Body mass index and risk of suicide among men

BACKGROUND: Body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) has been linked to depression and the risk of suicide attempts and deaths in conflicting directions. METHODS: In a prospective cohort study of 46 755 men free of cancer enrolled in the Health Professionals Follow-up Study, participants reported their height, weight, diet, and physical activity on repeated occasions beginning in 1986 and were followed up until death or until February 2002. A subsample of 1829 men reported their mental health-related quality of life with the Mental Component Summary Scale of the 36-Item Short-Form Health Survey in 1998. RESULTS: A total of 131 men died from suicide during follow-up. A higher BMI was related to a graded decline in the suicide mortality rate, from 52 per 100 000 person-years among men with a BMI of less than 21 to 13 per 100 000 among men with a BMI of 30 or higher; the adjusted hazard ratio per 1-U BMI increment was 0.89 (95% confidence interval, 0.84-0.95; P<.001). The relationship was consistent when baseline or updated measures of BMI were used and with adjustment for medical illness, dietary factors, antidepressant use, physical activity, or social support. Height and physical activity were not strongly associated with risk. Analyses of mental health-related quality of life showed a similar positive relationship with BMI. CONCLUSIONS: Among men, risk of death from suicide is strongly inversely related to BMI, but not to height or to physical activity. Although obesity cannot be recommended on the basis of its detrimental effects, further research into the mechanisms of lower risk among overweight and obese men may provide insights into effective methods of suicide prevention.     

Body mass index in young men and the risk of subsequent knee and hip osteoarthritis

PURPOSE: Obesity in middle age is associated with an increased risk of osteoarthritis of the knees in later life. We sought to determine whether body mass index in young men was a risk factor for the subsequent development of osteoarthritis of the knee and hip. SUBJECTS AND METHODS: Body mass index was assessed in 1,180 male medical students at age 23 +/- 2 (mean +/- SD) years and at several times during follow-up. The incidence of knee and hip osteoarthritis was ascertained by self-report and corroborated with information on symptoms and radiographic findings. RESULTS: During a median follow-up of 36 years, 62 participants developed knee osteoarthritis and 27 developed hip osteoarthritis. The incidence of knee, but not hip, osteoarthritis was strongly associated with body mass index assessed at ages 20 to 29 years and 30 to 39 years (both P <0.001). For body mass index assessed at ages 20 to 29 years, the incidence of knee osteoarthritis at age 65 years was 12.8% among the heaviest subjects (range 24.7 to 37.6 kg/m2), threefold greater than the incidence of 4.0% in the leanest (15.6 to 22.8 kg/m2) category of body mass index (P = 0.0001). Thus, for a man who was 180 cm (5'11") tall, each 8 kg (18 lb) greater weight at ages 20 to 29 years was associated with an increased risk of subsequent knee osteoarthritis (relative risk = 1.7, 95% confidence interval 1.3 to 2.1), after adjustment for year of birth, physical activity, and knee injury. Body mass index at ages 20 to 29 years was more predictive of future osteoarthritis than at ages 30 to 39 or 40 to 49 years. CONCLUSION: Greater body mass index in young men ages 20 to 29 years is associated with an increased risk of subsequent knee, but not hip, osteoarthritis, suggesting that cumulative exposure to greater weight during young adult life is an important cause of osteoarthritis.     

Body mass index and the risk of COPD

BACKGROUND: Previous studies have documented the prognostic value of low body weight in patients with COPD and also in general populations. However, it is not clear whether low body weight is a risk factor for COPD or a consequence of established disease. STUDY OBJECTIVE: To determine whether asymptomatic subjects with low initial body mass were at a greater risk of having COPD develop during subsequent follow-up. DESIGN AND SUBJECTS: Observational retrospective study of 458 male and 192 female participants (age range, 40 to 73 years) in the Baltimore Longitudinal Study of Aging. At baseline, the participants did not have COPD. After mean follow-up periods of 10.2 years for the men and 6.4 years for the women, 40 men and 7 women received a diagnosis of COPD. METHODS: Cox proportional-hazards regression models were used to assess the relationship between COPD diagnosis and baseline body mass index (BMI) in men. RESULTS: The risk of COPD developing in men varied inversely with baseline BMI, even after adjusting for other risk factors, including cigarette smoking, age, FEV(1) percent predicted, abdominal obesity, and educational status. In men, the relative risk of COPD developing for the lowest BMI tertile relative to the highest tertile was 2.76 (95% confidence interval, 1.15 to 6.59). The small number of women who had COPD did not allow us to draw conclusions regarding BMI as a risk factor for COPD. CONCLUSION: After controlling for confounding variables, men with low BMI are at increased risk for getting COPD.     

