Relationship between the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale in a sleep laboratory referral population

Department of Community Health and Epidemiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Nature and Science of Sleep 02/2013; 5:15-21. DOI: 10.2147/NSS.S40608
Source: PubMed


Sleep health questionnaires are often employed as a first assessment step for sleep pathology. The Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI) are two commonly employed questionnaire instruments. Aspects of sleep health may be measured differently depending on choice of instrument.
In a patient population at high risk for sleep disorders, referred for polysomnography (PSG), we evaluated the level of association between results from these two instruments. Questionnaire results were also compared with measured PSG parameters.
Records of patients undergoing overnight PSG in the sleep laboratory between February-June 2011 were retrospectively reviewed for eligibility. Inclusion criteria were met by 236 patients. PSQI and ESS scores, demographic information, and PSG data were extracted from each record for analysis. Four subgroups based on normal/abnormal values for ESS and PSQI were evaluated for between-group differences.
Of 236 adult participants, 72.5% were male, the mean age was 52.9 years (13.9), mean body mass index (BMI) 34.4 kg/m(2) (8.3), mean ESS 9.0 (4.8; range: 0-22), PSQI mean 8.6 (4.2; range: 2-19). The Pearson correlation coefficient was r = 0.13 (P = 0.05) for association between ESS and PSQI. Participants with an abnormal ESS were more likely to have an abnormal PSQI score (odds ratio 1.9 [1.1-3.6]; P = 0.03). Those with an abnormal ESS had higher BMI (P = 0.008) and higher apnea-hypopnea indexes (AHI) (P = 0.05). Differences between the four subgroups were observed for BMI and sex proportions, but not for AHI.
We observed limited association between these two commonly used questionnaire instruments, the ESS and the PSQI. These two questionnaires appear to evaluate different aspects of sleep. In terms of clinical application, for global assessment of patients with sleep problems, care should be taken to include instruments measuring different facets of sleep health.

Download full-text


Available from: Prosanta Mondal, Nov 10, 2014
34 Reads
  • Source
    Sleep Medicine 09/2011; 12:S21. DOI:10.1016/S1389-9457(11)70074-0 · 3.15 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Objectives. Methadone maintenance treatment (MMT) patients may achieve up to a 2-week privilege of methadone take-home doses (THD), which is associated with considerable responsibility. MMT patients are characterized as having poor sleep quality and low cognitive states. We studied sleep indices and cognitive status with respect to THD privileges. Methods. A sample of 123 MMT patients stratified by THD groups was studied. Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and the cognitive Clock Drawing Test (CDT) were performed. Results. Thirty-one of 123 patients never had any THD and 92 did (25 had the maximum of 2 weeks). The never THD had history of longer duration of opiate usage and a shorter period in MMT. They had the highest rates of poor sleep (80.6%, PSQI > 5), daily sleepiness ("fall asleep while talking") (41.9%), and impaired cognitive status (58.1%, CDT < 3), while those who had 2-week privileges had the lowest (56, 8, and 28%, respectively). Logistic regression characterized THD patients as no-benzodiazepine and no-cocaine, short opiate usage duration, low ADHD scores, and no cognitive impairment (CDT = 3) and its interaction with treatment duration. Conclusion. Privileges that reflect patients' abstinence and rehabilitation were also expanded to be associated with better cognitive states. These finding confirm the THD dispensing performance. Including CDT as part of the decision for dispensing THD may be considered.
    The World Journal of Biological Psychiatry 03/2014; 15(8). DOI:10.3109/15622975.2014.897003 · 4.18 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Obstructive sleep apnea (OSA) is a common diagnosis in clinical practice. Excessive daytime sleepiness may be a warning for possible OSA. Objectives: To assess the prevalence of excessive daytime sleepiness as measured by the Epworth Sleepiness Scale (ESS) in a rural community population; potential risk factors for OSA were also assessed. Methods: In 2010, a baseline respiratory health questionnaire within the Saskatchewan Rural Health Study was mailed to 11,982 households in Saskatchewan. A total of 7597 adults within the 4624 (42%) respondent households completed the ESS questionnaire. Participants were categorized according to normal or high (>10) ESS scores. Data obtained included respiratory symptoms, doctor-diagnosed sleep apnea, snoring, hypertension, smoking and demographics. Body mass index was calculated. Multivariable logistic regression analysis examined associations between high ESS scores and possible risk factors. Generalized estimating equations accounted for the two-tiered sampling procedure of the study design. Results: The mean age of respondents was 55.0 years and 49.2% were male. The prevalence of ESS>10 and 'doctor diagnosed' OSA were 15.9% and 6.0%, respectively. Approximately 23% of respondents reported loud snoring and 30% had a body mass index >30 kg⁄m2. Of those with 'doctor-diagnosed' OSA, 37.7% reported ESS>10 (P<0.0001) and 47.7% reported loud snoring (P<0.0001). Risk of having an ESS>10 score increased with age, male sex, obesity, lower socioeconomic status, marriage, loud snoring and doctor-diagnosed sinus trouble. Conclusions: High levels of excessive daytime sleepiness in this particular rural population are common and men >55 years of age are at highest risk. Examination of reasons for residual sleepiness and snoring in persons with and without sleep apnea is warranted.
    Canadian respiratory journal: journal of the Canadian Thoracic Society 05/2014; 21(4). · 1.66 Impact Factor
Show more