Medication patterns and costs associated with olanzapine and other atypical antipsychotics in the treatment of bipolar disorder

Factors related to the comparative effectiveness of clozapine in patients with schizophrenia

AIM

To examine the factors related to the comparative effectiveness of clozapine.

PATIENTS & METHODS

US insurance claims databases were used to identify schizophrenia patients. To examine the factors modifying the comparative effectiveness of clozapine in relation to other second-generation antipsychotics, a series of variables were interacted with a clozapine indicator in regressions.

RESULTS

The impacts of clozapine on both persistence and adherence were significantly modified by prior hospitalization, prior epilepsy diagnosis and prior use of antianginal agents. The relative risks of heavy inpatient services use and heavy emergency department services use were also modified by several factors.

CONCLUSION

Several factors can be used to identify patients who are more likely to benefit from clozapine than other second-generation antipsychotics.

Atypical antipsychotic adherence is associated with lower inpatient utilization and cost in bipolar I disorder

AIMS

This study explored the association between medication adherence to oral atypical antipsychotics (AAP) and both psychiatric hospitalization and associated costs in bipolar I disorder (BD-I) in a real-world setting.

MATERIALS AND METHODS

This retrospective study used the Truven Health MarketScan Medicaid, Commercial, and Medicare Supplemental Claims Databases. Adults were identified if they had BD-I and initiated an AAP treatment during the study identification period (July 1, 2015-June 30, 2016 for Medicaid, July 1, 2015-March 31, 2016 for Commercial and Medicare Supplemental) and had ≥6-month continuous enrollment before (baseline) and after (follow-up) the first day of treatment. Medication adherence was measured by the proportion of days covered (PDC) and grouped as: fully-adherent (PDC ≥80%), partially-adherent (40% ≤ PDC <80%), and non-adherent (PDC <40%). Logistic and linear regression models were conducted to estimate the risk of psychiatric hospitalization and costs during the 6-month follow-up period.

RESULTS

The final sample consisted of 5,892 (32.0%) fully-adherent, 4,246 (23.1%) partially-adherent, and 8,250 (44.9%) non-adherent patients. The adjusted rate of psychiatric hospitalization during the follow-up period was lower in the fully-adherent (6.0%) vs partially- (8.3%) or non-adherent (8.8%) groups (p < 0.001). Using the fully-adherent cohort as the reference group, the odds of psychiatric hospitalization were significantly higher for the partially-adherent (OR = 1.42; 95% CI = 1.23-1.64) and non-adherent (1.51; 1.33-1.71) cohorts. The mean adjusted psychiatric hospitalization cost over 6 months among hospitalized patients was lower for the fully-adherent cohort ($11,748), than the partially-adherent ($15,051 p = 0.002) or non-adherent cohorts ($13,170, not statistically significant).

LIMITATIONS

The medication adherence measures relied on prescription claims data, not actual use.

CONCLUSIONS

In the treatment of BD-I, better medication adherence to AAP was associated with fewer psychiatric hospitalizations. Among hospitalized patients, fully-adherent patients had statistically significantly lower psychiatric costs than partially-adherent ones. These findings suggest that improving adherence to AAP in BD-I may be a valuable goal from both clinical and economic perspectives.

Health Care Utilization and Treatment Persistence Associated with Oral Paliperidone and Lurasidone in Schizophrenia Treatment

BACKGROUND

Oral paliperidone and lurasidone are new second-generation antipsychotics (SGAs). Empirical evidence on the comparative costs and persistence of these 2 agents are absent in the literature.

OBJECTIVE

To assess health care use and persistence associated with the 2 new agents oral paliperidone and lurasidone and other SGAs.

METHODS

Schizophrenia patients who initiated SGA therapy were identified in the January 2007-June 2013 claims databases of a large managed care organization. Multivariate regressions using aripiprazole as the comparator were conducted. Ordinary least squares regressions were used to estimate the total medical and pharmacy costs associated with each drug. Poisson regressions were conducted to evaluate the frequency of hospitalizations and emergency department (ED) visits associated with each drug. A censored regression model was used to evaluate the comparative persistence. Sensitivity analyses using generalized linear models, two-part models, hurdle models, and instrumental variable regressions were also performed.  

