Disturbed Sleep in Adult Patients with Sickle Cell Disease Assessed by the Pittsburgh Sleep Quality Index.

Abstract

Although life expectancy for patients with sickling hemoglobinopathies has been improving in recent years, these patients continue to suffer significant morbidity throughout their lives, and pain is a prominent feature of these disorders. It has been shown that, in the primary care population, patients with the highest risk for sleep disturbances include those with pain (Alattar M, et al., J Am Board Fam Med , 2007, Vol 20, pp 365–74). It has also been reported that patients with sickle cell diseases have clinical features which resemble fibromyalgia syndrome (Schlessinger N, J Rheum , 2004, Vol 31, pp 598–600); fibromyalgia syndrome is characterized both pain and impaired sleep, among other features. In order to further investigate sleep disorders in sickle cell disease patients, patients in a sickle cell disease clinic were asked to complete the Pittsburgh Sleep Quality Index (PSQI) questionnaire.Methods: Using a form IRB-approved specifically for this study, the PSQI was offered to patients in a sickle cell disease clinic, and completed anonymously.Results: 20 patients completed the PSQI with responses meaningful for analysis; they ranged in age from 21 to 50 years. On average, patients reported very poor overall quality of sleep; the mean Global PSQI score was 11.8 (S.D.4.8); this is as compared to historical, healthy control subjects who had a subjective mean Global PSQI score of 2.6. (Buysse D et al, Psychiatry Research , 1989, Vol 28, pp 193–213). All respondents reported that pain contributed to poor sleep at least once during the month prior to the survey, and half of the patients reported that pain contributed to poor sleep at least three times in the week prior to the survey. Fifty percent of those surveyed reported no sense of nocturnal dyspnea whatsoever; only 3 individuals reported that they felt that dyspnea contributed to poor sleep three or more times in the week prior to the survey, and frequent daytime somnolence was reported by only 10 percent of sickle cell patients responding to the survey. Habitual sleep efficiency appears poor in these patients, and subjective sleep quality is also reported as generally poor.Conclusions: Sleep disturbances appear to be very common in sickle cell disease patients, and some, but not all, aspects of these sleep disturbances resemble the characteristics of sleep impairment seen in patients with fibromyalgia syndrome (Osorio C, et al., J Rheum , 2006, Vol 33, pp 1863–65). Although sleep impairment in patients with sickle cell diseases has been attributed to sleep apnea syndromes in a subset of patients with sickle cell diseases, sleep disturbance associated with pain in sickle cell disease appears to be more widespread than could be explained by sleep apnea syndromes. Sleep disturbances associated with pain in sickle cell diseases may in turn lead to further exacerbation of symptoms arising from poor sleep. Interventions to improve sleep may reduce overall pain in these patients, as appears to be the case for patients with fibromyalgia syndrome (Rooks D, Curr Opin Rheum , 2007, Vol 2, pp 111–17).