Body Habitus Across the Lifespan and Risk of Pituitary Adenoma

Abstract Context No studies have examined the association between body habitus and incidence of pituitary adenoma. Objective To determine if body mass index (BMI), waist circumference, body somatotype, or height are associated with risk of pituitary adenoma. Design Pooled analysis of 3 prospective cohort studies. Setting Population-based study. Participants Participants of the Nurses’ Health Study (NHS), Nurses’ Health Study II (NHSII), and the Health Professionals Follow-Up Study (HPFS), totaling 284 946 American health professionals. Exposures BMI, waist circumference, body somatotype, and height. Outcome Measures Self-reported incident pituitary adenoma. Multivariable (MV)-adjusted hazard ratios (HRs) of pituitary adenoma were estimated using Cox proportional hazards models. Results During 7 350 156 person-years of follow-up, 387 incident pituitary adenomas were reported. Comparing BMI of ≥30 to <25 kg/m2, higher adult BMI was associated with higher risk of pituitary adenoma (MV HR = 1.74; 95% CI, 1.33-2.28), as was higher maximum adult BMI (MV HR = 1.76; 95% CI, 1.34-2.30), higher waist circumference (MV HR = 1.06; 95% CI, 1.04-1.09 per inch), and higher BMI during early adulthood (at age 18 to 21, MV HR = 2.65; 95% CI, 1.56-4.49). Taller adult height was associated with pituitary adenoma (MV HR = 1.05; 95% CI, 1.01-1.09 per inch). Overall findings were similar in women and men, although power was limited in men (n = 62 cases). Sensitivity analyses demonstrated that the association between adult BMI and pituitary adenoma extended to at least 14 years prior to diagnosis and that the results were not affected when analyses were restricted to participants with similar healthcare utilization. Conclusion Higher BMI and waist circumference, from early adulthood to the time of diagnosis, were associated with higher risk of pituitary adenoma.

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Abstract P270: Body Size Throughout the Life Course and Risk of Venous Thromboembolism

Circulation ◽

10.1161/circ.137.suppl_1.p270 ◽

2018 ◽

Vol 137 (suppl_1) ◽

Author(s):

Kaitlin A Hagan ◽

Laura B Harrington ◽

Jihye Kim ◽

Francine Grodstein ◽

Christopher Kabrhel

Keyword(s):

Body Size ◽

Venous Thromboembolism ◽

Waist Circumference ◽

Early Life ◽

Proportional Hazards ◽

Cox Proportional Hazards ◽

Health Study ◽

Hip Circumference ◽

Adult Body Mass

Introduction: Adult body mass index (BMI) is strongly associated with venous thromboembolism (VTE), however whether earlier-life adiposity or other measures of adult adiposity are associated with VTE risk remains unknown. Hypothesis: Since BMI is a strong risk factor for incident VTE, we hypothesized that early life body size as well as other measures of adult adiposity may also be positively associated with VTE risk. Methods: We evaluated associations of childhood somatotype, BMI at age 18, change in BMI since age 18, and measures of waist and hip circumference with incident VTE among 47,415 women age 40-67 years at baseline from the Nurses’ Health Study (NHS), 47,539 women age 29-48 years from the Nurses’ Health Study II (NHS II), and 32,707 men age 39-76 years from the Health Professionals Follow-Up Study (HPFS) without a prior VTE. We calculated multivariable-adjusted hazard ratios (HR) of VTE using Cox proportional hazards models. Results: Over ≥25 years of follow-up, there were 1,191 incident VTE cases in NHS, 763 cases in NHS II, and 1,350 cases in HPFS. Adult BMI was strongly associated with VTE in all three cohorts (HRs comparing ≥35 kg/m 2 vs. <22.5 kg/m 2 : NHS: 3.03 [95% CI: 2.58, 3.55], NHS II: 3.88 [95% CI: 3.36, 4.48], HPFS: 2.49 [95% CI: 1.83, 3.29]; all P trend< 0.01). Waist circumference, hip circumference, and height were associated with greater VTE risk, even after adjusting for adult BMI (all P trend< 0.01) (Table). Somatotype at ages 5 and 10, BMI at age 18, and change in BMI since age 18 were not significantly associated with VTE risk, after accounting for adult BMI. Conclusions: Adult BMI, waist circumference, hip circumference, and height were independently, positively associated with incident VTE risk. Early life body size was not significantly associated with VTE risk after accounting for adult BMI, indicating that BMI and adiposity are likely more important acutely that cumulatively over time in the etiology of VTE. Clinically, encouraging weight loss in adults

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Association of oral contraceptives and tubal ligation with risk of early natural menopause

Human Reproduction ◽

10.1093/humrep/deab054 ◽

2021 ◽

Author(s):

C R Langton ◽

B W Whitcomb ◽

A C Purdue-Smithe ◽

L L Sievert ◽

S E Hankinson ◽

...

