Neuropsychological functioning, age, and medication adherence in bipolar disorder

PLoS One. 2017 Sep 5;12(9):e0184313. doi: 10.1371/journal.pone.0184313. eCollection 2017.

Abstract

Objectives: Poor adherence to medication is frequent in bipolar disorder (BD) and has been associated with several factors. To date, the relationship between low adherence and neuropsychological functioning in BD is still unclear. As age and neuropsychological functioning might have opposing influences on adherence, our aim was to investigate this link with a particular focus on the effect of age.

Methods: In a cross-sectional study, we included 353 patients divided into two age-groups (16-46; 47-71) from a French cohort diagnosed with BD (type I, II, NOS) and strictly euthymic. All patients had a standardized clinical and neuropsychological assessment and were categorized as high (n = 186) or low (n = 167) adherent based on their score from the Medication Adherence Rating Scale. Clinical information was collected based on a standardized interview and clinical validated scales. Neuropsychological performances were evaluated with an established standardized neuropsychological battery for bipolar disorder patients. After univariate analysis, neuropsychological and clinical predictors of low adherence were included in two age-specific stepwise multiple logistic regressions.

Results: A smaller number of hospitalizations (OR = 0.846, p = 0.012), a shorter illness duration (OR = 0.937, p = 0.003) and higher adverse effects (OR = 1.082, p<0.001) were associated with a greater risk of low adherence in the younger patients. In the older patients, low adherence was also predicted by a smaller number of hospitalizations (OR = 0.727, p = 0.008) and higher adverse effects (OR = 1.124, p = 0.005). Interestingly poor inhibition performance was also a significant predictor of low adherence in older patients (OR = 0.924, p = 0.030).

Conclusions: We found an age-specific relationship between cognitive functioning and adherence in patients with BD. Poor inhibition performances predicted low adherence in older patients only. Our results highlight the need to provide age-adapted therapeutic interventions to improve adherence in patients with BD.

MeSH terms

  • Adult
  • Age Factors
  • Aged
  • Bipolar Disorder / psychology*
  • Demography
  • Female
  • Humans
  • Logistic Models
  • Male
  • Medication Adherence*
  • Middle Aged
  • Neuropsychological Tests

Grant support

This study was financially supported (in part) by the FondaMental foundation (https://www.fondation-fondamental.org/) and by the Investissements d’Avenir program managed by the ANR under reference ANR-11-IDEX-0004-02. The 2 first authors (N.C. and J-L.C.) have received the FACE’s grant from the FondaMental foundation to conduct their research projects on treatment adherence in bipolar patients. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.