A randomized, controlled study showed that a telephone-based nursing strategy was effective to improve adherence to antipsychotic treatment in clinically stable outpatients with schizophrenia. Post hoc analysis was carried out to identify factors associated with intervention success.

Patients (n= 865) were randomized to receive monthly telephone calls from a nurse or standard clinical follow-up. Calls were performed at weeks 4, 8, and 12, consisting of a brief semistructured interview to assess adherence and attitudes toward medication (DAI-10). Primary endpoint: difference in the percentage of adherent patients after phone follow-up versus control group at week 16. Non conditional logistic regression with backward stepwise procedure was used to identify variables involved with adherence improvement.

410 (96.7%) patients fulfilled adherence criteria in the intervention group vs 402 (91.1%) in the control group. A difference of 5.5% was found between groups (95% CI 2.3, 8.6%; p= 0.0007).

The telephone intervention was significantly associated with an improvement in adherence in those patients with a prior negative attitude toward treatment (OR 4.7, 95% CI 2.4, 9.0; p< 0.0001), but there was not a significant association in patients with a previous positive perception (OR 1.2, 95% CI 0.8, 1.9; p= 0.36). A slight concordance was obtained between adherence improvement after the intervention and the improvement in attitude toward treatment (kappa 0.21, 95% CI 0.15, 0.27).

A nurse telephone follow-up could be a complementary and easy to implement strategy to improve therapeutic adherence, particularly in those patients with negative attitudes toward antipsychotic treatment.