Body mass index and the risk of asthma in adults

Asthma and obesity are both chronic conditions and their prevalences have risen in affluent societies. A positive association between asthma and being overweight or obese has been reported in children and women, but associations in men are less clearly described. The objective of this study was to explore the association between body mass index (BMI) and asthma in men and women of diverse ethnic and socioeconomic background living in New York State, USA. In this study, we analyzed cross-sectional data on 5524 subjects aged 18 years and older who were interviewed by telephone in the 1996 and 1997 New York State Behavioral Risk Factor Surveillance System. Asthma (doctor-diagnosed), and weight and height were self-reported. BMI (kg/m2) was used as a measure of adiposity. Weighted logistic regression analysis, with stratification by gender and age, was used to examine the relationship between asthma prevalence and BMI, adjusting for race/ethnicity, education, health insurance, time since last physical examination, physical activity and smoking status. The results showed that the prevalence of asthma was 4.6% (CI: 3.6-5.5%) among men and 8.1% (CI: 7.1-9.1%) among women. In women, the prevalence of asthma was significantly increased in those with a BMI 25 kg/m2 or higher (BMI 25-27.5: OR = 1.76, 95% CI: 1.06-2.94; BMI 27.5-29.9: OR = 2.45, 95% CI: 1.41-4.25; BMI > or = 30: OR = 2.67, 95% CI: 1.66-4.29) when compared to the reference category (BMI: 22-24.9 kg/m2). In men, the prevalence of asthma was increased in the lowest weight category, BMI < 22 kg/m2 (OR = 3.05, 95% CI: 1.37-6.78) and in the highest category, BMI > or = 30 kg/m2 (OR = 2.92, 95% CI: 1.39-6.14). This U-shaped association persisted when restricting the analysis to men who had never smoked and was more pronounced for those between 18 and 49 years of age. In conclusion, this cross-sectional study showed that men and women differ significantly in the association between BMI and asthma prevalence only with respect to the lowest weight category. While women had a monotonic association, men showed a U-shaped relationship, indicating that both extremes of weight are associated with a higher prevalence of asthma.     

Body mass index, waist circumference, and waist-hip ratio on the risk of total and type-specific stroke

BACKGROUND: Adiposity is an established risk factor for cardiovascular disease, but the relationship of adiposity with the risk of cerebrovascular disease is still to some extent unclear. METHODS: We prospectively investigated the association of different indicators of adiposity (body mass index [BMI] [calculated as weight in kilograms divided by height in meters squared], waist circumference, and waist-hip ratio) with total and type-specific stroke incidence among 49 996 Finnish participants who were aged 25 to 74 years and free of coronary heart disease and stroke at baseline. RESULTS: During a 19.5-year follow-up, 3228 people developed an incident stroke event (674 hemorrhagic and 2554 ischemic). Compared with normal-weight men (BMI, 18.5-24.9), the multivariate-adjusted (age, study year, smoking, physical activity, educational level, family history of stroke, and alcohol drinking) hazard ratios among lean (BMI, < 18.5), overweight (BMI, 25.0-29.9), and obese (BMI, > or = 30.0) men were 0.74 (95% confidence interval [CI], 0.18-2.96), 1.23 (95% CI, 1.10-1.37), and 1.59 (95% CI, 1.37-1.83) for total stroke, and 0.49 (95% CI, 0.07-3.50), 1.27 (95% CI, 1.12-1.44), and 1.70 (95% CI, 1.45-2.00) for ischemic stroke, respectively. Among women, the corresponding hazard ratios were 1.87 (95% CI, 1.12-3.14), 1.08 (95% CI, 0.95-1.22), and 1.30 (95% CI, 1.14-1.50) for total stroke, and 1.81 (95% CI, 0.97-3.41), 1.11 (95% CI, 0.96-1.28), and 1.41 (95% CI, 1.21-1.64) for ischemic stroke. Abdominal adiposity, defined as the highest quartile of waist circumference or waist-hip ratio, was associated with a greater risk of total and ischemic stroke in men but not in women. CONCLUSIONS: Body mass index was a risk factor for total and ischemic stroke in men and women. Abdominal adiposity was a risk factor for total and ischemic stroke only in men.     

