BODY HEIGHT, BODY-MASS-INDEX, AND FATAL HIP-FRACTURES - 16 YEARS FOLLOW-UP OF 674,000 NORWEGIAN WOMEN AND MEN

We studied the relations between body height, body mass index (BMI), a nd fatal hip fractures prospectively in a large, representative popula tion. During the years 1963-1975, a nationwide compulsory mass x-ray e xamination including standardized height and weight measurements took place in Norway covering all persons age 15 years and older. In the st udy presented here, we selected women (N = 357,807) and men (N = 316,0 41) age 50-89 years at screening. We matched the file to the national death register containing causes of death throughout 1991; we defined cases as persons with hip fracture mentioned on their death certificat es. During an average follow-up of 16.4 years, we identified a total o f 6,087 fatal hip fractures in the study population. There was a disti nct inverse relation between BMI and fatal hip fracture, with an age-a djusted relative risk (RR) in the three highest us the low quartile of 0.68 [95% confidence interval (CT) = 0.63-0.72] in women and 0.57 (95 % CI = 0.52-0.62) in men. The risk of fatal hip fractures increased sl ightly with increasing body height [RR = 1.10 (95% CI = 1.04-1.16) in women and RR = 1.08 (95% CI = 1.01-1.16) in men per 10-cm increase in body height]. This study indicates that low BMI is an important risk f actor for fatal hip fractures and that body height has a weak, positiv e association.