Sleep architecture modifications after double chronotherapy: A case series of bipolar depressed inpatients.

The aim of this study is to objectively evaluate sleep architecture changes of depressed bipolar subjects treated with chronoterapeutics. Eleven depressed bipolar inpatients received 3 cycles of Total Sleep Deprivation, followed by daily light therapy sessions for one week. Polysomnography was performed before and after the treatment. Depressive symptoms significantly reduced, and sleep architecture changed with significant differences in N2% and N3% and REM density. Change in N3% was also positively correlated to depressive symptoms reduction. Although, previous studies reported sleep architecture changes after chronoterapeutics in unipolar depression, this is the first study to demonstrate changes also in bipolar depressed subjects.

Antidepressant chronotherapeutics normalizes prefrontal 1H-MRS glutamate in bipolar depression.

BACKGROUND: Dysfunctional glutamatergic neurotransmission has been proposed both, as a biological underpinning of mood disorder and as a target for rapid-acting antidepressant treatments. Total sleep deprivation and light therapy (TSD + LT) can prompt antidepressant response in drug-resistant bipolar depression. Here we explored the effects of TSD + LT on dorsolateral prefrontal cortex (DLPFC) glutamate and/or glutamine+glutamate (Glx) levels. METHODS: We studied single voxel 1H-MRS measures of DLPFC Glu and Glx levels of 48 healthy participants and 55 inpatients with a major depressive episode in course of Bipolar Disorder, a subset of which (N = 23) underwent three cycles of repeated TSD + LT and were evaluated before and after treatment. Treatment effects of mood and on Glu and Glx concentrations were analyzed in the context of the Generalized Linear Model (GLM), correcting for age, sex and ongoing lithium treatment. RESULTS: Higher concentration of Glu (adjusted Z = -2189, p = 0,0285) and Glx (adjusted Z = -3,13, p = 0,0017) were observed in BD patients compared to HC. Treatment caused a significant rapid reduction of depressive symptom severity over time (F = 63.98, p < 0.01). Change in depression levels after TSD + LT treatment was significantly influenced by delta change in Glu levels (LR χ2 = 4.619, p = 0.0316) and in Glx levels (LR χ2 = 4.486, p = 0.0341). CONCLUSION: A reduction in Glu and Glx levels associated with depression could contribute to the mechanism of action of TSD + LT, directly acting on glutamatergic neurons, or to the interaction between the glutamatergic system and dopamine (DA) and serotonin (5-HT) levels, known to be targeted by TSD. This is in line with several studies showing a glutamatergic modulation effects of antidepressants and mood stabilizing agents. This finding deepens our understanding of antidepressant effect of chronoterapeutics.

Effective Antidepressant Chronotherapeutics (Sleep Deprivation and Light Therapy) Normalize the IL-1ß:IL-1ra Ratio in Bipolar Depression.

BACKGROUND: Mood disorders associate with peripheral markers of low-grade inflammation, among which circulating levels of interleukin-1ß (IL-1ß) consistently predict diagnosis and poor outcomes. Antidepressant chronotherapeutics (total sleep deprivation and light therapy, TSD+LT) prompts response in drug-resistant bipolar depression, but its effect on peripheral inflammation were never assessed. Here we explored the effects of TSD+LT on IL-1ß signaling. METHODS: We studied the ratio between IL-1ß and its receptor antagonist (IL-1ß:IL1ra) in 33 healthy participants, and in 26 inpatients with a major depressive episode in course of Bipolar Disorder, before and after treatment with three cycles of repeated TSD+LT, interspersed with sleep recovery nights, administered during 1 week. Treatment effects of mood and on IL-1ß:IL1ra were analyzed in the context of the Generalized Linear Model (GLM). RESULTS: At baseline, patients had higher IL-1ß, IL1ra, and IL-1ß:IL1ra than controls. Treatment significantly decreased IL-1ß:IL1ra, by decreasing IL-1ß and increasing IL1ra, the effect being proportional to baseline levels and normalizing values. Patients with higher baseline levels showed the highest decrease in IL-1ß:IL-1ra, which associated with the immediate antidepressant response at the first cycle; while patients with lower baseline values showed negligible changes in the IL-1ß:IL-1ra, unrelated to treatment response. CONCLUSION: We observed a parallel change of inflammatory biomarkers and severity of depression after chronotherapeutics, suggesting that a reduction in inflammation associated with depression could contribute to the mechanism of action of TSD+LT, and warranting interest for controlled studies addressing the role of inflammation in the recovery from bipolar depression.

