Cystatin C as risk factor for cardiovascular events and all-cause mortality in the general population. The Tromsø Study.
BACKGROUND
Glomerular filtration rate<60 mL/min/1.73 m2 is associated with increased cardiovascular risk. Cystatin C is believed to be a better tool than creatinine for detection of mild renal dysfunction (>60 mL/min/1.73 m2) and possibly a more sensitive marker for cardiovascular risk and all-cause mortality. We examined the association of cystatin C with cardiovascular morbidity and all-cause mortality in a prospective population-based study.


METHODS
Cystatin C was measured in 2852 men and 3153 women in the Tromsø Study 1994/95. Gender-specific associations during 12 years of follow-up for all-cause mortality and 9.5 years for myocardial infarction (MI) and ischaemic stroke were assessed (Cox proportional hazard ratios, HRs).


RESULTS
During follow-up, 591 MIs, 293 ischaemic strokes and 1262 deaths occurred. In women, HR for all-cause mortality was increased in the upper cystatin C quartile (≥0.93 mg/L) compared with the lowest quartile (≤0.73 mg/L); 1.38, 95% confidence interval 1.04-1.84. A significant interaction with gender was observed. One SD (0.17 mg/L) increase in cystatin C was associated with 9% higher risk of death in women, also when persons with a cancer history were excluded. Crude HRs for MI and ischaemic stroke were increased in both genders, but the associations did not persist after multivariable adjustments. No independent associations with end points were observed in non-gender-specific analyses.


CONCLUSIONS
Cystatin C was not independently associated with fatal and non-fatal MI or ischaemic stroke in the general population. However, cystatin C was a risk factor for all-cause mortality in women.
Department of Nephrology, University Hospital of North Norway, and Department of Clinical Medicine, University of Tromsø, Tromsø, Norway. Ingrid.Toft@unn.no
Ingrid
I
Toft
Marit
M
Solbu
Jens
J
Kronborg
Ulla D
UD
Mathisen
Bjørn O
BO
Eriksen
Hilde
H
Storhaug
Toralf
T
Melsom
Maja-Lisa
ML
Løchen
Ellisiv B
EB
Mathiesen
Inger
I
Njølstad
Tom
T
Wilsgaard
Jan
J
Brox
D000368:Aged; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology* / Q000378:metabolism / Q000401:mortality*; D055316:Cystatin C / Q000378:metabolism*; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D015996:Survival Rate
C525030:CST3 protein, human; D055316:Cystatin C