Kidney Week

Abstract: TH-PO681

Does CKD Predict Stroke Risk Independent of Blood Pressure? A Systematic Review and Meta-Regression

Session Information

• Hypertension and CVD: Epidemiology, Risk Factors
  November 07, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Hypertension and CVD

• 1401 Hypertension and CVD: Epidemiology, Risk Factors, and Prevention

Authors

• Kelly, Dearbhla, University of Oxford, Oxford, United Kingdom

Dearbhla Kelly,

• Rothwell, Peter M., University of Oxford, Oxford, United Kingdom

Peter M. Rothwell,

Background

Chronic kidney disease (CKD) appears to be an independent risk factor for stroke, with various purported mechanisms proposed. Low glomerular filtration rate (eGFR) is a risk factor for stroke independent of cardiovascular risk factors in epidemiological studies, but there has been no systematic assessment of the impact of more complete adjustment for blood pressure (BP) on the association.

Methods

We did a systematic review to February 2018 (MEDLINE/EMBASE) for cohort studies or randomized controlled trials that reported stroke incidence in adults according to baseline eGFR. Study and participant characteristics and relative risks (RR) were extracted. Estimates were combined using a random effects model. Heterogeneity was assessed by x² statistics and I², and by subgroup strata and meta-regression.

Results

We identified 168 studies reporting data on 5,611,939 participants with 115,770 stroke outcomes. 85 studies (3,417,098 participants; 72,996 strokes) provided adequate data for meta-analysis of eGFR and stroke risk. Incident stroke risk was increased among participants with eGFR <60 ml/min/1.73m2 (RR=1.73, 95% CI 1.57-1.90; p<0.001), but there was substantial heterogeneity between studies (p<0.0001; I2 - 78.5%). Moreover, the association was reduced after adjustment for cardiovascular risk factors, with progressive attenuation on more thorough adjustment for hypertension: single baseline BP measure (RR=1.63, 1.34-1.99; p<0.001); history or treated hypertension (RR=1.35, 1.24-1.46, p<0.001); multiple BP measurements over months to years (RR=1.10, 1.02-1.18; p=0.01).

Conclusion

The apparently independent relationship between CKD and stroke may be confounded by their shared association with long-term prior blood pressure, rendering other proposed mechanisms and related treatments unnecessary.