Bong-l Chu

Effectiveness of antiepileptic drug combination therapy for partial-onset seizures based on mechanisms of action.

IMPORTANCE To our knowledge, the current study is the first to describe antiepileptic drug (AED) combination therapy patterns according to their mechanism of action (MOA) in a real-world setting and to evaluate the differences in outcomes comparing different-MOA combination therapy with same-MOA combination therapy for patients with partial-onset seizure. OBJECTIVE To compare treatment persistence and health care use with AED combinations categorized by MOA in patients with partial-onset seizures. DESIGN, SETTING, AND PARTICIPANTS Using the Truven Health MarketScan Commercial Claims Database containing 96 million covered lives from July 1, 2004, through March 31, 2011, adults with concomitant use of 2 different AEDs and a recent partial-onset seizure diagnosis were selected. Antiepileptic drugs were categorized by MOA: sodium channel blockers (SC), gamma-aminobutyric acid analogs (G), synaptic vesicle protein 2A binding (SV2), and multiple mechanisms (M). Patients were assigned a combination category based on their concomitant AED use. MAIN OUTCOMES AND MEASURES Treatment persistence was measured from the start of AED combination therapy until the end of the combination. Health care resource use was measured during the combination treatment duration. Multivariate analyses evaluated AED discontinuation risk and health care use according to MOA combinations. RESULTS Distribution of 8615 selected patients by combination was 3.3% for G+G, 7.5% for G+SV2, 8.6% for G+M, 13.9% for SC+SC, 19.0% for G+SC, 21.5% for SC+M, and 26.3% for SC+SV2. The same-MOA (G+G and SC+SC) combinations had the shortest persistence (mean [SD], 344 [345] days and 513 [530] days, respectively) and greater hazard of discontinuation compared with different-MOA combinations. Patients with different-MOA G combinations had a significantly lower risk for inpatient admission (odds ratio, 0.716; 95% CI, 0.539-0.952; P = .02) compared with G+G combinations. Patients with different-MOA SC combinations had significantly lower risks for emergency department visits (odds ratio, 0.853; 95% CI, 0.742-0.980; P = .03) compared with SC+SC combinations. CONCLUSIONS AND RELEVANCE The findings suggest that AED combinations with different MOAs have greater effectiveness as measured by treatment persistence and lower risks for hospitalization and emergency department visits. Further research is needed to more fully understand the role of the MOA in achieving optimal outcomes.

Risk of infections in rheumatoid arthritis patients switching from anti-TNF agents to rituximab, abatacept, or another anti-TNF agent, a retrospective administrative claims analysis

OBJECTIVE This study compared the incidence and hazard of ICD-9-CM-coded infections and severe infections in rheumatoid arthritis (RA) patients treated with subsequent-line (SL) BIOs (BIO) after switching from first-line (FL) anti-TNF therapy (anti-TNF). METHODS Retrospective analysis of a large U.S. claims database. RA patients initiating an FL anti-TNF between 1/1/2004 and 3/31/2010 were identified and followed forward in time to capture all SL BIO episodes through 3/31/2010. SL BIO episodes were classified into: abatacept, adalimumab, etanercept, infliximab, or rituximab. Multivariate mixed-effects survival models compared the hazard of infections and severe infections across the SL BIO episodes with adjustment for demographic and clinical confounders. RESULTS In total, 4332 SL BIO episodes were identified: mean age 55 years; 80% female. In adjusted analyses: when compared to rituximab, the hazard of all infections was significantly higher for adalimumab (hazard ratio [HR] = 1.31, 95% confidence interval [CI] = 1.09-1.55), etanercept (HR = 1.44, 95% CI = 1.20-1.72), and infliximab (HR = 1.30, 95% CI = 1.07-1.57), and insignificantly different for abatacept (HR = 1.18, 95% CI = 0.98-1.41); when compared to rituximab, the hazard of severe infection was significantly higher for infliximab (HR = 1.62, 95% CI = 1.03-2.55), and insignificantly different for abatacept (HR = 1.21, 95% CI = 0.78-1.88), adalimumab (HR = 1.10, 95% CI = 0.72-1.68), and etanercept (HR = 1.27, 95% CI = 0.83-1.95). CONCLUSIONS In RA patients treated with SL BIO, a 30-44% higher hazard of all infection was observed in anti-TNFs versus rituximab with a 62% higher hazard of severe infection observed in infliximab versus rituximab. This study used a non-randomized, observational design and is therefore subject to confounding from unmeasured factors that influence both treatment choice and infection risk.

Fractures in women treated with raloxifene or alendronate: a retrospective database analysis.

BackgroundRaloxifene and alendronate are anti-resorptive therapies approved for the prevention and treatment of postmenopausal osteoporosis. Raloxifene is also indicated to reduce the risk of invasive breast cancer in postmenopausal women with osteoporosis and in postmenopausal women at high risk of invasive breast cancer. A definitive study comparing the fracture effectiveness and rate of breast cancer for raloxifene and alendronate has not been published. The purpose of this retrospective cohort study was to evaluate fracture and breast cancer rates among patients treated with raloxifene or alendronate.MethodsFemales ≥45 years who initiated raloxifene or alendronate in 1998–2006 Truven Health Analytics MarketScan® Databases, had continuous enrollment 12 months prior to and at least 12 months after the index date, and had a treatment medication possession ratio ≥80% were included in this study. Rates of vertebral and nonvertebral fractures and breast cancer during 1, 3, 5, 6, 7, and 8 years of treatment with raloxifene or alendronate were evaluated. Fracture rates were adjusted for potential treatment bias using inverse probability of treatment weights. Multivariate hazard ratios were estimated for vertebral and nonvertebral fractures.ResultsRaloxifene patients had statistically significantly lower rates of vertebral fractures in 1, 3, 5, and 7 years and for nonvertebral fractures in 1 and 5 years. There were no statistically significant differences in the adjusted fracture rates between raloxifene and alendronate cohorts, except in the 3-year nonvertebral fracture rates where raloxifene was higher. Multivariate hazard ratios of raloxifene versus alendronate cohorts were not significantly different for vertebral and nonvertebral fracture in 1, 3, 5, 6, 7, and 8 years. Unweighted and weighted breast cancer rates were lower among raloxifene recipients.ConclusionsPatients treated with alendronate and raloxifene had similar adjusted fracture rates in up to 8 years of adherent treatment, and raloxifene patients had lower breast cancer rates.

