Systematic Literature Review on Patterns of Pharmacological Treatment and Adherence Among Patients with Bipolar Disorder Type I in the USA

Background: Bipolar disorder type I (BD-I) is a chronic condition characterized by mania episodes followed by syndromic recovery periods, usually permeated by depressive symptoma-tology and recurring acute manic episodes. It requires long-term pharmacological treatment; thus, it is critical to understand the patterns of drug therapy use and medication compliance to better plan health care policies and needs. This systematic literature review aims to study these data among patients with BD-I in the USA, focusing on medications to treat mania.

Methods: Articles published in the last 10 years to October 2016 were searched on MEDLINE and Embase. Studies on patterns of drug therapy, concordance of prescription with clinical practice guidelines, and adherence and persistence with pharmacological treatments for BD-I in the USA under observational conditions, with focus on treatments for mania, were selected.

Results: Treatment prevalence for BD-I is low in the USA, with the most current study showing a 46% 12-month rate. There is a lack of studies addressing the use of long-acting injectable (LAI) antipsychotics. Second-generation antipsychotics (SGAs) have been used by nearly all patients receiving oral antipsychotics since the 2000s. However, 30%-60% of individuals with BD do not receive appropriate treatment, and adherence to oral therapies is poor, with medication possession ratios ≥80% seen in only approximately 60% of patients. For persistence rates, results suggest that treatment duration is short for a condition with recommendation for at least 6 months of maintenance therapy. Literature indicates that LAI SGAs may be related to better adherence and persistence.

Conclusion: There is a need for studies addressing specifically patterns of therapy and adherence to pharmacological treatment in BD-I patients in the USA to better understand the value of current standards, and an urgent need to improve the rates of adherence and persistence to BD-I pharmacotherapy and to increase the understanding of LAI SGAs' potential to address this issue.