Time to lack of persistence with pharmacological treatment among patients with current depressive episodes: a natural study with 1-year follow-up

Abstract

IntroductionMedication nonadherence remains a big challenge for depressive patients. This study aims to assess and compare the medication persistence between unipolar depression (UD) and bipolar depression (BD).MethodsA total of 146 UD and 187 BD patients were recruited at their first index prescription. Time to lack of persistence with pharmacological treatment (defined as a gap of at least 60 days without taking any medication) was calculated, and clinical characteristics were collected. Final diagnosis was made at the end of 1-year follow-up.ResultsA total of 101 (69.2%) UD and 126 (67.4%) BD patients discontinued the treatment, with a median duration of 36 days and 27 days, respectively. No significant difference was found between UD and BD in terms of time to lack of persistence with pharmacological treatment. The highest discontinuation rate (>40%) occurred in the first 3 months for both groups of patients. For UD patients, those with a higher risk of suicide (odds ratio [OR] =0.696, P=0.035) or comorbidity of any anxiety disorder (OR =0.159, P<0.001) were less likely to prematurely drop out (drop out within the first 3 months), while those with onset in the summer (OR =4.702, P=0.049) or autumn (OR =7.690, P=0.012) were more likely to prematurely drop out than those with onset in the spring (OR =0.159, P<0.001). For BD patients, being female (OR =2.250, P=0.012) and having a history of spontaneous remission or switch to hypomania (OR =2.470, P=0.004) were risk factors for premature drop out, while hospitalization (OR =0.304, P=0.023) and misdiagnosis as UD (OR =0.283, P<0.001) at the first index prescription were protective factors.LimitationConservative definition of nonadherence, low representativeness of sample.ConclusionTreatment discontinuation was frequently seen in patients with UD or BD, especially in the first 3 months of treatment. In spite of the similar pattern of medication persistence, UD and BD differ from each other in predictors of premature drop out.

Patterns of persistence with pharmacological treatment among patients with current depressive episode and their impact on long-term outcome: a naturalistic study with 5-year follow-up

“…We are not aware of prior studies that have ever explored and compared such predictive model between UD and BD patients. Although our previous study found that predictors of premature dropout differed between UD and BD, 4 in the absence of replicating data, it is still premature to extensively speculate that such difference reflects different nature of these two diseases.…”

“… 3 However, previous studies have shown that the rates of adherence to medication among patients with MDE are less than optimal. For instance, in our previous study, 4 more than 60% patients with MDE abandoned medication treatment within 12 months after treatment initiation, and over 40% gave up treatment in the first 3 months. Similar treatment discontinuation rates are also seen in other studies.…”

“…Participants from our previous study were included in this study. 4 They were experiencing a current MDE which met the Diagnostic and Statistical Manual of Mental Disorders – Text Revision (DSM-IV-TR) criteria, were seeking medication treatment for the first time, aged between 16 and 65 years. All patients and their legal guardians provided written informed consent.…”

“…The clinical characteristics of all participants have been described elsewhere. 4 All procedures used in the present study were reviewed and approved by the Clinical Research Ethics Committee of the Third Affiliated Hospital of Sun Yat-Sen University.…”

“…Justification for this definition is given in detail in our previous study. 4 Correspondingly, an episode of medication treatment is defined as a consecutive course of treatment without medication treatment interruption. Adherence to medication is measured in two ways: first, time to lack of persistence (TLP) is calculated from the date of the first prescription to the date when pharmacological treatment is actually discontinued.…”