ABSTRACTIntroduction: Low weight and obesity are risk factors for osteoporosis in postmenopausal women; however, the influence of its change on a therapeutic response to biophosphonates for the prevention of fractures has not been defined yet. Objective:To describe the association between the body mass index (BMI) and bone mass in postmenopausal women, as well as to identify changes in weight and BMI during the treatment with biophosphonates. Material and methods: Weight, height, and BMI was determined in 296 women who came consecutively to the Climateric and Osteoporosis Clinic (ClimOS) in Havana from 2009 to 2014 (n=103), and to the Department of Metabolic Bone Diseases, Jiménez Díaz Foundation, Madrid (n=193); also, bone mineral density in lumbar spine and hip was measured by DXA. The influence of initial body weight and its temporal variation with the use of biophosphonates (BPS) was evaluated in 80 of them. Statistical analysis: standard statistical average for qualitative variables, frequencies for the qualitative variables, Student´s t-Tests, and X2 test for differences among them. Pearson´s correlation to specify the influence of the initial weight and BMI, and their differences in the response to biophosphonates. Besides, p<0,05 value was used for statistical significance. Results: Low weight was identified 4/296; more than half of them were overweight or obese. Women who were evaluated in ClimOs, presented a worse bone status on the hip. Neither association of body weight nor BMI was found on the response to treatment with (BPS). Conclusions: The influence of body weight on a new fracture was controversial; it is suggested to include ponderal variation as part of the treatment for osteoporosis.Keywords: menopause, osteoporosis, body mass index, biophosphonates, body composition.</p
