Associação entre características clínicas, funcionais e psicossociais com o risco de cronicidade dos sintomas em pacientes com dor lombar crônica não específica

Abstract

Background: Low back pain is considered the leading cause of disability worldwide. Central sensitization is one of the mechanisms that explains how dysregulation in the central nervous system can modulate the chronicity of low back pain; however, it is unclear how clinical, functional, and psychosocial variables are associated with the risk stratification of low back pain chronification. Objective: To verify the association between low and high risk of symptom chronicity and clinical, functional, and psychosocial findings in patients with non specific chronic low back pain. Methods: This is a cross-sectional study applied to individuals with non-specific chronic low back pain, following the recommendations of The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE), conducted between April 2023 and June 2024. The Numerical Pain Rating Scale (NPRS) and the INSTRUTHERM DD2000 20K pressure algometer were used to assess pain intensity and threshold; the Roland-Morris Disability Questionnaire (QRM) to assess functional disability; the Start Back Screening Tool (SBST) for chronicity risk stratification; the Pain Catastrophizing Scale (PCS), the Tampa Scale for Kinesiophobia (TSK), and the Hospital Anxiety and Depression Scale (HADS). Descriptive statistics were performed, and correlation tests were conducted between SBST stratifications of chronicity and the scores from the evaluation instruments. Additionally, multinomial regression analyses were employed. Results: A total of 150 participants were included in the analysis. The correlation between low chronicity risk and clinical, functional, and psychosocial parameters showed statistically significant and moderate negative correlations for the QRM (r = -0.40) and PCS (r = -0.48). Significant, positive, and moderate correlations with high chronicity risk were observed for the QRM (r = 0.40) and PCS (r = 0.48), while positive and weak correlations were found for TSK (r = 0.39) and HADS (r = 0.27). Moreover, the multinomial regression analysis between high and low chronicity risk identified functional disability as a significant predictor for the elevated chronicity risk. For each one-unit increase in the disability questionnaire, the odds of being in the high-risk group increased by 8.8% (OR = 1.088, 95% CI: 1.003 - 1.181, p = 0.043). Additionally, catastrophizing was also a significant predictor. Each additional unit in the catastrophizing score increased the odds of being classified in the high-risk chronicity group by 10.0% (OR = 1.100, 95% CI: 1.049 - 1.154, p < 0.001). The model presented a significant intercept (β = -4.621, p < 0.001), indicating that, in the absence of predictor factors, the probability of being in the high-risk chronicity group is extremely low (OR = 0.009, 95% CI: 0.002 - 0.043). Conclusion: These findings suggest that the probability of being at high risk of chronicity compared to low risk was 36.8%, explained by functional disability and pain catastrophizing.