Blood pressure status and the incidence of diabetic kidney disease in patients with hypertension and type 2 diabetes.

Objective: Antihypertensive treatment and blood pressure (BP) reduction are known to retard the progression of diabetic kidney disease (DKD) in type 2 diabetes mellitus (T2DM) but long-term real-life clinical data on the incidence of DKD are lacking. In this observational, prospective cohort study, we investigated the association between achievement and maintenance of recommended BP values and the incidence of DKD and its components over a 4-year follow-up in patients with T2DM and hypertension from the Italian Medical Diabetologists registry.

Methods: Clinical records from a total of 12 995 patients with normal renal function and urine albumin excretion at baseline and regular visits during a 4-year follow-up were retrieved and analyzed. The association between recommended, time-updated BP control (BPC) (i.e. ≥75% of visits with SBP and DBP <140/85 mmHg) and the occurrence of renal outcomes was evaluated.

Results: At baseline, 28% of patients (n = 3612) had recommended BP values. Over the 4-year follow-up, 37% (n = 4845) developed DKD, 16% (n = 2061) low glomerular filtration rate and 27% (n = 3487) albuminuria. Patients who failed to achieve and maintain BPC over the study period showed an increased risk of developing DKD [odds ratio (OR) 1.38, P < 0.001], low glomerular filtration rate (OR 1.18, P = 0.03) and albuminuria (OR 1.47, P < 0.001) as compared with those with persistent BPC. These results were consistent after adjustment for covariates and in different subgroups.

Conclusion: Long-term BPC is associated with a reduction in the incidence of DKD and its components in patients with hypertension and T2DM.