Body mass index and mortality in men: evaluating the shape of the association

OBJECTIVE: Controversy regarding the relationship between body mass index (BMI) and mortality continues to exist. Most of the previous studies have not comprehensively accounted for major sources of bias. We examined the association between BMI and all-cause mortality according to pre-existing disease and smoking status in a large prospective cohort. METHODS: Participants were 99 253 male physicians in the Physicians' Health Study enrollment cohort (40-84 years) who provided self-reported information in 1982. We used Cox proportional hazards regression to examine the association between baseline BMI and mortality. RESULTS: A total of 5438 men died (median follow-up, 5.7 years). Although a U-shaped association between BMI and all-cause mortality was seen among all men, we found a linear relationship when accounting for potential sources of bias. In the optimal model excluding men who died within 2 years, and adjusting for age, smoking, alcohol consumption, physical activity, prior disease and interactions between BMI and prior disease, and between BMI and smoking, those with BMI <20.0 kg/m(2) had a relative risk (RR) of death of 0.88 (95% confidence interval (CI), 0.56-1.40), as compared to men with BMI 22.5-24.9 kg/m(2). By contrast, men with BMI 30.0-34.9 kg/m(2) had an RR of 1.45 (95% CI, 1.10-1.91) and those with BMI >or=35.0 kg/m(2) had an RR of 1.62 (95% CI, 1.12-2.35; P for linear trend, <0.001). According to WHO categories, men in the 'overweight' range (BMI 25.0-29.9 kg/m(2)) had an RR of 1.20 (95% CI, 1.05-1.38) as compared to men in the 'normal' range (BMI <25.0 kg/m(2)). CONCLUSIONS: In this large, prospective cohort, we found a consistent linear association between higher BMI and increased risk of mortality after accounting for several potential sources of bias, even among those within the 'overweight' range of BMI. Public health messages should emphasize the preponderance of evidence supporting the adverse health effects associated with higher body weight.     

Body mass index and risk of death in middle-aged men and women in Poland. Results of POL-MONICA cohort study

BACKGROUND: Overweight and obesity have been considered to be the causes of serious health consequences. So far, there have been no studies in Poland to analyse the relationship between Body Mass Index (BMI) and mortality. AIM: To determine the relationship between BMI and the mortality risk due to all causes and due to cardiovascular diseases (CVD) in the middle-aged population of Poland. METHODS: The study group consisted of men and women aged 35-64, residents of two districts of Warsaw (Praga Pó?noc and Praga Po?udnie) and the former Tarnobrzeg Voivodship who were selected at random for POL-MONICA Project cross-sectional studies in 1983-1994. Risk assessment of death due to all causes and due to CVD was performed using the Cox proportional hazards method. Persons with BMI of 22-23.9 were adopted as reference group. RESULTS: Sample size consisted of 5,281 men and 5,691 women. Prospective observation was carried out from 5 to 15 years, mean duration 10.7 years. Overall, the observation comprised 117,839 person-years. During the study, 914 men died (including 448 due to CVD) as well as 430 women (including 160 due to CVD). After adjusting for age, place of residence (Warsaw vs. the Tarnobrzeg Voivodship), risk factors (hypercholesterolemia, arterial hypertension and smoking) and self-assessment of health, increased risk of all cause death was found in men with BMI lower than 20 kg/m(2) (relative risk 2.27), with BMI of 32-34.9 kg/m(2) (relative risk 1.41), with BMI > or =35 kg/m(2) (relative risk 1.73), and in women whose BMI was lower than 20 kg/m(2) (relative risk 1.66). Increased risk of CVD death was found in men with BMI lower than 20 kg/m(2) (relative risk 1.97), with BMI of 32-34.9 kg/m(2) (relative risk 1.66), with BMI > or =35 kg/m(2) (relative risk 2.06), and in women with BMI > or =35.0 kg/m(2) (relative risk 2.02). CONCLUSIONS: The POL-MONICA study carried out in the middle-aged Polish population did not confirm a relationship between overweight (BMI from 25 to 29.9 kg/m(2)) and risk of death due to all causes or due to CVD.     

