Body Composition and Incident High‐Intensity Back Pain and/or High Disability: A 10‐Year Prospective Population‐Based Male Cohort

ABSTRACT Background Back pain poses a significant global burden, within which individuals with more severe symptoms consume higher healthcare expenses than those with lesser back pain. Whether measures of body composition predict high‐intensity back pain and/or high‐disability in population‐based cohorts is unknown. This study aimed to examine the association between body composition at baseline and their change in the prior 5 years (between 2001–2005 and 2006–2010) and incident high‐intensity back pain and/or high‐disability in long‐term follow‐up, 10 years later (2016–2021) in a population‐based cohort of men. Method This study examined men with no or low‐intensity back pain and disability (Graded Chronic Pain Scale) at back pain study baseline (2006–2010) within the Geelong Osteoporosis Study. Those developing high‐intensity pain and/or high disability at follow‐up (2016–2021) were identified. Weight, body mass index (BMI), abdominal circumferences, fat mass and lean mass (dual energy X‐ray absorptiometry) were assessed prebaseline (2001–2005) and at baseline. The association of body composition at baseline and change in body composition from prebaseline to baseline with incident high‐intensity pain and/or high disability at follow‐up were examined using multivariable logistic regression. Result Of 695 participants with no or low‐intensity pain and disability at baseline, 441 (62.3%) completed follow‐up with a mean age of 54.3 ± 14.1 years: 37 (8.3%) developed high‐intensity pain and/or high‐disability, 33 (7.5%) developed high‐intensity pain and 14 (3.2%) high disability. No measures of body composition at baseline were associated with incident high‐intensity pain and/or high disability at follow‐up in the whole population. In subgroup analysis, among men aged over 60 years, but not younger, higher lean mass was associated with decreased likelihood of high‐intensity pain and/or high‐disability (odds ratio [OR] 0.86, 95% confidence interval [CI] 0.76, 0.97, interaction p < 0.001). In the whole population, examination of the relationship between change in measures of body composition between prebaseline and baseline, only a one unit increase in BMI, equivalent to 3.1‐kg weight gain, was associated with increased incident high disability (OR 1.63, 95% CI 1.06, 2.51). Conclusion In a population‐based sample, without severe back pain and disability, in older men aged ≥60 years, higher lean mass was protective of incident high‐intensity pain and/or high disability. An increase in BMI, over 5 years, equivalent to 3.1‐kg weight gain, was associated with incident back pain related high disability 10 years later. These results demonstrate another detrimental consequence of weight gain and highlight the importance of maintaining muscle mass in older men.