RESULTS

Compared with aripiprazole, paliperidone was not associated with significantly different total costs, yet lurasidone was associated with lower total costs (-$7,052; 95% CI = -$9,221, -$4,882). Lurasidone was also associated with significantly lower medical services costs (-$5,025; 95% CI = -$7,096, -$2,955), drug costs (-$2,026; 95% CI = -$2,695, -$1,357), hospital costs (-$3,026; 95% CI = -$4,731, -$1,321), outpatient costs (-$1,999; 95% CI = -$2,536, -$1,463), and ED costs (-$2,284; 95% CI = -$3,069, -$1,499), whereas paliperidone did not have significant effects on any types of costs. Paliperidone users had fewer ED visits (-0.25; 95% CI = -0.42, -0.08), while lurasidone users had fewer hospitalizations (-5.98; 95% CI = -6.61, -5.35) and fewer ED visits (-2.51; 95% CI = -2.92, -2.10). Both paliperidone and lurasidone were associated with lower levels of treatment persistence.

CONCLUSIONS

Paliperidone does not associate with lower total costs compared with commonly used SGAs, whereas lurasidone is associated with lower total health costs. Thus, high access fees of lurasidone are not necessarily a major concern in prescription.

Healthcare resource utilization among patients diagnosed with idiopathic pulmonary fibrosis in the United States

OBJECTIVES

Few studies have characterized healthcare resource utilization among patients with idiopathic pulmonary fibrosis. The objective of this study is to assess healthcare resource utilization among patients with idiopathic pulmonary fibrosis as compared to members without this condition.

METHODS

Patients newly diagnosed with idiopathic pulmonary fibrosis were identified from a national administrative claims database (2006-2011) as having ≥ 2 claims with idiopathic fibrosing alveolitis, or ≥ 1 claim with idiopathic fibrosing alveolitis and ≥ 1 claim with post-inflammatory pulmonary fibrosis (earliest claim with idiopathic fibrosing alveolitis denoted the index date), a procedure of lung biopsy or high-resolution computed tomography within ± 90 days of the index date, 12-month pre-index continuous enrollment, plus ≥ 2 confirmatory idiopathic fibrosing alveolitis diagnoses after the procedure. For each idiopathic pulmonary fibrosis patient, three members without the condition were matched by age/gender/region/payer type. Demographic/clinical characteristics were measured during the 1-year pre-index period. Healthcare resource utilization was assessed by quarter during 1-year pre- and post-index periods. Generalized estimating equation models controlling for patient characteristics were constructed to estimate adjusted post-index healthcare resource utilization.

RESULTS

In total, 1735 patients with idiopathic pulmonary fibrosis and 5205 without (mean age = 71.5 years; 46.1% female) were included. Adjusted results revealed idiopathic pulmonary fibrosis patients were more likely to use healthcare resources than members without the condition 1-year post-index (number of hospitalizations, emergency room visits, and outpatients visits: 0.63 vs 0.31, 0.62 vs 0.48, and 5.7 vs 3.1 per person-year, respectively).

CONCLUSIONS

Healthcare resource utilization is considerably higher among patients with idiopathic pulmonary fibrosis than members without the condition. Effective treatments for patients with idiopathic pulmonary fibrosis are needed to help reduce burden of healthcare resource use.

Efficacy of pharmacotherapy in bipolar disorder: a report by the WPA section on pharmacopsychiatry

