Depressive symptoms score and risk of incident spinal pain in middle-aged and elderly populations: a prospective cohort study based on china health and retirement longitudinal study data.

BACKGROUND

Spinal pain is a common musculoskeletal disorder, the leading cause of disability in middle-aged and elderly populations (females more affected), burdening quality of life, function, and socioeconomic status. It is frequently comorbid with depressive symptoms via bidirectional mechanisms: chronic pain induces depressive symptoms through neuroendocrine and immune dysfunctions, while depressive symptoms exacerbates pain by lowering pain thresholds and promoting negative coping. Previous studies on their association have limitations (unclear causality, inadequate confounder control, insufficient population heterogeneity attention, underexplored dyslipidemia regulatory role), requiring large-scale population-based studies.

AIM: Explore the association and dose-response relationship between depressive symptoms scores and incident spinal pain risk in middle-aged and elderly populations, analyze dyslipidemia's moderating/mediating effects, and provide a scientific basis for precise prevention and intervention of spinal pain.

DESIGN

Prospective cohort study.

SETTING

Nationwide communities/villages in China, based on the China Health and Retirement Longitudinal Study (CHARLS).

POPULATION: Overall, 3934 middle-aged and elderly individuals (≥45 years, no baseline spinal pain) from CHARLS (excluding those with baseline spinal pain, age <45 years, incomplete/missing information). During follow-up, 223 developed incident spinal pain. Median age 57.8 years (52.41% males, 47.59% females). Those with incident spinal pain were more likely to be female, have lower education, be non-smokers/non-drinkers, shorter nighttime sleep, higher depressive symptoms scores, and a higher proportion of heart disease.

METHODS

Data Source: 9-year CHARLS longitudinal data (2011-2020), stratified and probability proportional sampling.

RESULTS

depressive symptoms scores were significantly positively correlated with incident spinal pain risk: each 1-point increase (fully adjusted model) was associated with an 8% higher risk (OR=1.08, 95% CI:1.05-1.11, P<0.0001), and the highest quartile had a 2.58-fold higher risk than the lowest (OR=2.58, 95% CI:1.81-3.67, P<0.0001). RCS analysis confirmed a linear dose-response relationship (P for non-linearity = 0.392) with a critical threshold of ~2.1. The correlation was stable across most subgroups; dyslipidemia had a significant moderating effect (P=0.006, weaker association in those with dyslipidemia), while sleep duration and smoking status had marginal effects. depressive symptoms scores, total effect on spinal pain was significant (coefficient = 0.00270, 95% CI: 0.00198-0.00327, P<0.001), but the indirect effect through dyslipidemia was not (coefficient = -0.00002, 95% CI: -0.00021-0.00015, P=0.840) with negligible mediation (-0.1%). Results were robust.

CONCLUSIONS

Community-dwelling middle-aged and elderly populations have an independent linear dose-response relationship between depressive symptoms scores and incident spinal pain risk: each 1-point increase raises risk by 8%, the highest quartile has a 2.58-fold higher risk, and ~2.1 is the critical threshold. Dyslipidemia significantly moderates this association. with robust findings providing key evidence for the depressive symptoms-spinal pain relationship.

CLINICAL REHABILITATION IMPACT: According to the ICF (International Classification of Functioning, Disability and Health) model, the interaction between depression and spinal pain is not merely a physiological impairment, but a health disorder spanning multiple dimensions: Body Functions & Structures: Depression symptoms (b152 emotional function) reduce the pain threshold through central sensitization (b280 pain perception), leading to an exacerbated sense of spinal integrity damage. Activities & Participation: The comorbidity of pain and emotion limits the patient's daily activities (d450 walking) and social participation (d9 community life), forming a "degenerative cycle." Environmental & Personal Factors: The lipid status, educational level, and gender confirmed in this study are key background regulatory factors that affect the trajectory of functional recovery. Comprehensive intervention strategy suggestions: Graded screening: For community-dwelling elderly individuals with a CESD-10 score exceeding 2.1, immediate spinal health assessment should be initiated. Integrated treatment: Adopt a "psychological-physical" combined intervention, such as psychological-guided physical therapy (PIP) and preoperative rehabilitation based on exercise, to simultaneously improve emotional disorders and physical pain. Metabolic monitoring: For those with high depression risk but without abnormal blood lipids, more rigorous psychological counseling is required; while for those with abnormal blood lipids, priority should be given to controlling metabolic indicators to reduce systemic inflammatory load.