Better positive airway pressure (PAP) adherence among those with obstructive sleep apnea (OSA), regardless of OSA severity, is associated with significantly lower health care costs over 3 years, according to study findings published in Chest.
Investigators sought to determine the association between PAP adherence and health care costs over a 3-year period among individuals with OSA. The primary endpoints were total health care costs and non-sleep-related health care costs (ie, the cost after sleep-related office visits and sleep-related durable medical equipment costs were subtracted from total health care costs).
The investigation involved participants in the Tele-OSA (ClinicalTrials.gov Identifier: NCT02279901) randomized clinical trial who were prescribed PAP for OSA. The current investigation was based on data collected for 3 months during the trial as well as for 33 months after the trial. Participants in Tele-OSA were recruited from the Kaiser Permanente San Bernardino County Sleep Center in Fontana, California, from 2015 to 2016. All participants had suspected OSA, were deemed appropriate for home sleep apnea testing, and had not previously used PAP therapy.
The current study involved 543 of the 1455 Tele-OSA enrollees. All had been prescribed PAP. Tele-OSA participants without at least 6 months of continuous health plan coverage were excluded. Participants had a mean (SD) age of 50.0 (12.1) years, were 41% women, had an apnea hypopnea index (API) of at least 5 events/hour, and were, on average, obese (mean body mass index, 35.3 [7.5kg/M2]).
Participants were stratified by their PAP adherence/usage patterns during the 3-year follow up period into the following 3 groups: high adherence (consistently ≥4 hours/night); moderate adherence (2-3.9 hours/night or inconsistently ≥4 hours/night); and low adherence (<2 hours/night). Multivariable generalized linear models were used to analyze electronic health records to assess average health care costs (in 2020 US dollars) in 6-month intervals.
There were significantly more White participants in the high adherence group (57%) vs moderate adherence group (39%) vs low adherence group (36%) (P =.01). All groups had moderate/severe disease on average, but API scores were higher for the high adherence (36.7) vs moderate adherence (36.6) vs low adherence (27.7) group (P <.001).
Among the 543 participants, 25% were categorized as high adherence (mean nightly PAP usage, 6.5 [1.0] hours); 22% were moderate adherence (mean nightly PAP usage, 3.7 [1.2] hours); and 52% were low adherence (mean nightly PAP usage, 0.5 [0.5] hours). The high adherence group had the lowest average covariate-adjusted 6-month health care costs (high adherence, $3207 [$251], vs moderate adherence, $3638 [$363], vs low adherence, $4040 [$304]).
Cost differences were significant between the high and low adherence groups ($832; 95% CI, 127-1538; P =.02), nonsignificant between the moderate and low adherence groups ($401; 95% CI, -441 to 1243; P =.36), and nonsignificant between the high and moderate adherence groups ($431; 95% CI, -363 to 1225; P =.27). Among the moderate and low adherence groups, average use was at its highest initially and decreased over time. In contrast, participants in the high adherence group started with high use and usage significantly increased over time.
Investigators noted cost savings appeared to be driven by reduced costs related to hospitalizations. Notably, the association between PAP use and reduced health care costs was significant even among participants with mild OSA.
Study limitations include unmeasured confounders resulting in healthy adherer bias, limited generalizability, misclassification bias concerning comorbidities, and the use of nationally representative costs rather than paid claims for calculation of health care costs.
The researchers concluded that “Better PAP adherence (consistent PAP use of ≥4 hours/night) was associated with significantly lower health care costs over three years in participants with OSA.” They found PAP adherence was inversely associated with 3-year health care cost; with the low adherence group showing the highest average health care cost and high adherence group showing the lowest. “Our study adds to the body of evidence that long-term adherence to PAP therapy can beneficially impact health care costs,” the study authors noted.
An J, Glick HA, Sawyer AM, et al. Association between positive airway pressure adherence and health care costs among individuals with obstructive sleep apnea. Chest. Published online January 24, 2023. doi:10.1016/j.chest.2023.01.025