The current statement is a systematic review of the available data concerning the efficacy of medication treatment of bipolar disorder (BP). A systematic MEDLINE search was made concerning the treatment of BP (RCTs) with the names of treatment options as keywords. The search was updated on 10 March 2012. The literature suggests that lithium, first and second generation antipsychotics and valproate and carbamazepine are efficacious in the treatment of acute mania. Quetiapine and the olanzapine-fluoxetine combination are also efficacious for treating bipolar depression. Antidepressants should only be used in combination with an antimanic agent, because they can induce switching to mania/hypomania/mixed states/rapid cycling when utilized as monotherapy. Lithium, olanzapine, quetiapine and aripiprazole are efficacious during the maintenance phase. Lamotrigine is efficacious in the prevention of depression, and it remains to be clarified whether it is also efficacious for mania. There is some evidence on the efficacy of psychosocial interventions as an adjunctive treatment to medication. Electroconvulsive therapy is an option for refractory patients. In acute manic patients who are partial responders to lithium/valproate/carbamazepine, adding an antipsychotic is a reasonable choice. The combination with best data in acute bipolar depression is lithium plus lamotrigine. Patients stabilized on combination treatment might do worse if shifted to monotherapy during maintenance, and patients could benefit with add-on treatment with olanzapine, valproate, an antidepressant, or lamotrigine, depending on the index acute phase. A variety of treatment options for BP are available today, but still unmet needs are huge. Combination therapy may improve the treatment outcome but it also carries more side-effect burden. Further research is necessary as well as the development of better guidelines and algorithms for the step-by-step rational treatment.

Applying comparative effectiveness research methods in bipolar disorders

BACKGROUND

Randomized clinical trials [RCT] are the Gold Standard of medical evidence. However, observational comparative effectiveness research [CER] based on real-world data is receiving national attention. This paper demonstrates how observational CER can fill important gaps in clinical knowledge left behind by RCT approaches. An example of CER in bipolar disorders is presented.

METHODS

Paid claims data from a large commercial insurer were used to identify episodes of drug therapy. Episodes were defined each time a patient initiated or restarted therapy using an antipsychotic, antidepressant or mood stabilizing medication. Episode definitions were based on calculations of continuous days of drug therapy using a 15 day gap definition. 105,440 episodes of drug therapy were included in the analysis.

RESULTS

Most episodes were initiated using a mood stabilizing drug (40%) or an antidepressant (40%). Over 59% of all episodes were for augmentation therapy, followed by switching episodes (25%) and restart episodes (16%). Patient outcomes measured by either duration of uninterrupted therapy or one-year post-treatment cost varied significantly with patient treatment history, especially episode type. The comparative effectiveness of alternative therapies was sensitive to the extent to which treatment history is taken into account.

CONCLUSIONS

Observational research can evaluate patient outcomes across a wide range of clinical presentations with regard to the patient's treatment history. Treatment history is a major determinant of patient compliance and future treatment costs. Failure to account for treatment history can introduce bias into comparative effectiveness results. Observational CER research can also uncover important questions that require future research.

Patterns and predictors of antipsychotic medication use among the U.S. population: findings from the Medical Expenditure Panel Survey

BACKGROUND

Given the importance of pharmacological treatment in mental disorders, it is important to have a thorough understanding of predictors and variations in antipsychotic use.

OBJECTIVE

To provide a description of patient characteristics associated with antipsychotic use and to examine predictors of atypical antipsychotic use among antipsychotic users.

METHODS

Data were obtained from the 2004 and 2005 Medical Expenditure Panel Survey. Dependent variables were annual, self-reported, atypical and typical antipsychotic use. Independent variables included predisposing, enabling, and need characteristics according to Andersen's Behavioral Model. In addition to descriptive statistics, logistic regression analyses were performed to examine the determinants of antipsychotic use.

RESULTS

Patients aged 65 and older were 0.63 times as likely to use antipsychotics as patients aged 26-45. Poor and near-poor patients were 1.55 and 1.37 times as likely to use antipsychotics as middle- to high-income patients, respectively. The odds of antipsychotic use were 2.95 and 1.99 times for patients with public and prescription insurance coverage, respectively. Patients with a usual source of health care were 1.51 times as likely to use antipsychotics as those without. Compared with typical antipsychotic use, patients aged 25 and younger were 3.88 times as likely to use atypical antipsychotics as patients aged between 26 and 45. Urban residents were 1.87 times as likely as rural residents to use atypical antipsychotics. The odds of antipsychotic and atypical antipsychotic use for the poor mental health population were 8.73 and 3.87 times as patients with good to excellent mental health status.

CONCLUSIONS

Predisposing and need factors play important roles in determining the use of antipsychotics. However, among antipsychotic users, the use of atypical versus typical antipsychotics appears to have been influenced primarily by need. These findings should be useful to clinicians and policy makers in directing antipsychotic treatments to patients in need.

