The Relationship Between Type 2 Diabetes Mellitus and Osteoporosis in Elderly People: a Cross-sectional Study

Diabetes mellitus (DM) and osteoporosis are common diseases and their prevalence increases with age. Several investigations have indicated that type 1 DM has a significant relationship with bone loss, whereas in type 2 diabetes, this relationship is controversial. Therefore, this study was conducted to determine the relationship between osteoporosis and type 2 DM in elderly people. This population-based study had been carried out on 1151 elderly people in Amirkola, northern Iran. L2-L4 lumbar spine bone mass and the left femoral neck density were measured by dual-energy X-ray absorptiometry (DEXA). In addition, diagnosis of diabetes was done by measuring fasting blood sugar (twice times FBS ≥ 126 mg/dl), according to the WHO criteria or self-reported as well as based on a doctor's prescription. Of total, 362 (31.45%) of patients had DM. The average age of diabetic patients was 68.9± 6.93 years and in non-diabetic group was 68.68± 7.09 years (P= 0.18). The mean L2-L4 lumbar spine bone mass in the diabetic group was 0.90± 0.19 g/cm2 and in the non-diabetic group was 0.85± 0.18 g/cm2 (P= 0.001). The mean lumbar bone mineral density was higher (P= 0.0001) in diabetic men than in non-diabetic men, as well as in women (P= 0.0001). In addition, the mean femoral neck density in diabetic group was 0.85± 0.16 g/cm2 and in the non-diabetic group was 0.84± 0.15 g/cm2 (P= 0.48). Moreover, the femoral neck bone mineral density in diabetic men was higher than in non-diabetics (P= 0.03), whereas in diabetic and non-diabetic women, there was no significant difference (P= 0.52). Our results demonstrated that the mean lumbar and femur bone mineral densities in older people with type 2 DM was higher than people without DM.