Relationship between Obesity and Lumbar Spine Degeneration: A Cross-Sectional Study from the Fifth Korean National Health and Nutrition Examination Survey, 2010-2012

Background: Although several studies have shown that obesity affects low back pain (LBP), the relationship between degenerative lumbar spine (LSD) and obesity has not been fully investigated. This study evaluated whether obesity is independently associated with LSD in the general population. Methods: This cross-sectional study used public data from the Fifth Korean National Health and Nutrition Examination Survey (2010-2012). Subjects aged ≥50 years who had completed surveys were included (3668 men and 4966 women). Obesity was classified based on the body mass index, and LSD was assessed by lumbar spine radiographs. Independent associations of obesity with LSD or LBP were determined using odds ratios (OR) adjusted by two regression models. Results: The prevalence of obesity was more frequent in women than in men (38.27% vs. 33.97%, P < 0.001). Compared with normal weight women, the risk of LSD was increased in overweight and obese women following adjustments [OR = 1.227, 95% confidence interval (CI): 1.019-1.477; OR = 1.217, 95% CI: 1.024-1.446, respectively]. When obesity was subdivided, the obese II group showed higher odds for LSD in women (OR = 1.797, 95% CI: 1.287-2.510). However, obesity was not correlated with LSD in men. There was no significant association between obesity and LBP in either men or women. Conclusions: Compared with normal weight women, LSD risk was higher in overweight and obese women, especially those in the obese II subgroup. These findings suggest that maintaining normal body weight may be a preventative factor of LSD.