Browsing by Subject "Circadian rhythm"

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  • Tan, Xiao; van Egmond, Lieve; Partinen, Markku; Lange, Tanja; Benedict, Christian (2019)
    Sleep and circadian disruptions are frequently observed in patients across hospital wards. This is alarming, since impaired nocturnal sleep and disruption of a normal circadian rhythm can compromise health and disturb processes involved in recovery from illness (eg, immune functions). With this in mind, the present narrative review discusses how patient characteristics (sleep disorders, anxiety, stress, chronotype, and disease), hospital routines (pain management, timing of medication, nocturnal vital sign monitoring, and physical inactivity), and hospital environment (light and noise) may all contribute to sleep disturbances and circadian misalignment in patients. We also propose hospital-based strategies that may help reduce sleep and circadian disruptions in patients admitted to the hospital. (C) 2018 The Authors. Published by Elsevier B.V.
  • Merikanto, Ilona; Lahti, Jari; Kuula, Liisa; Heinonen, Kati; Räikkönen, Katri; Andersson, Sture; Strandberg, Timo; Pesonen, Anu-Katriina (2018)
    Objective: Recent genome-wide association studies (GWASs) have revealed new genetic variants behind self-reported individual circadian preference, a distinct biological trait that is fairly stable during adulthood. In this study we analyze whether these genetic variants associate with objectively measured sleep timing from childhood to adolescence, over a nine-year period, with self-reported circadian preference during late adolescence. Methods: The participants (N = 100, 61% girls) came from a community cohort from Finland born in 1998. Sleep midpoint was measured with actigraphy at 8, 12 and 17 years. Circadian preference was self-reported at the age of 17 years. Single nucleotide polymorphisms (SNPs) were extracted at 12 years of age from the Illumina OmniExpress Exome 1.2 bead array data. Weighted polygenic risk scores (PRSs) were calculated based on top SNPs from a recent GWAS for morningness-eveningness in an adult population. Results: The PRS for circadian preference towards morningness was associated with earlier sleep midpoint from childhood to adolescence. When the time points were analyzed separately, the association between genetic tendency towards morning preference and earlier sleep midpoint was strongest among the 17-year-olds. Furthermore, the shift towards later sleep rhythm from early to late adolescence was milder for those with a higher PRS for morning preference. PRS for morning preference was also associated with self-reported circadian preference towards morningness in late adolescence. Conclusion: Our results suggest that genetic variants found for circadian preference in adults are already associated with objective sleep timing during childhood and adolescence, and predict individual developmental sleep trajectories from childhood onwards. (C) 2018 Published by Elsevier B.V.
  • Räty, Silja; Martinez-Majander, Nicolas; Suomalainen, Olli; Sibolt, Gerli; Tiainen, Marjaana; Valkonen, Kati; Sairanen, Tiina; Forss, Nina; Curtze, Sami (2021)
    Background: There is contradicting evidence on the outcome of emergency patients treated during weekends versus weekdays. We studied if outcome of ischemic stroke patients receiving intravenous thrombolysis (IVT) differs according to the treatment time. Methods: Our retrospective study included consecutive patients receiving IVT within 4.5 h of stroke onset between June 1995 and December 2018 at the Helsinki University Hospital. The patients were compared based on the treatment initiation either during weekdays (Monday to Friday) or weekend (Saturday and Sunday). The primary outcome was 3-month mortality and secondary outcomes comprised 3-month modified Rankin Scale (mRS) and incidence of symptomatic intracerebral hemorrhage (sICH). Additional analyses studied the effect of IVT treatment according to non-office hours, time of day, and season. Results: Of the 3980 IVT-treated patients, 28.0% received treatment during weekends. Mortality was similar after weekend (10.0%) and weekday (10.6%) admissions in the multivariable regression analysis (OR 0.78; 95% CI 0.59-1.03). Neither 3-month mRS (OR 0.98; 95% CI 0.86-1.12), nor the occurrence of sICH (4.2% vs 4.6%; OR 0.87; 95% CI 0.60-1.26) differed between the groups. No outcome difference was observed between the office vs non-office hours or by the time of day. However, odds for worse outcome were higher during autumn (OR 1.19; 95% CI 1.04-1.35) and winter (OR 1.15; 95% CI 1.01-1.30). Conclusion: We did not discover any weekend effect for IVT-treated stroke patients. This confirms that with standardized procedures, an equal quality of care can be provided to patients requiring urgent treatment irrespective of time.
