Obstructive sleep apnea
Prevalence of obstructive sleep apnea–hypopnea in severe versus moderate asthma

https://doi.org/10.1016/j.jaci.2009.05.016Get rights and content

Background

Previous studies have suggested a link between obstructive sleep apnea and poor asthma control, which may be mediated through airway inflammation, obesity, and other mechanisms.

Objective

To test the hypothesis that the prevalence and severity of sleep apnea is greater among patients with severe compared with moderate asthma and controls without asthma.

Methods

Complete overnight home polysomnography was performed in 26 patients with severe asthma consecutively recruited to a difficult asthma program, 26 patients with moderate asthma, and 26 controls without asthma of similar age and body mass index. Flow rates and Juniper asthma control and quality of life questionnaires were also obtained.

Results

Obstructive sleep apnea–hypopnea, defined by an Apnea–Hypopnea Index ≥15 events/h of sleep scored using Chicago criteria, was present in 23 of 26 (88%) patients with severe asthma, 15 of 26 (58%) patients with moderate asthma, and 8 of 26 (31%) controls without asthma (χ2: P < .001). Using the more restrictive scoring criteria applied in the Wisconsin cohort study, Apnea-Hypopnea Index ≥5/h was present in 50% (severe), 23% (moderate), and 12% (control) of subjects (P = .007). Mean nocturnal arterial oxygen saturation was significantly lower in patients with severe asthma versus controls, and apnea-hypopnea severity measures were significantly worse for both asthmatic groups compared with controls. Among subjects with asthma, no significant correlations were identified between the severity of sleep-disordered breathing and asthma severity or control measures (FEV1, Juniper scores).

Conclusions

Obstructive sleep apnea–hypopnea was significantly more prevalent among patients with severe compared with moderate asthma, and more prevalent for both asthma groups than controls without asthma. These observations suggest potential pathophysiologic interactions between obstructive sleep apnea–hypopnea and asthma severity and control.

Section snippets

Subjects

Subjects with asthma were recruited from our Difficult Asthma Program.2 Recruitment to the program was solely on the basis of asthma history. Severe asthma was defined according to American Thoracic Society criteria1 and required at least 1 major criterion: daily oral steroids for >50% of the previous 12 months, or high-dose inhaled steroid: fluticasone ≥1000 μg/d or equivalent, and at least 1 other add-on therapy continuously for ≥12 months; and ≥2 minor criteria: daily short-acting β-agonist,

Results

Subject characteristics are shown in Table I. The 3 groups were of similar age, sex distribution, and BMI. Flow rates were significantly lower and Juniper asthma control questionnaire scores significantly higher (poorer control) among the severe versus moderate asthma groups, as anticipated. Asthma quality of life scores were significantly lower (less favorable) for patients with severe asthma than for patients with moderate asthma. Eight patients with severe asthma (31%) and 2 patients with

Discussion

In this study, by using complete overnight polysomnography, we identified a strikingly high prevalence of OSAH among patients with severe asthma compared with age-matched and BMI-matched patients with moderate asthma and control subjects without asthma. OSAH also tended to be more prevalent among patients with moderate asthma than controls without asthma, although this did not achieve statistical significance. Mean nocturnal SaO2 was significantly lower for the severe asthma group compared with

References (37)

  • Proceedings of the ATS workshop on refractory asthma: current understanding, recommendations, and unanswered questions. American Thoracic Society

    Am J Respir Crit Care Med

    (2000)
  • C.S. Chan et al.

    Nocturnal asthma: role of snoring and obstructive sleep apnea

    Am Rev Respir Dis

    (1988)
  • A. ten Brinke et al.

    Risk factors of frequent exacerbations in difficult-to-treat asthma

    Eur Respir J

    (2005)
  • M. Yigla et al.

    Difficult-to-control asthma and obstructive sleep apnea

    J Asthma

    (2003)
  • C. Lafond et al.

    Impact of CPAP on asthmatic patients with obstructive sleep apnoea

    Eur Respir J

    (2007)
  • J.G. Mastronarde et al.

    Sleep quality in asthma: results of a large prospective clinical trial

    J Asthma

    (2008)
  • C. Guilleminault et al.

    Nocturnal asthma: snoring, small pharynx and nasal CPAP

    Eur Respir J

    (1988)
  • E. Juniper et al.

    Development and validation of a questionnaire to measure asthma control

    Eur Respir J

    (1999)
  • Cited by (0)

    Supported by grants from the Richard and Edith Strauss Canada Foundation, McGill University Health Centre Research Institute, and the Fonds de la Recherche en Santé du Québec. J.Y.J. was a recipient of the Ann Woolcock Memorial Fellowship, was supported by GlaxoSmithKline Canada Inc, and is a CHEST Foundation Awardee. R.J.K. was a Clinical Research Scholar of the Fonds de la Recherche en Santé du Québec. Q.H. is a recipient of a Chercheur Nationale award from the Fonds de la Recherche en Santé du Québec.

    Disclosure of potential conflict of interest: P. Ernst is on the advisory board and speakers' bureau for AstraZeneca, GlaxoSmithKline, Merck, Novartis, Nycomed, and Pfizer and receives grant support from the Canadian Institutes of Health Research. R. Olivenstein receives grant support from Novartis and Asthmatx. Catherine Lemière receives grant support from the National Institute for Occupational Safety and Health and the Institut de Recherche Robert-Sauvé en Santé et en Securité du Travail. R. J. Kimoff receives speaker fees from GlaxoSmithKline and VitalAire Inc and receives grant support from the Fonds de la Recherche en Santé du Québec and the Multiple Sclerosis Society of Canada. The rest of the authors have declared that they have no conflict of interest.

    View full text