Determinants of self-reported sleep quality in healthy sleepers and patients

Abstract

A clear clarification of which objective variables are predictive of the subjective sleep experience, and furthermore, which variables of the subjective sleep variables are an adequate representation of the sleep quality score are missing. This may lead to people not identifying possible sleep problems or to people who feel misunderstood when the problem is not objectively observed. Data from the SIESTA database were used, which consists of two consecutive nights of polysomnography and includes subjective data of 156 healthy persons and 95 patients (age range 20–95). Among other things, the strongest significant correlations were found when the difference between nights was taken, for instance, between the subscore “Sleep Quality” of the Subjective sleep and awakening questionnaire (SSA-1) and total sleep time (r = .423, p < .001). For the mental disorder group, stronger correlations were observed between the absolute sleep measurements of night 1 and SSA-1 (wake time after sleep onset: r = .732, p < .001). The subscore “Sleep Quality” was sufficient as a representative for the subjective sleep quality score. Our findings indicate that intra-individual variability plays a role and to enhance the insight more nights are needed when investigating the association between subjective sleep quality and objective sleep measurements.

Keywords:

• sleep measurements
• subjective sleep quality
• sleep variability

PUBLIC INTEREST STATEMENT

The importance of a good night’s sleep is increasingly known to the general public. More and more people want to monitor their sleep to find out how they have slept, especially people who are worried about their sleep. Until now, low to medium correlations were found between objective sleep measures and subjective sleep quality. This may lead on the one hand to people not identifying a possible sleep problem subjectively, in the case of an absence of an objective sleep measurement. On the other hand, this may lead to people who subjectively report having a sleep problem becoming frustrated and distressed as their problem is not objectively observed. A reason for the low correlation could be on how the association has been analyzed so far. This article studies with an explorative analysis aforementioned relationship from a different angle. Differences between nights was a great predictor for the subjective sleep quality, meaning that more research studies are needed that investigate aforementioned relationship in a longitudinal way.

Competing interests

The authors declare no competing interests.

Cover Image

Source: Cover doctoral thesis M. Goelema

Additional information

Funding

The authors received no direct funding for this research.

Notes on contributors

Maaike Goelema

Maaike Goelema started her professional career as a PhD student at the Eindhoven University of Technology. The PhD project was performed at the User Centered Engineering research group of the faculty of Industrial design in collaboration with Philips Research. The topic of her PhD project was “Perceived sleep quality in a personal health monitoring context.” Maaike obtained her PhD under the supervision of Professor Panos Markopoulos and Reinder Haakma in 2018. Tim Leufkens is a sleep researcher within Royal Philips. Maaike is currently employed at a mental healthcare company treating patients with various mental illnesses.