Hypertension and clusters of risk factors in different stroke subtypes (an analysis of Hungarian patients via Budapest Stroke Data Bank)

Airborne pollutants and lacunar stroke: a case cross-over analysis on stroke unit admissions

Particulate air pollution is known to be associated with cardiovascular disease. The relation of particulate air pollution with cerebrovascular disease (CVD) has not been extensively studied, particularly in relation to different subtypes of stroke. A time-series study was conducted to evaluate the association between daily air pollution and acute stroke unit hospitalizations in Mantua, Italy. We analyzed 781 CVD consecutive patients living in Mantua county admitted between 2006-08. Data on stroke types, demographic variables, risk factors were available from the Lombardia Stroke Registry. Daily mean value of particulate matter with a diameter <10 µm (PM(10)), carbon monoxide, nitric oxide, nitrogen dioxide, sulphur dioxide, benzene and ozone were used in the analysis. The association between CVD, ischemic strokes subtypes and pollutants was investigated with a case-crossover design, using conditional logistic regression analysis, adjusting for temperature, humidity, barometric pressure and holidays. Among the 781 subjects admitted 75.7% had ischemic stroke, 11.7% haemorrhagic stroke 12.6% transient ischemic attack. In men admission for stroke was associated with PM(10) [odds ratio (OR) 1.01, 95%; confidence interval (CI) 1.00-1.02; P<0.05]. According to the clinical classification, lacunar anterior circulation syndrome stroke type was related to PM(10) level registered on the day of admission for both genders (OR: 1.01, 95%; CI: 1.00-1.02; P<0.05) while for total anterior circulation syndrome stroke only in men (OR: 1.04, 95%; CI 1.01-1.07; P<0.05).In conclusion, our study confirms that air pollution peaks may contribute to increase the risk of hospitalization for stroke and particulate matter seems to be a significant risk factor, especially for lacunar stroke.

Clustering of vascular risk factors and in-hospital death after acute ischemic stroke

OBJECTIVE

to evaluate the influence of clustering of vascular risk factors (VRF) on in-hospital mortality in patients with acute ischemic stroke (AIS) developing a risk score for mortality prediction.

METHODS

clinical data from 1527 patients admitted to hospital with a first-ever AIS were prospectively evaluated from 1997 to 2005 assessing the presence of six VRF: diabetes, hypertension, hyperlipidemia, ischemic heart disease, atrial fibrillation and peripheral arterial disease. A composite vascular risk score (VRS) was created using five risk factors. Hyperlipidemia was excluded from the score due to its protective impact on mortality. Two modified VRS models were created and assessed for their accuracy as predictors for in-hospital mortality based on the odds ratio for each VRF obtained in the univariate analysis.

RESULTS

197 patients (12.9 %) died during the acute hospitalization period. Stroke severity increased with each additional VRF (p = 0.002). Cox proportional hazards model adjusted for confounders showed an association between the composite VRS and in-hospital mortality (p = 0.045). According to the clustering of VRS, the risk for in-hospital death increased from 1.951 (95 % CI 1.041-3.665) for patients having one VRS to 2.343 (95% CI 1.081-5.076) for those having a VRS > or = 4. ROC curves showed that the modified VRS model based on a given value of one for each accumulated VRF, including the absence of hyperlipidemia, had the highest predictive capability for in-hospital mortality (p < 0.0001).

CONCLUSIONS

the presence of multiple VRF in patients with acute ischemic stroke increases the stroke severity and the risk of in-hospital death.