The association between common mental disorders and tuberculosis: a case-control study from Guinea-Bissau

Objective: The aim of the study was to explore the association between tuberculosis (TB) and common mental disorders (CMD), in an area with high prevalence of TB.Methods: We performed a case-control study of TB patients and unmatched healthy controls, from a demographic surveillance site in Guinea-Bissau. Screening for CMD was performed once for controls and at inclusion and follow-up for TB patients. Kessler 10 (K-10) and a brief version of Hopkins Symptom Checklist 25 (SCL-8d) were used as screening instruments.Results: 571 controls were interviewed and 416 interviews were performed for 215 TB cases. Estimated CMD prevalence at the time of diagnosis of TB was 33.6 % (SCL-8d) and 46.2 % (K-10), compared with 6.8 % (SCL-8d) and 6.7 % (K-10) among controls; adjusted OR 7.18 (95 % CI 4.07 to 12.67) and 14.52 (95 % CI 8.15 to 25.84), respectively. No significant difference in CMD prevalence rates was observed between TB patients, after 6 months of treatment, and controls.Conclusion: Psychological distress and common mental disorders were more prevalent among TB patients at the time of diagnosis compared with the background population, but after completion of TB treatment no increased prevalence of psychological distress was found.