher LE8 score were significantly associated with a lower risk of new-onset severe NAFLD, independent of genetic risks of NAFLD.

Population fraction of Parkinson's disease attributable to preventable risk factors

Parkinson's disease is the fastest growing neurologic disease with seemingly no means for prevention. Intrinsic risk factors (age, sex, genetics) are inescapable, but environmental factors are not. We studied population attributable fraction and estimated fraction of PD that could be reduced if modifiable risk factors were eliminated. Assessing several known risk factors simultaneously in one study, we demonstrate that all were operative and independent, underscoring etiological heterogeneity within a single population. We investigated repeated blows to head in sports or combat as a potential new risk factor, and found it was associated with two-fold increased risk of PD. Considering modifiable risk factors, 23% of PD cases in females were attributable to pesticides/herbicides exposure, and 30% of PD cases in males was attributable to pesticides/herbicides, Agent Orange/chemical warfare, and repeated blows to the head. Thus, one-in-three cases of PD in males, and one-in-four cases in females could have potentially been prevented.

Associations of obesity-related indices with prediabetes regression to normoglycemia among Chinese middle-aged and older adults: a prospective study

Background

Prediabetes is associated with increased cardiovascular risk and all-cause mortality, while its regression will decrease the risks. This study investigated the associations of six obesity-related indices (waist-to-height ratio (WHtR), body roundness index (BRI), conicity index (CI), body shape index (ABSI), Chinese visceral adiposity index (CVAI), and triglyceride glucose (TyG) index) with prediabetes regression based on the China Health and Retirement Longitudinal Study (CHARLS), enrolling middle-aged and older adults.

Methods

We included 2,601 participants with prediabetes from CHARLS, who were followed up from 2011-2012 to 2015-2016, with blood samples collected for measuring fasting plasma glucose and hemoglobin A1c. All the obesity-related indices at baseline and their dynamic changes were calculated and categorized into tertiles. Logistic regression analysis was applied to obtain the odds ratio (OR) and 95% confidence intervals (CIs). Attributable fractions (AFs) and 95% CIs of these indices and the dynamic changes were calculated with the AF package in R software, and the cutoff values of initial obesity-related indices were obtained by the receiver operating characteristic (ROC) analysis.

Results

During the 4-year follow-up period, 562 (21.61%) participants regressed from prediabetes to normoglycemia. They had lower initial BRI, WHtR, CI, ABSI, CVAI, and TyG than those who did not (P < 0.05). After multivariable adjustment, participants in the first tertile of initial BRI (OR, 1.45, 95%CIs, 1.09-1.93), WHtR (OR, 1.46, 95%CIs, 1.10-1.95), and CVAI (OR, 1.47, 95%CIs, 1.11-1.93) had increased odds of prediabetes regression compared with those in the highest tertile. Participants with decreased TyG (OR, 2.08; 95%CIs, 1.61-2.70) also had increased odds of prediabetes regression compared with those with increased TyG. The cutoff values of initial obesity-related indices were 4.374 for BRI, 0.568 for WHtR, 8.621 for TyG, 1.320 for CI, 0.083 for ABSI, and 106.152 for CVAI, respectively. The AFs were 21.10% for BRI < 4.374, 20.85% for WHtR < 0.568, 17.48% for CVAI < 107.794, and 17.55% for ΔTyG < 0, respectively.

Conclusion

Low initial BRI, WHtR, and CVAI, as well as TyG reduction, were significantly related to prediabetes regression to normoglycemia, and the AFs were around 20%. Less abdominal fat and insulin resistance reduction would benefit future health outcomes among people with prediabetes.

Interethnic Differences in Bladder Cancer Incidence and the Association between Type 2 Diabetes and Bladder Cancer in the Multiethnic Cohort Study

Background

Research on the association between type 2 diabetes (T2D) and bladder cancer (BCA) risk among non-European ancestry populations is sparse to nonexistent, and most prior studies rely on a single baseline assessment of T2D status.

Methods

We estimated the T2D-BCA association using the Multiethnic Cohort Study of 185,059 men and women in California and Hawaii. Participants were African American, European American, Japanese American, Latin American, and Native Hawaiian, ages 45-75 years at enrollment (1993-1996). T2D was assessed by self-report at baseline, follow-up surveys, and Medicare claims. Cases were identified using Surveillance, Epidemiology and End Results Program cancer registries through 2016. Associations were estimated by race/ethnicity using Cox proportional hazards regression. Adjusted attributable fractions (AAF) and cumulative absolute risk of bladder cancer were estimated across groups.

Results

Over an average 19.7 years of follow-up 1,890 incident bladder cancer cases were diagnosed. Time-varying T2D was associated with bladder cancer in the multiethnic sample (HR = 1.17; 95% confidence interval, 1.05-1.30); however, the HR did not differ by race/ethnicity (P = 0.85). The AAF was 4.2% in the multiethnic sample and largest among Native Hawaiians (9.8%). Absolute risk of bladder cancer among European Americans without T2D was higher than all other groups with T2D.

Conclusion

T2D is significantly associated with bladder cancer risk in a multiethnic sample.

Significance

Those with T2D have higher incidence of bladder cancer, regardless of racial/ethnic group. Reducing T2D prevalence could substantially lower bladder cancer incidence among Native Hawaiians due to T2D being more common in this group. High absolute risk of bladder cancer among European Americans, regardless of T2D status, indicates that elevated bladder cancer risk in this group may be due to factors other than T2D. Future studies must explore reasons for this difference in incidence.

Injection fears and COVID-19 vaccine hesitancy

BACKGROUND

When vaccination depends on injection, it is plausible that the blood-injection-injury cluster of fears may contribute to hesitancy. Our primary aim was to estimate in the UK adult population the proportion of COVID-19 vaccine hesitancy explained by blood-injection-injury fears.

METHODS

In total, 15 014 UK adults, quota sampled to match the population for age, gender, ethnicity, income and region, took part (19 January-5 February 2021) in a non-probability online survey. The Oxford COVID-19 Vaccine Hesitancy Scale assessed intent to be vaccinated. Two scales (Specific Phobia Scale-blood-injection-injury phobia and Medical Fear Survey-injections and blood subscale) assessed blood-injection-injury fears. Four items from these scales were used to create a factor score specifically for injection fears.

RESULTS

In total, 3927 (26.2%) screened positive for blood-injection-injury phobia. Individuals screening positive (22.0%) were more likely to report COVID-19 vaccine hesitancy compared to individuals screening negative (11.5%), odds ratio = 2.18, 95% confidence interval (CI) 1.97-2.40, p < 0.001. The population attributable fraction (PAF) indicated that if blood-injection-injury phobia were absent then this may prevent 11.5% of all instances of vaccine hesitancy, AF = 0.11; 95% CI 0.09-0.14, p < 0.001. COVID-19 vaccine hesitancy was associated with higher scores on the Specific Phobia Scale, r = 0.22, p < 0.001, Medical Fear Survey, r = 0.23, p = <0.001 and injection fears, r = 0.25, p < 0.001. Injection fears were higher in youth and in Black and Asian ethnic groups, and explained a small degree of why vaccine hesitancy is higher in these groups.