Comparative Incidence and Health Care Costs of Medically Attended Adverse Effects among U.S. Medicaid HIV Patients on Atazanavir- or Darunavir-Based Antiretroviral Therapy

OBJECTIVES This is the first study to compare the incidence and health care costs of medically attended adverse effects in atazanavir- and darunavir-based antiretroviral therapy (ART) among U.S. Medicaid patients receiving routine HIV care. METHODS This was a retrospective study using Medicaid administrative health care claims from 15 states. Subjects were HIV patients aged 18 to 64 years initiating atazanavir- or darunavir-based ART from January 1, 2003, to July 1, 2010, with continuous enrollment for 6 months before (baseline) and 6 months after (evaluation period) ART initiation and 1 or more evaluation period medical claim. Outcomes were incidence and health care costs of the following medically attended (International Classification of Diseases, Ninth Revision, Clinical Modification-coded or treated) adverse effects during the evaluation period: gastrointestinal, lipid abnormalities, diabetes/hyperglycemia, rash, and jaundice. All-cause health care costs were also determined. Patients treated with atazanavir and darunavir were propensity score matched (ratio = 3:1) by using demographic and clinical covariates. Multivariable models adjusted for covariates lacking postmatch statistical balance. RESULTS Propensity-matched study sample included 1848 atazanavir- and 616 darunavir-treated patients (mean age 41 years, 50% women, 69% black). Multivariable-adjusted hazard ratios (HRs) (for darunavir, reference = atazanavir) and per-patient-per-month health care cost differences (darunavir minus atazanavir) were as follows: gastrointestinal, HR = 1.25 (P = 0.04),

Cost comparison of drug–drug and drug–condition interactions in patients with painful diabetic peripheral neuropathy treated with pregabalin versus duloxetine

43 (P = 0.13); lipid abnormalities, HR = 1.38 (P = 0.07),

Retrospective study comparing healthcare costs and utilization between commercially insured patients with type 2 diabetes mellitus who are newly initiating exenatide once weekly or liraglutide in the United States

3 (P = 0.88); diabetes/hyperglycemia, HR = 0.84 (P = 0.55),

Potential drug-drug and drug-condition interactions among fibromyalgia patients initiating pregabalin or duloxetine: prevalence and health care expenditure impact.

13 (P = 0.69); and rash, HR = 1.11 (P = 0.23),

Estimation of Total Incremental Health Care Costs in Patients With Atrial Fibrillation in the United States

0 (P = 0.76); all-cause health care costs were

Retrospective Study of Adherence to Glucagon-like Peptide-1 Receptor Agonist Therapy in Patients with Type 2 Diabetes Mellitus in the United States

1086 (P<0.001). Too few instances of jaundice (11 in atazanavir and 1 in darunavir) occurred to support multivariable modeling. CONCLUSIONS Medication tolerability can be critical to the success or failure of ART. Compared with darunavir-treated patients, atazanavir-treated patients had significantly fewer instances of medically attended gastrointestinal issues and more instances of jaundice and incurred significantly lower health care costs.

Association between prescription cost sharing and adherence to initial combination antiretroviral therapy in commercially insured antiretroviral-naïve patients with HIV.

PURPOSE The frequency and financial impact of potential drug-drug interactions (DDIs) and drug-condition interactions (DCIs) in patients with painful diabetic peripheral neuropathy (DPN) treated with either pregabalin or duloxetine were compared. METHODS This retrospective cohort study was conducted using a large U.S. administrative claims database. Patients selected for study inclusion had a diagnosis of DPN and were newly initiated on either pregabalin or duloxetine between July 1, 2008, and October 1, 2010. Data on potential DDIs and DCIs were collected. Health care costs were measured as the sum of gross covered payments for all medical and prescription claims incurred during the six months after the index date. RESULTS The study sample comprised 2499 pregabalin users and 1354 duloxetine users. Among pregabalin users, 48 (1.8%) had at least one potential pregabalin DCI; none had potential pregabalin DDIs. Among duloxetine users, 966 (71%) had at least one potential duloxetine DDI or DCI. The frequencies of potential DDIs and DCIs differed significantly between pregabalin and duloxetine users (p < 0.001). Potential duloxetine DDIs and DCIs were associated with a significant increase in mean health care costs in duloxetine users (p = 0.002). Potential pregabalin DDIs and DCIs were not associated with additional health care costs in pregabalin users. CONCLUSION Among patients with painful DPN treated with either pregabalin or duloxetine, the frequency of potential duloxetine DDIs and DCIs was substantially higher than that of pregabalin. Potential DDIs and DCIs were associated with significantly increased health care costs in duloxetine users.