Weight change and all-cause, cancer and cardiovascular disease mortality in Japanese men and women: the Japan Public Health Center-Based Prospective Study.

BACKGROUND: It is unclear whether weight change during adulthood influences subsequent mortality in Asian populations, who have a relatively lean body mass.

OBJECTIVE: To assess the relation of weight change over 5 years to all-cause, cancer and cardiovascular disease mortality among Japanese men and women.

DESIGN: Subjects were 36 220 men and 44 091 women aged between 45 and 75 years without a history of serious disease at baseline. Weight change was calculated as the difference of body weight between two surveys with a 5-year interval.

RESULTS: During 699 963 person-years of follow-up, we identified 4232 deaths of all-cause, 1872 cancer deaths and 1021 cardiovascular deaths. The relation between weight change and all-cause mortality was reverse J-shaped. Multivariate hazard ratios (95% confidence interval) for weight loss of 5 kg or more versus weight change of less than 2.5 kg were 1.62 (1.45-1.81) in men and 1.76 (1.51-2.05) in women, whereas those for weight gain of 5 kg or more were 1.40 (1.22-1.59) in men and 1.25 (1.02-1.54) in women. These associations remained statistically significant even after the exclusion of deaths in the first 3 years of follow-up. The weight change-mortality association was pronounced in underweight persons or in nonsmoking men. The risk of cancer mortality increased in both men and women who lost weight by 5 kg or more. With regard to cardiovascular disease, mortality risk tended to increase with weight loss both in men and women, whereas its increase with weight gain was observed only in women.

CONCLUSIONS: A large weight change, both loss and gain, was associated with an increased risk of mortality. Weight loss and gain may be predictors of early death in apparently healthy adult Japanese.