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1.
Acta Psychiatr Scand ; 146(4): 350-356, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35876837

RESUMO

OBJECTIVE: Perinatal depression (PND) is a severe complication of pregnancy, affecting both mothers and newborns. Bright light therapy (BLT) has only been tested in a few studies for treating either antenatal or postnatal depression. We conducted a pilot trial to investigate the efficacy and safety of BLT for PND occurring at any time across the perinatal period. METHODS: A single-blind RCT was carried out in women with an EPDS >12 from the 2nd gestational trimester until 9 months postpartum. Participants received either 30-minutes morning BLT (10'000 lux) or dim red light (DRL, 19 lux) for 6 weeks. RESULTS: Twenty-two women were randomised to BLT (n = 11) or DRL (n = 11). Among those receiving BLT, 73% achieved remission (improvement ≥50%, EPDS score ≤ 12), in contrast to 27% in the DRL group (p = 0.04). A significant influence of time on EPDS score and group-time interaction emerged, with a greater reduction in the BLT-group across the follow-up period. No women in either group reported major side effects. CONCLUSION: Morning BLT induced a significant remission from PND as compared to DRL and this effect was maintained across the perinatal period. BLT showed an excellent safety profile and was well-tolerated, thus representing a valid therapeutic strategy in this vulnerable perinatal population.


Assuntos
Depressão Pós-Parto , Transtorno Depressivo , Depressão/terapia , Transtorno Depressivo/terapia , Feminino , Humanos , Recém-Nascido , Fototerapia/efeitos adversos , Projetos Piloto , Gravidez , Método Simples-Cego
2.
Nervenarzt ; 93(9): 892-900, 2022 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-35687164

RESUMO

BACKGROUND: Chronobiological processes play a critical role in the initial manifestation and course of affective disorders. Chronotherapeutic agents aim to improve sleep-wake cycle disturbances and affective symptoms by modulating the chronobiological neuronal circuitry. OBJECTIVE: To review the different chronotherapeutic procedures, the current evidence situation and recommendations for clinical applications. METHOD: Narrative review. RESULTS: Chronotherapeutic interventions for patients with affective disorders can be nonpharmacological, e.g., light therapy, sleep deprivation, sleep phase advance and dark therapy, pharmacological in the form of melatonin and psychological consisting of interpersonal and social rhythm therapy or cognitive behavioral therapy for insomnia modified for patients with bipolar disorder. Nearly all these interventions show promising data regarding their efficacy in acute depressive or manic episodes or as maintenance therapy. For melatonin, there is less evidence for improvement of affective symptoms than for stabilizing the sleep-wake cycle. Some interventions are well-suited for an outpatient setting, e.g., light therapy, dark therapy and psychotherapy, while others, such as triple chronotherapy consisting of sleep deprivation, sleep phase advance and light therapy, are more suited for in-patient treatment. CONCLUSION: Chronotherapeutic interventions are versatile in their application and can be combined with each other and used concomitantly with classical psychopharmacotherapy. With a benign side effect profile and good evidence for efficacy, they could play an important role in the treatment of affective disorders; however, this potential is used too rarely in the clinical context.


Assuntos
Transtorno Bipolar , Melatonina , Transtornos do Sono-Vigília , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/terapia , Cronoterapia/métodos , Humanos , Melatonina/uso terapêutico , Transtornos do Humor/diagnóstico , Transtornos do Humor/psicologia , Transtornos do Humor/terapia , Sono , Privação do Sono
3.
Praxis (Bern 1994) ; 110(2): 56-62, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35105211

RESUMO

Light therapy has become established as an evidence-based treatment for Seasonal Affective Disorder. Light impacts the timing and stability of circadian rhythms as expressed in sleep, mood, alertness, and cognition. Forty years of clinical trials and open treatment have led to guidelines for patient selection, using light alone or in combination with antidepressants (or lithium for bipolar depression). Mood and sleep disturbances can also respond to adjunct light therapy in a broader set of psychiatric, neurologic and medical illnesses. We specify criteria for choice of treatment devices: optimum dose (10,000 lux), spectrum (white light), exposure duration (30-60 minutes) and timing (early morning). Protocol adjustment requires continual monitoring with attention to rate of improvement and management of potential side effects.


