Impact of insomnia on sleep quality and structure in hypertensive patients

Abstract

Background It has been postulated that essential hypertensive (EHT) patients with insomnia may be characterized by disturbed sleep structure. The aim of the study was to compare polysomnographic features in EHT patients with and without insomnia, normotensive insomniacs and healthy volunteers.

Material and methods 67 subjects (mean age: 39.8 ± 12.2 years; 54 M, 13 F) participated in the study. Patients were divided into 4 groups: patients with EHT and insomnia, patients with EHT without insomnia, patients with insomnia without EHT and subjects without EHT and insomnia. Antihypertensive treatment was discontinued 4 weeks prior to study in the group II. All subjects participated in two-days evaluation that included ambulatory blood pressure measurement and polysomnography (PSG).

Results There were no differences in blood pressure levels in all analyzed time periods between patients with hypertension with and without insomnia and between subjects without hypertension with and without insomnia. There were no differences in the frequency of non-dipping patterns between the groups. Patients with hypertension coexisting with insomnia as compared with insomniacs without hypertension and subjects without insomnia with and without hypertension were characterized by most pronounced sleep structure changes: the lowest sleep efficiency index, the longest stage 1 sleep time and by the longest wake after sleep onset time. In the analysis of pooled all subjects data correlations between nocturnal dip and sleep latency time and stage 3 sleep time were found. There were also correlations between nocturnal blood pressure levels and wake time after final awakening and time and latency of deep sleep.

Conclusions Sleep shortening and fragmentation as well as shorter slow wave sleep might be related to the lack of nocturnal dip. The most pronounced sleep structure changes were observed in patients with hypertension coexisting with insomnia.