Objective: To investigate the association between weight change in older adults and mortality in a multiethnic population.
Methods: We performed a prospective analysis using data on weight change between the baseline (1993-1996) and the 10-year follow-up (2003-2007) surveys in relation to subsequent mortality among 63 040 participants in the Multiethnic Cohort Study in Hawaii and California. The participants were African American, Native Hawaiian, Japanese American, Latino and white, aged 45-75 years at baseline, and did not report heart disease or cancer at either survey.
Results: During an average of 7.3 years of follow-up after the 10-year survey, 6623 deaths were identified. Compared with individuals whose weight remained stable (±2.5 kg), those who lost weight and those with the highest weight gain (>10 kg) were at increased risk of all-cause mortality, with the risks greater for the weight loss (hazard ratios (HR): 2.86; 95% confidence interval (95% CI): 2.62-3.11 for >10 kg) than the weight-gain group (HR: 1.25; 95% CI: 1.11-1.41 for >10 kg), thus resulting in a reverse J-shaped curve. Japanese Americans and Latinos had stronger associations of weight loss >10 kg with mortality than did African Americans, Native Hawaiians and whites. The increase in risk with weight gain >10 kg was greater for older (⩾55 years at baseline) than younger individuals, whereas the increase in mortality associated with weight loss was greater for the normal weight (<25 kg m-2 at baseline) participants and never smokers, compared with overweight/obese persons and current smokers, respectively.
Conclusions: Our findings confirm the association between weight change and a higher mortality in a healthy, multiethnic population, with higher risks for weight loss than weight gain. On the basis of these observations, public health recommendation should focus on the prevention of weight loss, as well as weight stability within the non-obese range, for middle-aged and older adults.