Prioritization of patient-related factors according to renal function in antidiabetic drug selection: the REDIM Project

Aims: Few studies have evaluated how physicians prioritize renal function among other patient-related factors when stepping-up in antidiabetic treatment.

Methods: The REDIM Spanish national online survey included 550 internists. We firstly tested proficiency in chronic kidney disease (Agrawal's Questionnaire) and motivation in diabetes (DAS-3p Questionnaire). We then analyzed how physicians prioritized renal function, age, weight, glycemic control, non-renal co-morbidities and patient perceptions in five varying fictitious clinical scenarios (generic; ambulatory vs. high cardiovascular risk hospitalized patient, for estimated glomerular filtration rates (eGFRs)=50 vs. 25 ml/min/1.73 m(2)). We assigned every item a score (from 5 to 0, highest to lowest relevance) per-physician and compared mean values between clinical scenarios using the t-test for independent means (nominal significance at p<0.05).

Results: Completion rate was 57.5% (N=316; mean age, 46.3 years; men, 71%). Average scores were 22.6 ± 3.9 (possible range [0-30]) for Agrawal's Questionnaire and 4.1 ± 0.6 (range [1-5]) for DAS-3p Questionnaire. In the generic scenario, renal function had the highest priority (mean=3.36 ± 1.66, range [0-5]). When eGFR was set at 50 ml/min/1.73 m(2), physicians prioritized glycemic control for ambulatory (mean=3.23 ± 1.59) and non-renal co-morbidities for hospitalized patients (mean=3.20 ± 1.68) over renal function (mean=3.18 ± 1.77 for ambulatory, p=0.032; mean=3.11 ± 1.65 for hospitalized patients, p=0.002). When eGFR was subsequently lowered to 25 ml/min/1.73 m(2), renal function again led priorities (mean values=3.73 ± 2.05 for ambulatory and 3.75 ± 1.96 for hospitalized patients; both p<0.001).

Conclusions: Knowledge of the degree of renal function impairment induced physicians to prioritize patient-related factors differently when adding a second antidiabetic drug. Renal function led priorities when severely impaired.