CONCLUSIONS

Across the adult population, blood-injection-injury fears may explain approximately 10% of cases of COVID-19 vaccine hesitancy. Addressing such fears will likely improve the effectiveness of vaccination programmes.

Age- and sex-specific modifiable risk factor profiles of dementia: evidence from the UK Biobank

Dementia constitutes a worldwide concern. To characterize the age- and sex-specific modifiable risk factor profiles of dementia, we included 497,401 UK Biobank participants (mean age = 56.5 years) without dementia at baseline (2006-2010) and followed them until March 2021. Cox proportional hazard models were used to estimate the age- and sex-specific hazard ratios (HRs) of incident dementia associated with socioeconomic (less education and high Townsend deprivation index), lifestyle (non-moderate alcohol intake, current smoking, suboptimal diet, physical inactivity, and unhealthy sleep duration), and health condition factors (hypertension, diabetes, cardiovascular diseases, and depressive symptoms). We also calculated the population attributable fractions (PAFs) of these factors. During follow-up (mean = 11.6 years), we identified 6564 dementia cases. HRs for the risk factors were similar between the sexes, while most factors showed stronger associations among younger participants. For example, the HRs of smoking were 1.74 (95% CI: 1.23, 2.47) for individuals aged < 50 years, and 1.18 (1.05, 1.33) for those aged ≥ 65 years. Overall, 46.8% (37.4%, 55.2%) of dementia cases were attributable to the investigated risk factors. The PAFs of the investigated risk factors also decreased with age, but that for health condition risk factors decreased with lower magnitude than socioeconomic and lifestyle risk factors. The stronger associations and greater PAFs of several modifiable risk factors for dementia among younger adults than older participants underscored the importance of dementia prevention from an earlier stage across the adult life course.

Age-specific population attributable risk factors for all-cause and cause-specific mortality in type 2 diabetes: An analysis of a 6-year prospective cohort study of over 360,000 people in Hong Kong

BACKGROUND

The prevalence of type 2 diabetes has increased in both young and old people. We examined age-specific associations and population attributable fractions (PAFs) of risk factors for all-cause and cause-specific mortality in people with type 2 diabetes.

METHODS AND FINDINGS

We analysed data from 360,202 Chinese with type 2 diabetes who participated in a territory-wide diabetes complication screening programme in Hong Kong between January 2000 and December 2019. We compared the hazard ratios and PAFs of eight risk factors, including three major comorbidities (cardiovascular disease [CVD], chronic kidney disease [CKD], all-site cancer) and five modifiable risk factors (suboptimal HbA1c, suboptimal blood pressure, suboptimal low-density lipoprotein cholesterol, smoking, and suboptimal weight), for mortality across four age groups (18 to 54, 55 to 64, 65 to 74, and ≥75 years). During a median 6.0 years of follow-up, 44,396 people died, with cancer, CVD, and pneumonia being the leading causes of death. Despite a higher absolute mortality risk in older people (crude all-cause mortality rate: 59.7 versus 596.2 per 10,000 person-years in people aged 18 to 54 years versus those aged ≥75 years), the relative risk of all-cause and cause-specific mortality associated with most risk factors was higher in younger than older people, after mutually adjusting for the eight risk factors and other potential confounders including sex, diabetes duration, lipid profile, and medication use. The eight risk factors explained a larger proportion of mortality events in the youngest (PAF: 51.6%, 95% confidence interval [CI] [39.1%, 64.0%], p < 0.001) than the oldest (PAF: 35.3%, 95% CI [27.2%, 43.4%], p < 0.001) age group. Suboptimal blood pressure (PAF: 16.9%, 95% CI [14.7%, 19.1%], p < 0.001) was the leading attributable risk factor for all-cause mortality in the youngest age group, while CKD (PAF: 15.2%, 95% CI [14.0%, 16.4%], p < 0.001) and CVD (PAF: 9.2%, 95% CI [8.3%, 10.1%], p < 0.001) were the leading attributable risk factors in the oldest age group. The analysis was restricted to Chinese, which might affect the generalisability to the global population with differences in risk profiles. Furthermore, PAFs were estimated under the assumption of a causal relationship between risk factors and mortality. However, reliable causality was difficult to establish in the observational study.

CONCLUSIONS

Major comorbidities and modifiable risk factors were associated with a greater relative risk for mortality in younger than older people with type 2 diabetes and their associations with population mortality burden varied substantially by age. These findings highlight the importance of early control of blood pressure, which could reduce premature mortality in young people with type 2 diabetes and prevent the onset of later CKD and related mortality at older ages.

COVID-19 in people aged 18-64 in Sweden in the first year of the pandemic: Key factors for severe disease and death

Background

Studies on risk factors for severe COVID-19 in people of working age have generally not included non-working persons or established population attributable fractions (PAFs) for occupational and other factors.

Objectives

We describe the effect of job-related, sociodemographic, and other exposures on the incidence, relative risks and PAFs of severe COVID-19 in individuals aged 18-64.

Methods

We conducted a registry-based study in Swedish citizens aged 18-64 from 1 January 2020 to 1 February 2021 with respect to COVID-19-related hospitalizations and death.

Results

Of 6,205,459 persons, 272,043 (7.5%) were registered as infected, 3399 (0.05%) needed intensive care, and 620 (0.01%) died, with an estimated case fatality rate of 0.06% over the last 4-month period when testing was adequate. Non-Nordic origin was associated with a RR for need of intensive care of 3·13, 95%CI 2·91-3·36, and a PAF of 32·2% after adjustment for age, sex, work, region and comorbidities. In a second model with occupation as main exposure, and adjusted for age, sex, region, comorbidities and origin, essential workers had an RR of 1·51, 95%CI, 1·35-1·6, blue-collar workers 1·18, 95%CI 1·06-1·31, school staff 1·21, 95%CI 1·01-1·46, and health and social care workers 1·89, 95%CI 1·67-2·135) compared with people able to work from home, with altogether about 13% of the PAF associated with these occupations. Essential workers and blue-collar workers, but no other job categories had higher risk of death, adjusted RRs of 1·79, 95%CI 1·34-2·38 and 1·37, 95%CI 1·04-1·81, with adjusted PAFs of altogether 9%.

Conclusion

Among people of working age in Sweden, overall mortality and case fatality were low. Occupations that require physical presence at work were associated with elevated risk of needing intensive care for COVID-19, with 14% cases attributable to this factor, and 9% of deaths.

