Clinical Profiles and Functional Limitations in Hospitalized Patients with Chronic Low Back Pain: A Cross-Sectional Study of Comorbidity Burden and Symptom Persistence

Background and Objectives: Chronic low back pain (LBP) is frequently associated with recurrent exacerbations, incomplete symptom resolution, and functional limitations. This study aimed to characterize retrospectively reported symptom patterns over the preceding 12 months in hospitalized adults with chronic LBP and to examine the cross-sectional association between systemic comorbidity burden, assessed using the Age-Adjusted Charlson Comorbidity Index (ACCI), and the absence of sustained pain-free periods. Materials and Methods: This cross-sectional observational study included 97 consecutively enrolled hospitalized patients with chronic LBP (mean age 66.61 ± 10.01 years; 74.2% women; mean body mass index 33.14 ± 6.10 kg/m2). Symptom characteristics over the preceding 12 months, including exacerbation frequency and duration, inter-episode recovery, sustained pain-free periods, and perceived symptom evolution, were assessed using a structured, non-validated clinical questionnaire. Functional limitations were evaluated using a single self-reported item. Comorbidity burden was quantified using the ACCI. Descriptive statistics and 95% confidence intervals (CIs) were calculated, while the association between ACCI and the absence of sustained remission was examined using Spearman correlation and unadjusted binary logistic regression. Results: Frequent exacerbations were reported by 77.3% (95% CI 68.0–84.5) of participants, who experienced at least three episodes annually, including 42.3% reporting six or more episodes. Incomplete inter-episode recovery was reported by 84.5%, while 59.8% (95% CI 49.8–69.0) experienced no sustained pain-free period lasting at least one month. Self-reported functional limitations were present in 92.8% (95% CI 85.8–96.5) of participants, with 56.7% reporting moderate and 36.1% severe limitations. Overall, 66.0% retrospectively reported unchanged or worsening symptoms. The mean ACCI was 3.55 ± 1.75. The association between ACCI and the absence of sustained remission was weak and not statistically significant (Spearman ρ = 0.117, p = 0.253). Unadjusted logistic regression yielded an odds ratio of 1.17 per ACCI point (95% CI 0.92–1.49; p = 0.208). Conclusions: Hospitalized adults with chronic LBP frequently reported recurrent exacerbations, incomplete inter-episode recovery, absence of sustained remission, and substantial perceived functional limitations. No statistically significant association between ACCI and the absence of sustained remission was detected; however, the confidence interval does not exclude a potentially meaningful association. These findings highlight the importance of multidimensional clinical assessment, while the cross-sectional design and retrospective symptom reporting preclude causal, prognostic, or longitudinal interpretations.