Subjective sleep complaints indicate objective sleep problems in psychosomatic patients: a prospective polysomnographic study

Figures & data

Table 1 Comparison of the polysomnographical results between good and very poor sleepers

Objective parameter	PSQI >10 (mean ± SD)	PSQI <6 (mean ± SD)	Test statistics
			T	P-value
SOL (minutes)	12.75±17.68	9.05±7.36	0.96	0.341
TST (minutes)	396.01±60.27	424.37±45.21	1.86	0.066
WASO (%/TiB)	22.68±10.2	21.61±7.81	0.41	0.680
TWASO (minutes)	46.97±39.15	31.39±22.37	2.2	0.032
SE (%)	86.87±8.81	91.67±4.4	3.64	0.001
Content REM sleep (%)	19.04±6.11	19.08±3.61	0.04	0.972
Content slow wave sleep (%)	14.34±5.11	16.30±4.11	−1.67	0.097
Microarousal(per hour)	31.50±14.85	33.48±18.33	0.54	0.584

Notes: Very poor sleepers: PSQI >10, n=80 patients. Good sleepers: PSQI <6, n=19 patients. Significant results are shown in bold (P<0.05, one tailed).

Abbreviations: PSQI, Pittsburgh Sleep Quality Index; SD, standard deviation; SOL, sleep onset latency; TST, total sleep time; WASO, awake after sleep onset; TWASO, time awake after sleep onset; SE, sleep efficiency; REM, rapid eye movement.

Table 2 Correlation between subjective and objective sleep parameters

Objective parameter	Subjective parameter
	Condition next morning			sRF	sSOL	sESOL	sWASO	sEWASO	sTWASO	sETWASO	sTST	sETST
	Oppressed–unburdened	Weak–bright	Tensed–relaxed
oSOL	−0.085	−0.031	−0.047	0.096	0.336^**	0.173^*	0.160	0.061	0.160	0.065	0.065	0.019
oTST	0.054	0.048	0.047	0.077	0.171	0.026	0.028	0.158	0.028	0.023	0.383^**	0.209^*
oWASO	0.047	0.045	0.124	0.185	0.183	0.066	0.021	0.183	0.021	0.194	0.097	0.042
oTWASO	0.087	0.103	0.185	0.336^**	0.240	0.181	0.317^*	0.023	0.317^*	0.262^*	0.166	0.075
oSE	0.152	0.143	0.176^*	0.239^**	0.361^**	0.246^**	0.074	0.048	0.074	0.223^*	0.262^*	0.047
oMA	0.064	0.010	0.026	0.046	0.019	0.020	0.014	0.195	0.014	0.047	0.035	0.014
oREM	0.082	0.143	0.073	0.049	0.134	0.051	0.056	0.084	0.056	0.005	0.065	0.050
oSWS	0.093	0.000	0.081	0.066	0.164	0.206	0.021	0.074	0.021	0.119	0.047	0.005

Notes: Significant results are highlighted in bold (n=99, ^*P<0.005, ^**P<0.001, two tailed).

Abbreviations: sRF, subjective restfulness; sSOL, subjective sleep onset latency; sESOL, subjective evaluation of SOL; sWASO, subjective awake after sleep onset; sEWASO, subjective evaluation of awake after sleep onset; sTWASO, subjective time awake after sleep onset; sETWASO, subjective evaluation of time awake after sleep onset; sTST, subjective total sleep time; sETST, subjective evaluation of total sleep time; oSOL, objective sleep onset latency; oTST, objective total sleep time; oWASO, objective awake after sleep onset; oTWASO, objective time awake after sleep onset; oSE, objective sleep efficiency; oMA, objective microarousal; oREM, objective rapid eye movement sleep; oSWS, objective slow wave sleep.