Excess mortality and cardiovascular events in patients surviving subarachnoid hemorrhage: A nationwide study in Sweden

Background and Purpose: Survivors of aneurysmal subarachnoid hemorrhage (SAH) may have an increased risk of cardiovascular events because of shared risk factors. We compared incidences of vascular diseases, vascular death, and all-cause death after SAH with those in the general population.

Methods: From the Swedish Hospital Discharge and Cause of Death registries, we identified patients with SAH between January 1987 and January 2003. Conditional on survival of 3 months after SAH, we calculated standardized mortality and incidence ratios with corresponding 95% CIs for vascular death, all-cause death, and fatal or nonfatal vascular diseases. Cumulative risks were estimated with survival analysis.

Results: Of 17 705 patients with SAH (mean age, 59.7 years; 59.5% women), 11 374 survived at least 3 months after SAH. During follow-up (mean, 6.8 years), 2152 (18.9%) died. The risk of death was 12.9% within 5 years, 23.6% within 10 years, and 35.4% within 15 years after SAH. The overall standardized mortality ratio was 1.57 (95% CI, 1.44 to 1.70) for vascular death and 1.61 (95% CI, 1.52 to 1.70) for all-cause death. The standardized mortality ratios were particularly high in younger individuals, ranging from 2.1 to 3.7 for vascular death and from 2.1 to 2.6 for all-cause death for patients between 50 and 65 years of age. The standardized incidence ratio for fatal or nonfatal vascular diseases was 1.51 (95% CI, 1.45 to 1.56).

Conclusions: Mortality and risk of vascular diseases are increased in survivors of SAH. Prevention of new vascular diseases after SAH by management of risk factors seems important.