Epidemiology and Risk Factors of Delayed Sputum Smear Conversion in Malaysian Aborigines with Smear-Positive Pulmonary Tuberculosis

Background: Tuberculosis (TB) remains a serious public health challenge despite enormous eradication efforts. Indigenous groups worldwide have a higher TB incidence and associated delayed sputum-smear conversion. The aim of this case-control study was to determine the epidemiology and factors associated with delayed sputum-smear conversion among Malaysian aborigines.

Methods: We used secondary data from 2016 to 2020 in the MyTB surveillance system. Malaysian aborigines with smear-positive pulmonary TB were enrolled and followed until the end of the intensive phase. Descriptive statistics and multiple logistic regression were used for data analysis.

Results: Of 725 Malaysian aborigines with pulmonary TB, 572 (78.9%) were smear-positive and 487 (78.9%) fulfilled the study criteria. The mean (SD) age of smear-positive pulmonary TB was 39.20 (16.33) years. Majority of participants were male (63%), Senoi tribe (54.9%), living in rural areas (88.1%), formally educated (60.4%) and living below the poverty line (97.1%). Overall, 93 (19.1%) of 487 patients showed delayed sputum-smear conversion and significantly associated factors, such as smoking (AdjOR: 3.25; 95% CI: 1.88, 5.59), diabetes mellitus (AdjOR: 12.84; 95% CI: 6.33, 26.06), and HIV infection (AdjOR: 9.76; 95% CI: 3.01, 31.65).

Conclusions: Stakeholders should adopt targeted approaches to tackle the problem of aboriginal groups with pulmonary TB and these associated risk factors to realise the End TB target.