Impact of two sequential drug cost-sharing policies on the use of inhaled medications in older patients with chronic obstructive pulmonary disease or asthma

doi:10.1016/j.clinthera.2006.06.007

Clinical Therapeutics

Volume 28, Issue 6, June 2006, Pages 964-978

https://doi.org/10.1016/j.clinthera.2006.06.007 Get rights and content

Background:

Evaluations of drug cost-sharing policies within the same population are needed for a fair comparison of different options.

Objective:

The aim of this work was to analyze the impact of 2 changes in a public drug insurance plan on the use of inhaled medications in British Columbia (BC), Canada.

Methods:

Data for the period from 1997 to 2004 were used to assess whether changes in the use of steroid, β₂-agonist, and anticholinergic inhalers were associated with insurance-plan changes in a large, natural experiment involving all BC residents aged ≥65 years. The 3 sequential policies included full coverage, fixed copayments at the beginning of 2002, and 25% coinsurance with an income-based deductible beginning May 1, 2003. Linkable prescription, physician billing, hospitalization, and mortality records were obtained from the BC Ministry of Health Services. From the total population of residents aged ≥65 years, we extracted data for all patients to whom inhaled steroids, β₂-agonists, or anticholinergics were dispensed on or after January 1, 1997. Multivariable linear regression was used to estimate inhaler use during a 60-month baseline period and during implementation of the subsequent copayment and coinsurance plus deductible policies. We used logistic regression to identify predictors of initiation and cessation use of inhaled medications among older patients.

Results:

Use declined for inhaled steroids (−12.3%; P < 0.001), inhaled anticholinergics (−12.2%; P < 0.001), and inhaled β₂-agonists (−5.8%; P < 0.001). Patients with new diagnoses of asthma or chronic obstructive pulmonary disease were 25% (95% CI, 14%–31%) less likely to initiate treatment with inhaled steroids when covered by the copayment or coinsurance plus deductible policies than when they had full coverage. Chronic users of inhaled steroids were 47% (95% CI, 40%–55%) more likely to cease treatment when they were covered by the copayment policy and 22% (95% CI, 15%–29%) more likely to cease when covered by the coinsurance plus deductible policy than when they had full coverage.

Conclusions:

The copayment and coinsurance plus deductible policies were associated with significant reductions in use of inhaled medications, mostly due to decreased initiation and increased cessation rates. However, the consequences of these policies on health outcomes have not yet been determined.

