An Exploratory Analysis of Sociodemographic, Clinical, and Lifestyle Factors Associated with Insomnia Symptoms and the Relationship Between Insomnia Symptoms and Medication Adherence Among Individuals with Heart Failure.

Background/Objective: Insomnia symptoms are common in persons with heart failure (HF) and
characterized by untoward outcomes. Insomnia symptoms are not clearly understood in persons with HF
as this literature is not yet fully developed. The purpose of this study was to investigate the association
of insomnia symptoms with sociodemographic, clinical, and lifestyle factors and explore the direct and
indirect associations between insomnia symptoms and medication adherence. Methods: This study was
guided by the Neurocognitive model of insomnia and the Riegel and Weaver's conceptual model. A
cross-sectional data analysis on the Health and Retirement Study (HRS) wave 2016 was conducted.
Parametric and non-parametric bivariate and multivariate statistical tests were used in the analysis.
Results: All sociodemographic, clinical, and lifestyle factors had significant bivariate associations with
at least one of the insomnia symptoms (i.e. difficulty initiating sleep (DIS), difficulty maintaining sleep
(DMS), ad early morning awakening (EMA)). In the multivariate analysis adjusted for all covariates,
only age, comorbidity, depressive symptoms, dyspnea, pain, and alcohol consumption maintained their
association with at least one insomnia symptom. Sex and DIS had a borderline significant association
(p=0.053) in the adjusted model. HF significantly predicted DIS (OR=1.23, p <0.05) in the adjusted
model. EMA and DIS but not DMS had significant bivariate and multivariate associations with
cognitive performance. All insomnia symptoms had a bivariate association with medication adherence;
however, none was maintained in the multivariate analysis. Mediation analysis revealed that DIS, DMS,
and EMA had significant indirect effects on medication adherence. Conclusion: Insomnia symptoms
were associated with various sociodemographic, clinical, and lifestyle factors and had indirect effects on
medication adherence. Comorbidities and HF symptoms may mediate the associations between several
sociodemographic factors and insomnia symptoms. The increased sympathetic stimulation in HF could
be contributing to DIS. Insomnia symptoms may be associated with different sleep durations as DMS
was not associated with cognition. Depressive symptoms, fatigue, and cognitive performance mediated
the association between insomnia symptoms and medication adherence.