Table 1.

Demographic and Sleep Quality Data of Patients with pID and Healthy Controls

	pID Patients	Healthy Controls	p-value
Sociodemographics:
Age (years)	58.1 (12.2)	55.3 (10.0)	p = 0.19
Gender (n. male/ female)	19 / 3	16 / 6	p = 0.13
Education (n. low/medium/high)	3 / 12 / 7	1 / 15 / 6	p = 0.25
Estimated intelligence quotient (MWTB)	112.6 (12.7)	118.4 (14.2)	p = 0.08
Self-assessment of anxiety and depression:
HADS Anxiety (max. 21 points)	8.9 (5.1)	3.7 (2.5)	p = <0.01*
HADS Depression (max. 21 points)	7.5 (4.5)	3.3 (2.6)	p = <0.01*
Subjective sleep quality:
PSQI (max. 21 points)	14.3 (3.2)	4.8 (2.8)	p = <0.01*
ISI (max. 28 points)	18.5 (4.8)	4.0 (4.1)	p = <0.01*
Objective polysomnographic sleep quality:
Sleep Efficiency (%)	58.9 (17.8); CI: 50.97, 66.73
Sleep-onset latency (minutes)	52.2 [86.3]; CI:41.57, 96.11
Wake after sleep onset (minutes)	132.4 (52.0); CI:109.33, 155.41
Sleep-stage transition index (/hour)	14.5 [6.6]; CI: 13.8, 20.22
Arousal index (/hour)	18.9 [14.9]; CI: 15.5, 25.13
Apnea/Hypopnea index (/hour)	2.4 [4.3]; CI: 1.17, 8.29
Periodic Limb Movement index (/hour)	2.4 [6.1] CI: 2.21, 7.23
Sleep stage distribution (% of Time In Bed):
Time Awake	41.2 (17.8); CI:33.24, 49.06
Light sleep	34.2 (14.6); CI:27.76, 40.64
Deep sleep	13.9 (7.4); CI:10.60, 17.18
REM sleep	10.4 (5.6); CI:7.98, 12.90

Notes: Mean and standard deviation (in parentheses) given for normally distributed data. Medians and interquartile ranges (in square brackets) and are presented for non-normally distributed data. CI: 95% Confidence Intervals are given for polysomnographic data. Gender and education expressed as number of participants. An asterisk marks significant differences.

Abbreviations: n., number of; pID, persistent Insomnia Disorder; MWTB, Mehrfachwahl Wortschatz Intelligenz Test B; PSQ, Pittsburgh Sleep Quality Index; ISI, Insomnia Severity Index; HADS, Hospital Anxiety and Depression Scale; REM, Rapid Eye Movement.