Project description:BackgroundThe causal relationship between certain lifestyle factors and erectile dysfunction (ED) is still uncertain.AimThe study sought to investigate the causal effect of 9 life factors on ED through 2-sample single-variable Mendelian randomization (SVMR) and multivariable Mendelian randomization (MVMR).MethodsGenetic instruments to proxy 9 risk factors were identified by genome-wide association studies. The genome-wide association studies estimated the connection of these genetic variants with ED risk (n = 223 805). We conducted SVMR, inverse variance-weighting, Cochran's Q, weighted median, MR-Egger, MR-PRESSO (Mendelian Randomization Pleiotropy RESidual Sum and Outlier), and MVMR analyses to explore the total and direct relationship between life factors and ED.OutcomesThe primary outcome was defined as self or physician-reported ED, or using oral ED medication, or a history of surgery related to ED.ResultsIn SVMR analyses, suggestive associations with increased the risk of ED were noted for ever smoked (odds ratio [OR], 5.894; 95% confidence interval [CI], 0.469 to 3.079; P = .008), alcohol consumption (OR, 1.495; 95% CI, 0.044 to 0.760; P = .028) and body mass index (BMI) (OR, 1.177; 95% CI, 0.057 to 0.268; P = .003). Earlier age at first intercourse was significantly related to reduced ED risk (OR, 0.659; 95% CI, -0.592 to -0.244; P = 2.5 × 10-6). No strong evidence was found for the effect of coffee intake, time spent driving, physical activity, and leisure sedentary behaviors on the incidence of ED (All P > .05). The result of MVMR analysis for BMI (OR, 1.13; 95% CI, 1.01 to 1.25; P = .045) and earlier age at first intercourse (OR, 0.77; 95% CI, 0.56 to 0.99; P = .018) provided suggestive evidence for the direct impact on ED, while no causal factor was detected for alcoholic drinks per week and ever smoked.Clinical implicationsThis study provides evidence for the impact of certain modifiable lifestyle factors on the development of ED.Strengths and limitationsWe performed both SVMR and MVMR to strengthen the causal relationship between exposures and outcomes. However, the population in this study was limited to European ancestry.ConclusionEver smoked, alcoholic drinks per week, BMI, and age first had sexual intercourse were causally related to ED, while the potential connection between coffee intake, physical activity, recreational sedentary habits, and increased risk of ED needs to be further confirmed.
Project description:Evening chronotype associates with health complications possibly via lifestyle factors, while the contribution of genetics is unknown. The aim was to study the relative contributions of genetics, lifestyle, and circadian-related physiological characteristics in metabolic risk of evening chronotype. In order to capture a biological contribution to chronotype, a genetic-risk-score (GRS), comprised of 15 chronotype-related variants, was tested. Moreover, a wide range of behavioral and emotional eating factors was studied within the same population. Chronotype, lifestyle, and metabolic syndrome (MetS) outcomes were assessed (n = 2,126), in addition to genetics (n = 1,693) and rest-activity/wrist-temperature rhythms (n = 100). Evening chronotype associated with MetS and insulin resistance (P < 0.05), and several lifestyle factors including poorer eating behaviors, lower physical activity and later sleep and wake times. We observed an association between higher evening GRS and evening chronotype (P < 0.05), but not with MetS. We propose a GRS as a tool to capture the biological component of the inter-individual differences in chronotype. Our data show that several modifiable factors such as sedentary lifestyle, difficulties in controlling the amount of food eaten, alcohol intake and later wake and bed times that characterized evening-types, may underlie chronotype-MetS relationship. Our findings provide insights into the development of strategies, particularly for evening chronotype.
Project description:Although many strong risk factors for osteoporosis-such as family history, fracture history and age-are not modifiable, a number of important risk factors are potential targets for intervention. Thus, simple, non-pharmacological intervention in patients at increased risk of osteoporotic fractures could include reduction of excessive alcohol intake, smoking cessation, adequate nutrition, patient education, daily physical activity and a careful review of medications that could increase the risk of falls and fractures. There remains, however, an unmet need for high-quality intervention studies in most of these areas.
