Long hospital stay, high costs more likely in patients with sleep-disordered breathing

Key takeaways:

• Patients with sleep-disordered breathing had a high likelihood for longer hospital stays and high costs but a low likelihood for death.
• The odds for death rose among those with obesity hypoventilation syndrome.

Patients with obstructive sleep apnea and obesity hypoventilation syndrome each had elevated odds for extended nonsurgical hospital stays and high costs, according to results published in Annals of the American Thoracic Society.

Further, OSA was linked to reduced mortality, whereas obesity hypoventilation syndrome raised the odds for death, according to researchers.

“Investigation is warranted on whether paradoxically higher costs but lower mortality in OSA may be indicative of less vigilance in hospitalized patients with undiagnosed [sleep-disordered breathing],” Anna H. May, MD, MS, staff physician at Louis Stokes Cleveland Veterans Affairs Medical Center and clinical instructor at Case Western Reserve University School of Medicine, wrote.

Using data from the 2017 National Inpatient Sample of the Healthcare Costs and Utilization Project, May assessed 6,046,544 nonsurgical adult hospitalizations to find out how sleep-disordered breathing impacts length of stay, hospitalization costs and mortality in a retrospective cohort analysis.

Of the patients hospitalized, 525,524 (mean age, 63.6 years; 55.8% men; 75.7% white) had sleep-disordered breathing, whereas the remaining 5,521,020 patients (mean age, 57.4 years; 40.9% men: 66.5% white) did not have this condition.

The proportion of patients who died while hospitalized was comparable between those with and those without sleep-disordered breathing (1.9% vs. 2.3%), but more patients with the condition had acute respiratory failure (19.4% vs. 9.2%), asthma (29.4% vs. 14.5%), COPD (31.8% vs. 14.5%) and heart failure (34.8% vs. 15.2%).

OSA was more common than obesity hypoxemia syndrome (94.7% vs. 6.7%) among those with sleep-disordered breathing. Of those with obesity hypoxemia syndrome, 24% simultaneously had OSA.

In logistic regression analysis adjusted for several covariates (age, sex, Elixhauser Comorbidity Index, socioeconomic status, hospital type and insurance type), researchers found that patients with vs. without sleep-disordered breathing had higher odds for longer hospital stays (aOR = 1.17; 95% CI, 1.16-1.17) and greater hospitalization costs (aOR = 1.67; 95% CI, 1.66-1.67).

In contrast, the likelihood for mortality was reduced among those with sleep-disordered breathing compared with those without this condition (aOR = 0.79; 95% CI, 0.77-0.81).

“Lower mortality odds in [sleep-disordered breathing] were not explained by obesity based on stratified analyses,” May wrote.

Researchers further divided patients based on sleep-disordered breathing subtype and found similar results from the main analysis among those with OSA, including higher odds for extended hospital stays and more costs and lower odds for death.

Elevated likelihoods for longer hospital stays and increased costs were also observed in the group of patients with obesity hypoventilation syndrome (length of stay, aOR = 3.05; 95% CI, 2.98-3.13; costs, aOR = 2.67; 95% CI, 2.6-2.73). Notably, these patients faced heightened odds for mortality (aOR = 1.76; 95% CI, 1.66-1.86).

In a subset analysis of only patients hospitalized with acute respiratory failure, researchers found decreased odds for mortality among those with obesity hypoventilation syndrome (aOR = 0.44; 95% CI, 0.41-0.46), as well as those with sleep-disordered breathing and OSA (both aOR = 0.49; 95% CI, 0.47-0.5). All three groups had increased adjusted odds for length of stay and costs.

“The next logical step is to further investigate the heterogeneity of effects and validate these findings in other hospitalization samples,” May wrote. “In particular, the question of what features of the presentation or care path account for increased [length of stay], costs, and especially mortality in [obesity hypoventilation syndrome] is particularly relevant to health promotion and clinical care.”