Epidemiological trends in colorectal cancer mortality in South Asia, 1990–2023: A retrospective analysis and advanced machine learning forecasting to 2050.

Abstract

e15591 Background: Colorectal cancer (CRC) is an emerging cause of cancer mortality in South Asia, yet comprehensive long-term trend analyses incorporating sex-specific patterns and future projections are limited. We evaluated historical CRC mortality trends and forecasted future burden across South Asia from 1990 to 2050. Methods: We conducted a retrospective population-based analysis of age-standardized mortality rates (ASMRs) for CRC across South Asia between 1990 and 2023, from the Global Burden of Disease 2023 database, stratified by country and sex. Temporal trends were quantified using estimated annual percentage change (EAPC) with 95% confidence intervals (CIs). Machine learning–based ARIMA time-series models were applied to project ASMRs through 2050 with uncertainty intervals. Results: From 1990–2023, CRC mortality increased significantly across South Asia (both sexes EAPC 0.60; 95% CI 0.47–0.73), with higher growth among males (EAPC 0.78; 95% CI 0.65–0.91) than females (0.43; 95% CI 0.27–0.58). Pakistan showed the steepest increase (both sexes EAPC 1.12; 95% CI 1.01–1.23), followed by Bangladesh (1.00; 0.80–1.21), India (0.49; 0.36–0.63), and Bhutan (0.44; 0.35–0.53). Nepal demonstrated near-stable trends (both sexes EAPC 0.06; −0.16 to 0.29), with declining female mortality (−0.20; −0.45 to 0.05). In Pakistan, male ASMRs rose from 3.79 (1990) to 5.37 per 100,000 (2023) and are projected to reach 6.64 (95% UI 5.21–8.07) by 2050; female ASMRs increased from 6.61 to 8.76 and are forecast to reach 10.51 (8.65–12.37). In Bangladesh, both-sex ASMRs increased from 4.61 (1990) to 7.59 (2023) and are projected to nearly double by 2050 (14.92; 6.14–23.70), driven by rapid rises among females. India showed moderate increases, with male ASMRs stabilizing after 2023 (~5.55), while female ASMRs rose from 4.12 to 4.88 and are projected to plateau near 4.9–5.0 after 2030. Conclusions: CRC mortality has risen steadily across South Asia over the past three decades, with marked male predominance and substantial inter-country heterogeneity. Forecasts indicate a sustained and disproportionate future burden in Pakistan and Bangladesh, underscoring the urgent need for population-level screening, early detection strategies, and equitable access to oncologic care. Location Sex EAPC Lower 95%CI Upper 95%CI Bangladesh Both 1.00 0.80 1.21 Bangladesh Female 0.56 0.27 0.86 Bangladesh Male 1.36 1.22 1.51 Bhutan Both 0.44 0.35 0.53 Bhutan Female 0.26 0.14 0.39 Bhutan Male 0.64 0.58 0.70 India Both 0.49 0.36 0.63 India Female 0.34 0.18 0.50 India Male 0.67 0.52 0.82 Nepal Both 0.06 -0.16 0.29 Nepal Female -0.20 -0.45 0.05 Nepal Male 0.33 0.12 0.53 Pakistan Both 1.12 1.01 1.23 Pakistan Female 1.02 0.90 1.15 Pakistan Male 1.12 1.00 1.25 South Asia Both 0.60 0.47 0.73 South Asia Female 0.43 0.27 0.58 South Asia Male 0.78 0.65 0.91