Assuntos
Ritmo Circadiano , Fototerapia , Escuridão , Humanos , Luz , Sono
4.
Biochem Pharmacol ; 191: 114304, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33129807

RESUMO

Daylight is ubiquitous and is crucial for mammalian vision as well as for non-visual input to the brain via the intrinsically photosensitive retinal ganglion cells (ipRGCs) that express the photopigment melanopsin. The ipRGCs project to the circadian clock in the suprachiasmatic nuclei and thereby ensure entrainment to the 24-hour day-night cycle, and changes in daylength trigger the appropriate seasonal behaviours. The ipRGCs also project to the perihabenular nucleus and surrounding brain regions that modulate mood, stress and learning in animals and humans. Given that light has strong direct effects on mood, cognition, alertness, performance, and sleep, light can be considered a "drug" to treat many clinical conditions. Light therapy is already well established for winter and other depressions and circadian sleep disorders. Beyond visual and non-visual effects via the retina, daylight contributes to prevent myopia in the young by its impact on eye development, and is important for Vitamin D synthesis and bone health via the skin. The sun is the most powerful light source and, dependent on dose, its ultraviolet radiance is toxic for living organisms and can be used as a disinfectant. Most research involves laboratory-based electric light, without the dynamic and spectral changes that daylight undergoes moment by moment. There is a gap between the importance of daylight for human beings and the amount of research being done on this subject. Daylight is taken for granted as an environmental factor, to be enjoyed or avoided, according to conditions. More daylight awareness in architecture and urban design beyond aesthetic values and visual comfort may lead to higher quality work and living environments. Although we do not yet have a factual basis for the assumption that natural daylight is overall "better" than electric light, the environmental debate mandates serious consideration of sunlight not just for solar power but also as biologically necessary for sustainable and healthy living.


Assuntos
Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Luz , Fotoperíodo , Humanos , Transtornos do Humor/etiologia , Transtornos do Humor/metabolismo , Transtornos do Humor/prevenção & controle , Miopia/etiologia , Miopia/metabolismo , Miopia/prevenção & controle , Retina/metabolismo , Células Ganglionares da Retina/metabolismo , Opsinas de Bastonetes/metabolismo , Núcleo Supraquiasmático/metabolismo , Vitamina D/metabolismo
6.
Eur J Neurosci ; 51(1): 346-365, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30702783

RESUMO

Mood disorders are often characterised by alterations in circadian rhythms, sleep disturbances and seasonal exacerbation. Conversely, chronobiological treatments utilise zeitgebers for circadian rhythms such as light to improve mood and stabilise sleep, and manipulations of sleep timing and duration as rapid antidepressant modalities. Although sleep deprivation ("wake therapy") can act within hours, and its mood-elevating effects be maintained by regular morning light administration/medication/earlier sleep, it has not entered the regular guidelines for treating affective disorders as a first-line treatment. The hindrances to using chronotherapeutics may lie in their lack of patentability, few sponsors to carry out large multi-centre trials, non-reimbursement by medical insurance and their perceived difficulty or exotic "alternative" nature. Future use can be promoted by new technology (single-sample phase measurements, phone apps, movement and sleep trackers) that provides ambulatory documentation over long periods and feedback to therapist and patient. Light combinations with cognitive behavioural therapy and sleep hygiene practice may speed up and also maintain response. The urgent need for new antidepressants should hopefully lead to reconsideration and implementation of these non-pharmacological methods, as well as further clinical trials. We review the putative neurochemical mechanisms underlying the antidepressant effect of sleep deprivation and light therapy, and current knowledge linking clocks and sleep with affective disorders: neurotransmitter switching, stress and cortico-limbic reactivity, clock genes, cortical neuroplasticity, connectomics and neuroinflammation. Despite the complexity of multi-system mechanisms, more insight will lead to fine tuning and better application of circadian and sleep-related treatments of depression.


