Biomarkers of chronic nonspecific pain syndrome: A cross-sectional hospital-based pilot study

Abstract

Background: More than 50 million American have chronic pain and 41% of them have poor response to the treatment. One large survey on Chronic Pain “Pain in Europe” reported it as 12%–30% in the European countries and 19.3% in a study from west India. Objective: We aimed to look for bio-psycho-social biomarkers for chronic nonspecific pain. Methods: Patients of chronic non-specific pain syndrome (CNPS) defined as “patients presenting with multiple site pain or widespread body pain for more than three days per week for more than 3 months duration without any specific medical, neurological, orthopedic or rheumatologic cause”. All patients were subjected to clinical severity scale (visual analogue score), chronic pain related quality of life (QOL) score (ranges from 0 (Bed ridden stage) to 10 (normal functioning). Then patients were subjected for complete Hemogram, serum ferritin level, serum vitamin B12 level and Vitamin D level and psycho-social screening. Psycho-social assessment done by psychologists for psychometric analysis and tools for central sensitization inventory (CSI) to find out sensitization index, Pittsburg sleep quality index (PSQI) for sleep quality, Hospital anxiety and depression scale (HADS), and Somatic symptom scale – 8 (SSS – 8) to know somatization index. Results: Among 120 patients absolute deficiency of ferritin, vitamin B12 and Vitamin D was found in 51 (42.5%), 40 (33.3%) and 60 (50%) patients respectively. High sensitization index (CSI > 50) and high somatization index (SSS-8 of > 12) was found in 22 (17.5%) and 27 (23.3%) patients respectively. Patients with low ferritin had better outcome. Conclusion: This bio-psycho-social model for chronic pain will help the clinicians and patients for better understanding of the problem and better prediction for outcome.