Project description:IntroductionThe associations of modifiable lifestyle risk factors with incident diabetes are not well investigated in African Americans (AAs). This study investigated the association of modifiable lifestyle risk factors (exercise, diet, smoking, TV watching, and sleep-disordered breathing burden) with incident diabetes among AAs.MethodsModifiable lifestyle risk factors were characterized among 3,252 AAs in the Jackson Heart Study who were free of diabetes at baseline (2000-2004) using baseline questionnaires and combined into risk factor categories: poor (0-3 points), average (4-7 points), and optimal (8-11 points). Incidence rate ratios (IRR) for diabetes (fasting glucose ≥126 mg/dL, physician diagnosis, use of diabetes drugs, or glycosylated hemoglobin A1c ≥6.5%) were estimated using Poisson regression modeling adjusting for age, sex, education, occupation, systolic blood pressure, and BMI. Outcomes were collected 2005-2012 and data analyzed in 2016.ResultsOver 7.6 years, there were 560 incident diabetes cases (mean age=53.3 years, 64% female). An average or optimal compared to poor risk factor categorization was associated with a 21% (IRR=0.79, 95% CI=0.62, 0.99) and 31% (IRR=0.69, 95% CI=0.48, 1.01) lower risk of diabetes. Among participants with BMI <30, IRRs for average or optimal compared to poor categorization were 0.60 (95% CI=0.40, 0.91) and 0.53 (95% CI=0.29, 0.97) versus 0.90 (95% CI=0.67, 1.21) and 0.83 (95% CI=0.51, 1.34) among participants with BMI ≥30.ConclusionsA combination of modifiable lifestyle factors are associated with a lower risk of diabetes among AAs, particularly among those without obesity.
Project description:Background and purposeAssessing whether modifiable risk factors are causally associated with stroke risk is important in planning public health measures, but determining causality can be difficult in epidemiological data. We evaluated whether modifiable lifestyle factors including educational attainment, smoking, and body mass index are causal risk factors for ischemic stroke and its subtypes and hemorrhagic stroke.MethodsWe performed 2-sample and multivariable Mendelian randomization to assess the causal effect of 12 lifestyle factors on risk of stroke and whether these effects are independent.ResultsGenetically predicted years of education was inversely associated with ischemic, large artery, and small vessel stroke, and intracerebral hemorrhage. Genetically predicted smoking, body mass index, and waist-hip ratio were associated with ischemic and large artery stroke. The effects of education, body mass index, and smoking on ischemic stroke were independent.ConclusionsOur findings support the hypothesis that reduced education and increased smoking and obesity increase risk of ischemic, large artery, and small vessel stroke, suggesting that lifestyle modifications addressing these risk factors will reduce stroke risk.
Project description:While clinical trials have reported beneficial effects of diet, exercise, and weight loss on incident diabetes in subjects with obesity or impaired glucose tolerance, little is known about the incremental benefit of not smoking and moderate drinking on diabetes risk. We sought to examine the association between modifiable lifestyle factors and residual lifetime risk of diabetes.Prospective cohorts involving 20,915 men (1982-2008) and 36,594 women (1992-2008). Modifiable lifestyle factors and adiposity were ascertained at baseline in each cohort and incident diabetes was ascertained during follow up. The mean age at baseline was 53.5 y in men and 54.6 y in women. During an average follow up of 22.6 y in men and 13.0 y in women, 2096 men and 2390 women developed diabetes. At age 45 y, the residual lifetime risk of diabetes (95% CI) for men with 0, 1, 2, 3, and 4 + healthy lifestyle factors was 30.5 (27.3-33.7); 21.5 (19.9-23.0); 15.1 (13.9-16.3); 10.3 (9.1-11.5); and 7.3 (5.7-8.9) percent; respectively. Corresponding values for women were 31.4 (28.3-34.5); 24.1 (21.8-26.5); 14.2 (12.7-15.7); 11.6 (9.7-13.5); and 6.4 (4.2-8.6) percent, respectively.These data show an inverse and graded relation between desirable lifestyle factors and residual lifetime risk of diabetes in men and women. Not smoking and moderate drinking may have additional benefits when added to exercise, weight control, and diet.