Bright light therapy accelerates the antidepressant effect of repetitive transcranial magnetic stimulation in treatment resistant depression: a pilot study.

Objectives: We performed a randomized single-blinded study to assess the superiority of the combination strategy of repetitive Transcranial Magnetic Stimulation (rTMS) and Bright Light Therapy (BLT) over rTMS treatment alone in reducing depressive symptoms in treatment-resistant depression (TRD).Methods: We enrolled 80 inpatients with a diagnosis of TRD. All patients were randomly assigned into two groups: group A was treated with rTMS, compared to group B treated with a combination of rTMS and BLT. Depressive symptoms were weekly assessed (T0, T1, T2, T3) through the 17-item Hamilton depression rating scale (HDRS-17).Results: rANOVA (F=2.766, p=0.043) and post-hoc in HDRS-17 showed significant better scores in favour of group B every week (p<0.025, T1: 22.075 vs 17.200; T2: 16.100 vs 12.775; T3: 12.225 vs 8.900).Conclusions: The antidepressant effect of rTMS was enhanced and accelerated by its combination with BLT in treating resistant depression.KEYPOINTSAlmost one third of depressed patients does not respond to antidepressants; emerging neuromodulation and chronobiological techniques are effective antidepressant augmentation treatments.The aim of this study was to assess the superiority of the combination strategy of Light Therapy and TMS over TMS treatment alone in a group of treatment resistant depressed patients.The implication of this study in clinical practice is that a safe, low risk and cost-effective treatment, as Light Therapy, improves and accelerates the antidepressant effect of TMS.

Changes of white matter microstructure after successful treatment of bipolar depression.

BACKGROUND: Diffusion tensor imaging (DTI) measures suggest a widespread alteration of white matter (WM) microstructure in patients with bipolar disorder (BD). The chronotherapeutic combination of repeated total sleep deprivation and morning light therapy (TSD+LT) can acutely reverse depressive symptoms in approximately 60% of patients, and it has been confirmed as a model antidepressant treatment to investigate the neurobiological correlates of rapid antidepressant response. METHODS: We tested if changes in DTI measures of WM microstructure could parallel antidepressant response in a sample of 44 patients with a major depressive episode in course of BD, treated with chronoterapeutics for one week. We used both a tract-wise and a voxel-wise approach for the whole-brain extraction of DTI measures of WM microstructure: axial (AD), radial (RD), and mean diffusivity (MD), and fractional anisotropy (FA). RESULTS: Compared to baseline level, at one-week follow up we observed a significant increase in average FA measures paralleled by a significant decrease in MD measures of several WM tracts including cingulum, corpus callosum, corona radiata, cortico-spinal tract, internal capsule, fornix and uncinate fasciculus. The degree of change was associated to clinical response. CONCLUSIONS: This is the first study to show changes of individual DTI measures of WM microstructure in response to antidepressant treatment in BD. Our results add new evidence to warrant a role for chronotherapeutics as a first-line treatment for bipolar depression and contribute identifying generalizable neuroimaging-based biomarkers of antidepressant response.

Optimized light therapy for non-seasonal major depressive disorder: effects of timing and season.

