Cystatin C is associated with risk of venous thromboembolism in subjects with normal kidney function--the Tromsø study.

Abstract

BACKGROUND:

Previous studies have shown an association between impaired kidney function, assessed by cystatin C-based estimated glomerular filtration rate, and venous thromboembolism. The aim of this study was to investigate whether serum cystatin C was associated with a risk of venous thromboembolism among subjects with normal kidney function in a prospective population-based study.

DESIGN AND METHODS:

Cystatin C was measured in serum from 3251 men and women with normal kidney function, aged 25-84 years, who participated in the Tromsø study in 1994-1995. Normal kidney function was defined as a creatinine-based estimated glomerular filtration rate greater than 90 mL/min/1.73 m(2) and absence of microalbuminuria. Incident venous thromboembolism was registered from the date of inclusion through to the end of follow-up, September 1, 2007. Cox-regression models were used to calculate hazard ratios with 95% confidence intervals for venous thromboembolism.

RESULTS:

There were 83 incident venous thromboembolic events, of which 53 (63.9 %) were provoked, during a median of 12.3 years of follow-up. A one standard deviation (0.11 mg/L) increase in serum cystatin C levels was associated with a 43% (hazard ratio 1.43; 95% confidence interval 1.17-1.72) increased risk of total venous thromboembolism. Subjects with cystatin C levels in the top quartile (≥ 0.87 mg/L) had a 2.5-fold (hazard ratio 2.51; 95% confidence interval 1.27-4.96) increased risk of venous thromboembolism compared to those with levels in the bottom quartile (≤ 0.72 mg/L) in adjusted analysis. The risk estimates were even higher for provoked venous thromboembolism (hazard ratio 3.11; 95% confidence interval 1.23-7.86).

CONCLUSIONS:

Serum cystatin C levels were associated with the risk of venous thromboembolism in subjects with normal kidney function. Our findings suggest that elevated serum cystatin C levels may promote venous thrombosis beyond reflecting impaired kidney function.

• Authors: Ellen E Brodin, Sigrid K Brækkan, Anders Vik, Jan Brox, John-Bjarne Hansen
• Journal: Haematologica (Haematologica) Vol. 97 Issue 7 Pg. 1008-13 (Jul 2012) ISSN: 1592-8721 [Electronic] Italy
• PMID: 22315498 (Publication Type: Journal Article)

Chemical References

• Biomarkers
• Cystatin C
• Creatinine

Topics

• Adult
• Aged
• Aged, 80 and over
• Biomarkers (blood)
• Creatinine (urine)
• Cystatin C (blood)
• Female
• Glomerular Filtration Rate
• Humans
• Kidney (metabolism, physiopathology)
• Male
• Middle Aged
• Prognosis
• Proportional Hazards Models
• Prospective Studies
• Risk
• Venous Thromboembolism (blood, diagnosis, physiopathology)