Incidence of intracerebral hemorrhage in Shangdong province, East China, 2012-2021: a population-based study

Intracerebral hemorrhage (ICH) incidence is poorly documented in Asia, where it is highest globally. We examined ICH incidence in Shandong Province, East China, using a population-based stroke surveillance system established in 2012, aiming to inform ICH prevention in East China. We obtained the ICH data from Shandong Province in eastern China, covering a period of ten years from 2012 to 2021. Crude, age-standardized, age-specific, gender-specific, and region-specific incidence were calculated.Seasonal trend was assessed and Joinpoint regression was used to compute the Annual Percent Change (APC) in incidence.The life table method was used to estimate ICH early onset probability among residents aged 30-54 years. Spatial autocorrelation analysis was used to identify ICH hot spots. A total of 96,978 cases of ICH were reported. Crude ICH incidence rose from 57.96 to 76.54 per 100,000 (2012 - 2018; APC=4.48%[95%CI:2.66-6.32], P < 0.001), then dropped nonsignificantly to 69.14 (2018 - 2021; APC=- 2.61%[-7.53-2.57], P = 0.250). Males, rural areas, and those ≥45 years old had higher incidence. The probability of early onset (aged 30 - 54 years) increased from 0.75% to 1.11% (2012 - 2018; APC=6.36%[2.24-10.65], P=0.010), then decreased nonsignificantly. Significant seasonal variation was confirmed (P<0.001), with peak observed in January (accounting for 10.86% of all cases) and trough in July (accounting for 6.62% of all cases). We also found ICH hot spots in northern (Liaocheng, Dezhou, Binzhou), western (Heze), and southern (Linyi) regions of Shandong Province in 2021. Over 10 years, ICH incidence in Shandong Province shifted from increasing to stable and was more higher in males, rural areas, and those ≥45 years old, with seasonal peaks in winter. The identification of spatial clusters in specific regions underscored the need of targeted prevention strategies.