Adherence to medication is associated with non-planning impulsivity in euthymic bipolar disorder patients

Abstract

Background: Adherence to medication is a major issue in bipolar disorder. Non-planning impulsivity, defined as a lack of future orientation, has been demonstrated to be the main impulsivity domain altered during euthymia in bipolar disorder patients. It was associated with comorbidities.

Methods: To investigate relationship between adherence to medication and non-planning impulsivity, we included 260 euthymic bipolar patients. Adherence to medication was evaluated by Medication Adherence Rating Scale and non-planning impulsivity by Barrat Impulsiveness Scale. Univariate analyses and linear regression were used. We conducted also a path analysis to examine whether non-planning impulsivity had direct or indirect effect on adherence, mediated by comorbidities.

Results: Adherence to medication was correlated with non-planning impulsivity, even after controlling for potential confounding factors in linear regression analysis (Beta standardized coefficient = 0.156; p = 0.015). Path analysis demonstrated only a direct effect of non-planning impulsivity on adherence to medication, and none indirect effect via substance use disorders and anxiety disorders.

Limitations: Our study is limited by its cross-sectional design and adherence to medication was assessed only by self-questionnaire.

Conclusions: Higher non-planning impulsivity is associated with low medication adherence, without an indirect effect via comorbidities.

Keywords: Anxiety disorders; Impulsivity; Mood disorders; Substance Use Disorders.