The risk for chronic kidney disease in patients with heart diseases: a 7-year follow-up in a cohort study in Taiwan.

BACKGROUND

The worldwide increasing trend of chronic kidney disease (CKD) is of great concern and the role of heart disease deserves longitudinal studies. This study investigated the risk of developing CKD among patients with heart diseases.

METHODS

From universal insurance claims data in Taiwan, we retrospectively identified a cohort of 26005 patients with newly diagnosed heart diseases and 52010 people without such disease from the 2000-2001 claims. We observed prospectively both cohorts until the end of 2007 to measure CKD incidence rates in both cohorts and hazard ratios (HR) of CKD.

RESULTS

The incidence of CKD in the cohort with heart disease was 4.1 times greater than that in the comparison cohort (39.5 vs. 9.65 per 10,000 person-years). However, the HR changed into 2.37 (95% confidence interval (CI)=2.05-2.74) in the multivariate Cox proportional hazard model after controlling for sociodemographic characteristics and comorbidity. Compared with individuals aged<40 years, the HRs for CKD ranged from 2.70 to 4.99 in older age groups. Significant estimated relative risks of CKD observed in our patients were also independently associated with hypertension (HR=2.26, 95% CI=1.94-2.63) and diabetes mellitus (HR=2.44, 95% CI=2.13-2.80), but not with hyperlipidemia (HR=1.13, 95% CI=0.99-1.30).

CONCLUSIONS

This population study provides evidence that patients with heart disease are at an elevated risk of developing CKD. Hypertension and diabetes mellitus are also comorbidity associated with increasing the CKD risk independently.