title: The influence of environmental factors on sleep quality in hospitalized medical patients.
abstract: BACKGROUND
  Sleep-wake disturbances are common in hospitalized patients but few studies have assessed them systematically. The aim of the present study was to assess sleep quality in a group of medical inpatients, in relation to environmental factors, and the switch to daylight-saving time.
  
  
  METHODS
  Between March and April 2013, 118 consecutive inpatients were screened and 99 (76 ± 11 years; hospitalization: 8 ± 7 days) enrolled. They slept in double or quadruple rooms, facing South/South-East, and were qualified as sleeping near/far from the window. They underwent daily sleep assessment by standard questionnaires/diaries. Illuminance was measured by a luxmeter at each patient's eye-level, four times per day. Noise was measured at the same times by a phonometer. Information was recorded on room lighting, position of the rolling shutters and number/type of extra people in the room.
  
  
  RESULTS
  Compliance with sleep-wake assessment was poor, with a range of completion of 2-59%, depending on the questionnaires. Reported sleep quality was sufficient and sleep timing dictated by hospital routine; 33% of the patients reported one/more sleepless nights. Illuminance was generally low, and rolling shutters half-way down for most of the 24 h. Patients who slept near the window were exposed to more light in the morning (i.e., 222 ± 72 vs. 174 ± 85 lux, p < 0.05 before the switch; 198 ± 72 vs. 141 ± 137 lux, p < 0.01 after the switch) and tended to sleep better (7.3 ± 1.8 vs. 5.8 ± 2.4 on a 1-10 scale, before the switch, p < 0.05; 7.7 ± 2.3 vs. 6.6 ± 1.8, n.s. after the switch). Noise levels were higher than recommended for care units but substantially comparable across times/room types. No significant differences were observed in sleep parameters before/after the switch.
  
  
  CONCLUSIONS
  Medical wards appear to be noisy environments, in which limited attention is paid to light/dark hygiene. An association was observed between sleep quality and bed position/light exposure, which is worthy of further study.
authors.affiliation: Department of Medicine, University of Padova , Padova , Italy.
authors.forename: Milena
authors.initials: M
authors.lastname: Bano
authors.affiliation: Department of Medicine, University of Padova , Padova , Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Chiaromanni
authors.affiliation: Department of Medicine, University of Padova , Padova , Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Corrias
authors.affiliation: Department of Medicine, University of Padova , Padova , Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Turco
authors.affiliation: Department of Medicine, University of Padova , Padova , Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: De Rui
authors.affiliation: Department of Medicine, University of Padova , Padova , Italy.
authors.forename: Piero
authors.initials: P
authors.lastname: Amodio
authors.affiliation: Department of Medicine, University of Padova , Padova , Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Merkel
authors.affiliation: Department of Medicine, University of Padova , Padova , Italy.
authors.forename: Angelo
authors.initials: A
authors.lastname: Gatta
authors.affiliation: Department of Biology, University of Padova , Padova , Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Mazzotta
authors.affiliation: Department of Biology, University of Padova , Padova , Italy.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Costa
authors.affiliation: Department of Medicine, University of Padova , Padova , Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Montagnese
keywords: circadian rhythms; hospital; internal medicine; light; noise; sleep