Keyword(s):

Oral Contraceptives ◽

Proportional Hazards ◽

Reproductive Factors ◽

Cox Proportional Hazards ◽

Tubal Ligation ◽

Health Study ◽

Early Menopause ◽

Natural Menopause ◽

Increased Risk

Abstract STUDY QUESTION What is the association of oral contraceptives (OCs) and tubal ligation (TL) with early natural menopause? SUMMARY ANSWER We did not observe an association of OC use with risk of early natural menopause; however, TL was associated with a modestly higher risk. WHAT IS KNOWN ALREADY OCs manipulate hormone levels, prevent ovulation, and may modify the rate of follicular atresia, while TL may disrupt the blood supply to the ovaries. These mechanisms may be associated with risk of early menopause, a condition associated with increased risk of cardiovascular disease and other adverse health outcomes. STUDY DESIGN, SIZE, DURATION We examined the association of OC use and TL with natural menopause before the age of 45 years in a population-based study within the prospective Nurses’ Health Study II (NHSII) cohort. Participants were followed from 1989 to 2017 and response rates were 85-90% for each cycle. PARTICIPANTS/MATERIALS, SETTING, METHODS Participants included 106 633 NHSII members who were premenopausal and aged 25-42 years at baseline. Use, duration and type of OC, and TL were measured at baseline and every 2 years. Menopause status and age were assessed every 2 years. Follow-up continued until early menopause, age 45 years, hysterectomy, oophorectomy, death, cancer diagnosis, or loss to follow-up. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% CIs adjusted for lifestyle, dietary, and reproductive factors. MAIN RESULTS AND THE ROLE OF CHANCE Over 1.6 million person-years, 2579 members of the analytic cohort experienced early natural menopause. In multivariable models, the duration, timing, and type of OC use were not associated with risk of early menopause. For example, compared with women who never used OCs, those reporting 120+ months of OC use had an HR for early menopause of 1.01 (95% CI, 0.87-1.17; P for trend=0.71). TL was associated with increased risk of early menopause (HR = 1.17, 95% CI, 1.06-1.28). LIMITATIONS, REASONS FOR CAUTION Our study population is homogenous with respect to race and ethnicity. Additional evaluation of these relations in more diverse populations is important. WIDER IMPLICATIONS OF THE FINDINGS To our knowledge, this is the largest study examining the association of OC use and TL with early natural menopause to date. While TL was associated with a modest higher risk of early menopause, our findings do not support any material hazard or benefit for the use of OCs. STUDY FUNDING/COMPETING INTEREST(S) The study was sponsored by UO1CA176726 and R01HD078517 from the National Institutes of Health and Department of Health and Human Services. The work was supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The authors have no competing interests to report. TRIAL REGISTRATION NUMBER N/A

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Long-term efficacy of mycophenolate mofetil in myelin oligodendrocyte glycoprotein antibody-associated disorders

Neurology Neuroimmunology & Neuroinflammation ◽

10.1212/nxi.0000000000000705 ◽

2020 ◽

Vol 7 (3) ◽

pp. e705 ◽

Cited By ~ 9

Author(s):

Shengde Li ◽

Haitao Ren ◽

Yan Xu ◽

Tao Xu ◽

Yao Zhang ◽

...

Keyword(s):