Project description:The lifetime risk of heart failure at age 40 years is approximately 1 in 5 in the general population; however, little is known about the association between modifiable lifestyle factors and the remaining lifetime risk of heart failure.To examine the association between modifiable lifestyle factors and the lifetime risk of heart failure in a large cohort of men.Prospective cohort study using data from 20,900 men (mean age at baseline, 53.6 years) from the Physicians' Health Study I (1982-2008) who were apparently healthy at baseline. Six modifiable lifestyle factors were assessed: body weight, smoking, exercise, alcohol intake, consumption of breakfast cereals, and consumption of fruits and vegetables.Lifetime risk of heart failure.During a mean follow-up of 22.4 years, 1200 men developed heart failure. Overall, the lifetime risk of heart failure was 13.8% (95% confidence interval [CI], 12.9%-14.7%) at age 40 years. Lifetime risk remained constant in men who survived free of heart failure through age 70 years and reached 10.6% (95% CI, 9.4%-11.7%) at age 80 years. Lifetime risk of heart failure was higher in men with hypertension than in those without hypertension. Healthy lifestyle habits (normal body weight, not smoking, regular exercise, moderate alcohol intake, consumption of breakfast cereals, and consumption of fruits and vegetables) were individually and jointly associated with a lower lifetime risk of heart failure, with the highest risk in men adhering to none of the 6 lifestyle factors (21.2%; 95% CI, 16.8%-25.6%) and the lowest risk in men adhering to 4 or more desirable factors (10.1%; 95% CI, 7.9%-12.3%).In this cohort of apparently healthy men, adherence to healthy lifestyle factors is associated with a lower lifetime risk of heart failure.
Project description:BackgroundLifestyle factors including obesity and smoking are suggested to be correlated with increased risk of COVID-19 severe illness or related death. However, whether these relationships are causal is not well known; neither for the relationships between COVID-19 severe illness and other common lifestyle factors, such as physical activity and alcohol consumption.MethodsGenome-wide significant genetic variants associated with body mass index (BMI), lifetime smoking, physical activity and alcohol consumption identified by large-scale genome-wide association studies (GWAS) of up to 941,280 individuals were selected as instrumental variables. Summary statistics of the genetic variants on severe illness of COVID-19 were obtained from GWAS analyses of up to 6492 cases and 1,012,809 controls. Two-sample Mendelian randomisation analyses were conducted.ResultsBoth per-standard deviation (SD) increase in genetically predicted BMI and lifetime smoking were associated with about two-fold increased risks of severe respiratory COVID-19 and COVID-19 hospitalization (all P < 0.05). Per-SD increase in genetically predicted physical activity was associated with decreased risks of severe respiratory COVID-19 (odds ratio [OR] = 0.19; 95% confidence interval [CI], 0.05, 0.74; P = 0.02), but not with COVID-19 hospitalization (OR = 0.44; 95% CI 0.18, 1.07; P = 0.07). No evidence of association was found for genetically predicted alcohol consumption. Similar results were found across robust Mendelian randomisation methods.ConclusionsEvidence is found that BMI and smoking causally increase and physical activity might causally decrease the risk of COVID-19 severe illness. This study highlights the importance of maintaining a healthy lifestyle in protecting from COVID-19 severe illness and its public health value in fighting against COVID-19 pandemic.
