Hu ZB, Lu ZX, Zhu F, et al. - This first cohort study of relatively healthy Chinese individuals in one of the most economically developed cities in China revealed an elevated risk of fatal all stroke occurrence in relation to white blood cell (WBC) count, especially the neutrophil (NEUT) count.

• This study included 27,811 participants followed up for a mean of 11.5 (standard deviation = 2.3) years, to clarify if the WBC count, its subpopulations and their dynamic alterations are linked with the risk of fatal stroke in relatively healthy elderly population.

• An atypically U-curved link between the WBC count and the risk of fatal all stroke occurrence was demonstrated by restricted cubic splines.

• A 53 and 67% elevated risk for fatal all stroke (adjusted hazard ratio [aHR] = 1.53) and fatal hemorrhagic stroke (aHR = 1.67), respectively, was noted in the highest WBC count (> 7.2*10^9/L) vs the lowest WBC count quartile (< 5.3*10^9/L).

• The highest NEUT count (> 4.5*10^9/L), vs the lowest quartile (< 3.0*10^9/L), was linked with a 45 and 65% elevated risk for fatal all stroke (aHR = 1.45) and fatal ischemic stroke (aHR = 1.65), respectively.

• In the elderly population, longitudinal alterations in the WBC count and NEUT count rise in excess of 25% were also related to an elevated risk of fatal all stroke occurrence.