Factors Associated with Tuberculosis in Kisii County: A Case Control Study

Abstract

Kenya is on track to attain two of the three global targets for reducing tuberculosis (TB); i.e. incidence and prevalence, while still has way to go in attaining the targets for mortality. While HIV remains an important driver of TB in Kenya, 67% of cases are not HIV related suggesting the need to identify and address other drivers of the epidemic. The objective of this study was to determine the association of TB with smoking, alcohol consumption, diabetes mellitus and malnutrition in Kisii County.This was an unmatched case control study in five facilities in Kisii County from September 2015 to January 2016. Cases were registered TB patients at the time of study, while controls were from the facility catchment areas. All prospective participants who tested HIV positive were excluded. The outcome of interest was TB infection and exposures were alcohol consumption, cigarette smoking, diabetes mellitus (RBS > 200 mg/ dL or FBS > 126 mg/ dL) and malnutrition (BMI<18.5 kg/ m2). Age (years), sex (male/female), household size (≤3 or >3) and education level (none, primary, secondary and college/university) were included as covariates. Data was collected on Open Data Kit (ODK)platform and analyzed using Stata 12®. Sample size of 268 was determined using Kelsey formula. Between September 2015 and January 2016, a total of 268 participants (77 cases, 191 controls) were enrolled into the study.Overall, malnutrition was associated with a higher likelihood of TB and this likelihood increased as other factors were adjusted for (AOR =16.68, 95% CI = 6.97 – 39.88). Diabetes was associated with six times higher odds of TB and the odds increased with adjusting for other covariates (AOR =6.30, 95% CI=1.94 – 20.48). Smoking and alcohol use were not significantly associated with increased likelihood of TB but the observed odds in both cases were attenuated after adjusting for other covariates.This study showed that diabetes is associated with a significantly higher chance of getting TB and that malnutrition was associated with the highest likelihood of having TB among all the exposures assessed. This study demonstrated the need to understand the relationship between NCDs, and their risk factors and diabetes in settings battling with a double burden of NCDs and communicable diseases.There is thus an urgent need to reconfigure our health systems to focus on tackling NCDs and the challenges they pose to public health