Evidence of Possible Irritable Larynx Syndrome in Obstructive Sleep Apnea: An Epidemiologic Approach

Abstract

"Irritable larynx syndrome" (ILS) often refers to a constellation of laryngeal-based symptoms including chronic cough (CC), diurnal dyspnea, and dysphonia. In patients with OSA, we examined: (1) the frequency, severity, comorbidity, risks and triggers of each problem, (2) whether these symptoms were compatible with stereotypic ILS and (3) the role of CPAP in their expression. Cross-sectional, descriptive epidemiology study. Sleep-Wake Center at University of Utah Health Care, Salt Lake City, UT. Ninety-four individuals with OSA (53 men, 41 women; mean age 54.7 ± 12.8 yrs.) underwent an extensive telephone interview that addressed study objectives. Long-term CC, daytime breathing and voice problems were common, especially among women despite less severe OSA. Women, more than men, reported all three chronic conditions alone or in combination: CC (44% vs 11.3%), diurnal dyspnea (41.5% vs 13.2%) and voice disorders (41.5% vs 13.2%). Symptoms were not associated with age, BMI or Apnea Hypopnea Index after adjusting for sex. Although evidence supporting stereotypic ILS symptomatology was inconsistent, those participants with a voice disorder were 3.3 (95% CI=1.8-6.0) times more likely to report CC and 2.4 (95% CI=1.3-4.4) times more likely to experience diurnal dyspnea. Esophageal reflux, post-nasal drip, and frequent sinus infections were significantly associated with all three conditions. Triggers that provoked or made symptoms worse varied by condition and sex. Nightly, humidified CPAP use was associated with fewer symptoms overall and improved quality of life. Symptoms suggestive of possible ILS are common in OSA, especially among women, and lessened by nightly CPAP use.