Helicobacter pylori infection: a risk factor for ischaemic cerebrovascular disease and carotid atheroma.

OBJECTIVES Chronic Helicobacter pylori infection has been associated with ischaemic heart disease although the mechanism by which it mediates this effect remains unclear. The objective was to determine whether it is also a risk factor for ischaemic cerebrovascular disease METHODS A total of 238 patients and 119 controls were studied. Patients were characterised into stroke subtypes based on pathogenic mechanisms and carotid atheroma load was estimated using duplex ultrasound. H pylori seropositivity was determined on serum samples. RESULTS H pylori seropositivity was more common in cases (58.8% v 44.5%, p=0.01). The odds ratio for cerebrovascular disease associated with seropositivity was 1.78 (95% confidence interval (95% CI) 1.14-2.77), and this remained significant after controlling for other risk factors including socioeconomic status (1.63 (95% CI 1.02-2.60). H pylori seropositivity was associated with large vessel disease (odds ratio 2.58 (95% CI 1.44-4.63), p=0.001) and lacunar stroke (odds ratio 2.21 (95% CI 1.12-4.38), p=0.02) but not stroke due to cardioembolism or unknown aetiology (odds ratio 1.16 (95% CI 0.66-2.02), p=0.5). Mean (SD) carotid stenosis was greater in patients seropositive for H pylori (37.3 (29.7) v 27.9 (26.2)%, p=0.01). There was no difference in the prevalence of seropositivity between patients with stroke and transient ischaemic attack (59.6% v 58.6%, p=0.9) CONCLUSION Chronic H pylori infection is an independent risk factor for ischaemic cerebrovascular disease and may act, at least in part, by increasing atherosclerosis.