Prevalence and contributing factors of osteoporosis in the elderly over 70 years old: an epidemiological study of several community health centers in Shanghai

Abstract

Background: OP seriously affects the health status and quality of life of the elderly, even endangers life. This study aimed to investigate the prevalence and contributing factors of osteoporosis (OP) in the elderly over 70 years old of several Community Health Centers in Shanghai.

Methods: A total of 565 elderly subjects were recruited and received questionnaire survey. The general characteristics, medical history and history of OP treatment were collected. Bone mineral density (BMD) was detected, and the awareness rate, prevalence and treatment rate were determined in all of the subjects. Moreover, activity of daily living and nutritional status were also evaluated. Logistic regression analysis was performed to calculate the OR and its 95% confidence interval. Bone turnover markers (BTMs) [procollagen type 1 N-peptide (P1NP), C-terminal cross-linked telopeptides of type 1 collagen (β-CTX), molecular fragment of N-terminal osteocalcin (N-MID), and 25 hydroxyvitamin D (25OHD)] were detected and their relationship with OP was further evaluated with Pearson correlation analysis.

Results: : (I) The awareness rate of OP was 89.7%, the prevalence was 39.5%, and the treatment rate was 59.5% in the elderly over 70 years old of 4 Community Health Center in Shanghai; (II) the male gender and good nutritional status were independent protective factors of OP, and aging and poor activity of daily living were independent risk factors of OP; (III) β-CTX was negatively related to BMD (r=-0.286, P=0.000), but P1NP, N-MID, and 25OHD were positively related to BMD (r=0.254, 0.349 and 0.357, P=0.000, 0.000 and 0.000).

Conclusions: Female gender, aging, malnutrition, and inability to take care of themselves are risk factors of OP in people over 70 years old of 4 Community Health Centers in Shanghai. Some BTMs are related to the BMD. BTMs together with BMD may be used to comprehensively evaluate the bone state, identify the old people with OP at early stage, and guide the clinical treatment and early monitoring of OP.

Keywords: Elderly; bone turnover markers (BTMs); epidemiology; osteoporosis (OP); risk factors.