BACKGROUND: Light Therapy (LT) when combined with standard antidepressant treatment for unipolar depression hastens recovery. We studied the influence of LT timing on the antidepressant efficacy of LT and the influence of the season of treatment and recurrence on the response to treatment. METHODS: We studied 70 inpatients affected by Unipolar Depression, treated for three weeks with combined LT and venlafaxine. Two-third of the patients received LT following a predictive algorithm based on MEQ scores; the others received LT at 11:00 a.m. Severity of depression was rated on the Hamilton Depression Rating Scale (HDRS). A subgroup of patients wore activity monitors. RESULTS: HDRS scores significantly decreased during treatment (Friedman's ANOVA: χ2=186.82, p<0.00001). LT administered in the early morning showed a better relative efficacy than late morning (F=4.576; p=0.012) with the clinical improvement correlating with an advance in rest-activity rhythm acrophase (r=-0.336; p=0.017). Season of hospitalization interacted with LT timing and time in influencing response to treatment (F=3.101; p=0.049) and season of episode recurrence significantly interacted with LT timing, season of hospitalization and time (F=5.925; p=0.0035). LIMITATIONS: The major limitation of the study is the small sample size when considering simultaneously LT schedules, season of treatment and recurrence. Moreover, even if none of the patients fulfilled DSM-IV criteria for seasonal pattern of recurrence, they were not administered any questionnaire about seasonality. CONCLUSIONS: We confirmed the usefulness of LT as a non-pharmacological antidepressant therapy for non-seasonal depression. Season and timing of administration and timing of the rest-activity cycle affected response to treatment.

Acute antidepressant response to sleep deprivation combined with light therapy is influenced by the catechol-O-methyltransferase Val(108/158)Met polymorphism.

Catechol-O-methyltransferase (COMT) inactivates norepinephrine and dopamine via methyl conjugation, and a G-A transition in the COMT gene (rs4680) influences the enzyme activity. It is a current area of debate whether rs4680 can influence antidepressant response in major depressive disorder, and whether this influence extends to bipolar depression. Chronotherapeutic interventions, such as sleep deprivation and light therapy, are multi-target in nature and are effective in bipolar depression. Here we studied the effect of rs4680 on response to sleep deprivation combined with light therapy (36 h awake followed by a night of undisturbed sleep, with 10,000 lx light administered for 30 min during the night awake and upon awakening) in 87 bipolar depressed inpatients. Patients who were homozygotic for the Val/Val variant showed a significantly less efficient antidepressant effect after the night awake than those who were heterozygotic and homozygotic for the Met variant. This effect of rs4680 is similar to its observed influence on response to serotonergic and noradrenergic drug treatments in major depressive disorder. This is the first study reporting an influence of rs4680 on antidepressant response in bipolar depression. This finding supports the hypothesis of a major role for catecholamines in the mechanism of action of chronotherapeutics, and for rs4680 in modulating this effect.

Phase advance is an actimetric correlate of antidepressant response to sleep deprivation and light therapy in bipolar depression.

The combination of total sleep deprivation (TSD) and light therapy (LT) in bipolar depression causes rapid antidepressant effects, and its mechanism of action has been hypothesized to involve the enhancement of all of the monoaminergic systems targeted by antidepressant drugs (serotonin, dopamine, norepinephrine). It is still unknown if the clinical effects are paralleled by changes in biological rhythms. In a before/after design of a study of biological correlates of response, 39 inpatients affected by Type I Bipolar Disorder whose current depressive episode was without psychotic features were treated for one week with repeated TSD combined with morning LT. Wrist actigraphy was recorded throughout the study. Two-thirds of the patients responded to treatment (50% reduction in Hamilton Depression score). Responders showed an increase in daytime activity, phase-advance of the activity-rest rhythm of 57 min compared to the pre-treatment baseline, and reduced nighttime sleep. Non-responders did not show significant changes in the parameters of their activity-rest rhythm. Phase advance of the activity-rest rhythm is an actimetric correlate of the antidepressant response to TSD and LT in bipolar depression. Results are consistent with the known effects of sleep-wake manipulations and neurotransmitter function on the suprachiasmatic nucleus.

Chronotherapeutics in a psychiatric ward.

