Higher total serum cholesterol levels are associated with less severe strokes and lower all-cause mortality: ten-year follow-up of ischemic strokes in the Copenhagen Stroke Study.
OBJECTIVE
Evidence of a causal relation between serum cholesterol and stroke is inconsistent. We investigated the relation between total serum cholesterol and both stroke severity and poststroke mortality to test the hypothesis that hypercholesterolemia is primarily associated with minor stroke.


METHODS
In the study, 652 unselected patients with ischemic stroke arrived at the hospital within 24 hours of stroke onset. A measure of total serum cholesterol was obtained in 513 (79%) within the 24-hour time window. Stroke severity was measured with the Scandinavian Stroke Scale (0=worst, 58=best); a full cardiovascular risk profile was established for all. Death within 10 years after stroke onset was obtained from the Danish Registry of Persons.


RESULTS
Mean+/-SD age of the 513 patients was 75+/-10 years, 54% were women, and the mean+/-SD Scandinavian Stroke Scale score was 39+/-17. Serum cholesterol was inversely and almost linearly related to stroke severity: an increase of 1 mmol/L in total serum cholesterol resulted in an increase in the Scandinavian Stroke Scale score of 1.32 (95% CI, 0.28 to 2.36, P=0.013), meaning that higher cholesterol levels are associated with less severe strokes. A survival analysis revealed an inverse linear relation between serum cholesterol and mortality, meaning that an increase of 1 mmol/L in cholesterol results in a hazard ratio of 0.89 (95% CI, 0.82 to 0.97, P=0.01).


CONCLUSIONS
The results of our study support the hypothesis that a higher cholesterol level favors development of minor strokes. Because of selection, therefore, major strokes are more often seen in patients with lower cholesterol levels. Poststroke mortality, therefore, is inversely related to cholesterol.
Olsen
Tom Skyhøj
TS
Stroke Unit, Department of Neurorehabilitation, Hvidovre University Hospital, Kettegaard Allé 30, DK-2650 Hvidovre, Denmark. Tom.Skyhoej.Olsen@hvh.regionh.dk
Christensen
Rune Haubo Bojesen
RH
Kammersgaard
Lars Peter
LP
Andersen
Klaus Kaae
KK
D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002545:Brain Ischemia / Q000097:blood / Q000401:mortality; D002423:Cause of Death; D002784:Cholesterol / Q000097:blood*; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood* / Q000401:mortality*; D016014:Linear Models; D008297:Male; D011379:Prognosis; D012189:Retrospective Studies; D012720:Severity of Illness Index; D020521:Stroke / Q000097:blood* / Q000401:mortality*
D015415:Biomarkers; D002784:Cholesterol