Abstract

Diabetes mellitus is a metabolic disease assuming hyperglycemia as its main symptom, and the number of patients has continued increasing all over the world. Its major complications such as neuropathy, nephropathy and retinopathy by microangiopathy and cerebral vascular disease and heart disease by macroangiopathy, are well known. Recently it has been recognized that hip fracture risk is increased in diabetics as compared with nondiabetics. Although increasing risk of falls due to neuropathy, deterioration of muscle strength and retinopathy seems to be associated with fracture risk, it has been shown that deterioration of bone per se decreases bone strength and causes fractures in diabetes mellitus. Diabetes mellitus and osteoporosis had previously been considered as quite different diseases in pathogenesis or pathology, but it has been clarified that these two diseases have some common factors such as insulin, oxidative stress and advanced glycation end products. So recently the relationship between diabetes mellitus and hip fracture has attracted attention, and it has been suggested that various factors related to diabetes such as glycemic control, insulin sensitivity and so on are associated with bone fragility. It has been shown that bone strength is determined by bone mineral density and bone quality, and it has been suggested in particular that deterioration of bone quality is related to increased fracture risk in diabetics. Exercise therapy is well known as one of the basic treatments for glycemic control as well as diet therapy or pharmacotherapy, and many studies about its effects have been published. However, few studies concerning the effects of exercise therapy in preventing bone deterioration have been conducted. In this review, we describe bone deterioration and its mechanism in diabetes mellitus and the effects of exercise therapy on bone properties, including our own findings.

Keywords: Diabetes mellitus; Osteoporosis; Fracture risk; Bone mineral density; Bone quality; Exercise therapy