Assuntos
Transtornos do Humor , Sono , Antidepressivos/uso terapêutico , Ritmo Circadiano , Humanos , Transtornos do Humor/tratamento farmacológico , Privação do Sono/terapia
7.
Exp Gerontol ; 124: 110641, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31252161

RESUMO

Light is the most powerful "zeitgeber" signal to synchronize circadian sleep-wake cycles. In dementia, these rhythms are often fragmented - probably due to loss of neuronal function of the suprachiasmatic nuclei (the biological "master clock" in the brain) and/or weakness of external zeitgebers. We investigated the effects of a prototype dawn-dusk simulator (DDS) on circadian rest-activity cycles, sleep, mood and well-being in a balanced crossover design during fall and winter in 20 institutionalized patients with dementia (86 ±â€¯6 y, 17 f). All participants had one baseline week followed by exposure to individually timed DDS over their beds for 7-8 weeks. They spent 8 weeks without DDS as a control. Mood, self-reliant daily activity, social behavior, agitation, and quality of life were assessed by standardized questionnaires and visual analogue scales, regularly rated by trained caregivers. Circadian and sleep characteristics of their rest-activity cycles were analyzed by actimetry over 17 weeks. DDS exposure led to significantly better mood in the morning hours after waking. The effects were most pronounced in the second 4 weeks with DDS, indicating that positive effects emerged gradually. Differences in circadian rest-activity cycles and sleep were mainly age-dependent. We found statistically significant correlations between measures of higher quality of life and better mood, greater alertness and circadian rhythm stability. We conclude that continuous, long-term application of dawn-dusk simulation at the sleep-wake transitions appears to increase external zeitgeber strength in institutionalized patients with dementia. The DDS may provide an effective, non-invasive tool to improve mood and ameliorate patients' quality of life.


Assuntos
Ciclos de Atividade , Ritmo Circadiano , Demência/terapia , Fototerapia/métodos , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/terapia , Estudos Cross-Over , Feminino , Humanos , Masculino , Qualidade de Vida , Transtornos do Sono-Vigília/terapia , Suíça
8.
Gen Comp Endocrinol ; 258: 244-249, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28711512

RESUMO

Humans retain neurobiological responses to circadian day-night cycles and seasonal changes in daylength in spite of a life-style usually independent of dawn-dusk signals. Seasonality has been documented in many functions, from mood to hormones to gene expression. Research on seasonal affective disorder initiated the first use of timed bright light as therapy, a treatment since extended to non-seasonal major depression and sleep-wake cycle disturbances in many psychiatric and medical illnesses. The growing recognition that sufficient light is important for psychological and somatic well-being is leading to the development of novel lighting solutions in architecture as well as focus on a more conscious exposure to natural daylight.


Assuntos
Transtorno Afetivo Sazonal , Ritmo Circadiano/fisiologia , Humanos , Luz , Fototerapia/métodos , Transtorno Afetivo Sazonal/etiologia , Transtorno Afetivo Sazonal/fisiopatologia , Transtorno Afetivo Sazonal/terapia , Estações do Ano
9.
Psychol Med ; 48(10): 1694-1704, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29108526

RESUMO

BACKGROUND: When patients are admitted onto psychiatric wards, sleep problems are highly prevalent. We carried out the first trial testing a psychological sleep treatment at acute admission (Oxford Ward sLeep Solution, OWLS). METHODS: This assessor-blind parallel-group pilot trial randomised patients to receive sleep treatment at acute crisis [STAC, plus standard care (SC)], or SC alone (1 : 1). STAC included cognitive-behavioural therapy (CBT) for insomnia, sleep monitoring and light/dark exposure for circadian entrainment, delivered over 2 weeks. Assessments took place at 0, 2, 4 and 12 weeks. Feasibility outcomes assessed recruitment, retention of participants and uptake of the therapy. Primary efficacy outcomes were the Insomnia Severity Index and Warwick-Edinburgh Mental Wellbeing Scale at week 2. Analyses were intention-to-treat, estimating treatment effect with 95% confidence intervals. RESULTS: Between October 2015 and July 2016, 40 participants were recruited (from 43 assessed eligible). All participants offered STAC completed treatment (mean sessions received = 8.6, s.d. = 1.5). All participants completed the primary end point. Compared with SC, STAC led to large effect size (ES) reductions in insomnia at week 2 (adjusted mean difference -4.6, 95% CI -7.7 to -1.4, ES -0.9), a small improvement in psychological wellbeing (adjusted mean difference 3.7, 95% CI -2.8 to 10.1, ES 0.3) and patients were discharged 8.5 days earlier. One patient in the STAC group had an adverse event, unrelated to participation. CONCLUSIONS: In this challenging environment for research, the trial was feasible. Therapy uptake was high. STAC may be a highly effective treatment for sleep disturbance on wards with potential wider benefits on wellbeing and admission length.


