Predictors of nonadherence among individuals with bipolar disorder receiving treatment in a community mental health clinic.

BACKGROUND: Subjective experience of illness is a critical component of treatment adherence in populations with bipolar disorder (BPD). This cross-sectional analysis examined clinical and subjective variables in relation to adherence in 140 individuals with BPD receiving treatment with mood-stabilizing medication.

METHODS: Nonadherence was defined as missing 30% or more of medication on the Tablets Routine Questionnaire, a self-reported measure of medication treatment adherence. Adherent and nonadherent groups were compared on measures of attitudes toward illness and treatment including the Attitudes toward Mood Stabilizers Questionnaire, the Insight and Treatment Attitudes Questionnaire, the Rating of Medication Influences, and the Multidimensional Health Locus of Control Scale.

RESULTS: Except for substance abuse comorbidity, adherent individuals (n = 113, 80.7%) did not differ from nonadherent individuals (n = 27, 19.3%) on clinical variables. However, nonadherent individuals had reduced insight into illness, more negative attitudes toward medications, fewer reasons for adherence, and more perceived reasons for nonadherence compared with adherent individuals. The strongest attitudinal predictors for nonadherence were difficulties with medication routines (odds ratio = 2.2) and negative attitudes toward drugs in general (odds ratio = 2.3).

LIMITATIONS: Results interpretation is limited by cross-sectional design, self-report methodology, and sample size.

CONCLUSIONS: Comorbid substance abuse, negative attitudes toward mood-stabilizing medication, and difficulty managing to take medication in the context of one's daily schedule are primary determinants of medication treatment adherence. A patient-centered collaborative model of care that addresses negative attitudes toward medication and difficulty coping with medication routines may be ideally suited to address individual adherence challenges.