Nonalbuminuric diabetic kidney disease linked to poor outcomes

Patients with nonalbuminuric diabetic kidney disease (DKD) are at increased risk of adverse outcomes, such as hospitalization for heart failure (HHF) and progression to chronic kidney disease (CKD), regardless of kidney function at baseline, a study has found.

The study included 19,025 Chinese adults (mean age 61.1 years, 58.3 percent male) with type 2 diabetes enrolled in the Hong Kong Diabetes Biobank. Researchers defined DKD phenotypes by baseline estimated glomerular filtration rate (eGFR) and albuminuria: no DKD (without decreased eGFR or albuminuria), albuminuria without decreased eGFR, decreased eGFR without albuminuria (nonalbuminuric DKD), and albuminuria with decreased eGFR (albuminuric DKD).

The mean diabetes duration of the population was 11.1 years. Of the patients, 51 percent had no DKD, 29 percent had albuminuria only, 5 percent had decreased eGFR only, and 15 percent had albuminuria plus decreased eGFR.

Compared with patients who had albuminuric DKD (albuminuria only or plus decreased eGFR), those with nonalbuminuric DKD had lower systolic blood pressure, body mass index, HbA_1C, and fewer prevalent diabetic retinopathy.

Over 54,260 person-years of follow-up, a total of 438 deaths, 1,076 cardiovascular disease (CVD) events, 298 HHF, and 1,161 episodes of CKD progression occurred. Compared with the no DKD group, the nonalbuminuric DKD group had higher risks of all-cause mortality (hazard ratio [HR] 1.59, 95 percent confidence interval [CI], 1.04–2.44), HHF (HR, 3.08, 95 percent CI, 1.82–5.21), and CKD progression (HR, 2.37, 95 percent CI, 1.63–3.43). There was no significant increase seen in the risk of CVD (HR, 1.14, 95 percent CI, 0.88–1.48).

A sensitivity analysis that excluded patients with baseline eGFR <30 mL/min/1.73 m² yielded similar results.