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The Associations of Prescription Drug Insurance and Cost-Sharing With Drug Use, Health Services Use, and Health: A Systematic Review of Canadian Studies
2023, Value in Health
In Canada, public insurance for physician and hospital services, without cost-sharing, is provided to all residents. Outpatient prescription drug coverage, however, is provided through a patchwork system of public and private plans, often with substantial cost-sharing, which leaves many underinsured or uninsured.
We conducted a systematic review to examine the association of drug insurance and cost-sharing with drug use, health services use, and health in Canada. We searched 4 electronic databases, 2 grey literature databases, 5 specialty journals, and 2 working paper repositories. At least 2 reviewers independently screened articles for inclusion, extracted characteristics, and assessed risk of bias.
The expansion of drug insurance was associated with increases in drug use, individuals who reported drug insurance generally reported higher drug use, and increases in and higher levels of drug cost-sharing were associated with lower drug use. Although a number of studies found statistically significant associations between drug insurance or cost-sharing and health services use, the magnitudes of these associations were generally fairly small. Among 5 studies that examined the association of drug insurance and cost-sharing with health outcomes, 1 found a statistically significant and clinically meaningful association. We did not find that socioeconomic status or sex were effect modifiers; there was some evidence that health modified the association between drug insurance and cost-sharing and drug use.
Increased cost-sharing is likely to reduce drug use. Universal pharmacare without cost-sharing may reduce inequities because it would likely increase drug use among lower-income populations relative to higher-income populations.
National Trends and Disparities in Health Care Access and Coverage Among Adults With Asthma and COPD: 1997-2018
2021, Chest
Racial and ethnic as well as economic disparities in access to care among persons with asthma and COPD have been described, but long-term access trends are unclear.
Have health coverage and access to care and medications among adults with airways disease improved, and have disparities narrowed?
Using the 1997 through 2018 National Health Interview Survey, we examined time trends in health coverage and the affordability of medical care and prescription drugs for adults with asthma and COPD, overall and by income and by race and ethnicity. We performed multivariate linear probability regressions comparing coverage and access in 2018 with that in 1997.
Our sample included 76,843 adults with asthma and 30,548 adults with COPD. Among adults with asthma, lack of insurance rose in the first decade of the twenty-first century, peaking with the Great Recession, but fell after implementation of the Affordable Care Act (ACA). From 1997 through 2018, the uninsured rate among adults with asthma decreased from 19.4% to 9.6% (adjusted 9.27 percentage points; 95% CI, 7.1%-11.5%). However, the proportions delaying or foregoing medical care because of cost or going without medications did not improve. Racial and ethnic as well as economic disparities present in 1997 persisted over the study period. Trends and disparities among those with COPD were similar, although the proportion going without needed medications worsened, rising by an adjusted 7.8 percentage points.
Coverage losses among persons with airways disease in the first decade of the twenty-first century were reversed by the ACA, but neither care affordability nor disparities improved. Further reform is needed to close these gaps.
POINT: Should Pulmonary/ICU Physicians Support Single-payer Health-care Reform? Yes
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Measuring drug exposure: Concordance between defined daily dose and days' supply depended on drug class
2016, Journal of Clinical Epidemiology
Citation Excerpt :
In a comparison of the DDD with other measures such as the MMD and the PDD, Merlo et al. [6] found that the DDD emerged as being the superior measure. Although not the intended purpose of the DDD, many studies in European databases and others around the world have used the DDD to estimate individual patients' exposure duration [9–13]. It is not known to what extent exposure duration assessed using the DDD methodology corresponds to duration assessed using the days' supply.
To determine the concordance between two methods to measure drug exposure duration from pharmacy claim data.
We conducted a cohort study using 2002–2007 US Medicaid data. Initiators of eight drug groups were identified: statins, metformin, atypical antipsychotics, warfarin, proton pump inhibitors (PPIs), angiotensin-converting enzyme (ACE) inhibitors, nonsteroidal anti-inflammatory drugs (ns-NSAIDs), and coxibs. For each patient, we calculated two measures of exposure duration using (1) observed days' supply available in US pharmacy claims and (2) the World Health Organisation's Defined Daily Dose (DDD) methodology. We used Wilcoxon signed rank tests to compare medians and Spearman correlations to assess correlation between the two measures.
Cohort sizes ranged from 143,885 warfarin users to >3,000,000 ns-NSAID users. Similar median exposure durations were observed for ACE inhibitors (70 days vs.75 days), PPIs (44 days vs. 45 days), and coxibs (44 days vs. 45 days). The DDD method overestimated exposure duration for ns-NSAIDs and underestimated for the remaining drug groups, relative to days' supply. Spearman correlation coefficients ranged from 0.2 to 0.8.
Using DDDs to estimate drug exposure duration can result in misclassification. The magnitude of this misclassification might depend on doses used which can vary according to factors such as local prescribing practices, renal function, and age.
Trends in health care utilization in British Columbia following public coverage for tiotropium
2011, Value in Health
To examine the use and cost of health-care services in British Columbia, Canada, before and after public drug coverage for tiotropium bromide.
A time series analysis was performed using data from British Columbia's centralized administrative health-care databases. Linear regression on data from a stable 3-year prepolicy period was used to predict future use of inhaled anticholinergic (IAC) medications, visits to physicians, emergency hospitalizations, and costs. For each use measure, we estimated the policy effect as the difference between observed use in the postpolicy period and predicted use obtained from the prepolicy period.
In total, over the 2.5-year period after public coverage, tiotropium use increased by 24.4% more than predicted (95% confidence interval [CI] 23.9%–24.8%). Visits to physicians were unchanged, but there were between 596 and 948 more emergency admissions for chronic obstructive pulmonary disease, and between 582 and 1940 more hospital admissions of any kind than were predicted from prepolicy data. Total cost of inhaled IAC medications increased slightly more than predicted, by between an additional CDN$1.30 million and CDN$1.71 million, but total out-of-pocket spending by patients on IAC medications was reduced by between CDN$2.83 million and CDN$3.11 million because of public coverage. Hospital costs were between CDN$3.88 million and CDN$12.93 million greater than anticipated based on prepolicy data.
Public drug plan coverage for tiotropium in British Columbia reduced out-of-pocket costs for patients and their private insurers. Before versus after time series analysis did not show a reduction in hospitalizations or physician visits, or costs associated with those services.
Relationship of asthma management, socioeconomic status, and medication insurance characteristics to exacerbation frequency in children with asthma
2011, Annals of Allergy, Asthma and Immunology
Citation Excerpt :
When consumers must pay a percentage of the total drug cost (coinsurance), there is an incentive to forgo more costly medications or to substitute them with cheaper drugs. When a British Columbia drug program changed from zero cost-sharing to fixed copayments and then to 25% coinsurance with an income-indexed deductible, seniors' use of inhaled corticosteroids, inhaled anticholinergics, and inhaled β-agonists all decreased.34 Similarly, a 37% reduction in monthly consumption of inhaled corticosteroids was found in social assistance beneficiaries after a change in Quebec's drug plan from zero cost-sharing to 25% coinsurance plus a quarterly deductible of Can$25.35
Less than 25% of asthmatic children are well controlled.
To identify factors associated with asthma exacerbation causing emergency department (ED) visits or hospitalizations related to health status, socioeconomic status (SES), and drug insurance.
In this retrospective cohort study, complete data were collected on 490 asthmatic children regarding demographics, SES, drug plan characteristics, health status, health resource use, and symptoms. Interview data were linked to administrative data on asthma ED visits and hospitalizations occurring in the following year. Multiple Poisson regression identified independent variables associated with ED visits or hospitalizations in the full cohort and in a subgroup with prescription drug insurance.
Younger age, previous emergency visits, nebulizer use, pet ownership, and receipt of asthma education but not an action plan were significantly associated with more frequent exacerbations. In the full cohort, children with high income adequacy had 28% fewer exacerbations than did children with low income adequacy. In the subgroup with drug insurance, girls had 26% fewer exacerbations than did boys, and children with food, drug, or insect allergies had 52% more exacerbations than did children without allergies. Children of families with annual insurance deductibles greater than $90 had 95% fewer exacerbations. Every percentage increase in the proportion of income spent out-of-pocket on asthma medications was associated with a 14% increase in exacerbations.
Asthma history, disease management factors, and SES were associated with exacerbations requiring urgent care. In families with drug plans, the magnitude of asthma medication cost-sharing as a proportion of household income, rather than income alone, was significantly associated with exacerbations.

