Stroke epidemiology in Novosibirsk, Russia: a population-based study.

OBJECTIVE

To determine first-ever stroke incidence, 30-day case-fatality rates, and frequency of various risk factors among patients with stroke in Novosibirsk, Russia, during 1992.

DESIGN

A population-based study of an administratively defined district of Novosibirsk was conducted to identify residents with a first-ever stroke that occurred between Jan. 1, 1992, and Dec. 31, 1992.

MATERIAL AND METHODS

For case ascertainment, mortality statistics, death certificates, hospital registrations, outpatient clinical data, and all ambulance calls for the study area were reviewed. Patients with stroke or suspected stroke were examined and interviewed by a cerebrovascular neurologist, and the type of stroke was determined.

RESULTS

During the 12-month study period, 366 patients with first-ever stroke were registered. A diagnosis of cerebral infarction or intracerebral hemorrhage was confirmed by computed tomography or autopsy in 42% of cases. The diagnosis of subarachnoid hemorrhage was established by cerebrospinal fluid examination in all 14 cases. The age- and sex-adjusted annual incidence rate for stroke was 232 per 100,000. The distribution of incidence cases by diagnostic category was as follows: cerebral infarction, 87.7%; intracerebral hemorrhage, 8.5%; and subarachnoid hemorrhage, 3.8%. The overall 30-day case-fatality rate for stroke was 22.4%. Hypertension, angina pectoris, and cigarette smoking were the most frequent risk factors in patients with stroke in Novosibirsk.

CONCLUSION

The incidence rate of first-ever stroke in Novosibirsk, Russia, is one of the highest in the world, but the 30-day case-fatality rates are similar to those in other populations.