Implementation Determinants of Integrated Tuberculosis and Diabetes Care in South Asian Association for Regional Cooperation (SAARC) Countries: A Systematic Review.

Tuberculosis (TB) and diabetes mellitus (DM) represent a growing syndemic in low- and middle-income countries (LMICs), particularly across South Asia. The bidirectional relationship between these diseases exacerbates health outcomes and increases system burdens. Although the World Health Organization has advocated for integrated management of TB and DM, implementation remains inconsistent across the SAARC region. This systematic review aims to identify and analyse implementation determinants of integrated TB and DM care in SAARC countries. We conducted a systematic review following PRISMA 2020 guidelines. searching MEDLINE (via Ovid), EMBASE, Web of Science, Cochrane CENTRAL, and CINAHL for peer-reviewed studies. Grey literature was sourced from Google Scholar and citation search. Four reviewers independently screened title, abstract and full text using Rayyan. Using a structured Excel form, two reviewers extracted data. Quality assessment was conducted by using Mixed Methods Appraisal Tool (MMAT). A narrative synthesis was conducted in line with SWiM guidelines to categorize implementation determinants as barriers or facilitators. Ten studies met the inclusion criteria and were conducted across five SAARC countries: India (n = 7), Pakistan (n = 1), Bangladesh (n = 1), and Sri Lanka (n = 1). Identified facilitators included political commitment, use of digital tools, and training of healthcare workers. Barriers encompassed inadequate infrastructure and finances, workforce shortages, lack of standardized guidelines and fragmented vertical health systems. Integrated TB-DM care in the SAARC region remains at an early developmental stage, with most efforts limited to pilot projects or small-scale screenings. Despite political and institutional recognition of the dual burden, scale-up is constrained by systemic barriers, resource gaps, and lack of evidence-informed implementation strategies. Future efforts should prioritize system-wide integration guided by implementation frameworks, standardized protocols, and investment in workforce and infrastructure to achieve sustainable impact. PROSPERO registration number: CRD42025644263.