Predictors of rifampicin-resistant tuberculosis among infected patients in Nairobi County

Abstract

Background: Rifampicin-resistant tuberculosis (RR-TB) poses a significant threat to tuberculosis (TB) control in Kenya, particularly within Nairobi County, where it accounted for a 12% portion of new cases in 2019. The emergence of RR-TB strains has amplified the urgency of addressing this pressing public health crisis. Monitoring the risk factors for RR-TB to inform policy development and design effective interventions catering to the country's specific needs. Objectives: To determine sociodemographic, behavioural, and clinical factors associated with RR-TB among patients attending health facilities in Nairobi County. Methods: A case-control study for patients on TB treatment between January 2021 and March 2023 was conducted in Nairobi County. Data was collected using a free and open-source questionnaire for field data collection, KOBO application. Descriptive analysis was used to summarise participants' characteristics. Bivariate and multivariate logistic regression were used to determine the predictors for RR-TB. Associations were reported using Odds Ratio (OR) and 95% Confidence level (CI). Statistical significance was considered for p < 0.05. Results: 72 cases and 144 controls were enrolled; cases had a mean age of 38 years ±11 standard deviation (SD), while the control had a mean age of 36 years ±10 SD. Male gender contributed the highest proportion for both cases, 52 (72%) and controls 93 (65%). The odds of developing RRTB were 70 times higher among those patients who had a previous history of TB treatment compared to the new patients (aOR=69.909; p >0.001). Those who do not practice cough hygiene had five times increased odds of developing RRTB (aOR=5.265; p=0.002), and the co-infected TB/HIV patients had three times increased odds of developing RRTB (aOR=3.326; p=0.032). The odds of developing RRTB for those with chronic lung conditions were two times higher compared to those who did not have (aOR=1.682; p=0.778). The odds of developing RRTB for those who smoked cigarettes were two times more than those who did not smoke (aOR=1.512; p=0.463). Those admitted to hospitals had three times more odds of developing RRTB than those not admitted (aOR=2.982; p=0.139). No statistically significant differences were observed between age, gender, marital status, religion and the development of RRTB. Conclusion: Those patients who were previously treated for TB, those not practising cough hygiene, and those with HIV infection had a higher risk of developing RRTB. Recommendations There is a need for stronger partnerships between HIV and TB control programs in Nairobi County and Kenya in general to facilitate early detection and management of individuals with both diseases. This will effectively address the dual burden of HIV and TB.