Mycophenolate Mofetil ◽

Proportional Hazards ◽

Myelin Oligodendrocyte Glycoprotein ◽

Cox Proportional Hazards ◽

Sensitivity Analyses ◽

College Hospital ◽

Relapse Risk ◽

Medical College ◽

Cox Proportional Hazards Models

ObjectiveTo investigate whether the use of mycophenolate mofetil (MMF) could reduce the relapse risk in patients with myelin oligodendrocyte glycoprotein (MOG)-immunoglobulin G (IgG)-associated disorders (MOGADs).MethodsThis prospective observational cohort study included patients with MOGAD at Peking Union Medical College Hospital between January 1, 2017, and April 30, 2019. The patients were divided into 2 groups: those with (MMF+) or without (MMF−) MMF therapy. The primary outcome was relapse at follow-up. We used Cox proportional hazards models to calculate hazard ratios (HRs) for relapse.ResultsSeventy-nine patients were included in our MOG cohort. Fifty (63.3%) were adults at index date, and 47 (59.5%) were women. Fifty-four (68.4%) were in the MMF+ group, and 25 (31.6%) were in the MMF− group. Clinical and demographic factors, MOG-IgG titer, and follow-up time (median, 472.5 days for MMF+, 261.0 days for MMF−) were comparable between the groups. Relapse rates were 7.4% (4/54) in the MMF+ group and 44.0% (11/25) in the MMF− group. Of all potential confounders, only the use of MMF was associated with reduced risk of relapse. The HR for relapse among patients in the MMF+ group was 0.14 (95% CI, 0.05–0.45) and was 0.08 (95% CI, 0.02–0.28) in a model adjusted for age, sex, disease course, and MOG-IgG titer. MMF therapy also remained associated with a reduced relapse risk in sensitivity analyses. Only one patient (1.9%) discontinued MMF therapy because of adverse effect.ConclusionsThese findings provide a clinical evidence that MMF immunosuppression therapy may prevent relapse in patients with MOGAD.Classification of evidenceThis study provides class IV evidence that for patients with MOGAD, MMF reduces relapse risk.

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Meat intake and risk of hepatocellular carcinoma in two large US prospective cohorts of women and men

International Journal of Epidemiology ◽

10.1093/ije/dyz146 ◽

2019 ◽

Cited By ~ 5

Author(s):

Yanan Ma ◽

Wanshui Yang ◽

Tricia Li ◽

Yue Liu ◽

Tracey G Simon ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Proportional Hazards ◽

Red Meat ◽

Cox Proportional Hazards ◽

Fish Intake ◽

Health Study ◽

Meat Intake ◽

Red Meats ◽

Processed Red Meat

Abstract Background Epidemiological evidence on the associations between meat intake and risk of hepatocellular carcinoma (HCC) was limited and inconsistent. Methods We prospectively examined the association between consumption of meats and meat mutagens with HCC risk using data from the Nurses’ Health Study and the Health Professionals Follow-up Study. Cox proportional-hazards regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) after adjusting for known liver-cancer risk factors. Results During up to 32 years of follow-up, we documented 163 incident HCC cases. The HRs of HCC for the highest vs the lowest tertile intake levels were 1.84 (95% CI: 1.16–2.92, Ptrend = 0.04) for processed red meats and 0.61 (95% CI: 0.40–0.91, Ptrend = 0.02) for total white meats. There was a null association between unprocessed red meats and HCC risk (HR = 1.06, 95% CI: 0.68–1.63, Ptrend = 0.85). We found both poultry (HR = 0.60, 95% CI: 0.40–0.90, Ptrend = 0.01) and fish (HR = 0.70, 95% CI: 0.47–1.05, Ptrend = 0.10) were inversely associated with HCC risk. The HR for HCC risk was 0.79 (95% CI: 0.61–1.02) when 1 standard deviation of processed red meats was substituted with an equivalent amount of poultry or fish intake. We also found a suggestive positive association of intake of meat-derived mutagenicity or heterocyclic amines with risk of HCC. Conclusions Processed red meat intake might be associated with higher, whereas poultry or possibly fish intake might be associated with lower, risk of HCC. Replacing processed red meat with poultry or fish might be associated with reduced HCC risk.

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Dietary selenium intake and mortality in two population-based cohort studies of 133 957 Chinese men and women

Public Health Nutrition ◽

10.1017/s1368980016001130 ◽

2016 ◽

Vol 19 (16) ◽

pp. 2991-2998 ◽

Cited By ~ 7

Author(s):

Jiang-Wei Sun ◽

Xiao-Ou Shu ◽

Hong-Lan Li ◽

Wei Zhang ◽

Jing Gao ◽

...

