Behavioral Factors Associated With Tuberculosis Treatment Interruption Among Residents of Kiandutu Informal...

Background Tuberculosis (TB) treatment interruption remains a major barrier to successful TB control, contributing to poor treatment outcomes, ongoing transmission, and the emergence of drug-resistant TB. Although behavioral factors influence treatment adherence, evidence from informal settlements in Kenya remains limited. This study determined the prevalence of TB treatment interruption and examined behavioral factors associated with treatment interruption among patients receiving TB treatment in Kiandutu Informal Settlement, Kiambu County, Kenya. Methodology A convergent, cross-sectional, mixed-methods study was conducted between February 17, 2026, and May 17, 2026, among 292 adults receiving TB treatment at Thika Level 5 Hospital and Kiandutu Level 3 Hospital. Quantitative data were collected using structured questionnaires and patient records, while qualitative data were obtained through in-depth interviews with healthcare workers, community health workers, and community members. Quantitative data were analyzed using generalized linear models with a Poisson distribution, log link, and robust standard errors to estimate prevalence ratios (PRs) and 95% confidence intervals (CIs). Qualitative data were analyzed thematically, and findings were integrated during interpretation. Results The prevalence of TB treatment interruption was 23.3% (95% CI: 18.8%-28.5%). Alcohol consumption during treatment was the only behavioral factor independently associated with treatment interruption (adjusted PR = 2.00; 95% CI: 1.32-3.05). Tobacco smoking, illicit drug use, and treatment-related beliefs were not independently associated with treatment interruption. However, each one-unit increase in the cumulative behavioral risk score was associated with a 35% higher prevalence of treatment interruption (PR = 1.35; 95% CI: 1.11-1.64; p = 0.003). Qualitative findings complemented the quantitative results by identifying alcohol use, symptom-driven treatment cessation, poverty, stigma, and substance use as barriers to treatment adherence. Conclusions TB treatment interruption remains common among patients receiving care in Kiandutu Informal Settlement. Alcohol consumption was the principal behavioral factor associated with treatment interruption, while a greater cumulative burden of behavioral and treatment-related risk indicators was associated with a higher prevalence of interruption. Integrating alcohol screening, behavioral risk assessment, and continuous adherence counselling into TB care may help improve treatment completion in informal settlement settings.