Interaction between inflammation and blood viscosity predicts cardiovascular mortality.
OBJECTIVE
Inflammation and increased blood viscosity are associated with increased risk of cardiovascular mortality. Erythrocyte sedimentation rate (ESR) and hematocrit both influence blood viscosity whereas the first also is a marker of inflammation. We aimed to investigate ESR, hematocrit and the interaction between them as predictors of cardiovascular mortality during 26 years follow-up among healthy middle aged men.


METHODS
Four hundred and eighty eight men aged 40-59 were extensively examined in 1972-1975 and followed over a period of 26 years. Risk estimation was made in Cox proportional hazards and adjusted for age, smoking, systolic blood pressure, total serum cholesterol, and physical fitness.


RESULTS
A 2.44-fold (95% CI 1.37-4.35) adjusted risk of cardiovascular mortality was found in the highest quartile of hematocrit compared to the lowest. Among the 265 men who had an ESR <6 mm/h (median), the adjusted risk of cardiovascular mortality was 3.05-fold (95% CI 1.49-6.23) in the highest quartile of hematocrit compared to the lowest. This association was not observed among the 223 men with ESR <6 mm/h.


CONCLUSIONS
Elevated hematocrit is independently associated with increased long-term risk of cardiovascular mortality in men with high ESR. Our data suggest that the combination of inflammation and blood viscosity may improve the prediction of cardiovascular risk.
Skretteberg
Per Torger
PT
Department of Cardiology, Oslo University Hospital, Ullevaal, Oslo, Norway. torger.skretteberg@gmail.com
Bodegård
Johan
J
Kjeldsen
Sverre E
SE
Erikssen
Gunnar
G
Thaulow
Erik
E
Sandvik
Leif
L
Erikssen
Jan E
JE
D000328:Adult; D001799:Blood Sedimentation; D001809:Blood Viscosity; D002318:Cardiovascular Diseases / Q000097:blood* / Q000209:etiology / Q000401:mortality*; D005500:Follow-Up Studies; D006400:Hematocrit; D006801:Humans; D007249:Inflammation / Q000097:blood* / Q000150:complications / Q000401:mortality*; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors