| 1 | Curr Med Res Opin 2009 Sep 25: 2303-10 |
|---|---|
| PMID | 19635045 |
| Title | Good and poor adherence: optimal cut-point for adherence measures using administrative claims data. |
| Abstract | To identify the adherence value cut-off point that optimally stratifies good versus poor compliers using administratively derived adherence measures, the medication possession ratio (MPR) and the proportion of days covered (PDC) using hospitalization episode as the primary outcome among Medicaid eligible persons diagnosed with schizophrenia, diabetes, hypertension, congestive heart failure (CHF), or hyperlipidemia. This was a retrospective analysis of Arkansas Medicaid administrative claims data. Patients > or =18 years old had to have at least one ICD-9-CM code for the study diseases during the recruitment period July 2000 through April 2004 and be continuously eligible for 6 months prior and 24 months after their first prescription for the target condition. Adherence rates to disease-specific drug therapy were assessed during 1 year using MPR and PDC. MAIN OUTCOME MEASURE AND ANALYSIS SCHEME: The primary outcome measure was any-cause and disease-related hospitalization. Univariate logistic regression models were used to predict hospitalizations. The optimum adherence value was based on the adherence value that corresponded to the upper most left point of the ROC curve corresponding to the maximum specificity and sensitivity. The optimal cut-off adherence value for the MPR and PDC in predicting any-cause hospitalization varied between 0.63 and 0.89 across the five cohorts. In predicting disease-specific hospitalization across the five cohorts, the optimal cut-off adherence values ranged from 0.58 to 0.85. This study provided an initial empirical basis for selecting 0.80 as a reasonable cut-off point that stratifies adherent and non-adherent patients based on predicting subsequent hospitalization across several highly prevalent chronic diseases. This cut-off point has been widely used in previous research and our findings suggest that it may be valid in these conditions; it is based on a single outcome measure, and additional research using these methods to identify adherence thresholds using other outcome metrics such as laboratory or physiologic measures, which may be more strongly related to adherence, is warranted. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 2 | Value Health 2009 Sep 12: 989-95 |
| PMID | 19402852 |
| Title | Prospective validation of eight different adherence measures for use with administrative claims data among patients with schizophrenia. |
| Abstract | The aim of this study was to compare the predictive validity of eight different adherence measures by studying the variability explained between each measure and hospitalization episodes among Medicaid-eligible persons diagnosed with schizophrenia on antipsychotic monotherapy. This study was a retrospective analysis of the Arkansas Medicaid administrative claims data. Continuously eligible adult schizophrenia (ICD-9-CM = 295.**) patients on antipsychotic monotherapy were identified in the recruitment period from July 2000 through April 2004. Adherence rates to antipsychotic therapy in year 1 were calculated using eight different measures identified from the literature. Univariate and multivariable logistic regression models were used to prospectively predict all-cause and mental health-related hospitalizations in the follow-up year. Adherence rates were computed for 3395 schizophrenic patients with a mean age of 42.9 years, of which 52.5% (n = 1782) were females, and 52.8% (n = 1793) were white. The proportion of days covered (PDC) and continuous measure of medication gaps measures of adherence had equal C-statistics of 0.571 in predicting both all-cause and mental health-related hospitalizations. The medication possession ratio (MPR) continuous multiple interval measure of oversupply were the second best measures with equal C-statistics of 0.568 and 0.567 for any-cause and mental health-related hospitalizations. The multivariate adjusted models had higher C-statistics but provided the same rank order results. MPR and PDC were among the best predictors of any-cause and mental health-related hospitalization, and are recommended as the preferred adherence measures when a single measure is sought for use with administrative claims data for patients not on polypharmacy. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 3 | Value Health 2009 Sep 12: 989-95 |
| PMID | 19402852 |
| Title | Prospective validation of eight different adherence measures for use with administrative claims data among patients with schizophrenia. |
| Abstract | The aim of this study was to compare the predictive validity of eight different adherence measures by studying the variability explained between each measure and hospitalization episodes among Medicaid-eligible persons diagnosed with schizophrenia on antipsychotic monotherapy. This study was a retrospective analysis of the Arkansas Medicaid administrative claims data. Continuously eligible adult schizophrenia (ICD-9-CM = 295.**) patients on antipsychotic monotherapy were identified in the recruitment period from July 2000 through April 2004. Adherence rates to antipsychotic therapy in year 1 were calculated using eight different measures identified from the literature. Univariate and multivariable logistic regression models were used to prospectively predict all-cause and mental health-related hospitalizations in the follow-up year. Adherence rates were computed for 3395 schizophrenic patients with a mean age of 42.9 years, of which 52.5% (n = 1782) were females, and 52.8% (n = 1793) were white. The proportion of days covered (PDC) and continuous measure of medication gaps measures of adherence had equal C-statistics of 0.571 in predicting both all-cause and mental health-related hospitalizations. The medication possession ratio (MPR) continuous multiple interval measure of oversupply were the second best measures with equal C-statistics of 0.568 and 0.567 for any-cause and mental health-related hospitalizations. The multivariate adjusted models had higher C-statistics but provided the same rank order results. MPR and PDC were among the best predictors of any-cause and mental health-related hospitalization, and are recommended as the preferred adherence measures when a single measure is sought for use with administrative claims data for patients not on polypharmacy. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 4 | Ann Pharmacother 2009 Jan 43: 36-44 |
| PMID | 19126828 |
| Title | Contrasting measures of adherence with simple drug use, medication switching, and therapeutic duplication. |
| Abstract | Multiple measures of adherence have been reported in the research literature and it is difficult to determine which is best, as each is nuanced. Occurrences of medication switching and polypharmacy or therapeutic duplication can substantially complicate adherence calculations when adherence to a therapeutic class is sought. To contrast the Proportion of Days Covered (PDC) adherence metric with 2 variants of the Medication Possession Ratio (MPR, truncated MPR). This study was a retrospective analysis of the North Carolina Medicaid administrative claims data from July 1999 to June 2000. Data for patients with schizophrenia (ICD-9-CM code 295.xx) who were not part of a health maintenance organization, not hospitalized, and not pregnant, taking at least one antipsychotic, were aggregated for each person into person-quarters. The numerator for PDC was defined as the number of days one or more antipsychotics was available and the MPR numerator was defined as the total days' supply of antipsychotics; both were divided by the total days in each person-quarter. Adherence rates were estimated for subjects who used only one antipsychotic, switched medications, or had therapeutic duplication in the quarter. The final sample consisted of 25,200 person-quarters from 7069 individuals. For person-quarters with single antipsychotic use, adherence to antipsychotics as a class was: PDC 0.607, truncated MPR 0.640, and MPR 0.695 (p < 0.001). For person-quarters with switching, the average MPR was 0.690, truncated MPR was 0.624, and PDC was 0.562 (p < 0.001). In the presence of therapeutic duplication, the PDC was 0.669, truncated MPR was 0.774, and MPR was 1.238 (p < 0.001). The PDC provides a more conservative estimate of adherence than the MPR across all types of users; however, the differences between the 2 methods are more substantial for persons switching therapy and prescribed therapeutic duplication, where MPR may overstate true adherence. The PDC should be considered when a measure of adherence to a class of medications is sought, particularly in clinical situations in which multiple medications within a class are often used concurrently. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 5 | Community Ment Health J 2010 Jun 46: 265-72 |
| PMID | 20091226 |
| Title | Antidepressant and antipsychotic use and adherence among Medicaid youths: differences by race. |
| Abstract | The purpose of our study is to use Medicaid data to examine the relationship between race and (a) whether youth with schizophrenia or depression diagnoses receive anti-psychotic and antidepressant prescriptions and (b) adherence to anti-psychotics and antidepressants. The analysis is based on claims files from January 1, 2000 through June 30, 2001. To assess adherence, we used the Proportion of Days Covered (PDC) measure. Multivariable logistic regression was used to analyze the data. Black children with schizophrenia were significantly less likely to be adherent to anti-psychotics during a quarter than White children. White children with depression were significantly more likely to receive an antidepressant prescription and they were significantly more adherent during a quarter than Black children. Providers should make sure to investigate both youth and caregiver concerns, fears, and barriers to using these medications and work with the families to develop strategies to improve medication use among youth. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 6 | Pharmacopsychiatry 2012 Jun 45: 138-45 |
