Pharmacological primary and secondary cardiovascular prevention among diabetic patients in a multiethnic general practice population: still room for improvements

Abstract

Background Ethnic minority groups have higher prevalence of cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM). We assessed general practitioners’ (GPs’) performance with respect to the pharmacological prevention of CVD in patients with T2DM from different ethnic backgrounds in Oslo.

Methods Of 1653 T2DM patients cared for by 49 GPs in 2005, 380 had a diagnosis of CVD. Ethnicity was categorized as Norwegian, South Asian and other. Risk factor levels, medication use, achievement of treatment targets (HbA1c ≤ 7.5%, systolic blood pressure (SBP) ≤ 140 mmHg, total cholesterol/HDL-cholesterol < 4) and therapeutic intensity (number of drugs targeting each risk factor) were recorded. Chi-square, Wald tests and multiple linear regression analyses were used.

Results Of the 1273 patients receiving primary prevention, 1.5% had their Hb1Ac, 4.8% SBP and 12.7% lipids levels above treatment thresholds without relevant prescriptions. Among patients on pharmacological therapy, 66% reached the HbA1c, 62% SBP and 62% lipid target. Proportions not achieving the HbA1c target were 26% in Norwegians, 38% in South Asians and 29% in others (p = 0.008). Proportions not achieving the SBP target were 42% in Norwegians, 22% in South Asians and 25% in others (p ≤ 0.001). Of those not achieving the HbA1c and SBP targets, 43% and 35% respectively, used only one agent. In secondary prevention, 0.8% of the patients had their HbA1c, 0.5% SBP and 7.4% lipid levels above treatment thresholds without relevant prescriptions. Among patients on pharmacological therapy, 65% reached the HbA1c, 64% SBP and 66% lipid target. Proportions not achieving the HbA1c target were 26% in Norwegians, 47% in South Asians and 40% in others (p = 0.03). Proportions not achieving the SBP target were 36% in Norwegians, 22% in South Asians and 56% in others (p = 0.050). Of those not achieving HbA1c and SBP targets, 49% and 21% respectively, were on mono-therapy.

Conclusions Norwegian GPs comply reasonably well with guidelines for pharmacological prevention of CVD in T2DM patients across ethnic groups. However, lipid-lowering therapy was generally underused, and the achievement of treatment targets for HbA1c in ethnic minorities and for BP in Norwegians could be improved.