Background Many patients delay or interrupt dual antiplatelet therapy (DAT) after drug-eluting stent (DES) implantation, which increases the risk of stent thrombosis and death.

Objective To test the hypothesis that simple telephone contact made by nurses would improve adherence to and persistence of DAT.

Design Randomised controlled trial.

Patients and intervention A total of 300 patients (mean±SD 64±10 years, 73% male) were recruited immediately after DES implantation performed between June 2009 and June 2010. The last patient recruited reached the 1-year follow-up time point in June 2011. Patients were randomised to one of two groups: intervention, with four telephone follow-ups, versus a control group. In the intervention group, phone calls were made within 7 days of the DES implantation and at 1, 6 and 9 months to support drug adherence. Control patients were followed as per usual clinical practice. Pharmacy data were collected to assess drug prescription filling and refill.

Setting Tertiary care university cardiovascular centre and community.

Main outcome measures The primary end point was the proportion of days covered with aspirin and clopidogrel over the year after discharge as assessed by pharmacy refill data. Secondary outcome measures included persistence of aspirin and clopidogrel treatment, defined as no gaps longer than 14 days during follow-up.

Results Most patients (73%) underwent DES implantation in the context of an acute coronary syndrome. All patients had drug insurance cover, either from the public plan (59%) or through private plans (41%). Complete pharmacy follow-up data were available for 96% of the cohort. At 12 months, median scores (25th–75th centile) for adherence to aspirin and clopidogrel were 99.2% (97.5–100%) and 99.3% (97.5–100%), respectively, in the intervention group compared with 90.2% (84.2–95.4%) and 91.5% (85.1–96.0%), respectively, in the control group (p<0.0001 for aspirin and clopidogrel). Patients in the intervention group were significantly more persistent in the aspirin and clopidogrel treatment than those in the control group. For clopidogrel, 87.2% of patients in the intervention group were still persistent at 12 months compared with only 43.1% in the control group (p<0.0001).

Conclusions A simple approach of four telephone calls to patients after DES implantation significantly improved 1-year drug adherence to near-perfect scores. Persistence of DAT was also significantly improved by the intervention.