Keyword(s):

Cancer Mortality ◽

Proportional Hazards ◽

Population Based ◽

Cox Proportional Hazards ◽

Sensitivity Analyses ◽

Health Study ◽

Chinese Populations ◽

Urban City ◽

Cox Proportional Hazards Models ◽

Hazard Ratios

AbstractObjectiveTo investigate the potential influence of dietary Se intake on mortality among Chinese populations.DesignWe prospectively evaluated all-cause, CVD and cancer mortality risks associated with dietary Se intake in participants of the Shanghai Women’s Health Study (SWHS) and the Shanghai Men’s Health study (SMHS). Dietary Se intake was assessed by validated FFQ during in-person interviews. Cox proportional hazards models were used to calculate hazard ratios (HR) and 95 % CI.SettingUrban city in China.SubjectsChinese adults (n 133 957).ResultsDuring an average follow-up of 13·90 years in the SWHS and 8·37 years in the SMHS, 5749 women and 4217 men died. The mean estimated dietary Se intake was 45·48 μg/d for women and 51·34 μg/d for men, respectively. Dietary Se intake was inversely associated with all-cause mortality and CVD mortality in both women and men, with respective HR for the highest compared with the lowest quintile being 0·79 (95 % CI 0·71, 0·88; Ptrend<0·0001) and 0·80 (95 % CI 0·66, 0·98; Ptrend=0·0268) for women, and 0·79 (95 % CI 0·70, 0·89; Ptrend=0·0001) and 0·66 (95 % CI 0·54, 0·82; Ptrend=0·0002) for men. No significant associations were observed for cancer mortality in both women and men. Results were similar in subgroup and sensitivity analyses.ConclusionsDietary Se intake was inversely associated with all-cause and cardiovascular mortality in both sexes, but not cancer mortality.

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Prediabetes, Diabetes, and the Risk of All-Cause and Cause-Specific Mortality in a Japanese Working Population: Japan Epidemiology Collaboration on Occupational Health Study

10.2337/figshare.13483515 ◽

2021 ◽

Author(s):

Zobida Islam ◽

Shamima Akter ◽

Yosuke Inoue ◽

Huan Hu ◽

Keisuke Kuwahara ◽

...

Keyword(s):

Proportional Hazards ◽

Cox Proportional Hazards ◽

World Health ◽

Health Study ◽

Expert Committee ◽

Risk Of Mortality ◽

Japanese Workers ◽

Increased Risk ◽

Health Organization

Objective: Prediabetes has been suggested to increase mortality risk; however, the definitions of prediabetes that can predict mortality remain elusive. We prospectively investigated the association of multiple definitions of prediabetes with the risk of mortality from all-causes, cardiovascular disease (CVD), and cancer in Japanese workers. Research design and methods: The study included 62,785 workers who underwent a health checkup in 2010 or 2011 and were followed up for mortality from 2012 to March 2019. <a>Prediabetes was defined according to fasting plasma glucose (FPG) or glycated hemoglobin (HbA1c) level or a combination of both using the American Diabetes Association (ADA) or World Health Organization (WHO)/International Expert Committee (IEC) criteria. </a>The Cox proportional hazards regression model was used to investigate the associations. Results: Over a 7-year follow-up, 229 deaths were documented. <a>Compared with normoglycemia, prediabetes defined according to ADA criteria was associated with a higher risk of all-cause (hazard ratio [HR] 1.53; 95% confidence interval [CI] 1.12–2.09) and cancer (HR 2.37; 95% CI 1.45–3.89) mortality but not with CVD mortality. </a>The results were materially unchanged when prediabetes was defined according to ADA FPG, ADA HbA1c, WHO FPG, or combined WHO/IEC criteria. Diabetes was associated with the risk of all-cause, CVD, and cancer mortality. Conclusion: In a cohort of Japanese workers, FPG- and HbA1c-defined prediabetes according to ADA or WHO/IEC was each associated with a significantly increased risk of mortality from all-causes and cancer but not CVD.

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Changes in Plant-Based Diet Quality and Total and Cause-Specific Mortality

Circulation ◽

10.1161/circulationaha.119.041014 ◽

2019 ◽

Vol 140 (12) ◽

pp. 979-991 ◽

Cited By ~ 11

Author(s):

Megu Y. Baden ◽

Gang Liu ◽

Ambika Satija ◽

Yanping Li ◽

Qi Sun ◽

...

