Prevalence and Associated Factors of Central Sensitization Among Patients with Chronic Low Back Pain at Mbarara Regional Referral Hospital, Uganda: A Cross-Sectional Study

Abstract

Background: Chronic low back pain (CLBP) is a leading cause of disability worldwide and is increasingly recognized as a condition influenced by altered central pain processing. Central Sensitization (CS), characterized by amplified nociceptive signaling within the Central Nervous System (CNS), may contribute to persistent pain, disability and poor treatment response in patients with CLBP. Despite the high burden of CLBP in Uganda, there is lack of local epidemiological data on CS. This study determined the prevalence and associated factors of CS among patients with CLBP attending Mbarara Regional Referral Hospital (MRRH). Methods: A hospital-based cross-sectional study was conducted among 304 consecutively recruited adults with CLBP attending MRRH between October 2025 and January 2026. CS was assessed using the Central Sensitization Inventory (CSI), with a score ≥40 defining CS. Sociodemographic, clinical, psychological, and lifestyle data were collected using interviewer-administered questionnaires. Modified Poisson regression identified factors independently associated with CS. Results: The mean age of participants was 56.5 ± 16.2 years, and 55.9% were female. The prevalence of CS was 33.9% (n=103; 95% CI: 28.9-39.4). Moderate to severe anxiety (aPR=3.24, 95% CI: 2.27-4.63), depression (aPR=1.63, 95% CI: 1.24-2.16), smoking (aPR=1.41, 95% CI: 1.04-1.91), opioid use (aPR=1.36, 95% CI: 1.02-1.81) and topical analgesics (aPR=1.43, 95% CI: 1.004-2.04) were independently associated with CS. Conclusion: Approximately one-third of patients with CLBP at MRRH exhibited features of CS. CS was associated with psychological distress, smoking, and certain analgesic use patterns. These findings reinforce the need for a biopsychosocial model of care in the assessment and management of CLBP, incorporating evaluation of central pain mechanisms, psychological distress, and other social factors that contribute to pain and disability, while prospective longitudinal studies are needed to clarify temporal relationships and causal pathways.