Associations of Childhood Maltreatment and Genetic Risks With Incident Heart Failure in Later Life

Background We aimed to determine the associations of childhood maltreatment with incident heart failure in later life and explore the potentially modifying effects of genetic risk for heart failure on the associations. Methods and Results This cohort study included adults free of heart failure at baseline enrolled between 2006 and 2010 in the UK Biobank. Childhood maltreatment was retrospectively assessed with the online Childhood Trauma Screener in 2016. Five types of childhood maltreatment (range, 0-5), including physical abuse, physical neglect, emotional abuse, emotional neglect, and sexual abuse, were combined into a total score. A weighted polygenic risk score for heart failure was constructed. Incident all-cause heart failure was prospectively ascertained via hospital inpatient and death records, followed up to May 31, 2021. A total of 153 287 adults (mean [SD] age, 55.9 [7.7] years; 43.6% male) were included. Over a median of 12.2 years (interquartile range, 11.5-12.9 years) of follow-up, 2352 participants had incident heart failure. Childhood maltreatment was associated with a greater risk of incident heart failure in a dose-response manner. One additional type of childhood maltreatment was associated with a 15% increase in the risk of developing heart failure (hazard ratio [HR], 1.15 [95% CI, 1.07-1.23]). There was no statistically significant interaction between genetic risk and childhood maltreatment (P_interaction=0.218). Among participants with high genetic risk, those with 3 to 5 types of childhood maltreatment had a double hazard (HR, 2.00 [95% CI, 1.43-2.80]) of developing heart failure when taking those without any childhood maltreatment as the reference. Conclusions Irrespective of genetic risk for heart failure, childhood maltreatment was associated with an increased risk of incident heart failure in a dose-dependent manner.

Modifiable lifestyle factors have a larger contribution to colorectal neoplasms than family history

BACKGROUND

 Screening recommendations for colorectal cancer (CRC) are mainly based on family history rather than lifestyle risk factors. We aimed to assess and compare risk factors for colorectal neoplasm (CRN) and evaluate trends in neoplasm detection rates during the three rounds of screening from 2012 to 2020 in Tianjin, China.

METHODS

This study was based on 89,535 first-recorded colonoscopies in Tianjin CRC screening program, 2012-2020. Of these, 45,380 individuals with complete family history and lifestyle factors were included for population attributable fraction (PAF) estimation.

RESULTS

 The overall detection rate of nonadvanced adenomas, advanced adenomas and CRC was 39.3%, 5.9% and 1.5%, respectively. The PAFs of current smoking, alcohol consumption, physical activity, higher BMI and family history of CRC, respectively, were 8.9%, 2.6%, 1.9%, 5.8%, and 1.1% for males with nonadvanced CRN; 12.3%, 7.3%, 4.9%, 7.2%, and 0.8% for males with advanced CRN; 3.4%, 0.4%, 2.1%, 7.8%, and 0.7% for females with nonadvanced CRN; and 4.3%, 0.2%, 8.2%, 8.5%, and -0.6% for females with advanced CRN. The PAFs of selected lifestyle factors were 19.9% for males with nonadvanced CRN, 29.0% for males with advanced CRN, 9.7% for females with nonadvanced CRN and 13.8% for females with advanced CRN.

CONCLUSIONS

 Modifiable lifestyle factors, including smoking, alcohol consumption, physical activity and BMI, have a larger contribution to CRN than family history of CRC. Our findings will provide references for developing guidelines of CRC prevention and control in China.

Smoking Attributable Risk in Multiple Sclerosis

Tobacco smoke is an important modifiable environmental risk factor for multiple sclerosis (MS) risk. The population attributable fraction (AF) of MS due to smoking can be used to assess the contribution of smoking to the risk of MS development. We conducted a matched case-control study, including individuals with MS and population-based controls. Overall, sex- and genetic risk score-stratified AF due to smoking were calculated by fitting logistic regression models. We included 9,419 individuals with MS and 9,419 population-based matched controls. At the time of MS onset 44.1% of persons with MS and 35.9% of controls ever regularly smoked of which 38.1% and 29.2% were still smoking. The overall AF was 13.1% (95%CI: 10.7 to 15.4). The AF was 10.6% (95%CI: 7.4 to 13.7) in females and 19.1% (95%CI: 13.1 to 25.1) in males. The AF was 0.6% (95%CI: 0.0 to 2) in ex-smokers. In those having human leucocyte antigen (HLA) and non-HLA risk scores above the median levels of controls, the AF was 11.4% (95%CI: 6.8 to 15.9) and 12% (95%CI: 7.7 to 16.3), respectively. The AF was 17.6% (95%CI: 10.2 to 24.9) and 18.6% (95%CI: 5.5 to 31.6) in those with HLA and non-HLA risk scores below the median levels in controls, respectively. We noticed a decline in AF in recent birth cohorts. This study indicates that at least 13% of cases of MS could be prevented through the avoidance of tobacco smoking. Considering the prevalence of MS, this represents a very large group of people in absolute number.

Association of a Healthy Lifestyle With All-Cause and Cause-Specific Mortality Among Individuals With Type 2 Diabetes: A Prospective Study in UK Biobank

OBJECTIVE

To evaluate the association of a healthy lifestyle, involving seven low-risk factors mentioned in diabetes management guidelines (no current smoking, moderate alcohol consumption, regular physical activity, healthy diet, less sedentary behavior, adequate sleep duration, and appropriate social connection), with all-cause and cause-specific mortality among individuals with type 2 diabetes.

RESEARCH DESIGN AND METHODS

This study included 13,366 participants with baseline type 2 diabetes from the UK Biobank free of cardiovascular disease (CVD) and cancer. Lifestyle information was collected through a baseline questionnaire.

RESULTS

During a median follow-up of 11.7 years, 1,561 deaths were documented, with 625 from cancer, 370 from CVD, 115 from respiratory disease, 81 from digestive disease, and 74 from neurodegenerative disease. In multivariate-adjusted model, each lifestyle factor was significantly associated with all-cause mortality, and hazard ratios associated with the lifestyle score (scoring 6-7 vs. 0-2 unless specified) were 0.42 (95% CI 0.34, 0.52) for all-cause mortality, 0.57 (0.41, 0.80) for cancer mortality, 0.35 (0.22, 0.56) for CVD mortality, 0.26 (0.10, 0.63) for respiratory mortality, and 0.28 (0.14, 0.53) for digestive mortality (scoring 5-7 vs. 0-2). In the population-attributable risk analysis, 29.4% (95% CI 17.9%, 40.9%) of deaths were attributable to a poor lifestyle (scoring 0-5). The association between a healthy lifestyle and all-cause mortality was consistent, irrespective of factors reflecting diabetes severity (diabetes duration, glycemic control, diabetes-related microvascular disease, and diabetes medication).

CONCLUSIONS

A healthy lifestyle was associated with a lower risk of all-cause mortality and mortality due to CVD, cancer, respiratory disease, and digestive disease among individuals with type 2 diabetes.