Longer-term treatment of patients with bipolar disorder: a 9-month observational study in Central and Eastern Europe, the Middle East and Africa

OBJECTIVE

To compare the longer-term outcomes of pharmacological treatment of patients with a diagnosis of bipolar affective disorder currently suffering a manic or hypomanic episode prescribed olanzapine or non-olanzapine medication in naturalistic, clinical practice settings in Bosnia-Herzegovina, Slovakia, Slovenia, Turkey, Saudi Arabia and Egypt.

RESEARCH DESIGN AND METHODS

Prospective, observational, non-interventional study conducted over 9 months. Inpatients or outpatients who initiated or changed oral bipolar mania medication were grouped into (1) those prescribed olanzapine at baseline (n = 569) and (2) those not prescribed olanzapine (n = 325).

MAIN OUTCOME MEASURE(S)

The change from baseline in the Clinical Global Impression Severity scale for bipolar disorder (CGI-BP-S), the rates of symptomatic response and remission (based on CGI-BP-S) and the frequency and nature of treatment-emergent adverse events. Analyses included (1) linear or logistic regression, with adjustment for confounders, based on the last observation carried forward and (2) weighted repeated measures models that adjusted for treatment switching and patient drop-out.

RESULTS

When results were adjusted for treatment switching and patient drop-out, patients prescribed olanzapine had significantly better CGI-BP-S scores (mean difference = -0.24; 95% confidence interval [CI] -0.33, -0.16; p < 0.001) and significantly greater odds of treatment response (odds ratio [OR] = 1.86; 95% CI 1.31, 2.65; p < 0.001) and symptom remission (OR = 1.65; 95% CI 1.18-2.32; p = 0.003) than those not prescribed olanzapine. The frequency of most adverse events decreased in both groups. Patients prescribed olanzapine had significantly greater weight gain from baseline (mean increase = 2.66 kg; 95% CI 2.35, 2.98) compared with those not prescribed olanzapine (mean increase = 1.85 kg; 95% CI 1.51, 2.19; p < 0.001).

CONCLUSIONS

Inclusion of olanzapine is of benefit for pharmacological treatment of patients with bipolar disorder. However, the favourable outcomes observed cannot be directly attributed to olanzapine alone because of the high prevalence of polypharmacy in the patient population.

Dose trends for second-generation antipsychotic treatment of schizophrenia and bipolar disorder

BACKGROUND

Antipsychotic dosing used in clinical practice can differ from dosing originally recommended in product labeling. This has been reported for olanzapine and quetiapine, where higher doses are commonly used. This may be the case for ziprasidone as well.

METHOD

To characterize changes over time in dosing for the initial and subsequent prescriptions of first-line second-generation antipsychotics used during treatment episodes for outpatients with schizophrenia and bipolar disorder, the 2001-2005 Thomson MarketScan Medicaid Database (Medicaid) and the 2001-2006 MarketScan Commercial Claims and Encounters Database (Commercial) were analyzed. Dose trends were evaluated using autoregressive time-series models.

RESULTS

Data were available for 49180 treatment episodes of schizophrenia (4683 Commercial and 44497 Medicaid) and 83289 treatment episodes of bipolar disorder (57961 Commercial and 25328 Medicaid). The initial prescription mean daily and overall mean daily doses of ziprasidone in schizophrenia episodes significantly increased across the Medicaid and Commercial populations, with similar trends observed for bipolar episodes. The first (May 2001) and last (December 2005) observed 3-month mean daily doses for ziprasidone were 112 mg/d and 138 mg/d for patients with schizophrenia and 93 mg/d and 113 mg/d for those with bipolar disorder in the Medicaid cohort, with similar findings for the Commercial cohort. Consistently significant trends in dose changes were not observed for the other medications, although quetiapine and olanzapine doses generally increased while aripiprazole and risperidone doses generally decreased.

CONCLUSIONS

There remains a need for controlled randomized clinical trials that test fixed doses of antipsychotics to ascertain the dose-response relationship within the dose range used in contemporary clinical practice.