[Effect of physical and athletic activity on spinal deformities due to osteoporosis]

Physical activity is associated with increased bone mass and reduced risk of hip fracture. However, scarce are data from population samples concerning the effect of level of physical and sport activity on the risk of osteoporotic vertebral deformity. The aim of the study was to determine the amount of physical and sport activity and to relate it to occurrence of vertebral deformity in older population. In total 425 subjects (269 women and 156 men) age 50 and above, were recruited from a population frame sample, as a random sample of city of Zagreb. An interviewer-administered questionnaire was used to get information about level of physical and sport activity in three different age periods (15-24 years, 25-49 years and 50 years and above), and the amount of time spent walking or cycling each day. Lateral thoracolumbar radiographs were taken using standardised procedure. Radiographs were evaluated morphometrically and the presence of vertebral deformity was defined according to method of McCloskey and al., with an alternative approach for defining normal values using iterative algorithm described by Melton and al. Vertebral deformities were found in 50 (11.8%) subjects. Men were more involved in sports activities in all three life periods, and had heavier overall physical activity from 15-24 years. Although results suggest possible decreased risk for vertebral deformity with stronger physical activity in the first life period, no significant association was found between physical or sport activity and vertebral deformities, even when possible confounding factors were taken in account. Current walking or cycling, adjusted for possible confounders, did not change the risk for vertebral deformities, too. Various confounding factor, different from those taken in account for this study or inadequately large sample for sport activity could have influence the results. We conclude that men are more physically active in younger age, and overall do more sports. Warning is the fact that appreciable proportion of men and women do not do any sport activity. We could not confirm that level of physical or sport activity, as well as regular walking or cycling was significantly important for occurrence of vertebral deformities. Prospective studies are needed in order to understand better the epidemiology and the role of possible risk factors of osteoporotic vertebral deformities in our population, which can help us in planning programs of prevention.