Keyword(s):

Diet Quality ◽

Lower Risk ◽

Proportional Hazards ◽

Total Mortality ◽

Cox Proportional Hazards ◽

Environmental Benefits ◽

Health Study ◽

Specific Mortality ◽

Cvd Mortality

Background: Plant-based diets have been associated with lower risk of type 2 diabetes mellitus and cardiovascular disease (CVD) and are recommended for both health and environmental benefits. However, the association between changes in plant-based diet quality and mortality remains unclear. Methods: We investigated the associations between 12-year changes (from 1986 to 1998) in plant-based diet quality assessed by 3 plant-based diet indices (score range, 18–90)—an overall plant-based diet index (PDI), a healthful PDI, and an unhealthful PDI—and subsequent total and cause-specific mortality (1998–2014). Participants were 49 407 women in the Nurses’ Health Study (NHS) and 25 907 men in the Health Professionals Follow-Up Study (HPFS) who were free from CVD and cancer in 1998. Multivariable-adjusted Cox proportional-hazards models were used to estimate hazard ratios (HRs) and 95% CIs. Results: We documented 10 686 deaths including 2046 CVD deaths and 3091 cancer deaths in the NHS over 725 316 person-years of follow-up and 6490 deaths including 1872 CVD deaths and 1772 cancer deaths in the HPFS over 371 322 person-years of follow-up. Compared with participants whose indices remained stable, among those with the greatest increases in diet scores (highest quintile), the pooled multivariable-adjusted HRs for total mortality were 0.95 (95% CI, 0.90–1.00) for PDI, 0.90 (95% CI, 0.85–0.95) for healthful PDI, and 1.12 (95% CI, 1.07–1.18) for unhealthful PDI. Among participants with the greatest decrease (lowest quintile), the multivariable-adjusted HRs were 1.09 (95% CI, 1.04–1.15) for PDI, 1.10 (95% CI, 1.05–1.15) for healthful PDI, and 0.93 (95% CI, 0.88–0.98) for unhealthful PDI. For CVD mortality, the risk associated with a 10-point increase in each PDI was 7% lower (95% CI, 1–12%) for PDI, 9% lower (95% CI, 4–14%) for healthful PDI, and 8% higher (95% CI, 2–14%) for unhealthful PDI. There were no consistent associations between changes in plant-based diet indices and cancer mortality. Conclusions: Improving plant-based diet quality over a 12-year period was associated with a lower risk of total and CVD mortality, whereas increased consumption of an unhealthful plant-based diet was associated with a higher risk of total and CVD mortality.

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Abstract P288: Exposure To Psychological And Physical Challenges Immediately Prior To Myocardial Infarction And Increased 10-year Mortality

Circulation ◽

10.1161/circ.129.suppl_1.p288 ◽

2014 ◽

Vol 129 (suppl_1) ◽

Author(s):

Loes Smeijers ◽

Elizabeth Mostofsky ◽

Willem J Kop ◽

Murray A Mittelman

Keyword(s):

Physical Activity ◽

Myocardial Infarction ◽

Mortality Rate ◽

Proportional Hazards ◽

Coffee Consumption ◽

Cox Proportional Hazards ◽

Sensitivity Analyses ◽

Risk Indicator ◽

All Cause Mortality

Objective: To examine the association between exposure to psychological (anger, anxiety) and physical (high activity levels, coffee consumption) challenge immediately prior to myocardial infarction (MI) as risk indicator of mortality at 10-year follow-up. Methods: Participants of the Determinants of Myocardial Infarction Onset Study (N=2176, mean age 60.1±12.5 yrs, 29.2% women) were interviewed to assess exposure to several potential triggers immediately prior to MI, including anger, anxiety, physical activity and coffee. All-cause mortality was assessed using the National Death Index for 10 years follow-up. We constructed Cox proportional hazards models with 95% confidence intervals to examine the relationship between exposure to these potential triggers in the 2 hours prior to MI onset and the rate of all-cause mortality, adjusting for demographic and clinical characteristics. Results: Exposure to anger, anxiety, physical activity or coffee consumption prior to MI was associated with a 30% higher mortality rate over 10 years (HR=1.30, 95%CI=1.06-1.59, p =0.011) compared to patients who were not exposed to any of these potential triggers. This association was stronger for the first 3 years of follow-up (HR=1.59, 95%CI=1.16-2.19, p =0.004) and weaker for years 3 to 10 (HR=1.14, 95%CI=0.88-1.48, p =0.32). In separate analyses for each exposure, there was a higher mortality rate associated with anxiety (HR=1.44, 95%CI=1.09-1.91, p =0.010) and a suggestion of a higher rate for anger (HR=1.33, 95%CI=0.97-1.81, p =0.075), but no association for physical activity or coffee consumption. Sensitivity analyses showed stronger associations for women than men, and patients aged 65 and older compared to younger patients. Discussion: MI following episodes of anger, anxiety, physical activity or coffee consumption is associated with higher all-cause mortality in the following 10 years. This association was strongest for anxiety and slightly lower for anger but there was no evidence of a higher mortality rate among MI patients reporting physical activity or coffee consumption immediately prior to MI.

