Author Affiliations: Department of Medicine, University of Chicago, Chicago, Illinois (Drs Arora and Knutson). Mr Yoder is a medical student at the Pritzker School of Medicine, University of Chicago.
We certainly agree with our colleagues that studying the effect of noise disruption in the hospital setting on sleep architecture, particularly on the level of slow-wave sleep (SWS) is critical. Because our study used actigraphy and not polysomnography, we are unable to ascertain the association between hospital noise and sleep architecture in our sample. In future studies, quantifying the SWS loss due to hospitalization may help understand adverse health consequences hospitalized patients face. This is especially the case, as our colleagues at the University of Chicago and others have demonstrated that selective deprivation of SWS is associated with a variety of adverse health consequences that could affect the recovery process from acute illness, including impaired blood glucose tolerance, higher blood pressure, and decreased pain tolerance.1- 3 Given the typical compensatory increase of SWS in response to acute sleep deprivation, another interesting question is whether a corresponding “rebound” of SWS occurs in recently hospitalized patients.
While studies examining the relationship between noise and sleep architecture, such as percentage of SWS, in hospitalized ward patients are lacking, it is worth examining the more extensive literature in the intensive care unit (ICU) setting, which could inform hypotheses to test in hospitalized ward patients. For example, studies show that ICU patients experience sleep fragmentation with a predominance of stage 1 sleep and a lack of SWS.4 Moreover, at least 1 study has shown that a simple intervention, ear plugs, for ICU patients can result in a greater amount of rapid eye movement sleep.5 These studies highlight that it is reasonable to suggest that noise in the hospital setting disrupts sleep architecture. Although using polysomnography may present challenges in studying hospitalized ward patients, future work should attempt to ascertain whether hospitalized patients face selective SWS deprivation due to nighttime noise and what the potential impact may be on health and recovery for these patients.
Correspondence: Dr Arora, Department of Medicine, University of Chicago, 5841 S Maryland Ave, Chicago, IL 60637 (email@example.com).
Financial Disclosure: None reported.
Arora VM, Yoder JC, Knutson KL. To Sleep or Not To Sleep: Do We Forget Our Patient's Sleep?—Reply. Arch Intern Med. 2012;172(9):746-747. doi:10.1001/archinternmed.2012.1092