Phototherapy in individuals with and without subsyndromal seasonal affective disorder

Antidepressant and energizing effects of bright light exposure (phototherapy) have been widely reported to occur in patients with seasonal affective disorder. We have attempted to evaluate whether other segments of the population might benefit from phototherapy, most notably individuals with subsyndromal seasonal affective disorder, as well as healthy individuals with no winter difficulties (controls). We have studied 20 subjects in each of these two categories and have found that bright artificial light did not alter mood and behavior in controls. In contrast, individuals with subsyndromal seasonal affective disorder responded favorably to treatment with bright environmental light. A dose of 5 hours of bright light exposure, divided between morning and evening, was more effective than 2 hours of exposure. This finding may have practical implications for establishing optimal environmental lighting conditions for those individuals whose winter difficulties do not meet criteria for seasonal affective disorder.     

Antidepressant effects of light in seasonal affective disorder

The authors treated winter depression in 13 patients with typical seasonal affective disorder by extending the length of winter days with bright and dim light in the morning and evening in a balanced-order crossover study. Bright light had a marked antidepressant effect, whereas the dim light did not. This response could not be attributed to sleep deprivation. Subsequent pilot studies indicated that bright evening light alone is probably also effective. Several patients were able to maintain the antidepressant response throughout the winter months by continuing daily light treatments.     

Bright light therapy of subsyndromal seasonal affective disorder in the workplace: morning vs. afternoon exposure

OBJECTIVE: Bright light therapy in seasonal affective disorder (SAD) has been studied extensively. However, little attention has been given to subsyndromal seasonal affective disorder (SSAD) or the use of bright light in the workplace. Many patients using bright light boxes complain of the inconvenience of use. Much of this inconvenience involves the often-recommended early timing of the bright light therapy. Patients, who already have difficulty awakening, often have difficulty using the bright light therapy soon after awakening before going to work. If bright light could be used effectively in the workplace, the treatment would be more convenient; the improved convenience would probably improve compliance. In this study, we studied the effectiveness of bright light therapy in subjects with SSAD in the workplace, comparing morning bright light with afternoon bright light. METHOD: Morning and afternoon bright light treatment (2500 lux) were compared in 30 subsyndromal seasonal affective disorder patients using the bright light therapy in the workplace. Hamilton Depression Ratings and subjective measures of mood, energy, alertness and productivity were assessed before and after 2 weeks of light therapy. RESULTS: Both morning and evening bright light significantly decreased the depression ratings and improved the subjective mood, energy, alertness and productivity scores. However, there were no significant differences between the two times of administration of the bright light treatment. Both bright light treatments were well tolerated. CONCLUSION: Bright light given in the workplace improves subjective ratings of mood, energy, alertness and productivity in SSAD subjects. Morning and afternoon bright lights resulted in similar levels of improvement.     

Effects of light therapy on neuropsychological function and mood in seasonal affective disorder.

To date, little attention has been paid to changes in neuropsychological function in seasonal affective disorders (SAD). In this study, we investigated the performance of 30 patients with SAD on a wide range of cognitive variables before and after 2 weeks of light treatment with either white or placebo red light, as well as later in the summertime. Performance of subjects with SAD on neuropsychological tests was compared with a group of 29 age- and education-matched healthy control subjects. The most consistent deficits associated with SAD were on tests of cognitive failures, visual memory, and visual-construction skills. In contrast to specific bright light effects on psychiatric measures, reports of cognitive failures did not change with either light treatment. Visual memory and constructional deficits responded nonspecifically to treatment with either white or the presumed placebo red light. Surprisingly, visual memory deficits were seen again in the summer, at a time when mood, cognitive failures, and other cognitive functions appeared at normal levels. These data suggest that cognitive functioning is affected by SAD. In addition, light treatment may have differential effects on mood and cognition.     

Increased vagal tone during winter in subsyndromal seasonal affective disorder.

BACKGROUND: Seasonal affective disorder (SAD) is characterized by recurrent winter depression with summer remissions and/or hypomania. Further symptoms include hypersomnia, increased appetite, weight gain, fatigue, and social withdrawal, which may indicate autonomic changes during winter. METHODS: Measurements of respiratory sinus arrhythmia, heart rate (HR), and skin conductance level (SCL) were taken from 32 participants in subsyndromal SAD and control groups (eight male and eight female subjects in each group) in autumn and winter to determine any change in autonomic function. Measures were taken at baseline and during two stressor tasks. Single determinations of blood pressure, sublingual temperature, depression, aerobic fitness, and body mass index were also measured at each session. Replication in a second data collection period over subsequent winter and spring periods was conducted with an additional 32 participants to extend the findings and to counterbalance order effects in testing. Data were combined to produce "winter" and "nonwinter" test periods and statistically corrected for testing order. RESULTS: Respiratory sinus arrhythmia differences indicated that SAD subjects have increased vagal tone in winter. Both groups show a decrease for HR and increases for SCL and diastolic blood pressure in winter. CONCLUSIONS: Seasonal affective disorder may show similarities with hibernation, and the results may indicate mechanisms different from those of nonseasonal depression.     

Seasonal and mood independence of low basal prolactin secretion in premenopausal women with seasonal affective disorder

To test hypotheses of opposing roles of dopamine and serotonin in prolactin secretion in seasonal affective disorder, the authors determined basal serum prolactin concentrations for premenopausal women, eight with and 14 without seasonal affective disorder, in late afternoon during the follicular phase of the menstrual cycle (and a subgroup during the luteal phase) in winter and summer. Despite their significantly higher Hamilton depression scale scores in winter than in summer, the patients had significantly lower prolactin concentrations than the control subjects in both seasons. These results suggest that low prolactin secretion may be a trait characteristic in seasonal affective disorder.     

The effects of nefazodone on women with seasonal affective disorder: clinical and polysomnographic analyses

OBJECTIVE: To outline the clinical and polysomnographic changes induced by nefazodone in patients with seasonal affective disorder. METHODS: Twelve patients were enrolled, and 9 of them studied, in an open-label trial with objective and subjective measurements. The mean age of the studied patients was 45 (range 35-58) years. They met Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV), criteria for major depressive disorder and current major depressive episode with seasonal patterns. The patients' mean baseline score on the Seasonal Patterns Assessment Questionnaire (SPAQ) was 15.7 (standard deviation [SD] 5.3). The total nefazodone treatment period was 8 weeks, and the daily dosages were 100 mg in week 1, 200 mg in week 2, 300 mg in week 3, and up to 400 mg in weeks 4-8. Each patient received the 29-item version of the Hamilton Rating Scale for Depression (HAM-D), the Hamilton Rating Scale for Anxiety (HAM-A) and 2-night polysomnographic assessments on 3 occasions: before treatment (baseline, W0), at the end of week 4 (W4) and at the end of week 8 (W8). RESULTS: There were statistically significant improvements in depression, anxiety, sleep latency and sleep efficiency during the 8-week treatment protocol. Repeated-measures analysis of variance results indicated that nefazodone has a time-dependent effect on both HAM-D and HAM-A scores. After 8 weeks of nefazodone therapy, HAM-D scores decreased from 33.4 (SD 8.1) to 11.6 (SD 5.6) (F(2,14) = 13.68, p = 0.001) and HAM-A decreased from 26.6 (SD 7.0) to 11.5 (SD 11.1) (F(2,14) = 13.46, p = 0.001). The results of paired t tests show that, compared with baseline, HAM-D and HAM-A scores decreased at both W4 (p = 0.004 and p = 0.002, respectively) and W8 (p = 0.002 and p = 0.005, respectively). The time-dependent effects on stage 1 sleep (F(2,16) = 6.06, p = 0.011) and periodic leg movement index (F(2,16) = 4.31, p = 0.035) were also significant. The mean sleep latency of these patients decreased from 39.9 (SD 32.7) minutes at W0 to 16.6 (SD 15.3) minutes at W8 (p < 0.05). Sleep efficiency increased from 78.8% (SD 14.6%) at W0 to 91.5% (SD 5.5%) at W8 (p < 0.05). Stage 1 sleep decreased from 4.9% (SD 1.9%) at W0 to 3.4% (SD 2.6%) at W8 (p < 0.05). CONCLUSIONS: The results of this preliminary study indicate that nefazodone not only has favourable antidepressant and anxiolytic effects but also enhances sleep efficiency and sleep latency.     

Treatment of seasonal affective disorder with morning light

Three subjects afflicted with seasonal affective disorder (winter depression) were treated with 2-hour morning light exposures. Within 2 to 5 days, all responded, and remission of their symptoms was sustained during the 2-month treatment period.     

Treatment of seasonal affective disorder with green light and red light

OBJECTIVE: This study sought to determine whether an equal photon density of green light is superior to red light in treating seasonal affective disorder. METHOD: After recruitment through the media, 20 outpatients with seasonal affective disorder participated in a balanced-order crossover trial of 1 week of green light therapy compared with 1 week of red light therapy. Each treatment consisted of 2 hours of daily light treatment at home in the early morning. Ultraviolet light was excluded from both treatment conditions. The photon densities of the two treatments (2.3 x 10(15) photons/sec per cm2) were similar to those used in previous studies of therapy with 2500-lux white light. Fourteen patients completed the study. At least 1 week separated each treatment period to allow time for relapse. Effectiveness of treatment was assessed by analysis of variance of changes in ratings on the Hamilton Rating Scale for Depression. RESULTS: Although patients' expectations of the two treatments were similar, green light induced greater antidepressant effects than red light. A Sequence by Color interaction was also demonstrated. CONCLUSIONS: Green light provides a treatment effect superior to that of red light and similar to that seen in previous studies with white light. These results are consistent with the hypothesis that retinal photoreceptors mediate the antidepressant response in seasonal affective disorder. Identifying optimal wavelengths for light treatment is important in optimizing phototherapy efficacy.     

Phototherapy in subsyndromal seasonal affective disorder (S-SAD) and "diagnosed" controls

Antidepressant and energizing effects of bright light exposure have been widely reported to occur in patients with seasonal affective disorder (SAD). In order to evaluate whether other segments of the population might also benefit from this treatment, we studied 20 normal individuals with mild SAD-like symptoms (subsyndromal SAD, S-SAD) and 20 with no reported seasonal difficulties (non-S-SAD). Whereas S-SAD individuals benefited from phototherapy, non-S-SAD normals did not. This finding raises the questions of whether a history of seasonal problems might be a marker of vulnerability to affective episodes and if S-SAD individuals might be considered as a high risk population in this regard.     

Treatment of seasonal affective disorder with light: preliminary Australian experience

Six patients with a history of Seasonal Affective Disorder (SAD) were treated with bright artificial light. Patients presented with at least two consecutive years of loss of energy, difficulty in working, loss of interest in activities, difficulty in concentrating, increased somnolence, over-eating (carbohydrate craving) and depressed mood. All received seven consecutive days of full-spectrum bright light with an intensity greater than 2,500 lux at a distance of three feet. Evening exposure for two hours resulted in significant clinical improvement. The main improvements were a return to normal sleeping patterns, a reduction in eating habits, improved energy level, a desire to continue with interests and activities and an improvement in mood. Possible mechanisms for the clinical effects of bright light treatment are discussed.     

Growth hormone response to baclofen in patients with seasonal affective disorder: effects of light therapy

There is evidence for gamma-aminobutyric acid (GABA) dysfunction in the pathophysiology and treatment response of patients with major depression, but this has not been studied in seasonal affective disorder (SAD). Growth hormone (GH) response to a challenge with a GABAB receptor agonist, baclofen, is considered an in vivo index of hypothalamic GABAB receptor function in humans. To explore the role of GABAB receptor function in SAD, we compared the GH response to baclofen challenge in 15 patients with SAD and 20 matched healthy controls. Of the 15 patients with SAD, 14 had repeat baclofen challenge following 2-week treatment with light therapy. The results showed that baclofen administration led to a significant increase in GH release both in patients with SAD and normal controls. There was no significant difference in the GH response to baclofen between the two groups. Furthermore, 2-week treatment with light therapy did not significantly alter the baclofen-induced GH response in patients with SAD, in spite of a clear therapeutic effect. The results of this study suggest that hypothalamic GABAB receptor function, as measured by baclofen induced GH release, is not altered in patients with SAD or by light therapy.     

Seasonal mood symptoms in bulimia nervosa and seasonal affective disorder.

Mood and appetite disturbances are commonly found in bulimia nervosa and seasonal affective disorder (SAD). To investigate seasonality of mood symptoms, we administered the Seasonal Pattern Assessment Questionnaire (SPAQ) to 38 consecutive bulimic patients, 38 age- and sex-matched SAD patients, and 25 age- and sex-matched normal controls. The SPAQ is a reliable, retrospective, self-rated questionnaire that assesses seasonal changes in mood, sleep, weight, and social activity. The SAD patients had significantly higher Global Seasonality Scores (GSS) than the bulimic patients, who had higher scores than the control group (F = 78.6, df = 2.98, P less than .0001). Forty-two percent of bulimics met case-finding SPAQ criteria for SAD, compared with none of the control group (chi 2 = 14.1, df = 1, P less than .0005). These data suggest that a significant number of unselected bulimic patients have seasonal mood symptoms as severe as that seen in SAD. We propose that a common neurobiologic abnormality, such as serotonergic dysfunction, may underlie the common symptoms found in bulimia and SAD.     

