Prevalence and predictors of decreased glomerular filtration rate in tibetan children with congenital heart disease.

OBJECTIVES

To assess the prevalence of decreased glomerular filtration rate (GFR) in Tibetan children with congenital heart disease (CHD) and its associated risk factors.

METHODS

A total of 207 Tibetan children attending authors' center for treatment of CHD from May 2012 through November 2012, were included in the study. GFR was estimated with the Schwartz formula (eGFR).

RESULTS

The mean eGFR was 104.3±16.6 mL/min/1.73 m2, and decreased in 21 children (10.1%). In the cyanotic category, eGFR was decreased only in severely cyanotic individuals. In the acyanotic category with left ventricular overload, children with decreased eGFR were younger, more commonly lived in areas above 4,700 m, and had higher left ventricular internal dimensions indexed by body surface areas (LVID/BSA) (53.8±6.9 vs. 40.1±6.8 mm/m2, P<0.001) compared with those with normal eGFR. Multivariate analysis identified LVID/BSA as the only independent predictor for decreased eGFR (OR: 1.329, 95% CI: 1.177~1.501, P<0.001). Receiver operating characteristic analysis showed the area under curve for LVID/BSA was 0.921 (95% CI: 0.863 ~ 0.980, P<0.001), with the optimal cutoff value of 49.8 mm/m2 (sensitivity: 75.0%, specificity: 93.9%). In the remaining category, decreased eGFR was only observed in those living above 4,700 m.

CONCLUSIONS

One tenth of Tibetan children with CHD had decreased eGFR. The risk factors included severe cyanosis, younger age, living above 4,700 m and higher LVID/BSA.