| PMID | 22174026 |
| Title | Psychotropic drug treatment, clinical characteristics and cognitive processing speed in patients with schizophrenia: results from the ELAN study. |
| Abstract | Psychotropic drug combinations (PDC) are common in the treatment of patients with schizophrenia but there is little research regarding the effects of PDC on cognition. The aim of this study was to analyse the effects of antipsychotic monotherapy and various types of PDC on cognitive processing speed (CPS). ELAN is a 24-month multi-site prospective observational controlled trial following up 374 patients with schizophrenia under routine treatment conditions following discharge from inpatient treatment. The propensity score method, multinomial logistic regression analyses and mixed effects regression models were used. CPS correlated significantly with PANSS and GAF scores and improved over time in the monotherapy group. Negative effects of some PDC (antipsychotics + tranquilizers/antipsychotics+at least 2 other psychopharmacological subclasses, sedative/anticholinergic drugs/high adjusted antipsychotic dose) lost significance after controlling for clinical characteristics. Indications for PDC should be examined with care although, in the present study, effects on cognition were small. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 7 | BMC Psychiatry 2013 -1 13: 246 |
| PMID | 24094241 |
| Title | Antipsychotic adherence patterns and health care utilization and costs among patients discharged after a schizophrenia-related hospitalization. |
| Abstract | This study aimed to assess antipsychotic adherence patterns and all-cause and schizophrenia-related health care utilization and costs sequentially during critical clinical periods (i.e., before and after schizophrenia-related hospitalization) among Medicaid-enrolled patients experiencing a schizophrenia-related hospitalization. All patients aged ? 18 years with a schizophrenia-related inpatient admission were identified from the MarketScan Medicaid database (2004-2008). Adherence (proportion of days covered [PDC]) to antipsychotics and schizophrenia-related and all-cause health care utilization and costs were assessed during preadmission (182- to 121-day, 120- to 61-day, and 60- to 0-day periods; overall, 6 months) and postdischarge periods (0- to 60-day, 61- to 120-day, 121- to 180-day, 181- to 240-day, 241- to 300-day, and 301- to 365-day periods; overall, 12 months). Health care utilization and costs (2010 US dollars) were compared between each adjacent 60-day follow-up period after discharge using univariate and multivariable regression analyses. No adjustment was made for multiplicity. Of the 2,541 patients with schizophrenia (mean age: 41.2 years; 57% male; 59% black) who were identified, approximately 89% were "discharged to home self-care." Compared with the 60- to 0-day period before the index inpatient admission, greater mean adherence as measured by PDC was observed during the 0- to 60-day period immediately following discharge (0.46 vs. 0.78, respectively). The mean PDC during the overall 6-month preadmission period was lower than during the 6-month postdischarge period (0.53 vs. 0.69; P < 0.001). Compared with the 0- to 60-day postdischarge period, schizophrenia-related health care costs were significantly lower during the 61- to 120-day postdischarge period (mean: $2,708 vs. $2,102; P < 0.001); the primary cost drivers were rehospitalization (mean: $978 vs. $660; P < 0.001) and pharmacy (mean: $959 vs. $743; P < 0.001). Following the initial 60-day period, both all-cause and schizophrenia-related costs declined and remained stable for the remaining postdischarge periods (days 121-365). Although long-term (e.g., 365-day) adherence measures are important, estimating adherence over shorter intervals may clarify the course of vulnerability to risk and enable clinicians to better design adherence/risk-related interventions. The greatest risk of rehospitalization and thus greater resource utilization were observed during the initial 60-day postdischarge period. Physicians should consider tailoring management and treatment strategies to help mitigate the economic and humanistic burden for patients with schizophrenia during this period. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 8 | J Psychiatr Res 2013 Apr 47: 460-6 |
| PMID | 23317876 |
| Title | The incidence and all-cause mortality of pneumonia in patients with schizophrenia: a nine-year follow-up study. |