Contribution of causal factors to disease burden: how to interpret attributable fractions

What proportion of the risk in a given population is attributable to a risk factor? The population attributable fraction (PAF) answers this question. "Attributable to" is understood as "due to", which makes PAFs closely related to the concept of potential impact or potential benefits of reducing the exposure. The PAF is a tool at the border between science and decision making. PAFs are estimated based on strong assumptions and the calculations are data intensive, making them vulnerable to gaps in knowledge and data. Current misconceptions include summing up PAFs to 100% or subtracting a PAF for a factor from 100% to deduce what proportion is left to be explained or prevented by other factors. This error is related to unrecognised multicausality or shared causal responsibility in disease aetiology. Attributable cases only capture cases in excess and should be regarded as a lower bound for aetiological cases, which cannot be estimated based on epidemiological data alone (exposure-induced cases). The population level might not be relevant to discuss prevention priorities based on PAFs, for instance when exposures concentrate in a subgroup of the population, as for occupational lung carcinogens and other workplace hazards. Alternative approaches have been proposed based on absolute rather than relative metrics, such as estimating potential gains in life expectancy that can be expected from a specific policy (prevention) or years of life lost due to a specific exposure that already happened (compensation).

Estimation and inference for the population attributable risk in the presence of misclassification

Because it describes the proportion of disease cases that could be prevented if an exposure were entirely eliminated from a target population as a result of an intervention, estimation of the population attributable risk (PAR) has become an important goal of public health research. In epidemiologic studies, categorical covariates are often misclassified. We present methods for obtaining point and interval estimates of the PAR and the partial PAR (pPAR) in the presence of misclassification, filling an important existing gap in public health evaluation methods. We use a likelihood-based approach to estimate parameters in the models for the disease and for the misclassification process, under main study/internal validation study and main study/external validation study designs, and various plausible assumptions about transportability. We assessed the finite sample perf ormance of this method via a simulation study, and used it to obtain corrected point and interval estimates of the pPAR for high red meat intake and alcohol intake in relation to colorectal cancer incidence in the HPFS, where we found that the estimated pPAR for the two risk factors increased by up to 317% after correcting for bias due to misclassification.

Short-term outcomes of open surgical abdominal aortic aneurysm repair from the Dutch Surgical Aneurysm Audit

Background

The sharp decrease in open surgical repair (OSR) for abdominal aortic aneurysm (AAA) has raised concerns about contemporary postoperative outcomes. The study was designed to analyse the impact of complications on clinical outcomes within 30 days following OSR.

Methods

Patients who underwent OSR for intact AAA registered prospectively between 2016 and 2019 in the Dutch Surgical Aneurysm Audit were included. Complications and outcomes (death, secondary interventions, prolonged hospitalization) were evaluated. The adjusted relative risk (aRr) and 95 per cent confidence intervals were computed using Poisson regression. Subsequently, the population-attributable fraction (PAF) was calculated. The PAF reflects the expected percentage reduction of an outcome if a complication were to be completely prevented.

Results

A total of 1657 patients were analysed. Bowel ischaemia and renal complications had the largest impact on death (aRr 12·44 (95 per cent c.i. 7·95 to 19·84) at PAF 20 (95 per cent c.i. 8·4 to 31·5) per cent and aRr 5·07 (95 per cent c.i. 3·18 to 8.07) at PAF 14 (95 per cent c.i. 0·7 to 27·0) per cent, respectively). Arterial occlusion had the greatest impact on secondary interventions (aRr 11·28 (95 per cent c.i. 8·90 to 14·30) at PAF 21 (95 per cent c.i. 14·7 to 28·1) per cent), and pneumonia (aRr 2·52 (95 per cent c.i. 2·04 to 3·10) at PAF 13 (95 per cent c.i. 8·3 to 17·8) per cent) on prolonged hospitalization. Small effects were observed on outcomes for other complications.

Conclusion

The greatest clinical impact following OSR can be made by focusing on measures to reduce the occurrence of bowel ischaemia, arterial occlusion and pneumonia.

Residence characteristics and risk of nasopharyngeal carcinoma in southern China: A population-based case-control study

OBJECTIVES

Given the role of exposures related to residence in the development of nasopharyngeal carcinoma (NPC) has not been well explored, present study aims to investigate the magnitude and pattern of associations for NPC with lifelong residential exposures.

MATERIALS AND METHODS

We carried out a multi-center, population-based case-control study with 2533 incident NPC cases and 2597 randomly selected population controls in southern China between 2010 and 2014. We performed multivariate logistic regression to estimate odds ratios (ORs) with 95% confidence intervals (CIs) for the risk of NPC associated with residential exposures.

RESULTS

Compared with those living in a building over lifetime, risk of NPC was higher for individuals living in a cottage (OR: 1.56; 95% CI: 1.34-1.81) or in a boat (3.87; 2.07-7.21). NPC risk was also increased in individuals using wood (1.34; 1.03-1.75), coal (1.70; 1.17-2.47), or kerosene (3.58; 1.75-7.36) vs. using gas/electricity as cooking fuel; using well water (1.57; 1.34-1.83), river water (1.80; 1.47-2.21), or spring/pond/stream water (2.03; 1.70-2.41) vs. tap water for source of drinking water; living in houses with smaller-sized vs. larger windows in the bedroom (3.08; 2.46-3.86), hall (1.89; 1.55-2.31) or kitchen (1.67; 1.34-2.08); and increasing exposure to cooking smoke [(1.53; 1.20-1.94) for high exposure)] or burned incense [(1.59; 1.31-1.95) for daily use)]. Weighted Cox regression analysis corroborated these results.

CONCLUSION

Poorer residential conditions and household air pollution are associated with an increased risk of NPC. Large-scale studies in other populations or longitudinal studies are warranted to further corroborate these findings.

Cardiovascular Risk Factors and Coronary Calcification in a Middle-aged Dutch Population: The ImaLife Study

PURPOSE

To assess the presence of coronary artery calcium (CAC) and its association with cardiovascular risk factors and Systematic COronary Risk Evaluation (SCORE) risk in a middle-aged Dutch population.

METHODS

Classic cardiovascular risk factors and CAC were analyzed in 4083 participants aged 45 to 60 years (57.9% women) from the population-based ImaLife study. CAC scores were quantified on noncontrast cardiac CT scans. Age-specific and sex-specific distribution of CAC categories (0, 1 to 99, 100 to 299, ≥300) and percentiles were determined. SCORE risk categories (<1%, ≥1% to 5%, and ≥5%) were compared with CAC distribution. Population attributable fractions (PAFs) of classic risk factors for CAC were estimated.

