Weight loss: a determinant of hip bone loss in older men and women. The Rancho Bernardo Study.

The sex-specific effect of weight change on change in total hip bone mineral density was evaluated over 4 years (1992-1996) in 1,214 community-dwelling adults whose mean age at baseline was 71 years. Weight and bone mineral density (by dual-energy x-ray absorptiometry) were assessed at two study visits. The average bone loss was 0.5% per year in both sexes; 29% of men and 28% of women lost at least 1% of bone mineral density per year. More than one in five participants lost at least 1% of their body weight per year (21% of men and 23% of women). These weight losers were twice as likely as others to lose bone at the rate of at least 1% per year. In analyses controlling for age, baseline weight, and lifestyle, weight loss was the strongest independent predictor of bone loss (odds ratios were 1.53 for men and 1.56 for women). Persons with weight loss of at least 1% per year were more likely to report fair or poor health and functional limitation at the second visit and to die within 2 years of the second visit; however, most did not report declining health, and most survived for at least 2 additional years.