| Abstract | This study sought to estimate the incidence, all-cause mortality and relative risks for patients with schizophrenia after a pneumonia diagnosis. The population was identified from the Taiwanese National Health Insurance Research Database (NHIRD) in 1999 and included 59,021 patients with schizophrenia and 236,084 age- and sex-matched control participants without schizophrenia. These participants were randomly selected from the 23,981,020-participant NHIRD, which contain 96% of the entire population. Using the 2000-2008 NIHRD, the incidence and nine-year pneumonia-free survival rate of pneumonia (ICD-9-CM codes 486 and 507.0-507.8) were calculated. Over nine years, 6055 (10.26%) patients with schizophrenia and 7844 (3.32%) controls had pneumonia. The pneumonia incidence density was 11.4/1000 person-years among the patients with schizophrenia, who experienced a 3.09-fold increased risk of developing pneumonia. After adjusting for other covariates, the patients with schizophrenia still experienced a 1.77-fold increased risk of developing pneumonia. Although, without adjustment, fewer schizophrenia patients than controls died after having pneumonia (2121 [35.12%] vs. 3497 [44.62%]), after adjusting for other variables, the mortality hazard ratio for patients with schizophrenia was 1.39. During a nine-year follow-up, the likelihood of developing pneumonia and all-cause mortality among patients with schizophrenia was higher than that of the non-schizophrenia group as was the mortality rate. Interestingly, the psychiatric proportion of days covered (PDC) was positively associated with pneumonia (OR: 2.51) but negatively associated with death (HR: 0.72). These findings imply the importance of iatrogenic factors and psychotropic drugs (including their benefits and side effects) and highlight the directions for future studies. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 9 | Schizophr. Res. 2014 Nov 159: 322-8 |
| PMID | 25445622 |
| Title | The risks of major osteoporotic fractures in patients with schizophrenia: a population-based 10-year follow-up study. |
| Abstract | The aim of the study is to explore the incidence and the risks associated with major osteoporotic fractures, all-cause mortality with osteoporotic fractures and the effect of the psychiatric drug exposure in patients with schizophrenia during a 10-year follow-up period. Two nationwide cohorts were selected from the Taiwan National Health Insurance Research Database (NHIRD) consisting of 30,335 patients with schizophrenia (age ? 40 years) and 121,340 age- and sex-matched control participants without schizophrenia. The psychiatric proportion of days covered (PDC) is an indicator of the intensity of drug exposure in patients with schizophrenia. The incidence and risk factors of major osteoporotic fractures were calculated for both cohorts. Additionally, the patient survival rate after major osteoporotic fractures was also calculated. During a 10-year follow-up period, 1677 (5.53%) schizophrenia and 4257 (3.51%) control subjects had major osteoporotic fractures (P < 0.001). The schizophrenia patients with a PDC > 0.1 showed a significantly higher incidence of major osteoporotic fractures than did the non-schizophrenia controls; however, those with a psychiatric PDC ? 0.1 did not. After adjustment, the psychiatric PDC was significantly and independently associated with the risk of major osteoporotic fractures except some medical morbidities but the schizophrenia diagnosis was not. In addition, among all 5934 patients with major osteoporotic fracture, the adjusted mortality hazard ratio for psychiatric PDC was 1.92 (95% CI = 1.63-2.26). Patients with schizophrenia are at a higher risk for major osteoporotic fractures than the general population and also have a higher mortality rate due to major osteoporotic fractures. These findings may be caused by psychiatric drug use rather than schizophrenia, which suggests that directions can be taken in future studies. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 10 | J Manag Care Spec Pharm 2014 Jul 20: 756-66 |
| PMID | 24967528 |
| Title | Methodological considerations in estimating adherence and persistence for a long-acting injectable medication. |
| Abstract | Measures of medication adherence and persistence are important for researchers and policymakers to assess quality of care. Lack of adherence has been associated with adverse outcomes and higher costs of care. Long-acting medication formulations, including injectable forms, have been proposed as interventions to increase adherence and in turn improve health outcomes and costs. Standard measures of adherence/persistence were developed for orally administered medications. Methods for assessing adherence/persistence of long-acting injectable dose forms are understudied. To compare the consistency between standard measures of adherence/persistence versus proposed variations that consider the data quality and injectable administration method for a long-acting injectable second-generation antipsychotic (SGA) using an orally administered SGA as the reference. Standard adherence/persistence measures were designed for oral tablet formulations, in particular accounting for accumulation of pills caused by early refills. To address this limitation and the accuracy of the days supply field for long-acting injectable SGAs in pharmacy claims, 2 alternatives