Antiretroviral Treatment Gaps and Adherence Among People with HIV in the U.S. Medicare Program.

Approximately one-quarter of people with HIV (PWH) in the U.S. receive coverage through the Medicare program; however, no prior real-world study has examined antiretroviral therapy (ART) gaps and adherence and associated factors in this population. This retrospective cohort analysis used 2013-2018 national Medicare fee-for-service claims data to identify all PWH initiated on a new ART regimen including protease inhibitors [PI], non-nucleoside reverse transcriptase inhibitors [NNRTIs], or integrase strand transfer inhibitors [INSTIs] between 1/1/2014 and 12/31/2017. Study outcomes included ART adherence (based on proportion of days covered [PDC]), continuous treatment gaps ranging from 1 to 6 days to ≥ 180 days, and discontinuation (continuous gap ≥ 90 days) in the 12-month follow-up period. Multivariable regressions were used to assess factors associated with ART adherence and discontinuation. The final sample included 48,627 PWH (mean age: 54.5 years, 74.4% male, 47.5% White, 89.8% disabled). Approximately 53.0% of PWH had a PDC ≥ 0.95, 30.2% had a PDC between 0.70 and < 0.95, and 16.8% had PDC < 0.70. Treatment gaps of at least ≥ 7-days (55.2%) and ≥ 30-days (26.2%) were common and 10.1% PWH discontinued treatment. Younger age, female sex, Black race, higher comorbidity score, mental health conditions, and substance use disorder were associated with higher odds of lower adherence and discontinuation (all p-values < 0.05). In conclusion, suboptimal adherence and treatment gaps in ART use were commonly observed among PWH in Medicare. Interventions and policies to mitigate barriers to adherence are urgently needed in this population to both improve their survival and increase the potential for ending the HIV epidemic in the US.

Low Sustainment of High-Dose Oral Medication Regimens for Advanced Parkinson's Disease in Medicare Beneficiaries.

BACKGROUND: Increasing doses of oral antiparkinson medications are indicated in advanced Parkinson's disease (PD), but little is known about sustainment of high-dose regimens. OBJECTIVE: To investigate sustainment of high-dose oral medication regimens in Medicare beneficiaries with incident advanced PD. METHODS: This retrospective cohort study utilized 100%fee-for-service Medicare claims from 2011-2013. We identified advanced PD using a pharmacy claims-based proxy and selected patients who initiated a new high-dose oral medication regimen (daily levodopa equivalent dose [LED] >1000 mg/day for ≥30 days) in 2012. In the following 12 months, we examined: 1) annual proportion of days covered (PDC)≥0.80 and 2) presence of a ≥ 90 day continuous gap at varying dosage thresholds: the initial >1000 mg/day, >800 mg/day, >500 mg/day, or >0 mg/day. RESULTS: We identified 9,405 patients with advanced PD (mean age 77.4 [SD 6.8] years; 53%men). Only 5%maintained a regimen of >1000 mg/day at PDC ≥0.80; 75% had a ≥ 90-day gap in that dosage level. At a dosage threshold of >800 mg/day, 20% had a PDC ≥0.80 and 53% had a ≥ 90-day gap; at >500 mg/day, 56% had a PDC ≥0.80 and 19%had a ≥ 90-day gap; and at >0 mg/day (any dose), 76% had a PDC ≥0.80 and only 10%had a≥90-day gap. CONCLUSION: Few patients with advanced PD sustained a high-dose oral medication regimen in the year following initiation, but most sustained a substantially lower-dose regimen. Strategies to improve advanced PD treatment are needed.

Burden of Parkinson's Disease by Severity: Health Care Costs in the U.S. Medicare Population.

BACKGROUND: Current understanding of the health care costs of Parkinson's disease (PD) and the incremental burden of advanced disease is incomplete. OBJECTIVES: The aim of this study was to assess the direct economic burden associated with advanced versus mild/moderate PD in a prevalent national sample of elderly U.S. Medicare beneficiaries with a PD diagnosis. METHODS: Analyzing 100% fee-for-service Medicare claims from 2013, we defined advanced PD with a medication-based algorithm and calculated all-cause and PD-related costs for the overall sample and by disease severity. We measured primary PD-related costs (based on claims with a primary diagnosis of PD) and any PD-related costs (based on claims with PD in any diagnostic field). Generalized linear models were used to estimate risk-adjusted mean cost differences between the advanced and mild/moderate PD groups for the calendar year. RESULTS: The final sample (N = 144,703) had mean observed all-cause, primary PD-related, and any PD-related costs of $23,041 (SD, $34,045), $3429 (SD, $7431), and $9924 (SD, $22,140), respectively. Twenty percent of patients were classified as advanced PD. Costs varied substantially; any PD-related mean costs were $483 for the lowest patient decile (which included 1% of the advanced group) and $48,145 for the highest decile (which included 15% of the advanced group). Incremental risk-adjusted costs of advanced PD were $5818 (95% confidence interval [CI]: $5411-$6225) for all-cause costs, $3644 (95% CI: $3484-$3806) for primary PD-related costs, and $6088 (95% CI: $5779-$6398) for any PD-related costs. CONCLUSIONS: Elderly Medicare beneficiaries with PD had substantial variation in PD-related costs. Advanced PD was associated with a larger economic burden than mild/moderate PD. © 2020 International Parkinson and Movement Disorder Society.

Disease-Modifying Therapy Adherence and Associated Factors in a National Sample of Medicare Patients With Multiple Sclerosis.

OBJECTIVES: Disease-modifying therapies (DMTs) reduce relapse rates and disability progression for relapsing multiple sclerosis (MS). Although 25% to 30% of all US patients with MS are Medicare beneficiaries, limited information exists on this population. This is the first study using national Medicare data to (1) describe characteristics of patients with MS using DMTs, (2) estimate adherence to DMTs over a 1-year and 3-year follow-up, and (3) examine factors associated with DMT adherence. METHODS: This retrospective claims analysis used 2011-2014 100% Medicare files. Monthly adherence to MS DMTs was defined as the proportion of days covered ≥0.80 with any DMT in each month for 1-year (n = 36 593) and 3-year (n = 17 599) follow-up samples of MS DMT users. Generalized estimating equation logistic regressions were used to estimate factors associated with adherence to DMTs. RESULTS: Over 90% of patients were eligible for Medicare owing to disability, and about three-quarters qualified for low-income subsidies. A downward trend in DMT adherence was observed over time in both samples. Monthly adherence dropped significantly between December of the prior year to January of the following year (from 76% to 65% in the 1-year follow-up sample and similar drops seen across all years in the 3-year follow-up sample). Multivariable regressions indicated characteristics such as being low-income, having a disability, and having high patient out-of-pocket DMT costs associated with poor adherence to DMTs. CONCLUSION: Our study provides important insights into the characteristics and DMT adherence of Medicare patients with MS and highlights the need for interventions and policies mitigating barriers to adherence in this population.

Use of a medication-based algorithm to identify advanced Parkinson's disease in administrative claims data: Associations with claims-based indicators of disease severity.

INTRODUCTION: Lack of a gold standard definition for advanced Parkinson's Disease (APD), coupled with absence of disease severity information in diagnostic codes, hinders use of large administrative databases for conducting population health and comparative effectiveness studies. METHODS: Using pharmacy claims data, we created an algorithm to identify APD: any 30-day average levodopa equivalent dose (LED) >1000 mg/day. Using 2013 100% U.S. Medicare claims, we applied this algorithm and used multivariate logistic regression to examine associations between assigned APD status and claims-based indicators of PD severity (any deep brain stimulation, fall, hallucinations, walker, wheelchair, specialty bed, dementia diagnosis, skilled nursing facility, hospice), adjusting for sociodemographic, clinical, and treatment characteristics. Levodopa >1000 mg/day, levodopa >800 mg/day and LED >800 mg/day were used in sensitivity analysis. RESULTS: In our sample (N = 144,703), 20% were assigned APD status based on the LED >1000 mg/day cut-off. This group had significantly higher odds of having each claims-based indicator, compared with those assigned mild-moderate PD status. Odds ratios were highest for indicators for any DBS (OR: 2.96; 95% CI:2.75-3.19) and specialty bed (OR:2.15, 95% CI: 1.99-2.32) and lowest for fall (OR:1.27; 95% CI:1.20-1.34) and dementia diagnosis (OR:1.21; 95% CI:1.18-1.25). Results based on alternative approaches were similar. CONCLUSIONS: Medicare patients classified as having APD via a pharmacy claims-based algorithm had higher odds of having claims-based clinical markers of APD, compared with patients categorized as having mild-moderate PD. This proxy strategy could facilitate future claims-based studies and warrants further refinement and validation using medical records or other clinical sources.

Early hypoglycaemia and adherence after basal insulin initiation in a nationally representative sample of Medicare beneficiaries with type 2 diabetes.

