Therapeutic adherence in primary care depressed patients: a longitudinal study

Lack of adherence has been associated to lower efficacy of anti-depressant treatment, increasing the risk of recurrence and persistence of clinical symptoms. Patients with poor medication adherence have more concomitant medical illnesses and somatic symptoms. Furthermore, this increases use of healthcare services.

Longitudinal and observational study on therapeutic adherence level in depressive outpatients treated in 3 Primary Care (PC) centers. Eight evaluations during 6 months were carried out in 29 patients over 18, with DSM-IV-TR major depression diagnosis. The purpose of the present study was to determine adherence level, to analyze socio-demographic factors and clinical profiles involved in adherence, and to observe the evolution of depressive symptoms.

Good therapeutic adherence was observed in 72.4% of patients. Significant differences in the Drug Attitude Inventory (U=107.5; p=0.036) were found. This tool evaluates the perceived effect of the medication, with a better perception observed in adherent patients. In those patients a progressive reduction on the Hamilton Depression Scale was found over the course of six monthly follow-up visits, with clinical remission observed in month 4. The analysis of survival rate did not reveal any significant difference between the two groups [Log Rank (χ2=1.610, p=0.205)].

The therapeutic adherence observed in this longitudinal PC study is high, and it is associated with an improvement in the illness. A better perceived effect of the treatment showed a significant connection to an improvement in symptoms of depression.