Prevalence and magnitude of osteopenia associated with insulin-dependent diabetes mellitus.

ABSTRACT

The authors evaluated the prevalence, magnitude, and contributing factors for osteopenia in insulin-dependent diabetes mellitus (IDDM). We measured bone mineral density (BMD) in the lumbar spine and femoral region in 90 patients aged 18-54 years with IDDM using dual-energy x-ray absorptiometry. The blood-glucose control, insulin dosage, duration of disease, and presence of chronic complications of diabetes were evaluated. Serum ionized calcium, magnesium, phosphorus, alkaline phosphatase (ALP), 25-hydroxycholecalciferol, immunoreactive parathyroid hormone (iPTH), and urinary calcium, phosphorus, and hydroxyproline were also analyzed. Thirty-one patients (34%) were classified as having a reduced BMD (less than 2 SD below the mean). The comparison between normal and low BMD patients showed that the osteopenics had a tendency to be younger (median, 28 years versus 32 years), showed a higher mean plasma glucose (15.5 +/- 5.0 mmol/L versus 12.9 +/- 3.8 mmol/L; p = 0.018), longer duration of disease (11.2 +/- 2.1 years versus 5.0 +/- 1.3 years; p = 0.004), and needed a higher insulin dosage (56 +/- 17 U/day versus 43 +/- 16 U/day; p < 0.001). There was a positive correlation between mean glucose levels, duration of disease, insulin dosage, and bone-mass decrease. A higher incidence of chronic complications, mainly retinopathy (58% versus 25%) and neuropathy (52% versus 22%) was found in the low BMD group. There was no alteration of serum calcium, phosphorus, iPTH, 25-hydroxycholecalciferol, and urinary calcium and phosphorus. The ALP levels were significantly higher in the osteopenic group, and magnesium and hydroxyproline levels were lower in the whole diabetic group, but these measurements did not correlate with BMD reduction.(ABSTRACT TRUNCATED AT 250 WORDS)