Glomerular filtration rate in patients with Cushing's disease: a matched case-control study.

BACKGROUND

Patients with Cushing's disease have a high prevalence of atherosclerosis and maintain an increased cardiovascular risk even after cure of the disease. However, the impact of Cushing's disease on renal function remains to be quantified.

OBJECTIVES

To evaluate glomerular filtration rate (GFR) and to identify predictors of GFR in patients with Cushing's disease.

DESIGN AND

METHODS

We conducted a matched case-control study: 18 patients with active or cured Cushing's disease were compared with healthy population controls matched for age and sex. The main outcome measures were GFR and micro-albuminuria.

RESULTS

Patients with Cushing's disease had a lower GFR, as measured by 24-h creatinine clearance (79 versus 95 ml/min per 1.73 m2, P = 0.005) and estimated by the MDRD2 formula (75 versus 88 ml/min per 1.73 m2, P = 0.008). Multiple regression analyses indicated that disease duration was the strongest predictor for a worse GFR. The prevalence of micro-albuminuria was low (5.5% in both groups).

CONCLUSIONS

Patients with Cushing's disease have a decreased GFR. Even if they are cured, close follow-up with strict control of cardiovascular risk factors and monitoring of GFR seems mandatory. Furthermore, the dosage of certain drugs should be adapted to the individual GFR.