Association Between Body Mass Index and Nonspecific Recurrent Low Back Pain in Over 600,000 Healthy Young Adults

Abstract

Association between body mass index (BMI) and low back pain (LBP) has long been debated, however inconsistent measurements of BMI and varying definition of LBP have produced conflicting findings. We explored this association using measured BMI and a physician documentation of recurrent-LBP among healthy young adults. Data were extracted from the electronic-medical-record system (EMRS) of the Israel-defense-forces (IDF). All compulsory military servants between 2008-2019 were included (n=705,840). Exclusion criteria were spine deformities, disc pathologies, spinal surgery, arthropathies, connective tissue diseases, pain syndromes, low bone density disorders, cancer, and psychiatric diseases. LBP was defined as IDF-EMRS documentation of: 1) two medical visits, at least 6 weeks apart, with a diagnosis of LBP or "LBP with radiation"; or 2) one visit resulting in referral to an orthopedic surgeon. Logistic regression models were used to explore the association between BMI category and LBP, 619,969 (87.8%) individuals (mean 18.9 [SD=0.97] years, 56.9% male) were included. LBP prevalence was 9.2% (n=56,918), higher among males (9.7%) than females (8.5%). Having overweight and obesity was associated with LBP (OR 1.123 [1.096-1.151] and 1.137 [1.096-1.179], respectively). Association remained significant when accounting for various sociodemographic factors. Maintaining healthy BMI may aid in the prevention of LBP in young adults.