BACKGROUND: Latent Tuberculosis Infection (LTBI), a key driver of TB transmission, poses a significant challenge to India’s TB elimination goal by 2025. Treating LTBI is central to the National Strategic Plan to End TB, emphasizing the need to expand shorter Tuberculosis Preventive Treatment (TPT) regimens for high-risk groups. Tobacco users, with compromised immunity and an elevated risk of LTBI progression, remain under-prioritized. While WHO lacks systematic testing recommendations for tobacco users due to insufficient evidence, locally tailored strategies are essential. This systematic review and meta-analysis estimates LTBI prevalence among tobacco users in India to inform high-risk group prioritization and prevention policies.
METHODS: This review, conducted in accordance with PRISMA guidelines, performed a comprehensive literature search across Medline, Embase, CINAHL, and Scopus, focusing on studies reporting LTBI prevalence among tobacco users published up to March 2024, regardless of the diagnostic method employed. Data were pooled using a random-effects model to estimate prevalence, with heterogeneity assessed via Cochrane’s Q and I² statistics. The methodological quality of included studies was evaluated using the Joanna Briggs Institute appraisal tools.
RESULTS: From 10868 records, a total of 9 studies with 23283 individuals were included in the review. The pooled LTBI prevalence among tobacco users was 60% (95% CI: 54%-66%), compared to 31.3% in the general population. Males had a higher prevalence (65%) than females (50%), and rural populations (62%) slightly exceeded urban ones (58%). Prevalence was highest in individuals over 45 years, while younger groups (<30 years) had ~47%. Tobacco users with additional risk factors, like malnutrition and alcohol use, showed elevated prevalence (~70%). The pooled odds ratio of 1.8 (95% CI: 1.4–2.3) confirmed tobacco users were nearly twice as likely to have LTBI as non-users.
CONCLUSIONS: Our review revealed a high burden of LTBI among tobacco users, emphasizing the need to reprioritize this group for tailored TPT strategies.