Association Between Functional Status (Oswestry Disability Index) And Body Fat Percentage in Patients Aged 30–45 Years with Low Back Pain

Abstract

Introduction: Low back pain is one of the leading causes of medical consultation and work-related disability among adults of productive age. The high prevalence of overweight and obesity in Mexico suggests that body fat percentage may play an important role in functional impairment associated with lumbar pain.

Objective: To determine the association between functional status, measured using the Oswestry Disability Index (ODI), and body fat percentage in patients aged 30–45 years with low back pain treated at a secondary care regional hospital.

Materials and Methods: An observational, analytical, prospective, cross-sectional study was conducted. Ninety-six patients aged 30–45 years with a clinical diagnosis of low back pain under conservative treatment were included. Functional status was assessed using the ODI, and body fat percentage was measured by bioelectrical impedance (Omron HBF-514C), categorized as low, normal, high, or very high. Descriptive statistics were used, and the chi-square test assessed associations. Effect size was estimated using Cramer’s V. A p-value <0.05 was considered statistically significant.

Results: The sample included 56 women (58%) and 40 men (42%), with a predominance of patients aged 36–40 years (46%). According to ODI, 9% had no disability, 16% mild, 45% moderate, 27% severe, and 3% total disability. Regarding body composition, 5% presented low body fat, 18% normal, 58% high, and 19% very high. Patients with high and very high body fat percentages clustered predominantly in moderate, severe, and total disability categories. A statistically significant association was found between body fat percentage and functional status (χ²=120.48; df=12; p=0.000), with a strong effect size (Cramer’s V=0.647).

Conclusion: A higher body fat percentage is strongly and significantly associated with worse lumbar functional status in adults aged 30–45 years with low back pain. Body fat percentage should be considered a relevant clinical indicator during initial evaluation and in planning conservative treatment, prioritizing fat reduction strategies before considering surgical options.