Stroke epidemiology in Siberia

Based on WHO MONICA methods and diagnostic criteria, it is shown that first -ever stroke incidence and mortality in Siberia (a total number of resident s included in the analysis varied from 450 000 to about 800 000) that are a mong the highest in the world. In Novosibirsk, for the period from 1982 thr ough 1991 there was a trend towards decreasing stroke incidence and mortali ty rates, but for the period from 1992 through 1997 there was a trend towar ds increasing there rates in both men and women. Age-standardized (US white population was used as a standard) stroke incidence rates increased from w est to east and from south to north across Siberia, with a corresponding in crease in the proportion of hemorrhagic strokes. In 1987-1988, age-adjusted stroke incidence rate in Novosibirsk was 212 per 100 000 residents per yea r, in Krasnoyarsk - 325, in Tynda - 329, in Anadyr - 348. Stroke-case fatal ity rates ranged from 28% in Tynda to 41% in Anadyr. A multivariate regress ion analysis revealed that hypertension, left ventricular hypertrophy, isch emic heart disease. mitral valve disease, current cigarette smoking, excess ing body mass index, winter season, and low ambient temperature are all sig nificant and independent risk factors for the occurrence of ischemic stroke in Novosibirsk. A significant association between stroke occurrence and ai r pressure/geomagnetic activity change was found. Possible reasons for such unfavorable trends in stroke incidence in Siberia are discussed, and an op timal approach for improving organization of cerebrovascular disease care i s suggested.