BACKGROUNDHyperostosis is a common pathological change among people more than 50 years old; it is connected with many risk factors, which are all indefinite. The aim of this study was to prospectively investigate the correlation between obesity and female hyperostosis.

METHODSTotally 4326 females were included in this study and their basic information including their age, stature, body weight, course of disease, symptoms, medical complications, frequency of exercise and smoking, and X-ray and bone mineral density (BMD) examination results, was carefully collected for a statistical analysis. The t test or chi(2) test was used to evaluate the differences between two groups; an analysis of variance (ANOVA) was used to evaluate the differences among several groups; the relationship between hyperostosis and body mass index (BMI), age, medical complications, exercise, average BMD was analyzed using Logistic regression.

RESULTSThe incidence rate of hyperostosis in obese patients was higher than that in patients with normal weight (P = 0.000). Obesity was relevant to hyperostotic sites (P = 0.000), and the incidence of hyperostosis in one or several sites of the lumbar vertebrae, knee joints, and other sites was higher in obese patients than in patients with normal weight. There was also a difference in the extent of hyperostosis between these two groups. BMI had positive effects on the incidence and degree of hyperostosis, which were also relative to the sites of hyperostosis, and the BMI of patients without hyperostosis were much lower than those of the patients with hyperostosis in their lumbar vertebrae, knee joints, or multiple sites. Obesity, age, and exercise had positive effects on the incidence of hyperostosis (P = 0.002, 0.000, 0.018).

CONCLUSIONSObesity is a significant potential stimulant of hyperostosis, especially hyperostosis in knee joints and multiple sites; keeping fit might be an important way to prevent it.