RESULTS

CAC was present in 54.5% male and 26.5% female participants. The percentage of individuals with CAC increased with increasing age. Mean SCORE was 2.0% in men and 0.7% in women. In SCORE <1%, 32.7% of men and 17.1% of women had CAC. In men with SCORE ≥5%, 26.9% had no CAC. Only 0.1% of women had SCORE ≥5%. PAF of classic risk factors for CAC was 18.5% in men and 31.4% in women. PAF was highest for hypertension (in men 8.0%, 95% confidence interval, 4.2%-11.8%; in women 13.1%, 95% confidence interval, 7.9%-18.2%) followed by hypercholesterolemia and obesity.

CONCLUSION

In this middle-aged cohort, more than half of the men and a quarter of the women had CAC. One out of 4 men at high risk (SCORE ≥5%) could be placed into a lower risk category owing to absence of CAC. Thus, adding CAC scoring to SCORE could have considerable effect on cardiovascular risk classification. Elimination of exposure to classic risk factors could reduce limited proportion of CAC in a middle-aged population.

Investigation of the Association between 45 Tag SNPs and Type 2 Diabetes Mellitus in Han Chinese Adults: A Prospective Cohort Study

INTRODUCTION

The objective of this study was to examine the association between type 2 diabetes mellitus (T2DM) and genes identified in previous genome-wide association studies (GWASs) in rural Han Chinese adults.

METHODS

This prospective study included 1,832 adults aged ≥18 years in Deqing without diabetes at baseline. The subjects were followed up for 8.7 years on average. We selected 45 susceptible tag single-nucleotide polymorphisms (SNPs) for T2DM that have been identified in GWASs and genotyped. A Cox model was constructed to calculate the adjusted hazard ratios (aHRs) for the association between SNPs and incident T2DM.

RESULTS

The incidence rate of T2DM was 12.0 per 1,000 person-years. After adjustment for covariates and a Bonferroni correction, rs17584499 of protein tyrosine phosphatase, receptor-type D (PTPRD), rs11257655 and rs10906115 of cell division cycle 123 gene (CDC123), and rs12970134 of melanocortin-4 receptor (MC4R) were significantly associated with incident T2DM. The aHRs for incident T2DM were 1.75 (95% confidence interval [CI]: 1.28-2.40) and 1.61 (95% CI: 1.27-2.04) in association with an increasing number of T alleles in rs17584499 and rs11257655 under an additive genetic model, and the aHR was 1.72 (95% CI: 1.33-2.22) with an increasing number of A alleles in rs10906115. The aHRs under the dominant model were 1.82 (95% CI: 1.25-2.66) for TT + CT versus CC of rs17584499 and 2.04 (95% CI: 1.47-2.86) for AA + AG versus GG of rs10966115. The aHRs under the recessive model were 2.99 (95% CI: 1.30-6.89) for TT versus CT + CC of rs17584499, 1.92 (95% CI: 1.39-2.70) for TT versus CT + CC of rs11257655, and 2.54 (95% CI:1.22-5.29) for AA versus AG + GG of rs12970134. In addition, an increased incidence of T2DM was significantly associated with the TA haplotype of rs11257655 and rs10906115 (aHR = 1.81, 95% CI: 1.12-2.92), while a decreased incidence was associated with the CG haplotype (aHR = 0.49, 95% CI: 0.35-0.68) and the CT haplotype of rs1111875 and rs5015480 (aHR = 0.61, 95% CI: 0.37-0.98).

CONCLUSION

Variants of the PTPRD, CDC123, and MC4R genes were associated with the T2DM incidence in a rural Han Chinese population.

Population attributable risk of excess weight, abdominal obesity and physical inactivity for type 2 diabetes in Chinese men and women

Background

Given the high prevalence of type 2 diabetes mellitus (T2DM) in the Chinese population, it is necessary to estimate the T2DM incident attributable to obesity and physical inactivity.

Methods

We analyzed the data from the Shanghai Men's and Women's Health Studies, including 56,691 men and 70,849 women aged 40-74. The hazard ratios (HRs) and the population attributable risks (PARs) were calculated by Cox regression model and model-based estimation.

Results

A total of 3,315 male and 5,925 female cases were identified during 519,157 and 981,504 person-years, up to 31 December 2017. Excess weight, abdominal obesity were associated with the increased risks of T2DM both in women and men, while physical inactivity was only associated with an increased risk in men. A large proportion of T2DM incident cases can be attributed to excess body weight (women: 48.6%; men: 41.5%) and abdominal obesity (women: 50.4%; men: 30.3%). Physical activity was negatively associated with the risk of T2DM (P_trend<0.01). The PARs adjusted for confounders were 3.6% for physical inactivity in men and 1.7% in women.

Conclusions

Excess weight and abdominal obesity accounted for a large proportion of T2DM incident cases in men and women; a small part of T2DM cases were attributed to physical inactivity in men. Weight control is of great significance in curbing the epidemic of diabetes.

Pan-cancer analysis demonstrates that integrating polygenic risk scores with modifiable risk factors improves risk prediction

Cancer risk is determined by a complex interplay of environmental and heritable factors. Polygenic risk scores (PRS) provide a personalized genetic susceptibility profile that may be leveraged for disease prediction. Using data from the UK Biobank (413,753 individuals; 22,755 incident cancer cases), we quantify the added predictive value of integrating cancer-specific PRS with family history and modifiable risk factors for 16 cancers. We show that incorporating PRS measurably improves prediction accuracy for most cancers, but the magnitude of this improvement varies substantially. We also demonstrate that stratifying on levels of PRS identifies significantly divergent 5-year risk trajectories after accounting for family history and modifiable risk factors. At the population level, the top 20% of the PRS distribution accounts for 4.0% to 30.3% of incident cancer cases, exceeding the impact of many lifestyle-related factors. In summary, this study illustrates the potential for improving cancer risk assessment by integrating genetic risk scores.

Antecedent febrile illness and occurrence of stroke in West Africa: The SIREN study

BACKGROUND

Acute infections have been posited as potential precipitants or triggers of the occurrence of stroke among adults with traditional vascular risk factors. We evaluated associations between stroke occurrence and reported febrile illness within 4 weeks (potential antecedent infections) among West Africans.

METHODS

The Stroke Investigative Research and Educational Network (SIREN) is a multicenter, case-control study involving 15 sites in Ghana and Nigeria. Cases include adults aged ≥18 years with radiologically confirmed strokes. Controls were stroke-free adults matched with cased by age, gender and ethnicity. Detailed evaluations for vascular, lifestyle and psychosocial factors were performed. Participants were asked for evidence of any febrile illness within the past 4 weeks. We used conditional logistic regression to estimate adjusted odds ratios (aOR) with 95% Confidence Interval.

