Stability of the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Questionnaires over 1 year in early middle-aged adults: The CARDIA Study

Department of Health Studies, University of Chicago, 5841 S. Maryland Ave, MC2007, Chicago, IL 60637, USA.
Sleep (Impact Factor: 4.59). 12/2006; 29(11):1503-6.
Source: PubMed


To describe the stability of the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS) scores over 1 year among a population-based sample of black and white early middle-aged adults.
More than 600 participants, aged 38 to 50 years, from the Chicago site of the Coronary Artery Risk Development in Young Adults (CARDIA) Study.
The PSQI and ESS were completed twice, approximately 1 year apart, between 2003 and 2005. Seven PSQI 4-level component scores, a global PSQI score, and the ESS scores were calculated. A PSQI global score greater than 5 was classified as poor quality sleep, and an ESS score greater than 10 was classified as high daytime sleepiness.
The mean+/-SD PSQI score was 5.7+/-3.1 in Year 1 and 5.9+/-3.1 in Year 2. The mean ESS score was 7.4+/-4.3 in Year 1 and 7.2+/-4.2 in Year 2. The Pearson correlation coefficient for the PSQI score in both years in the full sample was .68 and ranged from .54 among black men to .72 among black women. The Pearson correlation coefficient for the ESS score in both years in the full sample was .76 and ranged from .70 among black men to .80 among white men. In the full sample, 76% had the same PSQI dichotomous classification, and 85% had the same ESS dichotomous classification in both years.
These results suggest that the PSQI and ESS are stable measures of sleep quality and sleepiness over the past year in early middle-aged adults.

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Available from: Kristen L Knutson, Oct 01, 2015
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    • "It is thought that reductions in sleep quality results in longer exposure to elevated sympathetic nervous system activity and to waking physical and psychological stressors [2]. Consequently, there is growing evidence that significant correlations exist between poor sleep quality and the development of comorbid conditions including obesity, hypertension, diabetes mellitus, pain, and even death [2] [3] [4] [5] [6] [7] [8] [9]. "
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    ABSTRACT: Objective. Sleep disturbances are common in patients with carpal tunnel syndrome (CTS). This study investigates the impact of CTS on sleep quality and clarifies the magnitude of this relationship. Methods. This is a prospective investigation of patients with CTS. Patients responded to the Levine-Katz Carpal Tunnel and the Pittsburgh Sleep Quality Index (PSQI) questionnaires to assess symptom severity and quality, respectively. Descriptive and bivariate analyses summarized the findings and assessed the correlations between CTS severity and sleep quality parameters. Results. 66 patients (53F, 13M) were enrolled. Patients reported a sleep latency of 30.0 (±22.5) minutes, with a total sleep time of 5.5 (±1.8) hours nightly. Global PSQI score was 9.0 (±3.8); 80% of patients demonstrated a significant reduction in sleep quality (global PSQI score >5). Increased CTS symptom and functional severity both resulted in a significant reduction in quality and time asleep. Both significantly correlated with subjective sleep latency, sleep disturbance, use of sleep promoting medications, daytime dysfunction, and overall global PSQI score. Conclusions. The findings confirm the correlation of sleep disturbances to CTS, that is, significant reduction of sleep duration and a correlation to sleep quality. Patients sleep 2.5 hours less than recommended and are at risk for comorbid conditions.
    02/2014; 2014:962746. DOI:10.1155/2014/962746
    • "Kingshott et al., 1998 [40] Fair e e e 22. Kingshott, Engleman et al., 1998 [46] e e Good e 23. Knutson et al., 2006 [35] e Poor e e 24. Martin et al., 1997 [84] e e Fair e 25. "
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    • "It includes subscales assessing sleep latency, sleep duration, sleep disturbances, and daytime-dysfunction. Several psychometric aspects of the PSQI have been investigated and reported, such as internal consistency, reliability and construct validity, and stability over 1 year among a population-based sample (Curcio et al., in press; Backhaus et al., 2002; Buysse et al., 1989; Knutson et al., 2006; Carpenter and Andrykowski, 1998). A global score above 5 has been found to be a reliable and validated indicator for clinically relevant pathological sleep (Backhaus et al., 2002; Curcio et al., in press; Aloba et al., 2007). "
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