are proposed. The first approach calculates days supply using the labeled dosing schedule for the given injectable. The second approach builds on the first and sets days supply to the minimum of the time between injections and the time frame according to the labeled dosing schedule. Administrative health care claims data from the Missouri Medicaid system were analyzed to compare adherence/persistence measures between formulations. Common adherence/persistence measures, including medication possession ratio (MPR) and proportion of days covered (PDC), were evaluated in this study. The analysis cohorts comprised 195 adult patients with schizophrenia who initiated a long-acting injectable SGA (LA-SGA) and 369 patients initiating an oral SGA (O-SGA) from August 1, 2009, through April 30, 2010. Chi-squared tests, the Kruskal-Wallis test, and Kaplan-Meier curves were used to compare adherence/persistence measures between cohorts. Days supply was most frequently recorded as 30 days for O-SGA and 28 days for LA-SGA. Time between claim fills was most commonly 28 days for both cohorts. Using the LA-SGA pharmacy claims data, MPR was 0.91 and did not vary significantly from MPR of O-SGA (0.90; test statistic?=?0.29, P?=?0.590). When applying the labeled dosing schedule to compute days supply, the LA-SGA MPR rose to 0.97 and varied significantly from MPR of O-SGA (test statistic?=?9.60, P?=?0.002). Additionally controlling for the inability for excess medication accumulation, MPR for LA-SGA dropped to 0.86, which varied significantly from MPR of O-SGA (test statistic?=?4.01, P?=?0.045). PDC varied from 0.55 to 0.61 for LA-SGA but was consistently significantly different from the 0.37 PDC value of O-SGA (P? less than ?0.05 for each comparison). Standard medication adherence/persistence measures yielded different conclusions when comparing a LA-SGA and an O-SGA, depending on the measure and underlying assumption for days supply. Adherence/persistence measures that address pharmacological differences in terms of formulation and duration of therapeutic drug levels between medications may be necessary and are particularly important as more injectable antipsychotic medications are approved in the United States. Therefore, payers and investigators should consider sensitivity analysis using different adherence/persistence definitions when making product comparisons to ensure confidence in conclusions. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 11 | Curr Med Res Opin 2015 -1 31: 1437-48 |
| PMID | 25978698 |
| Title | Evaluation of a comprehensive information and assistance program for patients with schizophrenia treated with long-acting injectable antipsychotics. |
| Abstract | While atypical long-acting injectable antipsychotics (LAIs) offer the potential for increased adherence, access to medication poses challenges that may hinder their use. Janssen Connect * *Janssen Connect is a registered trade name of Janssen Scientific Affairs, LLC, Titusville, NJ, USA. (JC), a comprehensive information and assistance program, was designed to help patients who received a Janssen LAI initiate and maintain treatment after their health care professional (HCP) determined that the medication was the most clinically appropriate option. We conducted a formative and impact evaluation on early medication adherence of patients enrolled in JC and prescribed paliperidone palmitate. Using the program administrative files (December 2010-April 2014), 9354 patients whose HCP ordered paliperidone palmitate were included. Patient demographics, clinical characteristics, and request of JC program offerings were reported overall, and compared between patients requesting the injection center versus those who did not. Medication adherence based on the first 6 months of treatment while in the program and defined as achieving ?80% proportion of days covered (PDC) was measured for patients receiving ?2 paliperidone palmitate injections (n = 2659). Logistic models evaluated the association between requests for injection centers on medication adherence. Mean age of program enrollees was 40.6 (standard deviation = 13.9 years), 59.3% were men, and 42.5% were Medicare covered. While in the program, 79.9% did not experience a medication gap of ?7 weeks and 87.0% achieved adherence. Injection center request was associated with medication adherence (adjusted odds ratio (aOR) ?5 months: 0.03; 95% confidence interval (CI): 0.02-0.05; ?6 months: aOR: 4.16; 95% CI: 2.72-6.36). The data sources used were designed for program implementation and not for research purposes. The high percentage of patients requesting injection center support and medication shipment in addition to other insurance-related program offerings signals the need for and value of a comprehensive support program for patients seeking LAI therapy. Providing patients with the option of alternative and more conveniently located injection centers may help them start and maintain their treatment. |
| SCZ Keywords | schizophrenia, schizophrenic |