RESULTS

Among 3588 stroke cases recruited in Ghana and Nigeria between August 2014 and July 2018, 363 cases (10.1%) reported having a febrile illness within the 4 weeks prior to stroke occurrence. Having an antecedent infection was associated with stroke occurrence with an unadjusted OR of 1.19 (1.00-1.51) but aOR of 0.83 (0.59-1.17) upon adjusting for traditional vascular risk factors. Stress, aOR of 4.69 (2.59-8.50) and consumption of green vegetables 2.27 (1.35-2.85) were associated with antecedent febrile illness.

CONCLUSION

1 in 10 stroke cases reported antecedent history of febrile illness prior to occurrence of stroke but no independent association was observed in this study. Infectious exposures may be important triggers of cardiovascular events requiring further exploratory studies to better understand the role of this emerging risk factor.

Adolescent Opioid Misuse Attributable to Adverse Childhood Experiences

OBJECTIVES

To estimate the proportion of opioid misuse attributable to adverse childhood experiences (ACEs) among adolescents.

STUDY DESIGN

A cross-sectional survey was administered to 10 546 seventh-to twelfth-grade students in northeastern Ohio in Spring 2018. Study measures included self-reported lifetime exposure to 10 ACEs and past 30-day use of nonmedical prescription opioid or heroin. Using generalized estimating equations, we evaluated associations between recent opioid misuse, individual ACEs, and cumulative number of ACEs. We calculated population attributable fractions to determine the proportion of adolescents' recent opioid misuse attributable to ACEs.

RESULTS

Nearly 1 in 50 adolescents reported opioid misuse within 30 days (1.9%); approximately 60% of youth experienced ≥1 ACE; 10.2% experienced ≥5 ACEs. Cumulative ACE exposure demonstrated a significant graded relationship with opioid misuse. Compared with youth with zero ACEs, youth with 1 ACE (aOR 1.9, 95% CI, 0.9-3.9), 2 ACEs (aOR, 3.8; 95% CI, 1.9-7.9), 3 ACEs (aOR, 3.7; 95% CI, 2.2-6.5), 4 ACEs (aOR, 5.8; 95% CI, 3.1-11.2), and ≥5 ACEs (aOR, 15.3; 95% CI, 8.8-26.6) had higher odds of recent opioid misuse. The population attributable fraction of recent opioid misuse associated with experiencing ≥1 ACE was 71.6% (95% CI, 59.8-83.5).

CONCLUSIONS

There was a significant graded relationship between number of ACEs and recent opioid misuse among adolescents. More than 70% of recent adolescent opioid misuse in our study population was attributable to ACEs. Efforts to decrease opioid misuse could include programmatic, policy, and clinical practice interventions to prevent and mitigate the negative effects of ACEs.

Differential Impact of Risk Factors on Stroke Occurrence Among Men Versus Women in West Africa

Background and Purpose- The interplay between sex and the dominant risk factors for stroke occurrence in sub-Saharan Africa has not been clearly delineated. We compared the effect sizes of risk factors of stroke by sex among West Africans. Methods- SIREN study (Stroke Investigative Research and Educational Networks) is a case-control study conducted at 15 sites in Ghana and Nigeria. Cases were adults aged >18 years with computerized tomography/magnetic resonance imaging confirmed stroke, and controls were age- and sex-matched stroke-free adults. Comprehensive evaluation for vascular, lifestyle, and psychosocial factors was performed using validated tools. We used conditional logistic regression to estimate odds ratios and reported risk factor specific and composite population attributable risks with 95% CIs. Results- Of the 2118 stroke cases, 1193 (56.3%) were males. The mean±SD age of males was 58.1±13.2 versus 60.15±14.53 years among females. Shared modifiable risk factors for stroke with adjusted odds ratios (95% CI) among females versus males, respectively, were hypertension [29.95 (12.49-71.77) versus 16.1 0(9.19-28.19)], dyslipidemia [2.08 (1.42-3.06) versus 1.83 (1.29-2.59)], diabetes mellitus [3.18 (2.11-4.78) versus 2.19 (1.53-3.15)], stress [2.34 (1.48-3.67) versus 1.61 (1.07-2.43)], and low consumption of green leafy vegetables [2.92 (1.89-4.50) versus 2.00 (1.33-3.00)]. However, salt intake and income were significantly different between males and females. Six modifiable factors had a combined population attributable risk of 99.1% (98.3%-99.6%) among females with 9 factors accounting for 97.2% (94.9%-98.7%) among males. Hemorrhagic stroke was more common among males (36.0%) than among females (27.6%), but stroke was less severe among males than females. Conclusions- Overall, risk factors for stroke occurrence are commonly shared by both sexes in West Africa favoring concerted interventions for stroke prevention in the region.

Identification of the clinically most relevant postoperative complications after gastrectomy: a population-based cohort study

BACKGROUND

Postoperative complications frequently occur after gastrectomy for gastric cancer and are associated with poor clinical outcomes, such as mortality and reoperations. The aim of study was to identify the clinically most relevant complications after gastrectomy, using the population-attributable fraction (PAF).

METHODS

Between 2011 and 2017, all patients who underwent potentially curative gastrectomy for gastric adenocarcinoma were included from the Dutch Upper GI Cancer Audit. Postoperative outcomes (morbidity, mortality, recovery and hospitalization) were evaluated. The prevalence of postoperative complications (e.g., anastomotic leakage and pneumonia) and of the study outcomes were calculated. The adjusted relative risk and Confidence Interval (CI) for each complication-outcome pair were calculated. Subsequently, the PAF was calculated, which represents the percentage of a given outcome occurring in the population, caused by individual complications, taking both the relative risk and the frequency in which a complication occurs into account.

RESULTS

In total, 2176 patients were analyzed. Anastomotic leakage and pulmonary complications had the greatest overall impact on postoperative mortality (PAF 29.2% [95% CI 19.3-39.1] and 21.6% [95% CI 10.5-32.7], respectively) and prolonged hospitalization (PAF 12.9% [95% CI 9.7-16.0] and 14.7% [95% CI 11.0-18.8], respectively). Anastomotic leakage had the greatest overall impact on re-interventions (PAF 25.1% [95% CI 20.5-29.7]) and reoperations (PAF 30.3% [95% CI 24.3-36.3]). Intra-abdominal abscesses had the largest impact on readmissions (PAF 7.0% [95% CI 3.2-10.9]). Other complications only had a small effect on these outcomes.

CONCLUSION

Surgical improvement programs should focus on preventing or managing anastomotic leakage and pulmonary complications, since these complications have the greatest overall impact on clinical outcomes after gastrectomy.