Assuntos
Ritmo Circadiano/fisiologia , Terapia Cognitivo-Comportamental/métodos , Transtornos Mentais/terapia , Avaliação de Resultados em Cuidados de Saúde , Fototerapia/métodos , Transtornos do Sono-Vigília/terapia , Adulto , Estudos de Viabilidade , Feminino , Hospitais Psiquiátricos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Método Simples-Cego
10.
Curr Alzheimer Res ; 14(10): 1063-1075, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28545364

RESUMO

OBJECTIVE: We tested whether the effects of a dynamic lighting system are superior to conventional lighting on emotions, agitation behaviour, quality of life, melatonin secretion and circadian restactivity cycles in severely demented patients. As a comparison, an age matched control patient group was exposed to conventional lighting. For none of the output measures were significant differences between the two lighting conditions found during the 8 study weeks in fall/winter. METHODS: Thus, we divided the patient cohort (n = 89) into two groups, solely based on the median of their daily individual light exposure. Patients with higher average daily light exposure (>417 lx) showed significantly longer emotional expressions of pleasure and alertness per daily observations than patients with lower daily light exposure. Moreover, they had a higher quality of life, spent less time in bed, went to bed later and initiated their sleep episodes later, even though the two groups did not differ with respect to age, severity of cognitive impairment and mobility. In general, men were more agitated, had shorter sleep with more wake episodes, had a lower circadian amplitude of relative rest-wake activity and interdaily circadian stability than women. In particular, lower daily light exposures significantly predicted lower circadian amplitudes of rest-activity cycles in men but not in women. This may indicate sex specific susceptibility to daily light exposures for rest-activity regulation in older demented patients. RESULTS: Our results provide evidence that a higher daily light exposure has beneficial effects on emotions and thus improved quality of life in a severely demented patient group.


Assuntos
Demência/fisiopatologia , Demência/terapia , Iluminação , Fototerapia , Idoso , Idoso de 80 Anos ou mais , Ritmo Circadiano/efeitos da radiação , Estudos de Coortes , Emoções/efeitos da radiação , Feminino , Humanos , Masculino , Melatonina/análise , Pessoa de Meia-Idade , Atividade Motora/efeitos da radiação , Casas de Saúde , Qualidade de Vida , Descanso , Estudos Retrospectivos , Saliva/química , Sono/efeitos da radiação , Resultado do Tratamento
11.
Chronobiol Int ; 33(7): 810-20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27101434

RESUMO

We assessed salivary melatonin levels in renal transplant (RTx) recipients who participated in a randomised, multicentre wait-list controlled trial on the effect of bright light therapy on their sleep and circadian rhythms. A large proportion of RTx recipients in our cohort had unexpectedly low melatonin values, which precluded calculation of the dim-light melatonin onset (DLMO) as a circadian marker. Thus, the aim of this post hoc analysis was to describe the melatonin profile of home-dwelling RTx recipients diagnosed with sleep-wake disturbances (SWDs). The participants were characterised by means of sleep questionnaires, validated psychometric instruments [Pittsburgh sleep quality Index (PSQI), Epworth sleepiness scale (ESS), Morningness-Eveningness Questionnaire (MEQ) and Depression, Anxiety and Stress Scale (DASS)] in addition to melatonin assay in saliva. Data were analysed with descriptive statistics and group comparisons made with appropriate post hoc tests. RTx recipients [n = 29 (aged 54.83 ± 13.73, transplanted 10.62 ± 6.84 years ago)] were retrospectively grouped into two groups: RTx recipients whose dim light melatonin onset (DLMO) could be calculated (n = 11) and those whose DLMO could not be calculated (n = 18). RTx recipients having a measurable DLMO had a number of differences from those without DLMO: they were younger [46.4 ± 14.9 compared to 60.0 ± 10.3 (p = .007)], had higher haemoglobin values [135.36 ± 12.01 versus 122.82 ± 11.56 (p = .01)], less anxiety [4 (0;8) versus 12 (6.5;14) (p = .021)] and a better overall sense of coherence [SOC Score: 71.09 ± 12.78 versus 56.28 ± 15.48 (p = 0.013)]. These results suggest that RTx recipients whose DLMO could be calculated have less health impairments, underlying the relevance of a stable circadian system.


