Association Between Adherence Barriers, Self-Reported Adherence, and Psychiatric Symptoms Among Adults With Bipolar...

While suboptimal medication adherence is a widely recognized problem for people with bipolar disorder (BD), it is less clear how individual characteristics are associated with varying levels of adherence and how specific adherence barriers impact behaviors. This interim analysis from an ongoing randomized controlled trial (RCT) examined associations between patient-reported adherence, adherence barriers, and mood symptoms among poorly adherent individuals with BD.

RCT participants were adults age ≥ 18 years old with BD Type 1 or 2, difficulties with medication adherence, and actively symptomatic as measured by Brief Psychiatric Rating Scale (BPRS) score ≥ 36, Young Mania Rating Scale (YMRS) > 8, or Montgomery Asberg Depression Rating Scale (MADRS) > 8. Adherence was assessed using the self-reported Tablets Routine Questionnaire (TRQ) and grouped into 3 clinically relevant groups: those with TRQs < 20% (good adherence), ≥ 20% and < 50% (fair adherence), and ≥ 50% (poor adherence). Adherence barriers were assessed with the Oxford Bipolar Knowledge Questionnaire (OBQ), Self-Report Habit Index (SRHI), Communication Styles Scale (CSS), and Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES 8A).

Analysis was derived from screening and baseline data on the first 129 randomized participants. Mean age was 42.18 (SD = 13.04) years, with 76.74% (n = 99) female and 41.09% (n = 53) non-White. The mean past 7-day percentage of days with missed BD medications using TRQ was 34.34% (SD = 30.32) at screening and 24.82% (SD = 27.70) at baseline. The average time between screening visit and baseline was 18.90 (SD = 12.46) days. Comparing adherence groups, MADRS and BPRS were significantly higher in those with worse adherence both at screening and baseline (p < 0.05 for all). With respect to BD adherence barriers, only SRHI was significantly inversely correlated with TRQ at screening (p < 0.001) and both SRHI and SOCRATES 8A (Taking steps sub-scale) were significantly inversely correlated with TRQ at baseline (p = 0.001 and p = 0.022, respectively).

Poorly adherent individuals with BD have significantly more severe global psychopathology and worse depressive severity. Significant adherence barriers include lifestyle routines that do not promote regular medication-taking and engagement in reducing the use of substances. Given the extensive burden of poor adherence in BD, adherence promotion efforts should target specific and actionable barriers.

ClinicalTrials.gov identifier: NCT04622150.