Using instrumental variables to estimate the attributable fraction

In order to design efficient interventions aimed to improve public health, policy makers need to be provided with reliable information of the health burden of different risk factors. For this purpose, we are interested in the proportion of cases that could be prevented had some harmful exposure been eliminated from the population, i.e. the attributable fraction. The attributable fraction is a causal measure; thus, to estimate the attributable fraction from observational data, we have to make appropriate adjustment for confounding. However, some confounders may be unobserved, or even unknown to the investigator. A possible solution to this problem is to use instrumental variable analysis. In this work, we present how the attributable fraction can be estimated with instrumental variable methods based on the two-stage estimator or the G-estimator. One situation when the problem of unmeasuredconfounding may be particularly severe is when assessing the effect of low educational qualifications on coronary heart disease. By using Mendelian randomization, a special case of instrumental variable analysis, it has been claimed that low educational qualifications is a causal risk factor for coronary heart disease. We use Mendelian randomization to estimate the causal risk ratio and causal odds ratio of low educational qualifications as a risk factor for coronary heart disease with data from the UK Biobank. We compare the two-stage and G-estimator as well as the attributable fraction based on the two estimators. The plausibility of drawing causal conclusion in this analysis is thoroughly discussed and alternative genetic instrumental variables are tested.

Mortality and potential years of life lost attributable to non-optimal glycaemic control in men and women with diabetes in the United Arab Emirates: a population-based retrospective cohort study

OBJECTIVES

Numerous studies reported that achieving near-normal glycated haemoglobin (HbA1c) levels in patients with diabetes may delay or even prevent vascular complications. However, information regarding the impact of non-optimal HbA1c control on adverse health outcomes in an Arab population is unknown. The aim of this study was to estimate the fraction of deaths and potential years of life lost (PYLL) attributable to non-optimal HbA1c control among Emirati men and women with diabetes in the United Arab Emirates (UAE).

DESIGN

A retrospective cohort study.

SETTING

This study was conducted in outpatient clinics at a tertiary care centre in Al Ain, UAE, between April 2008 and September 2018.

PARTICIPANTS

The sample comprised of 583 adult UAE nationals, aged≥18 years, with diabetes. Overall, 57% (n=332) of the study participants were men and 43% (n=251) were women.

EXPOSURE

Non-optimal HbA1c control, defined as HbA1c≥6.5%.

PRIMARY OUTCOME MEASURE

All-cause mortality, defined as death from any cause.

RESULTS

At the end of the 9-year follow-up period, 86 (14.8%) participants died. Overall, up to 33% (95% CI 2% to 63%) of deaths were attributable to non-optimal HbA1c control among patients with diabetes mellitus (DM). Stratified by sex, the adjusted fraction of avoidable mortality was 17% (95% CI -23% to 57%) for men and 50% (95% CI 3% to 98%) for women. Both deaths and PYLL attributable to non-optimal HbA1c control were higher in women compared with men.

CONCLUSIONS

Up to one-third of all deaths in adult UAE nationals with DM could be attributed to non-optimal HbA1c control. Effective sex-specific interventions and healthcare quality-improvement programmes should urgently be implemented.

Two-Thirds of All Fractures Are Not Attributable to Osteoporosis and Advancing Age: Implications for Fracture Prevention

CONTEXT

Although bone mineral density (BMD) is strongly associated with fracture and postfracture mortality, the burden of fractures attributable to low BMD has not been investigated.

OBJECTIVES

We sought to estimate the population attributable fraction of fractures and fracture-related mortality that can be attributed to low BMD.

DESIGN AND SETTING

This study is a part of an ongoing population-based prospective cohort study, the Dubbo Osteoporosis Epidemiology study. In total, 3700 participants aged ≥50 years participated in the study. Low-trauma fracture was ascertained by X-ray reports, and mortality was ascertained from the Birth, Death and Marriage Registry.

RESULTS

Overall, 21% of women and 11% of men had osteoporotic BMD. In univariable analysis, 21% and 16% of total fractures in women and men, respectively, were attributable to osteoporosis. Osteoporosis combined with advancing age (>70 years) accounted for 34% and 35% of fractures in women and men, respectively. However, these two factors accounted for ∼60% of hip fractures. About 99% and 66% of postfracture mortality in women and men, respectively, were attributable to advancing age, osteoporosis, and fracture; however, most of the attributable proportion was accounted for by advancing age.

CONCLUSIONS

A substantial health care burden of fracture is on people aged <70 years or nonosteoporosis, suggesting that treatment of people with osteoporosis is unlikely to reduce a large number of fractures in the general population.

Adverse perinatal outcomes for obese women are influenced by the presence of comorbid diabetes and hypertensive disorders

Maternal obesity often occurs together with comorbid diabetes and hypertensive disorders. All three conditions are independently associated with negative perinatal outcomes. Our objective was to determine the risk and burden of adverse perinatal outcome that could be attributed to maternal obesity in combination with a comorbid status. We analyzed data from 324'664 singleton deliveries in Switzerland between 2005 and 2016. For the association of maternal obesity in the presence or absence of comorbidities with various perinatal outcomes, we estimated adjusted relative risk (RR) using multivariable regression modeling and determined the multivariable-adjusted attributable fraction of the population (AFp). Obesity was a main predictor for macrosomia, fracture of the clavicle, failure to progress in labor and prolonged labor. By stratifying women based on comorbidities, we identified significantly increased risk for preterm birth and early neonatal death only for women diagnosed with a comorbidity. However, various other outcomes were independently associated with either obesity or comorbidities. The AFp showed greatest reduction in comorbidities (15.4/15.0/13.2%), in macrosomia (6.3%) and in shoulder dystocia (4.8%) if all women were to become non-obese. We suggest that comorbidities such as diabetes and hypertensive disorders should be considered when relating maternal obesity to adverse perinatal outcomes.

Misuse of Regression Adjustment for Additional Confounders Following Insufficient Propensity Score Balancing

After propensity score (PS) matching, inverse probability weighting, and stratification or regression adjustment for PS, one may compare different exposure groups with or without further covariate adjustment. In the former case, although a typical application uses the same set of covariates in the PS and the stratification post-PS balancing, several studies adjust for additional confounders in the stratification while ignoring the covariates that have been balanced by the PS. We show the bias arising from such partial adjustments for distinct sets of confounders by PS and regression or stratification. Namely, the stratification or regression after PS balancing causes imbalance in the confounders that have been balanced by the PS if PS-balanced confounders are ignored. We empirically illustrate the bias in the Rotterdam Tumor Bank, in which strong confounders distort the association between chemotherapy and recurrence-free survival. If additional covariates are adjusted for after PS balancing, the covariate sets conditioned in PS should be again adjusted for, or PS should be reestimated by including the additional covariates to avoid bias owing to covariate imbalance.

