The Relation Between Daytime Sleepiness and Clinical Outcomes in Patients with Obstructive Sleep Apnea Syndrome (OSAS)

Introduction: Obstructive sleep apnea syndrome (OSAS) is a common disorder which is characterized by the recurrent episodic disruption of normal breathing (apnea, hypopnea) during sleep due to obstruction in upper respiratory tract and it is related with many organ systems. Frequent disruption of sleep activates sympathetic system which causes impairment of sleep and cardiovascular system disorders. The aim of this study is to investigate the effect of daytime sleepiness on clinical outcomes in patients diagnosed with OSAS. Materials and Methods: Study was designed in adult patients who received polysomnography for the first time for diagnosis which was evaluated in Hacettepe Hospital Sleep Laboratory Unit between September 2009 and March 2010. Patients' demographic data was recorded and blood pressure, anthropometric measurements, polysomnography and respiratory function test were evaluated. Moreover; Charlson Comorbidity Index, Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI), SF 36 Quality of Life Scale and Sleep Hygiene Index scores were calculated for each patient. Results: The present study was comprised of 99 patients; 36 females (36.4%) and 63 males (63.6%). Mean body mass index was 32.8 +/- 6.9 kg/m(2), waist circumference was 110.2 +/- 14.1 cm, neck circumference was 41.2 +/- 4 cm, systolic blood pressure was 127.7 +/- 19.3 mmHg, diastolic blood pressure was 84.6 +/- 12.6 mmHg. 'Normal' group was consisted of 25 people whose Apnea-Hypopnea Index (AHI) was <15/h and ESS was <10. 'OSAS/UD' group was consisted of 37 patients whose AHI was <15/h and ESS was <10. 'OSAS/U' group was consisted of 33 patients whose AHI was >5/h and ESS was >= 10. The remaining 4 people were excluded from the statistical analysis whose AHI was <5/h and ESS was >= 10. "Social function" scores of SF 36 Quality of Life Scale were significantly lower in the 'OSAS/U' group than in the 'Normal' group. "Emotional status" scores were lower in the 'OSAS/U' group than in the 'OSAS/UD' group which was also statistically significant. "Subjective sleep quality" scores were component of PSQI which were higher in the 'OSAS/U' group than in the 'Normal' group. Nevertheless "sleep latency" scores were significantly higher in the 'Normal' group than in the other groups. "Daytime dysfunction" scores were significantly higher than in the other groups. There was no statistical difference in "hypertension" and "Charlson Comorbidity Index" scores between the groups. Discussion: Life quality and sleep quality were worse in the patients with OSAS who had complaints of sleepiness. We found no relationship between the complaints of sleepiness and hypertension or comorbidity.