  • Uhre, Veli-Matti (Helsingin yliopisto, 2020)
    Uni on välttämätöntä ihmisen toiminnalle ja sen puute tai huono laatu altistavat monille sairauksille. Perimällä on suuri vaikutus unensäätelyyn ja univalverytmin preferenssiin eli niin sanottuun kronotyyppiin. Eri arvioiden mukaan perimän osuus yksilön kronotyyppiin on noin 50 prosenttia. Viimeaikaiset koko perimän kattavat assosiaatiotutkimukset (genome wide association study, GWAS) ovat havainneet uusia kronotyyppiin vaikuttavia yhden emäksen muutoksia (single nucleotide polymorphs, SNPs). Tässä tutkimuksessa haluttiin selvittää kronotyypin taustalla vaikuttavaa perinnöllistä taipumusta vastasyntyneillä. Tutkimus on osa laajempaa CHILD-SLEEP kohorttitutkimusta, joka kattaa 1643 vastasyntynyttä sekä heidän vanhempansa. Tutkimuksessa käytettiin vanhempien täyttämien lasten unta ja vuorokausirytmiä selvittävien standardoitujen kyselytutkimusten tuloksia sekä 1345 vastasyntyneen geneettisiä näytteitä. Kyselyt toteutettiin vauvojen ollessa kolmen, kahdeksan ja 24 kuukauden ikäisiä. Aamuvirkkuisuuteen yhdistyvä geneettinen riskipisteytys muodostettiin aikaisemmissa tutkimuksissa havaittujen SNP:ien pohjalta. Yhteensä yhdeksän SNP:iä valikoitui mukaan monigeeniseen riskipisteytykseen. Kyselytutkimusten pohjalta kerättyjä unimuuttujia analysoitiin suhteessa riskipisteytykseen. Analyysissä mukana olleita muuttujia olivat yöunen, päiväunen ja kokonaisunen määrä sekä yöheräilyt ja nukahtamisajankohta. Kovarianttina analyyseissä käytettiin sukupuolta, perheilmapiiriä, lapsen sairauksia sekä lapsen ruokintatapaa (rintaruokinta, maidonkorvike). Aineisto analysoitiin SPSS Statistics 25 -ohjelmistolla. Geneettinen aamutyyppisyys korreloi pitkään yöuneen kolmen (N=1066, BETA=.082, P=.012) sekä kahdeksan (N=975, BETA=.098, P=.002) kuukauden iässä. Myös varhainen nukahtamisaika (kellonaika) assosioitui aamutyyppisyyteen kahdeksan kuukauden iässä (N=1041, BETA=-0.72, P=.
  • Morales-Munoz, Isabel; Partonen, Timo; Saarenpää-Heikkilä, Outi; Kylliäinen, Anneli; Pölkki, Pirjo; Porkka-Heiskanen, Tarja; Paunio, Tiina; Paavonen, E. Juulia (2019)
    Background: Chronotype is a construct contributing to individual differences in sleep-wake timing. Previous studies with children have found that evening-types exhibit greater sleep difficulties. Infant sleep quality can be modulated by several factors, such as parental characteristics. We examined the association between parental circadian preference and sleep in early childhood. Methods: This study was based on a longitudinal birth cohort, with several measurement points. We used information regarding parental questionnaires during pregnancy and children's sleep measures at three, eight, 18 and 24 months. In total, 1220 mothers, 1116 fathers, 993 infants at three months, 990 infants at eight months, 958 children at 18 months, and 777 children at 24 months were analyzed. Parental circadian preference was measured using the Horne-Ostberg Morningness-Eveningness Questionnaire. Concerning children's sleep, we used the Brief Infant Sleep Questionnaire (BISQ) and the Infant Sleep Questionnaire (ISQ) at each time point. Results: Maternal circadian preference was associated with infants' circadian rhythm development at three, eight, 18 and 24 months. Furthermore, increased maternal eveningness was also related to short sleep during daytime at three months, and nighttime at three and eight months, to long sleep-onset latency at three, 18 and 24 months, to late bedtime at three, eight and 18 months, and to sleep difficulties at eight and 24 months. Paternal circadian preference was not associated with any sleep variable at any time point. Conclusion: Maternal circadian preference is related to several sleep difficulties in early childhood, and it may be considered a potential risk factor for the onset of early sleeping problems. (c) 2018 Elsevier B.V. All rights reserved.
  • Fernández-Marín, Beatriz; Atherton, Jon; Olascoaga, Beñat; Kolari, Pasi; Porcar Castell, Albert; García-Plazaola, José I. (2018)
    Subarctic plants in summer (subjected to continuous light) showed photosynthetic pigment contents mainly driven by PPFD (unrelated to day/night cycles) and a xanthophyll cycle responsiveness to PPFD exacerbated during night-times. Composition and content of photosynthetic pigments is finely tuned by plants according to a subtle equilibrium between the absorbed and used energy by the photosynthetic apparatus. Subarctic and Arctic plants are subjected to extended periods of continuous light during summer. This condition represents a unique natural scenario to study the influence of light on pigment regulation and the presence of diurnal patterns potentially governed by circadian rhythms. Here, we examined the modulation of the photosynthetic apparatus in three naturally co-occurring woody species: mountain birch (Betula pubescens ssp. czerepanovii), alpine bearberry (Arctostaphylos alpina) and Scots pine (Pinus sylvestris) around the summer solstice, at 67 A degrees N latitude. Plants were continuously exposed to solar radiation during the 3-day study period, although PPFD fluctuated, being lower during night-times. Photochemical efficiencies for a given PPFD were similar during daytime and night-time for the three species. In Scots pine, for a given PPFD, net assimilation was slightly higher during daytime than during night-time. Overall, the dynamism in pigment content was mainly driven by PPFD, and was generally unrelated to day/night cycles. Weak indications of potential circadian regulation were found over a few pigments only. Interestingly, the xanthophyll cycle was active at any time of the day in the three species but its responsiveness to PPFD was exacerbated during night-times. This was particularly evident for bearberry, which maintained a highly de-epoxidised state even at night-times. The results could indicate an incomplete acclimation to a 24-h photoperiod for these species, which have colonised subarctic latitudes only recently.