Navigating the HIV/AIDS epidemic in Bangladesh: A comprehensive retrospective analysis of epidemiological trends and sex-specific disparities (1990-2021) with long-term ARIMA forecasting to 2050 for strategic public health planning.

Background: The HIV/AIDS epidemic remains a critical public health challenge in Bangladesh, with complex epidemiological trends and sex-specific disparities requiring detailed investigation to guide effective interventions. This study comprehensively analyzes the temporal dynamics of HIV/AIDS burden from 1990 to 2021 and employs advanced statistical modeling to forecast future trends up to 2050, aiming to inform targeted public health strategies. Methods: Data on Disability-Adjusted Life Years (DALYs), deaths, incidence, prevalence, Years Lived with Disability (YLDs), and Years of Life Lost (YLLs) were sourced from a robust epidemiological database for Bangladesh. Joinpoint regression analysis was utilized to detect significant trend changes, calculating the average annual percent change (AAPC) and annual percent change (APC) with 95 % confidence intervals (CIs). Sex-stratified analyses elucidated disparities between males and females. Autoregressive Integrated Moving Average (ARIMA) models were applied to project age-standardized rates (ASRs) for each metric through 2050, incorporating historical trends and variability to ensure robust predictions. Results: From 1990 to 2021, the HIV/AIDS burden in Bangladesh increased significantly across all metrics, with distinct sex-specific patterns. The overall AAPC for DALYs was 19.0332 % (95 % CI: 15.8145, 23.0026, p < 0.000001), with females showing a higher AAPC (21.7252 %, 95 % CI: 18.2308, 25.7026) than males (18.4703 %, 95 % CI: 15.1896, 22.5646). Deaths exhibited a similar trend, with an overall AAPC of 18.9645 % (95 % CI: 15.7008, 23.2166), higher in females (21.8808 %, 95 % CI: 18.4195, 25.9932) than males (18.4655 %, 95 % CI: 15.1992, 22.6832). Incidence rose with an AAPC of 15.7929 % (95 % CI: 11.6467, 19.1922), slightly higher in females (16.2581 %, 95 % CI: 12.1795, 20.0487) than males (15.1639 %, 95 % CI: 11.2952, 18.4817). Prevalence increased markedly (AAPC: 18.2239 %, 95 % CI: 14.5688, 22.2078), with females at 20.2887 % (95 % CI: 16.6453, 24.3006) and males at 18.1837 % (95 % CI: 14.6734, 21.841). YLDs and YLLs followed similar patterns, with females consistently showing higher AAPCs. Joinpoint analysis identified peak APCs in the 1990s and early 2000s, followed by moderated growth and declines post-2016, particularly from 2019 to 2021, reflecting potential intervention impacts. ARIMA forecasts project a decline in DALYs, deaths, and YLLs ASRs to negligible levels by 2050 for both sexes, with wide CIs indicating substantial uncertainty (e.g., DALYs overall: negligible, 95 % CI: 0, 583.3697). Incidence ASRs are expected to stabilize (e.g., overall: 0.963899, 95 % CI: 0, 3.819279), while prevalence ASRs are projected to rise dramatically, particularly for males (614.7463, 95 % CI: 0, 695680.4), highlighting significant long-term challenges. Conclusions: The HIV/AIDS burden in Bangladesh has escalated significantly from 1990 to 2021, with females bearing a disproportionately higher burden across all metrics. Recent declines suggest the efficacy of public health interventions, but persistent sex disparities and projected prevalence increases underscore the need for targeted, sex-specific strategies. The considerable uncertainty in long-term forecasts emphasizes the importance of sustained surveillance, adaptive interventions, and resource allocation to mitigate the epidemic's impact by 2050, ensuring equitable health outcomes.