Assuntos
Ritmo Circadiano/fisiologia , Transplante de Rim , Melatonina/metabolismo , Transtornos do Sono-Vigília/metabolismo , Sono/fisiologia , Adulto , Idoso , Feminino , Humanos , Luz , Masculino , Pessoa de Meia-Idade , Saliva/metabolismo , Inquéritos e Questionários
12.
Transpl Int ; 28(1): 59-70, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25182079

RESUMO

This study assessed the effect and feasibility of morning bright light therapy (BLT) on sleep, circadian rhythms, subjective feelings, depressive symptomatology and cognition in renal transplant recipients (RTx) diagnosed with sleep-wake disturbances (SWD). This pilot randomized multicentre wait-list controlled trial included 30 home-dwelling RTx randomly assigned 1:1 to either 3 weeks of BLT or a wait-list control group. Morning BLT (10 000 lux) was individually scheduled for 30 min daily for 3 weeks. Wrist actimetry (measuring sleep and circadian rhythms), validated instruments (subjective feelings and cognition) and melatonin assay (circadian timing) were used. Data were analysed via a random-intercept regression model. Of 30 RTx recipients (aged 58 ± 15, transplanted 15 ± 6 years ago), 26 completed the study. While BLT had no significant effect on circadian and sleep measures, sleep timing improved significantly. The intervention group showed a significant get-up time phase advance from baseline to intervention (+24 min) [(standardized estimates (SE): -0.23 (-0.42; -0.03)] and a small (+14 min) but significant bedtime phase advance from intervention to follow-up (SE: -0.25 (-0.41; -0.09). Improvement in subjective feelings and depressive symptomatology was observed but was not statistically significant. Bright light therapy showed preliminary indications of a beneficial effect in RTx with sleep-wake disturbances. (ClinicalTrials.gov number: NCT01256983).


Assuntos
Ritmo Circadiano , Falência Renal Crônica/cirurgia , Transplante de Rim , Luz , Fototerapia/métodos , Sono , Adulto , Índice de Massa Corporal , Cognição , Transtornos Cognitivos/fisiopatologia , Feminino , Humanos , Masculino , Melatonina/sangue , Pessoa de Meia-Idade , Projetos Piloto , Glândula Pineal/metabolismo , Análise de Regressão , Fatores de Tempo , Listas de Espera , Punho
13.
J Pers Disord ; 27(5): 680-96, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22928852

RESUMO

Individuals with borderline personality disorder (BPD) frequently suffer from sleep disturbances. The authors investigated circadian rhythms, sleep, and well-being in women with BPD in their habitual life conditions during 3 weeks with morning light therapy (LT) and 3 weeks without LT (oLT). Sleep-wake cycles were measured using wrist actimetry, proximal skin temperature as an indirect index of relaxation, as well as weekly salivary melatonin to document the internal circadian rhythm phase. Questionnaires assessed clinical state throughout the 6-week protocol. Ten matched healthy women followed the same 6-week protocol without light treatment. Women with BPD had significantly worse subjective sleep quality and reduced daytime alertness compared to controls. Sleep-wake cycles in BPD ranged from highly disturbed to extremely regular patterns. Melatonin and proximal skin temperature profiles revealed appropriate synchronization of the circadian system with the sleep-wake cycle in most BPD women and in all controls. Morning LT significantly phase-advanced activity in BPD compared to oLT, shortened sleep duration, decreased movement time, and increased skin temperature during sleep (a marker of relaxation). Although general depression scores and borderline symptoms did not change, daytime alertness improved with morning LT, and atypical depression scores were attenuated. Morning LT is a potential adjunct treatment for BPD.


