Protein intake and bone disorders in the elderly

Malnutrition, most notably protein deficiency, contributes to the occurrenc e of osteoporotic fractures not only by decreasing bone mass but also by al tering muscle function. Furthermore, malnutrition is associated with increa sed morbidity in patients with osteoporotic fractures. The somatomedin syst em (IGF-1) may be directly involved in the pathogenesis of osteoporotic hip fractures and their complications in elderly patients. A low IGF-1 level i s a risk factor for hip fracture. In subjects with appropriate intakes of v itamin D and calcium, giving protein supplements to correct an inadequate s pontaneous protein intake increases circulating IGH levels, improves clinic al outcomes after hip fracture, and prevents bone mineral density loss at t he proximal femur. Supplemental protein also significantly reduces the leng th of inpatient rehabilitation care. These data emphasize the importance of adequate nutrient intake in the prevention and treatment of osteoporotic f ractures. Joint Bone Spine 2001; 68 : 383-92. (C) 2001 Editions scientifiqu es et medicales Elsevier SAS.