RE04 : the Relationship Between Smoking Status Quantified by Cotinine Level and Osteoporosis in Postmenopausal Women

Objective: Previous studies have shown that smoking is a risk factor for osteoporosis in postmenopausal women. However, the impact of secondhand smoking(SHS) on osteoporosis is controversial. In this study, we aimed to evaluate the effect of smoking status defined by cotinine level on osteoporosis in postmenopasal women. Cotinine is considered an accurate biomarker for assessing exposure of cigarette smoking. Methods: The study was conducted with data from the Korea National Health and Nutrition Survey from 2009 to 2010, total 1452 postmenopausal women aged 41 years or older out of a total of 19491 were included. Early postmenopausal before the age of 40, hormone replacement treated groups and the groups with PTH 65 or higher were excluded. The cut-off values for cotinine were calculated using Youden’s method. Descriptive analysis, linear regression and logistic regression analysis was conducted to evaluate the aim this study. Results: Smoking status were divided into four groups by urine cotinine level: (1) never smoker was define as urine cotinine level 729.565ng/mL. Logistic regression analysis showed a statistically significant positive correlation between smoking status and femur neck osteoporosis. This correlation was consistent even after adjusting for age and BMI. SHS was not related with osteoporosis. Associations between smoking status and osteoporosis of other sites were not observed. Conclusion: In conclusion, the rate of osteoporosis of femur neck is associated with smoking status in postmenopausal Korean women older than age 40. SHS was not associated with osteoporosis.