An open trial of light therapy for women with seasonal affective disorder and comorbid bulimia nervosa

OBJECTIVE: Many patients with seasonal affective disorder (SAD) have dysfunctional eating behaviors. Conversely, many women with bulimia nervosa have marked winter worsening of mood and bulimic symptoms. Controlled studies of light therapy in SAD and in bulimia nervosa have shown beneficial effects on mood and binge/purge symptoms. We explored the clinical use of light therapy in women with SAD who also had comorbid bulimia nervosa. METHOD: Twenty-two female patients diagnosed using DSM-IV criteria with both bulimia nervosa and major depressive disorder with a seasonal (winter) pattern were treated with an open design, 4-week trial of light therapy (10,000 lux fluorescent light box with an ultraviolet filter, 30 to 60 minutes per day in the early morning). Patients were assessed before and after treatment with depression scales and with binge/purge diaries. RESULTS: Light therapy resulted in significant improvement in mood, with a mean 56% reduction in 29-item Hamilton Rating Scale for Depression scores following treatment (p < .001). The frequency of binges and purges per week also significantly decreased (p < .001) from baseline by a mean of 46% and 36%, respectively. Two (9%) of 22 patients became abstinent of binge/ purge episodes, compared with 10 (45%) of 22 patients who met criteria for remission of depressive symptoms. The light therapy was well tolerated by patients. CONCLUSION: These results suggest that therapeutic effects of light therapy on mood and bulimic symptoms in patients with SAD and comorbid bulimia nervosa are sustained over at least 4 weeks. However, the low abstinence rate in bulimic symptoms indicates that light therapy may be most effectively used as an adjunctive treatment to medications and/or psychotherapy for bulimia nervosa.     

Adaptation to dim light in depressed patients with seasonal affective disorder

Supersensitivity to light has been suggested as a possible trait marker for manic-depressive illness. Because winter seasonal affective disorder (SAD) is associated with depressive episodes during dark winter days, the authors postulated that SAD patients would show diminished sensitivity to dim light. Dark-adaptation curves were obtained in 10 medication-free, depressed SAD patients and in 10 age- and sex-matched drug-free healthy controls. Contrary to the hypothesis, patients adapted to dim light more rapidly than controls.     

Early response to light therapy partially predicts long-term antidepressant effects in patients with seasonal affective disorder

OBJECTIVE: To determine if the antidepressant effect of 1 hour of light therapy is predictive of the response after 1 and 2 weeks of treatment in patients with seasonal affective disorder (SAD). PATIENTS: Twelve patients with SAD. SETTING: National Institutes of Health Clinical Center, Bethesda, Md. INTERVENTIONS: Light therapy for 2 weeks. OUTCOME MEASURES: Scores on the Seasonal Affective Disorder Version of the Hamilton Depression Rating Scale (SIGH-SAD) on 4 occasions (before and after 1 hour of light therapy and after 1 and 2 weeks of therapy) in the winter when the patients were depressed. Change on typical and atypical depressive scores at these time points were compared. RESULTS: Improvement of atypical depressive symptoms after 1 hour of light therapy positively correlated with improvement after 2 weeks of therapy. CONCLUSION: In patients with SAD, the early response to light therapy may predict some aspects of long-term response to light therapy, but these results should be treated with caution until replicated.     

Premenstrual depression in women with a history of affective disorder: mood and attentional processes

Survey studies have pinpointed high concordance rates between affective disorder and premenstrual depression. This relationship was investigated in women with a history of both disorders. Sixteen subjects rated symptoms daily during one menstrual cycle, and were assessed on measures of mood and selective attention pre- and postmenstrually. Prospective ratings confirmed premenstrual depression in only eight of the subjects. These subjects demonstrated a significant premenstrual elevation in dysphoric affect, yet exhibited a dysphoric attentional bias both pre- and postmenstrually. These data do not suggest an interactive relationship between affective disorder and premenstrual depression along the particular cognitive dimension of study.     

Dimensions of temperament and bright light response in seasonal affective disorder

Scale scores on the Tridimensional Personality Questionnaire (TPQ)-novelty seeking (NS), harm avoidance (HA), and reward dependence (RD)-can predict response to antidepressants. This study examined 89 patients with Bipolar Disorder (I, II) or Major Depressive Disorder, both with recurrent winter seasonal pattern. The TPQ was administered while the patients were depressed, following 10-14 days of bright light therapy (30 min, 10,000 lux) and after spontaneous springtime remission. The Structured Interview Guide for the Hamilton Depression Rating Scale-Seasonal Affective Disorder Version (SIGH-SAD) assessed the severity of depression. At baseline, there were no significant differences between diagnostic subgroups or responders and non-responders on the TPQ or SIGH-SAD scales, though baseline RD scores were significantly higher in women than men. Furthermore, neither severity of depression nor magnitude of post-treatment clinical improvement was significantly correlated with baseline TPQ scores. Only HA scores decreased after treatment, with responders showing the greatest effect. HA scores also decreased from the baseline to springtime assessments for the group as a whole, with no difference between responders and non-responders. This is the first study to demonstrate that HA is state- rather than trait-dependent in seasonal affective disorder. The TPQ dimensions of temperament do not predict response to light therapy.