Association Between Sarcopenia and the Long-Term Risk of Intervertebral Disc Degeneration

Sarcopenia and intervertebral disc degeneration (IDD) are both highly prevalent among the elderly and have a substantial impact on their quality of life. However, the association between sarcopenia and IDD remains unclear. This study aimed to investigate whether sarcopenia is independently associated with an increased risk of IDD in middle-aged and older adults, using prospective data from the UK Biobank.

A total of 378 773 participants from the UK Biobank were included and categorized into three groups based on the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) criteria: normal, probable sarcopenia and confirmed sarcopenia. The association between sarcopenia and IDD was examined using Kaplan-Meier survival analysis and Cox proportional hazards models. Sensitivity analyses included subgroup analyses to assess the robustness of findings and interaction tests to explore potential effect modifiers.

The median age of participants was 59 years, with females accounting for 54.8% of the cohort. Over a median follow-up duration of 171 months, 10 585 participants developed IDD. In unadjusted Cox regression analyses, compared to the normal group, the hazard ratios (HRs) for IDD were 1.51 (95% CI: 1.41-1.61) in the probable sarcopenia group and 1.47 (95% CI: 1.14-1.90) in the confirmed sarcopenia group. After adjusting for multiple covariates, the corresponding HRs were 1.35 (95% CI: 1.26-1.44) and 1.41 (95% CI: 1.10-1.80), respectively. These associations remained consistent across subgroup analyses. Notably, in BMI-stratified analyses, individuals with sarcopenia and a BMI > 25 had a higher risk of IDD (HR: 1.88; 95% CI: 1.31-2.71) compared to those with BMI ≤ 25 (HR: 1.51; 95% CI: 1.06-2.16), with a significant interaction (p < 0.001).

Sarcopenia is associated with an increased risk of IDD, particularly in overweight or obese individuals. Regular assessment of muscle strength and mass, along with promoting physical activity and adequate nutritional interventions in ageing populations, may help prevent sarcopenia and delay the onset of IDD.