Married couples might be an appropriate target for obesity prevention interventions. In the present study, we aimed to evaluate whether an individual's risk of obesity is associated with spousal risk of obesity and whether an individual's change in body mass index (BMI; weight in kilograms divided by height in meters squared) is associated with spousal BMI change. We analyzed data from 3,889 spouse pairs in the Atherosclerosis Risk in Communities Study cohort who were sampled at ages 45-65 years from 1986 to 1989 and followed for up to 25 years. We estimated hazard ratios for incident obesity by whether spouses remained nonobese, became obese, remained obese, or became nonobese. We estimated the association of participants' BMI changes with concurrent spousal BMI changes using linear mixed models. Analyses were stratified by sex. At baseline, 22.6% of men and 24.7% of women were obese. Nonobese participants whose spouses became obese were more likely to become obese themselves (for men, hazard ratio = 1.78, 95% confidence interval: 1.30, 2.43; for women, hazard ratio = 1.89, 95% confidence interval: 1.39, 2.57). With each 1-unit increase in spousal BMI change, women's BMI change increased by 0.15 (95% confidence interval: 0.13, 0.18) and men's BMI change increased by 0.10 (95% confidence interval: 0.09, 0.12). Having a spouse become obese nearly doubles one's risk of becoming obese. Future research should consider exploring the efficacy of obesity prevention interventions in couples.
Bibliographical noteFunding Information:
Author affiliations: Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins University, Baltimore, Maryland (Laura K. Cobb, Mara A. McAdams- DeMarco, Kimberly A.Gudzune, Mark Woodward, Elizabeth Selvin, Josef Coresh); Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland (Laura K. Cobb, Mara A. McAdams- DeMarco, Cheryl A. M. Anderson, Mark Woodward, Elizabeth Selvin, Josef Coresh); Division of General Internal Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland (Kimberly A. Gudzune); Department of Family and Preventive Medicine, School of Medicine, University of California, San Diego, San Diego, California (Cheryl A. M. Anderson); Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, Minnesota (Ellen Demerath); The George Institute for Global Health, University of Sydney, Sydney, Australia (Mark Woodward); and Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom (Mark Woodward). The Atherosclerosis Risk in Communities Study is carried out as a collaborative study supported by National Heart, Lung, and Blood Institute contracts HHSN268201100005C, HHSN268201100006C, HHSN268201100007C, HHSN268201100008C, HHSN268201100009C, HHSN268201100010C, HHSN268201100011C, and HHSN268201100012C. L.K.C. was supported in part by the National Heart, Lung, and Blood Institute Cardiovascular Epidemiology Training Grant (T32HL007024) and the National Institute of Diabetes and Digestive Kidney Diseases Diabetes and Endocrinology Training Grant (2T32DK062707-11A1). K.A.G. is supported by a career development award from NHLBI (K23HL116601).M.A.M.-D. is supported by a career development award from the National Institute on Aging (K01AG043501). We thank the staff of the Atherosclerosis Risk in Communities Study for their important contributions.
- cohort study