Sleep apnea testing and outcomes in a large cohort of Medicare beneficiaries with newly diagnosed heart failure.

RATIONALE: Previous studies have demonstrated a high prevalence of sleep apnea (SA) in patients with chronic heart failure (HF), which is associated with higher rates of morbidity, mortality, and health care use.

OBJECTIVES: To investigate the reported incidence, treatment, outcomes, and economic cost of SA in new-onset HF in a large U.S. database.

METHODS: This retrospective cohort study used the 2003 to 2005 Medicare Standard Analytical Files and included subjects with newly diagnosed HF from the first quarter of 2004, without prior diagnosis of SA, stratified by testing, diagnosis, and treatment status.

MEASUREMENTS AND MAIN RESULTS: Among a study population of 30,719 incident subjects with HF, only 1,263 (4%) were clinically suspected to have SA. Of these, 553 (2% of the total cohort) received SA testing, and 545 received treatment. After adjustment for age, sex, and comorbidities, subjects with HF who were tested, diagnosed, and treated for SA had a better 2-year survival rate compared with subjects with HF who were not tested (hazard ratio, 0.33 [95% confidence interval, 0.21-0.51], P < 0.0001). Similarly, among subjects who were tested and diagnosed, those who were treated had a better 2-year survival rate than those who were not treated (hazard ratio, 0.49 [95% confidence interval, 0.29-0.84], P = 0.009).

CONCLUSIONS: In Medicare beneficiaries with HF, comorbid SA is most often not tested and consequently subjects are underdiagnosed and not treated. Meanwhile, in the few subjects in whom a diagnosis of SA is established and treatment is executed, survival improves significantly. These results support the importance of SA testing and treatment for patients newly diagnosed with HF.