Clinical application of headache impact test (HIT)-6 and epworth sleepiness scale (ESS) for sleep apnea headache

Abstract

Abstract Background Sleep apnea headache is a major symptom accompanying obstructive sleep apnea (OSA), but relatively little evidence has been reported on the magnitude of its negative effects on patients or the evaluation of therapeutic effects. We quantitatively assessed sleep apnea headache using the Epworth sleepiness scale (ESS) and headache impact test (HIT)-6. Methods The first part of this study enrolled 86 patients (72 male; mean [± standard deviation] age 53.2 ± 13.8 years) who had been diagnosed with OSA by polysomnography in our sleep center and investigated the prevalence and characteristics of sleep apnea headache. The second part enrolled 21 patients (12 male; mean age, 47.5 ± 13.0 years) diagnosed with sleep apnea headache by polysomnography and/or peripheral arterial tonometry and evaluated the effects of OSA therapy on headache. Medical records including ESS, HIT-6, and polysomnographic data were retrospectively analyzed. Results The prevalence of sleep apnea headache among OSA patients was 22.1%, and was higher in female (50.0%) than in male (16.7%). The proportion of N3 and HIT-6 score showed a significant negative correlation (Pearson’s R = -0.51, p < 0.05). In female, median apnea–hypopnea index (AHI) was significantly lower in patients with headache (26.1 /h [interquartile range 21.4–29.6 /h]) than in patients without (54.2 /h [41.3–73.9 /h], p < 0.05, Wilcoxon rank-sum test). HIT-6 and ESS scores improved from 56.4 ± 9.7 to 45.9 ± 8.4 and from 9.0 ± 4.4 to 5.3 ± 4.2 in patients with oral appliance (OA), and from 54.3 ± 10.7 to 44.6 ± 6.1 and from 10.0 ± 4.0 to 4.9 ± 2.9 with continuous positive airway pressure (CPAP). In patients with good CPAP adherence, these scores improved from 58.1 ± 10.8 to 44.0 ± 6.0 and from 9.6 ± 3.8 to 3.6 ± 1.7. Conclusion Among patients with OSA, prevalence of sleep apnea headache was higher in female than in male. In female, headache was associated with relatively mild OSA. OA showed substantial effects on headache in mild to moderate OSA patients. CPAP adherence was important for improving the headache. HIT-6 score appears useful for the diagnosis and management of sleep apnea headache.