International Journal of Drug Delivery Technology · Apr 29, 2026
Predictive Biomarkers for Mortality Risk Assessment in Geriatric Individuals Following COVID-19 Booster Vaccination: A District-Level Study from Assam, India
By Islam S, Nath B, Debnath S et al.
Cardiovascular and respiratory diseases remain major contributors to morbidity and mortality among elderly individuals due to age-related physiological decline, multimorbidity, and reduced immune responsiveness. Although COVID-19 booster vaccination has demonstrated a favorable safety profile globally, evidence regarding biomarker-based assessment of post-vaccination cardiopulmonary outcomes among geriatric populations in Northeast India remains limited. The present prospective cohort study evaluated predictive biomarkers associated with cardiovascular and respiratory events following COVID-19 booster vaccination among elderly individuals in selected districts of Assam, including Dhubri, Goalpara, Barpeta, and Bongaigaon. A total of 400 participants aged ≥60 years were followed for 12 months using active telephonic surveillance and verification through hospital records to identify incident clinical events. Organ-specific biomarkers, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), C-reactive protein (CRP), peripheral oxygen saturation (SpO₂), serum creatinine, and blood urea nitrogen (BUN), were assessed at baseline and follow-up to evaluate physiological responses after vaccination. During the follow-up period, 24 cardiovascular events and 32 respiratory events were recorded, corresponding to cumulative incidences of 6% and 8%, respectively, with higher event rates observed among participants aged ≥71 years and those with pre-existing comorbidities. Mild but statistically significant elevations in hepatic enzymes and CRP levels were observed; however, these remained within normal clinical limits. No significant changes were detected in renal function markers or oxygen saturation levels. Overall, the findings indicate that COVID-19 booster vaccination was well tolerated among geriatric individuals. Biomarker-guided monitoring may facilitate early identification of high-risk individuals and support evidence-based post-vaccination surveillance strategies in resource-limited regional healthcare settings such as Northeast India.