Assuntos
Transtorno da Personalidade Borderline/fisiopatologia , Transtorno da Personalidade Borderline/terapia , Ritmo Circadiano/fisiologia , Fototerapia/métodos , Qualidade de Vida , Sono/fisiologia , Vigília/fisiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Melatonina/análise , Monitorização Fisiológica , Saliva/química , Temperatura Cutânea , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
15.
J Clin Psychiatry ; 72(7): 986-93, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21535997

RESUMO

OBJECTIVE: Affective disorder during pregnancy is a common condition requiring careful judgment to treat the depression while minimizing risk to the fetus. Following up on promising pilot trials, we studied the efficacy of light therapy. METHOD: Twenty-seven pregnant women with nonseasonal major depressive disorder according to DSM-IV (outpatients, university polyclinic) were randomly assigned to 7,000 lux fluorescent bright white or 70 lux dim red (placebo) light administered at home in the morning upon awakening for 1 h/d in a 5-week double-blind trial carried out between October 2004 and October 2008. Clinical state was monitored weekly with the 29-item Structured Interview Guide for the Hamilton Depression Rating Scale (HDRS) with Atypical Depression Supplement (SIGH-ADS). Changes of rating scale scores over time were analyzed with the general linear model. Differences from baseline of SIGH-ADS and 17-item HDRS scores at every time point were the dependent variables, time was the within-subjects factor, and treatment was the between-subjects factor. The model also included baseline score of depression and gestational age at intervention start. RESULTS: The superiority of bright light over dim light placebo was shown for both SIGH-ADS (R² = 0.251; F(3,23) = 3.91; P < .05) and HDRS (R² = 0.338; F(3,23) = 5.42; P < .01) when analyzing the week-by-week change from baseline, and HDRS scores showed a significant interaction of treatment with time (F(4,92) = 2.91; P < .05). Categorical analysis revealed that the response rate (HDRS ≥ 50% improvement) at week 5 was significantly greater for bright light (81.3%, n = 16) than for placebo light (45.5%, n = 11) (P < .05). Remission (final score ≤ 8) was attained by 68.6% versus 36.4%, respectively (P < .05). Expectation ratings did not differ significantly between groups. CONCLUSIONS: Bright white light treatment for 5 weeks improved depression during pregnancy significantly more than placebo dim red light. The study provides evidence that light therapy, a simple, cost-effective antidepressant modality with minimal side effects for the mother and no known risk for the unborn child, may be a useful nonpharmacologic approach in this difficult situation. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01043289.


Assuntos
Transtorno Depressivo Maior/terapia , Fototerapia , Complicações na Gravidez/terapia , Adolescente , Adulto , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/psicologia , Método Duplo-Cego , Feminino , Humanos , Inventário de Personalidade/estatística & dados numéricos , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/psicologia , Psicometria , Suíça , Adulto Jovem
16.
J Biol Rhythms ; 26(1): 55-67, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21252366

RESUMO

Reliable detection of circadian phase in humans using noninvasive ambulatory measurements in real-life conditions is challenging and still an unsolved problem. The masking effects of everyday behavior and environmental input such as physical activity and light on the measured variables need to be considered critically. Here, we aimed at developing techniques for estimating circadian phase with the lowest subject burden possible, that is, without the need of constant routine (CR) laboratory conditions or without measuring the standard circadian markers, (rectal) core body temperature (CBT), and melatonin levels. In this validation study, subjects (N = 16) wore multi-channel ambulatory monitoring devices and went about their daily routine for 1 week. The devices measured a large number of physiological, behavioral, and environmental variables, including CBT, skin temperatures, cardiovascular and respiratory function, movement/posture, ambient temperature, and the spectral composition and intensity of light received at eye level. Sleep diaries were logged electronically. After the ambulatory phase, subjects underwent a 32-h CR procedure in the laboratory for measuring unmasked circadian phase based on the "midpoint" of the salivary melatonin profile. To overcome the complex masking effects of confounding variables during ambulatory measurements, multiple regression techniques were applied in combination with the cross-validation approach to subject-independent prediction of circadian phase. The most accurate estimate of circadian phase was achieved using skin temperatures, irradiance for ambient light in the blue spectral band, and motion acceleration as predictors with lags of up to 24 h. Multiple regression showed statistically significant improvement of variance of prediction error over the traditional approaches to determining circadian phase based on single predictors (motion acceleration or sleep log), although CBT was intentionally not included as the predictor. Compared to CBT alone, our method resulted in a 40% smaller range of prediction errors and a nonsignificant reduction of error variance. The proposed noninvasive measurement method could find applications in sleep medicine or in other domains where knowing the exact endogenous circadian phase is important (e.g., for the timing of light therapy).


