RISK-FACTORS FOR HIP FRACTURE IN MIDDLE-AGED NORWEGIAN WOMEN AND MEN

Data from a prospective study were used to investigate risk factors fo r hip fracture among a representative population of middle-aged adults . During the years 1974-1978, all women (n = 25,298) and men (n = 27,0 15) aged 35-49 years in three Norwegian counties were invited to atten d a cardiovascular screening (attendance rate = 91.5%). This cohort wa s followed throughout 1990 with respect to hip fracture, for a total o f 572,006 person-years. A total of 281 new fractures were identified, of which 71 were excluded from the analysis due to high-energy trauma or fracture in metastatic bone. Age-adjusted relative risks (RR) and 9 5% confidence intervals (CI) for hip fracture increased with body heig ht in women (RR = 3.62, 95% CI 1.46-8.97, greater-than-or-equal-to 1.7 0 m vs. < 1.55 m) and men (RR = 2.92, 95% CI 0.94-9.05, greater-than-o r-equal-to 1.85 m vs. < 1.70 m). A history of diabetes mellitus also g ave elevated risk of fracture (RR = 5.81, 95% CI 2.15-15.71 in women a nd RR = 7.67, 95% CI 2.40-24.53 in men). In addition, hip fracture was related to body mass index (inverse), disability pension, and marital status. An increased risk for smokers appeared only among those consu ming greater-than-or-equal-to 15 cigarettes per day. In multivariate a nalysis, all these risks remained elevated. This study suggests that, as in older populations, known risk factors for low bone mass are rela ted to hip fracture among middle-aged adults. In addition, body height seems to have an independent influence on hip fracture incidence in t his age group.