Predictors of duloxetine adherence and persistence in patients with fibromyalgia

Abstract

ObjectivesAdherence to medication for the treatment of fibromyalgia (FM) is predictive of lower overall health-care costs, and thus a lower burden on both patients and providers. The objectives of this study were to examine the predictors of adherence to and persistence with duloxetine therapy among commercially insured FM patients, and to identify subgroups of patients with high duloxetine persistence and adherence.Study designThis cross-sectional, retrospective study analyzed medical and pharmacy records over 1 year for patients in the US aged 18–64 years with FM who initiated (no prior 90-day use) duloxetine treatment in 2008.MethodsAdherence to duloxetine was measured by medication possession ratio (MPR), with high adherence defined as MPR ≥ 0.8. Persistence was defined as the duration of therapy from the index date to the earliest of: the ending date of the last prescription, the date of the first gap of >15 days between prescriptions, or the end of the study period (12 months). Demographic and clinical predictors of adherence were examined via multiple logistic regression (MLR), and subgroups of duloxetine-persistent and -adherent patients were identified using classification and regression trees (CART).ResultsAmong 4660 duloxetine patients, 33% achieved high adherence. Factors associated with high adherence from MLR included older age, North Central and Northeast regions, prior venlafaxine, pregabalin, selective serotonin reuptake inhibitor (SSRI), or other antidepressant use, or comorbid dyslipidemia or osteoarthritis (all P < 0.05). CART analysis revealed that patients with prior antidepressant use, aged ≥46, or prior osteoarthritis had higher MPR (all P < 0.05), and patients aged ≥45 with a history of SSRI, venlafaxine, or anticonvulsant use had longer duration of therapy (all P < 0.05).ConclusionsPatients with high adherence to and persistence with duloxetine were significantly older and had prior antidepressant use.

Beliefs About GI Medications and Adherence to Pharmacotherapy in Functional GI Disorder Outpatients

“…These rates are higher compared with those previously reported for IBD, excluding patients on anti-TNF therapies who had similarly high rates of adherence (25–27). Although data on medication adherence in FGID patients are sparse, our observed adherence exceeds the 29–45% reported for patients with non-GI functional disorders, such as fibromyalgia (28,29). We hypothesized that adherence would be low in the subgroup of FGID patients on TCAs given their stigmatization as “psychiatric medications” (6,7).…”

Adherence to fibromyalgia treatment: challenges and impact on the quality of life

“…Pharmacological treatment includes pain moderators such as selective serotonin reuptake inhibitor antidepressants (alone) and so-called dual (serotonin and noradrenaline), non-selective tricyclic agents (such as amitriptyline and cyclobenzaprine) and anticonvulsant agents (such as pregabalin and gabapentin) 3,18 . Adherence to FM pharmacological treatment is considered low worldwide, and varies among the different drugs, with tricyclic agents being the most rapidly abandoned, and adherence was higher in the group that received more selective antidepressants [18][19][20]22 . Among the more selective, noradrenaline and serotonin reuptake inhibitors, also known as dual inhibitors, similar to tricyclics, produce central analgesia acting on descending inhibitory nerve pathways.…”

“…Di Matteo et al 4 concluded that the risk of non-adherence is 27% higher in this group, regardless the underlying disease to be treated. Cui et al 20 evaluated the adherence of patients with fibromyalgia to the treatment with duloxetine and showed that one-third of them had a strong adherence, and among them, the predictive factors for better adherence were age above 35 years and previous use of selective antidepressants (serotonergic inhibitors or serotonergic and noradrenergic). The same group of investigators, in a study involving more than 18,000 patients, concluded that adherence and persistent use of duloxetine were similar in groups of patients with depressive disorder, FM and osteoarthritis, and significantly higher than the results found for patients with chronic lower back pain 21 .…”

Duloxetine, a Multitarget Drug

“…High adherence was indicated as MPR ≥ 0.8. Patients with high adherence and persistence with duloxetine were significantly older and had prior antidepressant use [3].…”