Prevalence and predictors of diabetes mellitus among tuberculosis patients in india: a systematic review and meta-analysis

Diabetes Mellitus (DM) and Tuberculosis (TB) are both highly prevalent in India, and the combination of both has emerged as a syndemic in the country. Accordingly, the aim was to estimate the pooled prevalence of DM among TB patients in India and identify its predictors. A systematic review and meta-analysis was conducted, and the data were extracted until 6th May 2025, utilising three databases: PubMed, EMBASE, and Scopus. A total of 22 articles were included in the review, and they underwent quality assessment using the Newcastle-Ottawa Scale (NOS), the Modified-NOS, and the National Institute of Health (NIH) quality assessment tool. The pooled prevalence of DM among TB patients was estimated with a 95% Confidence Interval (CI), assuming potential heterogeneity, as determined by a random-effects model. The predictors were analysed quantitatively, and the pooled adjusted odds ratios (AOR) were estimated. A total of 67,155 individuals were included, ranging from 31 in Maharashtra to 47,831 in Odisha. The pooled prevalence of DM in TB patients was 20% (95% CI: 15%-27%), with the highest prevalence of 30% (95% CI: 17%-45%) observed in Pulmonary-TB cases, compared to all TB cases (18%, 95% CI: 12%-24%). Substantial heterogeneity was observed across the included studies, with I 2 = 99.44%, z = 11.80, p < 0.001, suggesting cautious interpretation of the pooled estimate. The predictors reported by the included studies were categorised into seven broad themes. For the male gender, the pooled AOR was 1.35 (95% CI: 0.91–2.01); for advancing age > 40 years, it was statistically significant at p < 0.001, with a pooled AOR of 5.09 (95% CI: 2.97–8.72); for alcoholism, the pooled AOR was 2.33 (95% CI: 0.68–7.96); for smoking, it was 1.10 (95% CI: 0.67–1.81). The pooled AOR for Pulmonary-TB was 1.84 (95% CI: 1.36–2.49) and was statistically significant at p < 0.001. The study estimated that one in every fifth TB patient is Diabetic in India, with regional variations; however, substantial heterogeneity suggests cautious interpretation of the pooled estimate. Bidirectional screening and integrated disease management must be mandated at all levels of healthcare to manage this syndemic.