Failure of Quality-of-Life Measures to Discriminate between Primary Snorers and Patients with Obstructive Sleep Apnea

Abstract

Objectives:

Investigate differences in quality of life (QoL) between primary snorers and obstructive sleep apnea (OSA) patients using 2 measures: Short-Form 36 (SF-36) and Functional Outcomes of Sleep Questionnaire (FOSQ).

Methods:

This cross-sectional study involved 69 patients who were investigated for snoring between February - December 2011. Each patient completed a SF-36 and FOSQ prior to polysomnogram. Based on polysomnogram outcomes, 4 patient groups were derived: normal, mild, moderate, and severe OSA. Variables analyzed were body-mass-index (BMI), Epworth- sleepiness-score (ESS), SF-36, and FOSQ scores.

Results:

Fourteen patients were normal (mean AHI 2), 14 mild OSA (mean AHI 7.7), 9 moderate OSA (mean AHI 21.9), and 32 severe OSA (mean AHI 57.5). BMI and ESS indices increased progressively from normal to severe OSA. We found no difference in SF-36’s Physical Health component among normal, mild, and moderate OSA, and though it was lowered in severe OSA this was not statistically significant (p = 0.273). Mental health component scores were similar across all groups. OSA patients scored higher across all 5 FOSQ domains compared with simple snorers, but none were statistically significant. However, primary snorers had a significantly higher (p= 0.013) self-reported health state (67.3% +/-16.85) than OSA patients (54.08% +/-17.45 ).

Conclusions:

The broad-based SF-36 fails to distinguish differences in QoL between normal and OSA patients. FOSQ’s psychometric properties have been reported to better reflect functional impairment caused by OSA. However, in our series, FOSQ has not been statistically significant in differentiating between patients with and without OSA.