Spine-Hip Thickness Difference Measured by Dual-Energy X-ray Absorptiometry Is Associated With Diabetes Mellitus in Women and Men.

Abdominal adiposity is strongly associated with a range of chronic metabolic and cardiovascular morbidities, including type 2 diabetes mellitus, and may play a causal role in their development. Dual-energy X-ray absorptiometry (DXA) of the lumbar spine and hip is widely used for assessment of osteoporosis and also measures tissue thickness. We hypothesized that the difference in spine and hip tissue thickness from regional DXA scans might provide an index of relative abdominal adiposity and serve as a risk factor for the presence of diabetes. We identified 31,648 women and 2960 men aged ≥50 yr who underwent spine and hip DXA scans and analyzed their baseline characteristics, including presence of previously diagnosed diabetes in 2929 women and 460 men. Women had significantly lower mean spine-hip thickness differences than men (3.3 ± 1.4 cm vs 5.4 ± 1.7 cm; p < 0.001), which persisted after adjustment for sex-specific differences in the effects of age and body mass index (BMI). Women and men with diabetes had significantly higher mean spine-hip thickness differences before and after adjustment for age and BMI. Logistic regression showed that greater spine-hip thickness difference was significantly associated with higher likelihood of diabetes even after adjustment for age and BMI, and this effect was stronger among women (odds ratios per standard deviation 1.88 [95% confidence interval: 1.86-1.98]; p < 0.001) than among men (1.10 [1.03-1.18]; p = 0.007). We conclude that spine-hip thickness difference measured from regional DXA scans warrants further study as a risk factor for developing diabetes.