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Extended Mortality Follow-up of a Cohort of 25,460 Workers Exposed to Acrylonitrile

American Journal of Epidemiology ◽

10.1093/aje/kwz086 ◽

2019 ◽

Vol 188 (8) ◽

pp. 1484-1492 ◽

Cited By ~ 2

Author(s):

Stella Koutros ◽

Jay H Lubin ◽

Barry I Graubard ◽

Aaron Blair ◽

Patricia A Stewart ◽

...

Keyword(s):

Bladder Cancer ◽

Proportional Hazards ◽

Cox Regression ◽

The United States ◽

Cox Proportional Hazards ◽

Sensitivity Analyses ◽

Increased Risk ◽

Total Cancer ◽

Standardized Mortality Ratios

Abstract We extended the mortality follow-up of a cohort of 25,460 workers employed at 8 acrylonitrile (AN)-producing facilities in the United States by 21 years. Using 8,124 deaths and 1,023,922 person-years of follow-up, we evaluated the relationship between occupational AN exposure and death. Standardized mortality ratios (SMRs) based on deaths through December 31, 2011, were calculated. Work histories and monitoring data were used to develop quantitative estimates of AN exposure. Hazard ratios were estimated by Cox proportional hazards regression. All-cause mortality and death from total cancer were less than expected compared with the US population. We observed an excess of death due to mesothelioma (SMR = 2.24, 95% confidence interval (CI): 1.39, 3.42); no other SMRs were elevated overall. Cox regression analyses revealed an elevated risk of lung and bronchial cancer (n = 808 deaths; for >12.1 ppm-year vs. unexposed, hazard ratio (HR) = 1.43, 95% CI: 1.13, 1.81; P for trend = 0.05), lagged 10 years, that was robust in sensitivity analyses adjusted for smoking and co-exposures including asbestos. Death resulting from bladder cancer (for >2.56 ppm vs. unexposed, lagged 10-year HR = 2.96, 95% CI: 1.38, 6.34; P for trend = 0.02) and pneumonitis (for >3.12 ppm-year vs. unexposed, HR = 4.73, 95% CI: 1.42, 15.76; P for trend = 0.007) was also associated with AN exposure. We provide additional evidence of an association between AN exposure and lung cancer, as well as possible increased risk for death due to bladder cancer and pneumonitis.

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Independent effects of waist circumference and physical activity on all-cause mortality in Canadian women

Applied Physiology Nutrition and Metabolism ◽

10.1139/h05-038 ◽

2006 ◽

Vol 31 (3) ◽

pp. 271-276 ◽

Cited By ~ 24

Author(s):

Peter T Katzmarzyk ◽

Cora L Craig

Keyword(s):

Physical Activity ◽

Cohort Study ◽

Waist Circumference ◽

Physical Inactivity ◽

Proportional Hazards ◽

Leisure Time Physical Activity ◽

Smoking Status ◽

Cox Proportional Hazards ◽

Independent Effects

The purpose of this study was to determine the independent effects of waist circumference (WC) and physical inactivity on the risk of mortality in women. This prospective cohort study included 5421 female participants 20-69 years of age in the 1981 Canada Fitness Survey. WC was measured with an anthropometric tape and leisure-time physical activity levels over the previous 12 months were assessed with a questionnaire. Mortality surveillance was conducted by data linkage with the Canadian Mortality Database through 31 December, 1993. The hazard ratios (HR) of mortality were estimated using Cox proportional hazards regression with age, smoking status, and alcohol con sumption included as covariates in all models. A total of 225 deaths occurred over an average of 12.4 years of follow up (67 500 person-years of follow up). Physical activity (HR = 0.78; 95% C.I.: 0.64-0.95) and WC (HR = 1.17; 95% C.I.: 1.05-1.31) were associated with mortality when included in separate regression models. When included in the same model, both physical activity (HR = 0.79; 95% CI: 0.65-0.96) and WC (HR = 1.16; 95% C.I.: 1.04-1.30) remained independent significant predictors of mortality. In conclusion, physical inactivity and high WC have significant independent risks of premature mortality among women.Key words: death, obesity, cohort study, Canada Fitness Survey.

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