Association of lifestyle factors with osteoporosis and fracture in postmenopausal women: a Japanese cohort study

OBJECTIVE: Osteoporosis is a major risk factor for fracture later in life; however, few studies have examined the association of lifestyle factors with osteoporosis and fracture. This study aimed to identify factors associated with osteoporosis and fracture in postmenopausal women. METHODS: We evaluated the association between baseline characteristics and outcomes (diagnosis of osteoporosis or incidence of fracture) in 4,427 postmenopausal women who participated in the Kyushu University Fukuoka Cohort Study on lifestyle-related diseases (baseline: February 2004 to August 2007; follow-up: February 2010 to December 2012). Among the women, 626 were diagnosed as having osteoporosis without a fracture, 294 sustained a fracture without a diagnosis of osteoporosis, and 137 were diagnosed with both osteoporosis and fracture during the average 5.3-year follow-up period; the remaining 3,370 participants were not diagnosed with osteoporosis or did not sustain a fracture. The association between lifestyle factors and the occurrence of osteoporosis and fracture was evaluated using logistic regression analysis. RESULTS: Skipping breakfast was associated negatively with osteoporosis without fracture (odds ratio [OR] = 0.40, P = 0.009) but positively with fracture without osteoporosis (OR = 2.30, P = 0.0009). Glycated hemoglobin A1c levels were associated negatively with osteoporosis without fracture (OR = 0.81, P = 0.0003) but positively with fracture without osteoporosis (OR = 1.18, P = 0.03). Parental history of fracture and extraversion personality trait were both associated with fracture without osteoporosis. CONCLUSIONS: Osteoporosis and fracture showed different association patterns with lifestyle factors, and no factors were correlated with an increase in both osteoporosis and fracture.