Psychiatric chronotherapeutics is the controlled exposure to environmental stimuli that act on biological rhythms in order to achieve therapeutic effects in the treatment of psychiatric conditions. In recent years some techniques (mainly light therapy and sleep deprivation) have passed the experimental developmental phase and reached the status of powerful and affordable clinical interventions for everyday clinical treatment of depressed patients. These techniques target the same brain neurotransmitter systems and the same brain areas as do antidepressant drugs, and should be administered under careful medical supervision. Their effects are rapid and transient, but can be stabilised by combining techniques among themselves or together with common drug treatments. Antidepressant chronotherapeutics target the broadly defined depressive syndrome, with response and relapse rates similar to those obtained with antidepressant drugs, and good results are obtained even in difficult-to-treat conditions such as bipolar depression. Chronotherapeutics offer a benign alternative to more radical treatments of depression for the treatment of severe depression in psychiatric wards, but with the advantage of rapidity of onset.

Combined total sleep deprivation and light therapy in the treatment of drug-resistant bipolar depression: acute response and long-term remission rates.

BACKGROUND: Drug resistance remains a persistent source of morbidity and mortality for patients with bipolar depression. A growing number of clinical studies support the usefulness of chronotherapeutic interventions, such as total sleep deprivation (TSD) and light therapy (LT), in the treatment of nonresistant bipolar depression. METHOD: To investigate the clinical usefulness of TSD plus LT in the treatment of drug-resistant bipolar depression, we treated 60 inpatients for 1 week with repeated TSD and LT combined with ongoing antidepressants and lithium salts. All patients had a DSM-IV diagnosis of bipolar I disorder. Drug resistance was rated according to Thase and Rush criteria. The pattern of relapses and recurrences was assessed during a prospective 9-month follow-up. Data were gathered from September 2002 to July 2004. RESULTS: A 2-way repeated-measures analysis of variance with changes in self-rated perceived mood scores as dependent variable and with time and group (history of drug resistance) as independent factors confirmed significant time-by-group interaction (p = .0339). A logistic regression on rates of achievement of response (50% reduction in Hamilton Rating Scale for Depression ratings) confirmed the significance of observed differences: overall, 70% (23/33) of nonresistant versus 44% (12/27) of drug-resistant patients achieved response (p = .045). A survival time analysis (Cox proportional hazards model) showed that history of drug resistance significantly influenced the pattern of relapses and recurrences, with 57% (13/23) of nonresistant responders and 17% (2/12) of drug-resistant responders being euthymic after 9 months (p = .0212). DISCUSSION: The combination of repeated TSD and LT in drug-resistant patients was useful in triggering an acute response. Further clinical research is needed to optimize this treatment option for drug-resistant patients in the long term.

Antidepressant effects of light therapy combined with sleep deprivation are influenced by a functional polymorphism within the promoter of the serotonin transporter gene.

BACKGROUND: A functional polymorphism within the promoter of the serotonin transporter has been shown to influence the antidepressant response to serotonergic drug treatments and to total sleep deprivation (TSD). The short-term relapse that follows acute response to TSD has been successfully prevented by combining TSD with light therapy. The mechanism of action of this combined treatment is unknown. METHODS: We tested the hypothesis that allelic variation of the serotonin transporter (5-HTT) linked polymorphic region (5-HTTLPR) could influence the response to the combination of light therapy and TSD. Twenty-two bipolar depressed inpatients were administered a night of TSD combined with 30 min light therapy given during the TSD night and in the morning after recovery sleep. 5-HTTLPR was genotyped using polymerase chain reaction techniques. Changes in perceived mood were rated on a visual analog scale. RESULTS: Light therapy sustained the effect of TSD. The effect was more marked in homozygotes for the long variant of 5-HTTLPR than in heterozygotes and homozygotes for the short variant. CONCLUSIONS: The influence of 5-HTTLPR on response to the combination of TSD and light therapy is similar to that observed on response to TSD and serotonergic drug treatments.