Older individuals with vs without chronic low back pain (CLBP) may have lower skeletal muscle mass, according to a study published in Osteoporosis and Sarcopenia.
A total of 100 participants (>65 years; mean age, 74.4 years; 55% women) with CLBP symptoms for ≥3 months and 560 individuals without CLBP (mean age, 73.2 years; 45.7% women) were enrolled between 2011 and 2015 for this prospective study. Participants were asked to report pain intensity using a 0 to 10 visual analog scale (VAS) and to complete the Roland Morris Disability Questionnaire (RDQ).
Whole-body dual-energy X-ray absorptiometry (DEXA) scans were used to measure skeletal muscle mass index (SMI) and body fat percentage, and sarcopenia was defined as a relative SMI >2 standard deviations below the mean SMI for young adults, yielding cutoffs for SMIs of 6.87 kg/m2 and 5.46 kg/m2 for men and women, respectively. Cutoff values for sarcopenic obesity were 28% and 40% body fat for men and women, respectively. Magnetic resonance imaging was used to calculate cross-sectional areas (CSA) of the erector spinae and multifidus paraspinal muscles.
The following characteristics were found to be different between individuals with vs without CLBP: weight (56.4 kg vs 59.2 kg, respectively; P <.05), VAS (6.5 vs 2.8, respectively; P <.01), and RDQ (16.9 vs 12.9, respectively; P =.0425). A total of 189 participants (28.6%) with sarcopenia were identified, a higher percentage of whom had comorbid CLBP vs no CLBP (40% vs 26.6%, respectively; P <.01). Participants with vs without CLBP had a lower mean SMI, as indicated by DEXA scans (P =.0133 for men and P =.0295 for women) and a higher mean body fat ratio (P <.001 for men and P <.0001 for women). Bone mineral density was comparable in both groups. There was significant sarcopenic obesity observed in patients in the CLBP group (P <.05), and the lumbar CSA was lower in both paraspinal muscles in patients with vs without CLBP.
Study limitations include a cross-sectional design and a lack of evaluation of skeletal muscles, including walking speed and grasping force.
“Therapeutic procedures that are used to treat elderly aging muscle, including muscle strengthening and performance training, can possibly be a treatment for or used to prevent elderly CLBP,” suggested the authors.
Sakai Y, Matsui H, Ito S, et al. Sarcopenia in elderly patients with chronic low back pain. Osteoporos Sarcopenia. 2017;3(4):195-200.