AIMS: To estimate risk factors associated with early hypoglycaemia and its impact on adherence to and persistence with therapy in Medicare Part D beneficiaries with type 2 diabetes who are initiating basal insulin (BI). MATERIALS AND METHODS: This retrospective analysis used a 5% sample of Medicare files from 2007-2013, identifying beneficiaries with type 2 diabetes initiating BI from 1 January 2008 to 31 December 2012. Early hypoglycaemia was defined as ≥1 hypoglycaemic event ≤6 months postindex. Outcomes included medication adherence and persistence over 12- and 36-month follow-up. Multivariable logistic and Cox regression analyses were conducted to examine factors associated with early hypoglycaemia and BI adherence/persistence. RESULTS: Of the 14 466 included patients, 1315 (9.1%) experienced hypoglycaemia ≤6 months after initiating BI. Factors associated with early hypoglycaemia were female sex (odds ratio [OR] 1.16 [95% confidence interval [CI] 1.02-1.32]), receipt of a low-income subsidy under Medicare Part D (OR 1.20 [95% CI 1.01-1.43]), high diabetes complication score index (OR 1.08 [95% CI 1.01-1.15]), and hypoglycaemia during the baseline period (OR 4.24 [95% CI 3.63-4.96]). At 12 months, patients with baseline hypoglycaemia were less likely to be adherent to (OR 0.81 [95% CI 0.70-0.93]) and more likely to discontinue (OR 1.33 [95% CI 1.07-1.66]) their insulin therapy. Results were similar at 36 months. CONCLUSIONS: Within 6 months of BI initiation, almost 1 in 10 Medicare Part D beneficiaries experienced hypoglycaemia. Early hypoglycaemia was associated with decreased adherence to BI treatment over 12- and 36-month follow-up.

Reducing out-of-pocket cost barriers to specialty drug use under Medicare Part D: addressing the problem of "too much too soon".

OBJECTIVES: Medicare Part D specialty drug users not qualifying for low-income subsidies (non-LIS beneficiaries) face high and variable cost sharing during the calendar year. We examined their out-of-pocket (OOP) cost patterns under the existing Part D cost-sharing policies and proposed changes to these policies. METHODS: Using 100% Medicare claims data from 2012, we examined mean annual and monthly OOP drug costs for Medicare Part D patients who were full-year users of Part D specialty drugs for rheumatoid arthritis (RA) (n = 1063), multiple sclerosis (MS) (n = 2256), or chronic myeloid leukemia (CML) (n = 1135) under existing policy. Using the same data, we simulated costs under both proposed Medicare Payment Advisory Commission (MedPAC) policy recommendations and our own recommendations. RESULTS: In 2012, our sample faced mean annual cumulative OOP drug costs (for all medications) of $3949 (RA), $5238 (MS), and $6322 (CML). Mean OOP costs were $977 (RA), $1613 (MS), and $2456 (CML) in January alone. A substantial proportion of total annual OOP prescription spending also occurred during the catastrophic coverage phase (RA: $1229 [31%]; MS: $2456 [47%]; CML: $3546 [56%]). Under proposed MedPAC changes, patients would have faced maximum annual OOP spending of $4700, but mean OOP costs in January and February would have been higher compared with the existing policy. Under our proposed strategy, OOP costs would have been spread evenly over 12 months (≤$392 per month). The potential incremental costs of our proposed strategy would have been $23.55 per non-LIS Part D beneficiary per year. CONCLUSIONS: The existing Part D cost-sharing structure creates a substantial financial burden for specialty drug users, especially early in the year. Implementing both annual and monthly OOP maximum spending limits would result in lower, more consistent OOP costs, potentially increasing patients' ability to access treatments for life-threatening, chronic, and rare diseases.

Impact of cost sharing on specialty drug utilization and outcomes: a review of the evidence and future directions.

OBJECTIVES: Specialty drugs often represent major medical advances for patients with few other effective options available, but high costs have attracted the attention of both payers and policy makers. We reviewed the evidence regarding the impact of cost sharing on utilization of specialty drugs indicated for rheumatoid arthritis (RA), multiple sclerosis (MS), and cancer, and on the use of nondrug medical services, health outcomes, and spending. STUDY DESIGN: Systematic review of Medline-indexed studies identified via an OVID search for articles published in English from 1995 to 2014, using combinations of terms for cost sharing and specialty drugs, and/or our 3 conditions of interest. We identified additional studies from reference lists. RESULTS: We identified 19 articles focusing on specialty drugs indicated for MS (n = 9), cancer (n = 8), and RA (n = 8). Studies examined prescription abandonment (n = 3), initiation or any utilization (n = 8), adherence (n = 9), persistence/discontinuation (n = 7), number of claims (n = 1), and drug spending (n = 1). Findings varied by disease, but generally indicated stronger effects for noninitiation or abandonment of a prescription at the pharmacy and somewhat smaller effects for refill behavior and drug spending once patients initiated therapy. Studies have not examined specialty tier cost sharing seen under Medicare Part D or health insurance exchanges, nor effects on medical utilization, spending, or health outcomes. CONCLUSIONS: Evidence to date generally indicates reductions in specialty drug utilization associated with higher cost sharing; effects have varied by type of disease and specialty drug use outcome. We draw upon our findings and the gaps in evidence to summarize future directions for research and policy.