Antipsychotic medications are effective in the treatment of psychotic disorders. Monotherapy (MT) with antipsychotics is consistently recommended as the treatment of choice by several guidelines yet antipsychotic polypharmacy (APP) is widespread in clinical practice. The objectives of this study were to evaluate the incidence of APP, identify predictors of APP, and compare adherence, health resource utilization, and costs between patients on MT and APP using prescription and medication claims from Texas Medicaid (2006 to 2011). Patients newly initiated on antipsychotics were followed for 12 months and categorized into the APP (exposure to two or more antipsychotics for a defined time interval) and MT (no evidence of APP during the study period) groups. This sample of patients was used to evaluate incidence and predictors of APP and compare medication adherence and persistence between the MT and APP groups using multiple, logistic, and Cox proportional hazards regressions. Patients in the MT and APP groups were then matched based on their duration of exposure to antipsychotics and all-cause healthcare utilization and costs were compared using logistic and generalized linear models regression (negative binomial, Poisson, and gamma). Regression analyses for patients matched on duration of antipsychotic exposure accounted for the correlation between matched pairs. The incidence of APP was 5.4%. Several demographic, clinical, physician, and prior utilization characteristics were associated with APP. Medication adherence and persistence were better in the APP group. Length of hospital stay and medical, drug, and total costs were higher for the APP group. Sensitivity analyses were conducted for psychiatric-related costs and varied overlap and gap periods. The results for most of the sensitivity analyses were similar to the base case. Patients prescribed APP had higher medical, drug and total costs and also higher healthcare utilization i.e. increased drug costs were not offset by decreased medical costs. Long-term APP raises concern as state Medicaid agencies are allocating their limited resources to this expensive treatment which has very scarce data supporting its use. More effectiveness research on APP is needed to help provide prescription guidance to clinicians for patients who do not respond well to treatment with a single antipsychotic. / text

Rheumatoid arthritis (RA) is a progressive autoimmune disorder of joints that is associated with high health care costs and yet lacks guidance on how early to initiate biologic disease-modifying antirheumatic drugs (DMARDs), a class of medications that is the major cost driver in RA management. The main purpose of this study was to examine patient socio-demographics, medication use patterns, and clinical characteristics associated with initiation of biologic DMARDs. This was a retrospective study using Texas Medicaid prescription and medical claims database during the study period of July 1, 2003 – December 31, 2010. Patients (18 – 63 years) with an RA diagnosis (ICD-9-CM code 714.xx), no non-biologic DMARD or biologic DMARD use during the pre-index period, and a minimum of 2 prescription claims for the same non-biologic DMARD during the post-index period were included in the study. The primary study outcomes were time to initiation of biologic DMARDs and likelihood of initiating biologic DMARDs. There was a total of 2,714 subjects included in the study. The majority had claims for pain medications (92.4%), glucocorticoids (64.9%), and non-biologic DMARD monotherapy (86.4%); while 24.3% initiated on biologic DMARDs and 58.9% had a Charlson Comorbidity Index (CCI) score=1. Compared to time to initiation (days) of biologic DMARDs for methotrexate (539.7±276.9) users, it was longer for sulfasalazine (670.2±167.8) and hydroxychloroquine (680.2±158.7) users and similar to leflunomide users (541.6±286.5; p<0.0001). There were no significant differences in time to initiation between non-biologic DMARD mono vs. dual therapy. Younger age, glucocorticoid use, methotrexate user (vs. sulfasalazine, hydroxychloroquine users), and non-biologic DMARD monotherapy user (vs. dual therapy user) were significantly associated with higher likelihood to initiate biologic DMARDs. In conclusion, age, glucocorticoid use, non-biologic DMARD type and therapy were significant factors associated with initiation of biologic DMARDs. Healthcare providers and Texas Medicaid should recognize these potential driving factors and take efforts to achieve optimal therapy for RA patients through thorough RA medication evaluation, well-structured RA monitoring programs, and patient education. / text

The present study is a retrospective cohort analysis which sought to examine adherence to medications used in managing painful diabetic peripheral neuropathy (PDPN) and to determine their association with oral antidiabetic (OAD) medication adherence using the Texas Medicaid prescription claims database. The study objectives were to: 1) provide a description of PDPN and OAD medication use among the study subjects; 2) determine if PDPN medication adherence differs among individual PDPN agents (i.e., tricyclic antidepressants, gabapentin, pregabalin and duloxetine); 3) determine if pre-index OAD and post-index OAD medication adherence differs among mono, dual, and triple OAD therapies; and 4) determine if PDPN medication adherence is related to post-index OAD medication adherence while controlling for covariates. Study participants were adult (≥18 years) Medicaid beneficiaries prescribed OAD and PDPN medications. The index date was the first PDPN prescription. Data were extracted from June 1, 2003 to October 31, 2009 and prescription claims were analyzed over an 18-month study period (i.e., 6 months pre-index and 12 months post index period). Medication possession ratio (MPR) was used as a proxy measure of medication adherence. An MPR less than 80 percent was regarded as being non-adherent to prescribed medication, while an MPR greater than or equal to 80 percent was regarded as being adherent to prescribed medication. Objective 1 was addressed using descriptive statistics (i.e., mean, standard deviation, frequency). Univariate analysis (ANOVA) was employed to address Objectives 2 and 3. Multivariate analyses (i.e., multiple linear regression and logistic regression) were conducted to address Objective 4. For the logistic regression MPR was dichotomized at the cut-off value of 80 percent. A total of 4,277 patients met the study’s inclusion criteria. The overall mean MPR (±SD) for PDPN medications was 75.4 percent (±23.9). Mean MPR (±SD) was highest for duloxetine (85.6% ±18.2) and was lowest for pregabalin (69.4% ±24.9). Mean MPR differed significantly among individual PDPN medications (p<0.0001). The overall mean MPR (±SD) for OAD medications in the pre and post-index period was 73.0 percent (±24.3) and 64.5 percent (±25.6) respectively. In both pre and post-index periods, mean MPR differed significantly among mono, dual, and triple OAD therapies (p<0.0001). In the pre-index period, mean MPR (±SD) was highest for monotherapy users (75.4% ±24.7) and was lowest for triple therapy users (63.9% ±22.9). Similarly, mean MPR (±SD) was highest for monotherapy users (69.0% ±26.1) and was lowest for triple therapy users (52.9% ±21.8) in the post-index period. After controlling for the covariates, PDPN adherence (i.e., MPR) was statistically significant (p<0.0001) and positively related to post-index OAD adherence (i.e., MPR). PDPN patients who were non-adherent (i.e., MPR<80%) to their PDPN medications (or neuropathic pain medications), compared to those who were adherent (MPR≥80%), were significantly less likely to be adherent to their OAD medications [Odds Ratio (OR) = 0.626, 95% CI=0.545-0.719]. In addition, post-index OAD adherence (i.e., MPR) did not differ significantly (p>0.05) when pregabalin, duloxetine and gabapentin users were individually compared to tricyclic antidepressants users. In conclusion, PDPN patients who were adherent (i.e., MPR≥80%) to their PDPN medications, compared to those who were not adherent (i.e., MPR<80%), were more adherent to their OAD medications. Also, adherence to OAD medications was independent of the type of PDPN medication used. PDPN patients need to be educated regularly that neuropathic pain medications only relieve the pain associated with the neuropathy but achieving adequate glycemic control remains the only established approach for slowing down the progression of the neuropathy and other complications associated with the diabetes. / text