Project description:ImportanceAn estimated 40% of dementia is potentially preventable by modifying 12 risk factors throughout the life course. However, robust evidence for most of these risk factors is lacking. Effective interventions should target risk factors in the causal pathway to dementia.ObjectiveTo comprehensively disentangle potentially causal aspects of modifiable risk factors for Alzheimer disease (AD) to inspire new drug targeting and improved prevention.Design, setting, and participantsThis genetic association study was conducted using 2-sample univariable and multivariable mendelian randomization. Independent genetic variants associated with modifiable risk factors were selected as instrumental variables from genomic consortia. Outcome data for AD were obtained from the European Alzheimer & Dementia Biobank (EADB), generated on August 31, 2021. Main analyses were conducted using the EADB clinically diagnosed end point data. All analyses were performed between April 12 and October 27, 2022.ExposuresGenetically determined modifiable risk factors.Main outcomes and measuresOdds ratios (ORs) and 95% CIs for AD were calculated per 1-unit change of genetically determined risk factors.ResultsThe EADB-diagnosed cohort included 39 106 participants with clinically diagnosed AD and 401 577 control participants without AD. The mean age ranged from 72 to 83 years for participants with AD and 51 to 80 years for control participants. Among participants with AD, 54% to 75% were female, and among control participants, 48% to 60% were female. Genetically determined high-density lipoprotein (HDL) cholesterol concentrations were associated with increased odds of AD (OR per 1-SD increase, 1.10 [95% CI, 1.05-1.16]). Genetically determined high systolic blood pressure was associated with increased risk of AD after adjusting for diastolic blood pressure (OR per 10-mm Hg increase, 1.22 [95% CI, 1.02-1.46]). In a second analysis to minimize bias due to sample overlap, the entire UK Biobank was excluded from the EADB consortium; odds for AD were similar for HDL cholesterol (OR per 1-SD unit increase, 1.08 [95% CI, 1.02-1.15]) and systolic blood pressure after adjusting for diastolic blood pressure (OR per 10-mm Hg increase, 1.23 [95% CI, 1.01-1.50]).Conclusions and relevanceThis genetic association study found novel genetic associations between high HDL cholesterol concentrations and high systolic blood pressure with higher risk of AD. These findings may inspire new drug targeting and improved prevention implementation.
Project description:Background and aimsLifestyle factors are well associated with risk of hepatocellular carcinoma (HCC). However, the impact of reducing adverse lifestyle behaviours on population-level burden of HCC is uncertain.MethodsWe conducted prospective analysis of the population-based multi-ethnic cohort (MEC) with linkage to cancer registries. The association of lifestyle factors (smoking, alcohol, diet quality assessed by alternate Mediterranean diet score, coffee drinking, physical activity and body mass index) with HCC incidence was examined using Cox regression. Population-attributable risk (PAR, %) for the overall, lean and overweight/obese populations was determined.ResultsA total of 753 incident cases of HCC were identified in 181,346 participants over median follow-up of 23.1 years. Lifestyle factors associated with elevated HCC risk included former/current smoking, heavy alcohol use, poor diet quality, lower coffee intake and obesity, but not physical activity. The lifestyle factor with highest PAR was lower coffee intake (21.3%; 95% CI: 8.9%-33.0%), followed by current smoking (15.1%; 11.1%-19.0%), obesity (14.5%; 9.2%-19.8%), heavy alcohol use (7.1%; 3.5%-10.6%) and lower diet quality (4.1%; 0.1%-8.1%). The combined PAR of all high-risk lifestyle factors was 51.9% (95% CI: 30.1%-68.6%). A higher combined PAR was observed among lean (65.2%, 26.8%-85.7%) compared to overweight/obese (37.4%, 11.7%-58.3%) participants. Adjusting for viral hepatitis status in a linked MEC-Medicare dataset resulted in similar PAR results.ConclusionsModifying lifestyle factors, particularly coffee intake, may have a substantial impact on HCC burden in diverse populations, with greater impact among lean adults. Diet and lifestyle counselling should be incorporated into HCC prevention strategies.