Assuntos
Ritmo Circadiano , Monitorização Ambulatorial/métodos , Algoritmos , Temperatura Corporal , Humanos , Luz , Masculino , Melatonina/metabolismo , Análise de Regressão , Reprodutibilidade dos Testes , Saliva/metabolismo , Temperatura Cutânea , Sono/fisiologia , Fatores de Tempo , Vigília/fisiologia
18.
Dialogues Clin Neurosci ; 10(3): 337-43, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18979947

RESUMO

Diurnal variation of depressive symptoms appears to be part of the core of depression. Yet, longitudinal investigation of an individual's pattern, regularity, relation to clinical state, and clinical improvement reveals little homogeneity. Morning lows, afternoon slump, evening worsening-all can occur during a single depressive episode. Mood variability, or the propensity to produce mood swings, appears to be the characteristic that most predicts capacity to respond to treatment. Laboratory studies have revealed that mood, like physiological variables such as core body temperature, is regulated by a circadian clock interacting with the sleep homeostat. Many depressed patients, particularly bipolar patients, show delayed sleep phase (late chronotype). Even small shifts in the timing and duration of sleep affect mood state (sleep deprivation and sleep phase advance have an antidepressant effect). The implications for treatment are to stabilize mood state by enhancing synchronization of the sleep-wake cycle with the biological clock (eg, with light therapy).


Assuntos
Ritmo Circadiano/fisiologia , Depressão/fisiopatologia , Humanos
19.
Chronobiol Int ; 25(1): 51-64, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18293149

RESUMO

Seasonal Affective Disorder (SAD) patients crave and eat more carbohydrates (CHO) in fall-winter when depressed, especially in the evenings, and feel energetic thereafter. Evening CHO-rich meals can phase delay circadian rhythms, and glucose increases retinal response to light. We studied timed CHO- or protein-rich (PROT) diet as a putative therapy for SAD. Unmedicated, DSM-IV-diagnosed depressed women with SAD (n=22, 19-63 yrs) in the follicular phase of the menstrual cycle (present in 19) were randomized to nine days of eating approximately 1600 kcal of either CHO before 12:00 h (n=9), CHO after 18:00 h (n=6), or PROT after 18:00 h (n=7); only water was allowed for the rest of the day. Measurements included the depression questionnaire SIGH-SAD (with 21-item Hamilton depression subscale), Eating Behavior Questionnaire (DEBQ), percentage fat (by bioimpedancemetry), clinical biochemistry (glucose, cholesterol, triglycerides, TSH, T4, cortisol), and electroretinogram (ERG). No differential effects of diet were found on any of the studied parameters (except DEBQ). Clinically, participants improved slightly; the 21-HDRS score (mean+/-SD) decreased from 19.6+/-6.4 to 14.4+/-7.4 (p=.004). Percent change correlated significantly with menstrual day at diet onset (mood improved the first week after menstruation onset), change in available sunshine (more sunlight, better mood), and initial percentage fat (fatter patients improved more). Scotopic ERG amplitude was diminished after treatment (p=.025, three groups combined), probably due to greater exposure to sunshine in 14/22 subjects (partial correlation analysis significant). Keeping in mind the limitations of this ambulatory study (i.e., inability to control outdoor light exposure, small number of participants, and briefness of intervention), it is suggested that the 25% clinical improvement (of the order of magnitude of placebo) is not related to nutrient diet or its timing, but rather to natural changes during the menstrual cycle, available sunshine, and ease of dieting for fatter patients.


Assuntos
Depressão/dietoterapia , Dieta , Carboidratos da Dieta/uso terapêutico , Proteínas Alimentares/uso terapêutico , Fotofobia/dietoterapia , Transtorno Afetivo Sazonal/dietoterapia , Adolescente , Adulto , Afeto/efeitos da radiação , Idoso , Depressão/fisiopatologia , Depressão/psicologia , Comportamento Alimentar , Feminino , Humanos , Ciclo Menstrual/fisiologia , Pessoa de Meia-Idade , Transtorno Afetivo Sazonal/fisiopatologia , Transtorno Afetivo Sazonal/psicologia , Luz Solar , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento
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