Higher levels of fat mass were found to be associated with higher intensity of back pain and related disability in adults, according to a study published in Arthritis Research & Therapy.
A total of 150 individuals aged 25 to 60 years (mean age, 48.6 years; mean body mass index, [BMI], 32.0 kg/m2) who had undergone dual-energy x-ray absorptiometry within 12 months of answering the Chronic Pain Grade Scale between 2008 and 2009 were enrolled in this study. Of those participants, 123 (82%) completed the 3-year follow-up. The Short Form-36 was used to evaluate patients’ health-related quality of life, and the mental component summary of the Short Form-36 was used to assess participants’ mental health. Physical activity was also assessed with a questionnaire.
The 7-item, self-administered Chronic Pain Grade Scale was used to assess back pain intensity and related disability. A pain intensity score ≥50 on a 0 to 100 scale was considered high intensity, and a score of 3 on a 6-point scale was considered high disability back pain. Resolving high-intensity back pain was characterized by high-intensity back pain at baseline but not at follow-up, and persistent high-intensity back pain was defined as high-intensity back pain at baseline and at follow-up.
The percentages of participants reporting high-intensity back pain at baseline and at follow-up were comparable (22.8% vs 21.1%, respectively). Individuals who reported high-intensity back pain at any time point also had a higher mean BMI compared with patients without high-intensity back pain (mean BMI: resolving pain, 36.5±7.5 kg/m2; developing pain, 37.0±9.5 kg/m2; persistent pain, 36.4±7.9 kg/m2; no high-intensity back pain, 29.7±7.5 kg/m2; P <.001). Patients with high-intensity back pain at any time point had poorer mental health vs patients who did not experience any high-intensity back pain (mean mental component summary score: resolving pain, 42.1±15.6; developing pain, 42.0±16.9; persisting pain, 40.5±15.0; no high-intensity back pain, 48.9±11.7; P =.003).
There was a 5% increased risk for high-intensity back pain for every 1 kg increase in total body fat mass at baseline during the 3-year study period (odds ratio, 1.05; 95% CI, 1.01-1.09; P =.01) after adjusting for confounding variables. An association was established between a higher android to gynoid ratio and high-intensity back pain (multivariable odds ratio, 1.04; 95% CI, 1.01-1.08; P =.009).
Study limitations include the predominance of women in the cohort (78.1%), and the lack of adjustment for depression in the multivariable analysis.
“The results of this study suggest targeting specifically a reduction in fat mass (not just simply weight loss) to prevent back pain, particularly in those who carry excess fat in the android distribution,” noted the study authors.
Brady SRE, Urquhart DM, Hussain SM, et al. High baseline fat mass, but not lean tissue mass, is associated with high intensity low back pain and disability in community-based adults. Arthritis Res Ther. 2019;21(1):165.