Body mass index of healthy men compared with healthy women in the United States

OBJECTIVE: To compare the distributions of body mass index (BMI) in relatively healthy nonsmoking men and women in the United States. DESIGN: Cross-sectional national survey data from the Third National Health and Nutrition Examination Survey (NHANES III). SUBJECTS:I n total, 11,404 nonsmoking men (n = 4894) and women (n = 6510), ages 20 years and above, drawn from a representative population sample. MEASUREMENTS: Increasingly stringent definitions of 'health' were applied, based on self-reported health, medical history, measurements of blood pressure, blood lipids, serum glucose, glycosylated hemoglobin, and behavioral factors including smoking and physical activity. Main outcome measures were mean and median BMI by health level, 5th and 95th percentiles of BMI, and the prevalence of overweight and obesity. RESULTS: For both men and women, the distribution of BMI became less skewed at better health levels. The range of BMI values that included 90% of healthy men and women was approximately 19.5-30 kg/m2 for men and 18-30 kg/m2 for women, with median values of approximately 24.5 kg/m2 for men and 21.5 kg/m2 for women. The prevalence of overweight declined sharply with increasing health level for women but varied little for men; the prevalence of obesity declined at higher health levels for both men and women. CONCLUSIONS: Only about 5% of healthy younger men or women would be classified as obese by BMI levels. However, the distribution of BMI differs between healthy men and healthy women. Relative to the distribution of BMI values for healthy men, the distribution of BMI values for healthy women is shifted to the left and is more skewed.     

Body mass index and hospitalization in the elderly

OBJECTIVES: To explore the association between body mass index (BMI) and hospital usage in the elderly. DESIGN: Retrospective cohort study. SETTING: Medicare Current Beneficiary Survey (1992-94). PARTICIPANTS: Eight thousand seven hundred fifty-four noninstitutionalized individuals aged 65 to 100 without cancer at baseline and with available data on height and weight. MEASUREMENTS: BMI categorized by quintiles and by the 1998 National Heart Lung and Blood Institute (NHLBI) BMI classification. Poisson regression was used for multivariate analyses relating BMI to number of hospitalizations, adjusting for sex, age, smoking status, and heart disease. RESULTS: During 20464 years of observation, 1199 individuals had 4096 hospitalizations and 34190 hospital days. Individuals in the lowest BMI quintile had a higher risk of hospitalization than those in the middle BMI quintile (RR=1.22; 95% confidence interval=1.1-1.4); stratified analyses by age revealed that this association remained for individuals aged 65 to 75. Using the NHLBI classification, underweight, overweight, mild obesity, and moderate to severe obesity were related to higher risk of hospitalizations than normal BMI in individuals aged 65 to 75. In individuals older than 75, underweight, overweight, and mild obesity were not related to a higher risk of hospitalizations. Moderate to severe obesity was related to a higher risk of hospitalization in individuals aged 75 to 89, which represented only 1.5% of the sample. CONCLUSION: BMI is not a predictor of hospitalization for most individuals aged 75 and older.     

A prospective study of body mass index and the risk of developing hypertension in men

BACKGROUND: Although obesity is known to increase the risk of hypertension, few studies have prospectively evaluated body mass index (BMI) across the range of normal weight and overweight as a primary risk factor. METHODS: In this prospective cohort, we evaluated the association between BMI and risk of incident hypertension. We studied 13,563 initially healthy, nonhypertensive men who participated in the Physicians' Health Study. We calculated BMI from self-reported weight and height and defined hypertension as self-reported systolic blood pressure (BP) > or = 140 mm Hg, diastolic BP > or = 90 mm Hg, or new antihypertensive medication use. RESULTS: After a median 14.5 years, 4920 participants developed hypertension. Higher baseline BMI, even within the "normal" range, was consistently associated with increased risk of hypertension. Compared to participants in the lowest BMI quintile (<22.4 kg/m(2)), the relative risks (95% confidence interval) of developing hypertension for men with a BMI of 22.4 to 23.6, 23.7 to 24.7, 24.8 to 26.4, and >26.4 kg/m(2) were 1.20 (1.09-1.32), 1.31 (1.19-1.44), 1.56 (1.42-1.72), and 1.85 (1.69-2.03), respectively (P for trend, <.0001). Further adjustment for diabetes, high cholesterol, and baseline BP did not substantially alter these results. We found similar associations using other BMI categories and after excluding men with smoking history, those who developed hypertension in the first 2 years, and those with diabetes, obesity, or high cholesterol at baseline. CONCLUSIONS: In this large cohort, we found a strong gradient between higher BMI and increased risk of hypertension, even among men within the "normal" and mildly "overweight" BMI range. Approaches to reduce the risk of developing hypertension may include prevention of overweight and obesity.