"Sleep deprivation  typically administered in controlled inpatient settings  rapidly reduces symptoms of depression in roughly half of depression patients according the first metaanalysis on the subject in nearly  years from researchers at the Perelman School of Medicine at the University of Pennsylvania. Partial sleep deprivation sleep for three to four hours followed by forced wakefulness for  hours was equally as effective as total sleep deprivation being deprived of sleep for  hours and medication did not appear to significantly influence these results. The results are published today in the Journal of Clinical Psychiatry.    Although total sleep deprivation or partial sleep deprivation can produce clinical improvement in depression symptoms within  hours antidepressants are the most common treatment for depression. Such drugs typically take weeks or longer to experience results yet . percent of  million U.S. adults filled one or more prescriptions for psychiatric drugs in . The findings of this metaanalysis hope to provide relief for the estimated . million adults who experienced a major depressive episode in .    Previous studies have shown rapid antidepressant effects from sleep deprivation for roughly  percent of individuals yet this response rate has not been analyzed to obtain a more precise percentage since  despite more than  studies since then on the subject.    More than  years since the discovery of the antidepressant effects of sleep deprivation we still do not have an effective grasp on precisely how effective the treatment is and how to achieve the best clinical results said study senior author Philip Gehrman PhD an associate professor of Psychiatry and member of the Penn Sleep Center who also treats patients at the Cpl. Michael J. Crescenz VA Medical Center. Our analysis precisely reports how effective sleep deprivation is and in which populations it should be administered.    Reviewing more than  studies the team pulled data from a final group of  studies executed over a  year period to determine how response may be affected by the type and timing of sleep deprivation performed total vs early or late partial sleep deprivation the clinical sample having depressive or manic episodes or a combination of both medication status and age and gender of the sample. They also explored how response to sleep deprivation may differ across studies according to how response is defined in each study.    These studies in our analysis show that sleep deprivation is effective for many populations said lead author Elaine Boland PhD a clinical associate and research psychologist at the Cpl. Michael J. Crescenz VA Medical Center. Regardless of how the response was quantified how the sleep deprivation was delivered or the type of depression the subject was experiencing we found a nearly equivalent response rate.    The authors note that further research is needed to identify precisely how sleep deprivation causes rapid and significant reductions in depression severity. Also future studies are needed to include a more comprehensive assessment of potential predictors of treatment outcome to identify those patients most likely to benefit from sleep deprivation.        This research was funded by National Institutes of Health grants R HL P NS RMH RMH P EB R MH National Aeronautics and Space Administration grants NNXAKA NBPF NNXAYG NBPF NBPF NNXAMG NXAIG National Heart Lung and Brain Institute U HL National Institute on Drug Abuse  R DAA the Office of Naval Research N the National Aeronautics and Space Administration NNXANG National Space Biomedical Research Institute through NASA NCC  and grant support from Merck and Philips HealthcareRespironics.    In addition to Gehrman and Boland additional authors include Rachel V. Smith from the Cpl. Michael J. Crescenz VA Medical Center and Hengyi Rao David F. Dinges Namni Goel John A. Detre Mathias Basner Yvette I. Sheline and Michael E. Thase all from Penn.    Penn Medicine is one of the worlds leading academic medical centers dedicated to the related missions of medical education biomedical research and excellence in patient care. Penn Medicine consists of the Raymond and Ruth Perelman School of Medicine at the University of Pennsylvaniafounded in  as the nations first medical school and the University of Pennsylvania Health System which together form a . billion enterprise.    The Perelman School of Medicine has been ranked among the top five medical schools in the United States for the past  years according to U.S. News  World Reports survey of researchoriented medical schools. The School is consistently among the nations top recipients of funding from the National Institutes of Health with  million awarded in the  fiscal year.    The University of Pennsylvania Health Systems patient care facilities include The Hospital of the University of Pennsylvania and Penn Presbyterian Medical Center  which are recognized as one of the nations top Honor Roll hospitals by U.S. News  World Report  Chester County Hospital Lancaster General Health Penn Wissahickon Hospice and Pennsylvania Hospital  the nations first hospital founded in . Additional affiliated inpatient care facilities and services throughout the Philadelphia region include Chestnut Hill Hospital and Good Shepherd Penn Partners a partnership between Good Shepherd Rehabilitation Network and Penn Medicine.    Penn Medicine is committed to improving lives and health through a variety of communitybased programs and activities. In fiscal year  Penn Medicine provided . million to benefit our community."