Evolving spectrum and outcomes of infective endocarditis in North India: A comparative analysis between people who inject drugs and those who do not

BACKGROUND: Infective endocarditis (IE) data from South Asia remain limited, particularly among people who inject drugs (PWID). North India faces a growing injection drug burden, yet comparative IE data between PWID and non-PWID populations are scarce. METHODS: This retrospective cohort study with prospective long-term follow-up was conducted at a tertiary center in Ludhiana, Punjab, India. Patients meeting modified Duke criteria for definite IE (January 2017-December 2021) were compared between PWID (n = 62) and non-PWID (n = 101) groups. Multivariate logistic regression identified in-hospital mortality predictors. Five-year vital status was ascertained by telephone contact. RESULTS: PWID were younger (29.2 ± 7.5 vs. 45.0 ± 15.4 years, p = 0.001), predominantly male (98.4% vs. 64.4%), and had higher hepatitis C co-infection (54.8% vs. 5.9%). Blood culture positivity was greater in PWID (74.2% vs. 32.7%), with MRSA predominating (41.9% vs. 14.9%) and Pseudomonas as the second commonest PWID pathogen (16.1%). Tricuspid valve involvement dominated in PWID (71%), while mitral valve predominated in non-PWID (55.4%). In-hospital mortality was 22.7% with no between-group difference (p = 0.787). Septicemia (OR 5.25), left-sided valve involvement (OR 5.59), deranged liver function (OR 3.76), and congestive heart failure (OR 3.41) independently predicted mortality; PWID status did not. Among 92 contactable patients at five-year follow-up, cumulative mortality was 56.5%, without significant between-group difference (p = 0.33). CONCLUSIONS: IE in North India affects younger patients than Western cohorts. PWID-IE in North India shows distinct features including MRSA dominance and higher culture positivity, yet in-hospital and long-term mortality remain comparable between groups. High culture-negative rates and low surgical intervention warrant attention.