The impact of type II diabetes mellitus in patients with autosomal dominant polycystic kidney disease

Abstract

Background: The epidemic of obesity and diabetes is increasing within the USA and worldwide. We have previously shown that body mass index has increased significantly in autosomal dominant polycystic kidney disease (ADPKD) subjects seen at our center in more recent years. However, the impact of Type II diabetes in ADPKD patients has not been well studied.

Methods: This retrospective cohort study compared clinical characteristics in 44 pre-renal transplant patients with ADPKD and diabetes and 88 age- and sex-matched non-diabetic patients with ADPKD who were seen at the University of Colorado between 1977 and 2008. The primary outcomes in this study were renal volume determined by renal ultrasonography, renal function assessed by estimated glomerular filtration rate and time to onset of end-stage renal disease or death by Kaplan-Meier analyses.

Results: Diabetic patients had significantly larger kidney volumes than those with ADPKD alone [geometric mean (95% confidence interval (CI)]: 2456 (1510-3992) versus 1358 (1186-1556) cm3, P=0.02. Among those whose age at hypertension diagnosis was known, the diabetic ADPKD patients had earlier median (95% CI) age at onset of hypertension compared to those with ADPKD alone: 32.5 (28-40) versus 38 (35-42) years, P=0.04. Diabetic ADPKD patients tended to have an earlier median age of death than those with ADPKD alone.

Conclusions: Patients with ADPKD and type II diabetes have larger renal volumes, earlier age at diagnosis of hypertension and may die at a younger age compared to those patients with ADPKD alone. This study emphasizes the importance of diabetes risk management in ADPKD.

Fig. 1.

Time to diagnosis of hypertension. From left of Figure, dashed line represents ADPKD with diabetes and solid line represents ADPKD no diabetes. Open circles represent censored values in Kaplan–Meier analysis. Patients with ADPKD and diabetes had a significantly earlier age at hypertension diagnosis [32.5 (28–40) years] compared to patients with ADPKD alone [38 (35–42) years], P = 0.04.

Fig. 2.

Time to onset of ESRD. From left of figure, dashed line represents ADPKD with diabetes and solid line represents ADPKD no diabetes. Open circles represent censored values in Kaplan–Meier analysis. There was no significant difference in time to onset of ESRD between patients with ADPKD and diabetes [63 (49 to no upper limit) and those with ADPKD alone [65 (61–71) years], P = 0.92.

Fig. 3.

Survival time until death. From left of Figure, dashed line represents ADPKD with diabetes and solid line ADPKD represents no diabetes. Open circles represent censored values in Kaplan–Meier analysis. Patients with ADPKD and diabetes had a trend toward earlier median age at death [65 (52 to no upper limit) years] compared to patients with ADPKD alone [69 (66–80) years], but this difference did not reach significance, P = 0.09.