Effect of Tuberculosis (TB) and Diabetes mellitus (DM) integrated healthcare on bidirectional screening and treatment outcomes among TB patients and people living with DM in developing countries: a systematic review.

A systematic review (Prospero CRD42017075562) including articles published between 1 January 1990 and 31 October 2021 was performed to synthesize evidence on the effect of integrating tuberculosis (TB) and diabetes mellitus (DM) healthcare on screening coverage and treatment loss to follow-up as compared to non-integrated care services for TB and DM in low- to middle-income countries (LMICs). Searches were performed in PubMed, Web of Science, WHO Global Index Medicus, and Cochrane Central Library. This review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and we adopted Cochrane data collection form for Randomized Controlled Trials (RCTs) and non-RCTs. Due to heterogeneity and limited data of studies included, meta-analysis was not performed. Of 6902 abstracts, 10 studies from South America, Asia, and Africa were included. One study from Zimbabwe showed 57% increase in DM screening among TB patients in integrated care as compared to non-integrated care; 95% CI: 54.1, 59.8. Seven studies with before-after comparison groups reported increased screening coverage during implementation of integrated healthcare that ranged from 10.1% in Mexico to 99.1% in China. Three studies reported reduction in loss to follow-up among TB patients in integrated care; two in China showed 9.2%, 95% CI: -16.7, -1.7, and -9.5%, 95% CI: -18.4, -0.7 differences, while a study from Mexico showed -5.3% reduction, 95% CI: -9.8, -0.9.With few and heterogenous included studies, the synthesized evidence is weak to establish effect of TB/DM integrated care. Therefore, further robust studies such as randomized clinical trials and well-designed observational studies are needed.