Urolithiasis is associated with an increased risk of stroke: a population-based 5-year follow-up study

Background: Epidemiological studies have reported an association between urolithiasis and cardiovascular disease. However, studies examining the risks of ischaemic and haemorrhagic stroke in patients with urolithiasis are limited. Aims and methods: By using a nationwide population database, we conducted a matched cohort study to investigate the association between urolithiasis and longitudinal risks of ischaemic and haemorrhagic stroke. Results: The urolithiasis and non-urolithiasis cohorts included 12 979 and 64 895 patients respectively. Of these, 728 (5.6%) and 2802 (4.3%) patients in the urolithiasis and non-urolithiasis cohorts, respectively, had a stroke during the 5-year follow-up period. The hazard ratio (HR) for stroke was 1.19 times higher (95% confidence interval [CI] = 1.10–1.29; P < 0.001) in the urolithiasis cohort than in the non-urolithiasis cohort after adjustment for potential confounders. The risk of both ischaemic (adjusted HR = 1.16; 95% CI = 1.05–1.29) and haemorrhagic stroke (adjusted HR = 1.30; 95% CI = 1.03–1.64) remained significant in the urolithiasis cohort. Furthermore, the risk of stroke was significant in both men (adjusted HR = 1.16; 95% CI = 1.05–1.28) and women (adjusted HR = 1.26; 95% CI = 1.10–1.45). Middle-aged (40–59 years; adjusted HR = 1.26; 95% CI = 1.10–1.45) and older (≥60 years; adjusted HR = 1.14; 95% CI = 1.03–1.27) patients had a particularly high risk of stroke. Conclusions: The present study detected an increased risk of both ischaemic and haemorrhagic stroke in patients with urolithiasis, particularly in those older than 40 years.