Abstract:

Objective To analyze the change of bone strength index (SI) and its relationship with body composition (BC) in Lanzhou Han nationality adults and to provide reference data for prevention and diagnosis of osteoporosis (OP). Methods Ultrasonic bone mineral density meter and Bioelectric impedance technique were used to test the bone strength index of right calcaneus and body composition. A total of 2291 Han nationality adults in Lanzhou（1021 males,1270 females) were sampled. The association between bone strength index and body composition was tested by multiple linear regressing analysis. Results The bone strength index of Lanzhou Han nationality adults presented tendency of decrease along with age, and the peak of bone mass (PMB) occurred at 20-30 years old. The SI in male decreased rapidly between 20-30 and 50-60 years old, and the SI in female fell fast beyond 50 years old. The SI in male was higher than female at each age group. Compared with other nationalities by using the same method, the mean values of SI and PMB were lower in Lanzhou Han nationality adults and PMB in Lanzhou Han female, respectively. According to the analysis of multiple linear regressing between SI and BC，both muscle mass and subcutaneous fat mass, and body mass index(BMI) were positively associated with SI, visceral fat mass was negatively correlated with SI. Conclusion The SI and PMB values are respectively lower in Lanzhou Han nationality adults and Lanzhou Han female. The PMB appeares early in youth. Females above 50 years old are a higher risk population of OP. Muscle mass, subcutaneous fat mass and BMI are protective factors for OP while visceral fat mass is a factor of risk for OP.

Key words: Lanzhou, Han nationality, Bone strength index, Osteoporosis, Body composition, Bioelectric impedance technique, Adult