Genome sequencing analysis identifies Epstein-Barr virus subtypes associated with high risk of nasopharyngeal carcinoma

Epstein-Barr virus (EBV) infection is ubiquitous worldwide and is associated with multiple cancers, including nasopharyngeal carcinoma (NPC). The importance of EBV viral genomic variation in NPC development and its striking epidemic in southern China has been poorly explored. Through large-scale genome sequencing of 270 EBV isolates and two-stage association study of EBV isolates from China, we identified two non-synonymous EBV variants within BALF2 strongly associated with the risk of NPC (odds ratio (OR) = 8.69, P=9.69×10⁻²⁵ for SNP 162476_C; OR = 6.14, P=2.40×10⁻³² for SNP 163364_T). The cumulative effects of these variants contributed to 83% of the overall risk of NPC in southern China. Phylogenetic analysis of the risk variants revealed a unique origin in Asia, followed by clonal expansion in NPC-endemic regions. Our results provide novel insights into NPC endemic in southern China and also enable the identification of high-risk individuals for NPC prevention.

Whole-genome sequencing and association analysis of 270 Epstein-Barr virus (EBV) isolates from China identify two non-synonymous EBV variants within BALF2 strongly associated with the risk of nasopharyngeal carcinoma.

The population-attributable fraction for time-dependent exposures and competing risks-A discussion on estimands

The population-attributable fraction (PAF) quantifies the public health impact of a harmful exposure. Despite being a measure of significant importance, an estimand accommodating complicated time-to-event data is not clearly defined. We discuss current estimands of the PAF used to quantify the public health impact of an internal time-dependent exposure for data subject to competing outcomes. To overcome some limitations, we proposed a novel estimand that is based on dynamic prediction by landmarking. In a profound simulation study, we discuss interpretation and performance of the various estimands and their estimators. The methods are applied to a large French database to estimate the health impact of ventilator-associated pneumonia for patients in intensive care.

Low-trauma rib fracture in the elderly: Risk factors and mortality consequence

PURPOSE

Low trauma rib fracture (hereinafter, rib fracture) is common in the elderly, but its risk factors and mortality consequence are rarely studied. We sought to define the epidemiology of rib fracture and the association between rib fracture and postfracture mortality.

METHODS

The study was part of the Dubbo Osteoporosis Epidemiology Study, which was designed as a population-based prospective study, and consisted of 2041 women and men (aged ≥ 60). The incidence of rib fracture was ascertained from X-ray reports. Bone mineral density (BMD) was measured by DXA (GE-Lunar). The time-dependent Cox model was used to access the relationship between rib fracture and mortality.

RESULTS

During the median follow-up of 13 years, 59 men and 78 women had sustained a rib fracture, making the annual incidence of 4.8/1000 person-years. Each SD (0.15 g/cm²) lower in femoral neck BMD was associated with ~2-fold increase in the hazard of fracture (hazard ratio [HR] 1.9; 95% CI, 1.4 to 2.6 in men; and HR 2.1; 95% CI, 1.6 to 2.8 in women). Among those with a rib fracture, the incidence of subsequent fractures was 10.2/100 person-years. Compared with those without a fracture, the risk of mortality among those with a fracture was increased by ~7.8-fold (95% CI, 2.7 to 22.5) in men and 4.9-fold (95% CI 2.0 to 11.8) in women within the first year postfracture.

CONCLUSIONS

A rib fracture signifies an increased risk of subsequent fractures and mortality. The increased risk of mortality during the first 2.5 years postfracture suggests a window of opportunity for treatment.

Impact of postoperative complications on outcomes after oesophagectomy for cancer

BACKGROUND

To allocate healthcare resources optimally, complication-related quality initiatives should target complications that have the greatest overall impact on outcomes after surgery. The aim of this study was to identify the most clinically relevant complications after oesophagectomy for cancer in a nationwide cohort study.

METHODS

Consecutive patients who underwent oesophagectomy for cancer between January 2011 and December 2016 were identified from the Dutch Upper Gastrointestinal Cancer Audit. The adjusted population attributable fraction (PAF) was used to estimate the impact of specific postoperative complications on the clinical outcomes postoperative mortality, reoperation, prolonged hospital stay and readmission to hospital in the study population. The PAF represents the percentage reduction in the frequency of a given outcome (such as death) that would occur in a theoretical scenario where a specific complication (for example anastomotic leakage) was able to be prevented completely in the study population.

RESULTS

Some 4096 patients were analysed. Pulmonary complications and anastomotic leakage had the greatest overall impact on postoperative mortality (risk-adjusted PAF 44·1 and 30·4 per cent respectively), prolonged hospital stay (risk-adjusted PAF 31·4 and 30·9 per cent) and readmission to hospital (risk-adjusted PAF 7·3 and 14·7 per cent). Anastomotic leakage had the greatest impact on reoperation (risk-adjusted PAF 47·1 per cent). In contrast, the impact of other complications on these outcomes was relatively small.

CONCLUSION

Reducing the incidence of pulmonary complications and anastomotic leakage may have the greatest clinical impact on outcomes after oesophagectomy.

Outcome after stroke attributable to baseline factors-The PROSpective Cohort with Incident Stroke (PROSCIS)

Background

The impact of risk factors on poor outcome after ischemic stroke is well known, but estimating the amount of poor outcome attributable to single factors is challenging in presence of multimorbidity. We aim to compare population attributable risk estimates obtained from different statistical approaches regarding their consistency. We use a real-life data set from the PROSCIS study to identify predictors for mortality and functional impairment one year after first-ever ischemic stroke and quantify their contribution to poor outcome using population attributable risks.

Methods

The PROSpective Cohort with Incident Stroke (PROSCIS) is a prospective observational hospital-based cohort study of patients after first-ever stroke conducted independently in Berlin (PROSCIS-B) and Munich (PROSCIS-M). The association of baseline factors with poor outcome one year after stroke in PROSCIS-B was analysed using multiple logistic regression analysis and population attributable risks were calculated, which were estimated using sequential population attributable risk based on a multiple generalized additive regression model, doubly robust estimation, as well as using average sequential population attributable risk. Findings were reproduced in an independent validation sample from PROSCIS-M.

Results

Out of 507 patients with available outcome information after 12 months in PROSCIS-B, 20.5% suffered from poor outcome. Factors associated with poor outcome were age, pre-stroke physical disability, stroke severity (NIHSS), education, and diabetes mellitus. The order of risk factors ranked by magnitudes of population attributable risk was almost similar for all methods, but population attributable risk estimates varied markedly between the methods. In PROSCIS-M, incidence of poor outcome and distribution of baseline parameters were comparable. The multiple logistic regression model could be reproduced for all predictors, except pre-stroke physical disability. Similar to PROSCIS-B, the order of risk factors ranked by magnitudes of population attributable risk was almost similar for all methods, but magnitudes of population attributable risk differed markedly between the methods.

Conclusions

Ranking of risk factors by population impact is not affected by the different statistical approaches. Thus, for a rational decision on which risk factor to target in disease interventions, population attributable risk is a supportive tool. However, population attributable risk estimates are difficult to interpret and are not comparable when they origin from studies applying different methodology. The predictors for poor outcome identified in PROSCIS-B have a relevant impact on mortality and functional impairment one year after first-ever ischemic stroke.