The study, encompassing data from 2020 to 2023, analyzed the CPAP usage patterns of 132,492 adults diagnosed with OSA who received CPAP devices within the integrated Kaiser Permanente Southern California healthcare system. This unique setting is crucial to the study’s findings, as it maintained CPAP coverage for patients regardless of their initial adherence to the 90-day CMS benchmark. This contrasts sharply with many other healthcare systems where coverage can be terminated if patients do not meet these specific criteria.

Background: The CMS Adherence Mandate and its Critics

For years, CMS has mandated that Medicare beneficiaries using CPAP therapy for sleep apnea must demonstrate a minimum level of adherence within the first 90 days of treatment to maintain ongoing coverage. This requirement, often cited as using the device for at least four hours per night on at least 70% of nights, was intended to ensure that patients were actively benefiting from the therapy and that taxpayer funds were being used judiciously. However, the evidence base directly supporting this specific 90-day threshold as a definitive predictor of long-term success or the necessity for coverage cessation has been a subject of ongoing debate within the medical community.

Critics have argued that this rigid criterion fails to account for the complex nature of CPAP therapy initiation. For many patients, the initial weeks and months of CPAP use can be challenging, involving adjustments to mask fit, pressure settings, and overcoming the psychological hurdle of sleeping with a device. Factors such as discomfort, side effects, and lack of immediate symptom relief can contribute to initial difficulties in achieving high adherence rates. The CMS mandate, critics contend, may inadvertently penalize patients who, with continued support and time, could eventually achieve significant and sustained benefits from CPAP.

This study directly addresses this concern by examining what happens to patients who do not meet the 90-day threshold in a system that continues to provide support and coverage. The findings offer compelling evidence that the CMS policy may be too prescriptive and may not accurately reflect the reality of long-term CPAP use for a substantial number of patients.

Study Design and Patient Demographics

The research team employed a retrospective observational cohort study design, a common methodology for analyzing real-world patient data over time. The study population comprised adults diagnosed with OSA who were dispensed CPAP devices between January 1, 2020, and December 31, 2023. The selection criterion was at least one recorded CPAP-use episode within the first year of treatment initiation. This broad inclusion ensured a comprehensive overview of patient behavior.

The average age of the study participants was 55.0 years, with a notable gender distribution, as 65.5% of the cohort were men. This aligns with general epidemiological data for OSA, which tends to be more prevalent in males. The severity of OSA was quantified using the apnea-hypopnea index (AHI), calculated with a 4% desaturation criterion, which averaged 32.5 events per hour. An AHI of 30 or higher is generally considered severe OSA, indicating a substantial number of breathing interruptions during sleep.

Patients were meticulously stratified into two groups: those who met the CMS 90-day adherence threshold and those who did not. The study then focused on evaluating device usage during the twelfth month of therapy, specifically defined as the period between days 330 and 360 after treatment initiation. This one-year mark was chosen to assess long-term utilization patterns.

Key Findings: Persistence Beyond the Threshold

The study revealed that a substantial 49.0% of the entire cohort successfully met the CMS 90-day adherence requirement. This indicates that nearly half of patients, under the supportive environment of Kaiser Permanente Southern California, were able to achieve the benchmark usage levels early in their treatment.

However, the most impactful findings emerged when examining the group of patients who failed to meet the initial CMS threshold. This subgroup, comprising 67,906 individuals, demonstrated a remarkable persistence with CPAP therapy. Astonishingly, 36.0% of these initially nonadherent patients were still using CPAP during the twelfth month of treatment. This figure directly contradicts the notion that early nonadherence equates to complete treatment abandonment.

Furthermore, for those who continued to use CPAP despite initial adherence challenges, the average nightly usage was significant. These continued users logged an average of 197 minutes per night, which translates to approximately 3 hours and 17 minutes. Crucially, the study found that CPAP was used for at least four hours on an average of 42.9% of nights within this twelfth month. This level of use is often considered sufficient for therapeutic benefit, as many clinical guidelines suggest that four hours of nightly use is a minimum for meaningful symptom improvement and reduction of OSA-related health risks.

Deeper Dive into Nonadherent Users

The analysis delved deeper into the specific usage patterns of patients who initially failed to meet the CMS threshold. Among this group, 20.9% averaged at least two hours of CPAP use per night during month 12. While this might seem modest, it still represents active engagement with the therapy, which can be a stepping stone to increased adherence. More importantly, 13.6% of these initially nonadherent patients averaged at least four hours of CPAP use per night in the twelfth month. This subset clearly demonstrates that even with a challenging start, long-term therapeutic benefit is achievable.

The study also highlighted demographic factors associated with failing to meet the initial CMS adherence requirement. These included younger age, female sex, non-white race or ethnicity, lower socioeconomic status, and less severe OSA. These characteristics suggest that certain patient populations may face unique barriers to CPAP adherence that are not adequately addressed by a one-size-fits-all adherence metric. For instance, younger individuals might be less motivated by long-term health risks compared to older patients, while socioeconomic factors could influence access to support or the ability to manage treatment side effects.

Implications for Policy and Practice

The findings of this study carry significant implications for how CPAP therapy adherence is assessed and how coverage policies are formulated. The rigid 90-day adherence threshold, as currently enforced by CMS, appears to be an overly simplistic measure that may unfairly deny coverage to patients who could still benefit from CPAP. The study’s results strongly suggest that:

  • Challenging the Assumption: The assumption that poor early adherence predicts long-term treatment abandonment is not universally true. A substantial number of patients who struggle initially can and do continue to use CPAP effectively.
  • Patient-Centered Outcomes: Success in CPAP therapy should be evaluated more holistically, considering patient-reported symptom improvement, quality of life, and objective measures of sleep quality, rather than solely relying on a fixed usage duration within a specific timeframe.
  • Rethinking Coverage Policies: Policymakers and healthcare providers should consider more flexible approaches to CPAP coverage that allow for individual patient circumstances and a longer ramp-up period for therapy initiation. This could involve individualized care plans, enhanced patient education, and more accessible support systems.
  • Understanding Barriers: Further research is needed to understand the specific barriers faced by demographic groups identified as more likely to be nonadherent and to develop targeted interventions.

Limitations and Future Directions

While the study offers valuable insights, it is important to acknowledge its limitations. The research was conducted within an integrated healthcare system that continued coverage regardless of early adherence. This unique environment may not be directly generalizable to healthcare settings where therapy is withdrawn after early nonadherence. In such scenarios, patients might be more motivated to meet the threshold due to the risk of losing access to treatment.

Furthermore, the study reported device-use data rather than direct measures of symptom improvement or clinical outcomes. While CPAP use is a strong proxy for potential benefit, direct correlation with reduced daytime sleepiness, improved cognitive function, or decreased cardiovascular events would further strengthen the argument for flexible adherence policies.

The authors themselves acknowledge that this conference abstract reports device-use data, and future research should focus on clinical outcomes. The findings also highlight the need for more research into the specific reasons for initial nonadherence and the effectiveness of different support strategies in helping patients overcome these challenges. Understanding the long-term health benefits experienced by those who continue CPAP use despite initial adherence issues will be crucial in refining clinical practice and policy.

The study’s citation is: Billings M, et al. Reevaluating the Centers for Medicare and Medicaid Services 90-day CPAP adherence requirement: persistent use among early nonadherent patients. Am J Respir Crit Care Med. 2026;212. https://doi.org/10.1093/ajrccm/aamag162.6465. This work represents a critical step in advocating for a more compassionate and evidence-based approach to CPAP therapy management, ultimately aiming to improve the lives of millions suffering from obstructive sleep apnea.