Bone density in non-insulin-dependent diabetes mellitus. The Rotterdam Study.

OBJECTIVE: To investigate the relation between non-insulin-dependent diabetes mellitus and bone mineral density at the lumbar spine and hip.
DESIGN: Population-based study with a cross-sectional survey.
SETTING: A district of Rotterdam, the Netherlands. PARTICIPANTS: 5931 residents (2481 men, 3450 women) of the district aged 55 years or more. MEASUREMENTS: Participants were classified as having non-insulin-dependent diabetes mellitus if they were receiving antidiabetic medication or if they had a serum glucose level of 11.1 mmol/L or more after a nonfasting oral glucose tolerance test. Bone mineral density, measured at the lumbar spine and proximal femur using dual-energy x-ray absorptiometry and the frequency of nonvertebral fractures during the preceding 5 years were compared between persons with and without non-insulin-dependent diabetes mellitus.
RESULTS: 243 men and 335 women had non-insulin-dependent diabetes mellitus. Both men and women with this condition had substantially higher mean bone mineral density values at all four sites measured than those with normal glucose tolerance. The increase could not be explained by age; obesity; use of estrogens, thiazides, or loop diuretics; impairment in abilities of daily living; smoking; or osteoarthritis. Women with non-insulin-dependent diabetes mellitus reported having had fewer fractures in the 5 preceding years than women without this condition (adjusted odds ratio, 0.63; 95% CI, 0.44 to 0.90). The frequency of fractures in men was similar for those with and without non-insulin-dependent diabetes mellitus (adjusted odds ratio, 0.96; CI, 0.60 to 1.52).
CONCLUSIONS: Men and women with non-insulin-dependent diabetes mellitus have increased bone mineral density. Non-insulin-dependent diabetes mellitus in women is associated with a lower frequency of nonvertebral fractures.