View all citing articles on Scopus

^*: Current affiliation: Pharmacoepidemiology Group, Therapeutics Initiative, University of British Columbia, Vancouver, British Columbia, Canada.

View full text

Impact of two sequential drug cost-sharing policies on the use of inhaled medications in older patients with chronic obstructive pulmonary disease or asthma

Background:

Objective:

Methods:

Results:

Conclusions:

Chest

J Clin Epidemiol

Outcomes of reference pricing for angiotensin-converting-enzyme inhibitors

N Eng J Med

Impact of reference-based pricing of nitrates on the use and costs of anti-anginal drugs

CMAJ

Clinical and economic consequences of reference pricing for dihydropyridine calcium channel blockers

Clin Pharmacol Ther

Impact of reference-based pricing for histamine-2 receptor antagonists and restricted access for proton pump inhibitors in British Columbia

CMAJ

Clinical and economic consequences of a reimbursement restriction of nebulised respiratory therapy in adults: Direct comparison of randomised and observational evaluations

BMJ

Effects of Medicaid drug-payment limits on admission to hospitals and nursing homes

N Engl J Med.

Adverse events associated with prescription drug cost-sharing among poor and elderly persons

JAMA

Income-based drug benefit policy: Impact on receipt of inhaled corticosteroid prescriptions by Manitoba children with asthma

CMAJ

The effect of incentive-based formularies on prescription-drug utilization and spending

N Engl J Med

Effect of a three-tier prescription copay on pharmaceutical and other medical utilization

Med Care

Three-tiered-copayment drug coverage and use of nonsteroidal anti-inflammatory drugs

Arch Intern Med

Principles of Economics, An Introductory Volume

Your Fair Pharmacare Coverage

Trends and determinants of prescription drug expenditures in the elderly: Data from the British Columbia Pharmacare Program

Inquiry