Similarities in cardiometabolic risk factors among random male-female pairs: A large observational study in Japan

Abstract Background: Spousal similarities exist in several cardiometabolic risk factors and have been noted in previous studies that used public biobank information from two countries. This study aimed to challenge the influence of genetic factors and determine the influence of the environment on cardiometabolic risk factors by using random male-female pairs rather than spouse pairs.Methods: This cross-sectional study included 5391 spouse pairs from Japan; data were obtained from a large biobank study. For pairings, women of the same age were randomly shuffled to create new male-female pairs of the same age as the original spouse pairs. Similarities in cardiometabolic risk factors between the random male-female pairs were analysed using the Pearson's correlation or age-adjusted logistic regression analyses.Results: The mean ages of the men and women were 63.2 and 60.4 years, respectively. No significant similarities were noted in cardiometabolic risk factors, including the continuous risk factors (anthropometric traits, blood pressure, glycated haemoglobin level, and lipid traits); lifestyle habits (smoking, drinking, and physical activity); or diseases (hypertension, type 2 diabetes mellitus, and metabolic syndrome) between the random male-female pairs. The age-adjusted correlation coefficients ranged from -0.002 for triglycerides to 0.071 for total cholesterol. The age-adjusted odds ratio (95% confidence interval) for current drinkers was 0.94 (0.81−1.09); ever smokers, 0.99 (0.83−1.18); hypertension, 1.07 (0.93−1.23); and type 2 diabetes mellitus, 1.08 (0.77−1.50). Conclusion: In this study, no similarities in cardiometabolic risk factors were noted among the random male-female pairs. As spouse pairs may share environmental factors, intervention strategies targeting lifestyle habits and prevent lifestyle-related diseases may be effective.