Changes of clinical pattern in seasonal affective disorder (SAD) over time in a German-speaking sample

Depression and Hypersomnia: A Complex Association

Hypersomnolence is a clinically defined syndrome characterized by the association of prolonged nocturnal sleep, impaired arousal quality, and sleep inertia. Hypersomnolence is the major feature of central hypersomnias and is frequently reported in various mood disorders, such as major depressive disorder, bipolar disorder, or seasonal affective disorder. Assessment of hypersomnolence is challenging in depressed patients, with objective tests often in the normal range despite a high level of sleepiness complaint. On the other hand, many patients with central hypersomnias reported depressive symptoms. The self-assessment of mood symptoms in patients with central hypersomnias may overdiagnose depression with an overlap between both conditions.

Hypersomnolence, Hypersomnia, and Mood Disorders

Relationships between symptoms of hypersomnolence, psychiatric disorders, and hypersomnia disorders (i.e., narcolepsy and idiopathic hypersomnia) are complex and multidirectional. Hypersomnolence is a common complaint across mood disorders; however, patients suffering from mood disorders and hypersomnolence rarely have objective daytime sleepiness, as assessed by the current gold standard test, the Multiple Sleep Latency Test. An iatrogenic origin of symptoms of hypersomnolence, and sleep apnea syndrome must be considered in a population of psychiatric patients, often overweight and treated with sedative drugs. On the other hand, psychiatric comorbidities, especially depression symptoms, are often reported in patients with hypersomnia disorders, and an endogenous origin cannot be ruled out. A great challenge for sleep specialists and psychiatrists is to differentiate psychiatric hypersomnolence and a central hypersomnia disorder with comorbid psychiatric symptoms. The current diagnostic tools seem to be limited in that condition, and further research in that field is warranted.

Epidemiology and socioeconomic impact of seasonal affective disorder in Austria

BACKGROUND

Seasonal affective disorder (SAD) is a subtype of recurrent depressive or bipolar disorder that is characterized by regular onset and remission of affective episodes at the same time of the year. The aim of the present study was to provide epidemiological data and data on the socioeconomic impact of SAD in the general population of Austria.

METHODS

We conducted a computer-assisted telephone interview in 910 randomly selected subjects (577 females and 333 males) using the Seasonal Health Questionnaire (SHQ), the Seasonal Pattern Assessment Questionnaire (SPAQ), and the Sheehan Disability Scale (SDS). Telephone numbers were randomly drawn from all Austrian telephone books and transformed using the random last digits method. The last birthday method was employed to choose the target person for the interviews.

RESULTS

Out of our subjects, 2.5% fulfilled criteria for the seasonal pattern specifier according to DSM-5 and 2.4% (95% CI=1.4-3.5%) were diagnosed with SAD. When applying the ICD-10 criteria 1.9% (95% CI=0.9-2.8%) fulfilled SAD diagnostic criteria. The prevalence of fall-winter depression according to the Kasper-Rosenthal criteria was determined to be 3.5%. The criteria was fulfilled by 15.1% for subsyndromal SAD (s-SAD). We did not find any statistically significant gender differences in prevalence rates. When using the DSM-5 as a gold standard for the diagnosis of SAD, diagnosis derived from the SPAQ yielded a sensitivity of 31.8% and a specificity of 97.2%. Subjects with SAD had significantly higher scores on the SDS and higher rates of sick leave and days with reduced productivity than healthy subjects.

CONCLUSIONS

Prevalence estimates for SAD with the SHQ are lower than with the SPAQ. Our data are indicative of the substantial burden of disease and the socioeconomic impact of SAD. This epidemiological data shows a lack of gender differences in SAD prevalence. The higher rates of females in clinical SAD samples might, at least in part, be explained by lower help seeking behaviour in males.

Treatment of seasonal affective disorder

Seasonal affective disorder (SAD), winter type, is characterized by the regular annual onset of major depressive episodes during fall or winter, followed by spontaneous remission and sometimes hypomanic or manic episodes during spring and summer. SAD is clinically important, since approximately 2-5% of the general population in temperate climates are affected. Since the first description of the syndrome, researchers have made attempts to elucidate the pathophysiological background of SAD. Bright light therapy has been proposed as the treatment of choice for this disorder. However, numerous studies have also investigated suitable psychopharmacological treatments for SAD. This report is aimed to provide an overview on the clinical management and current therapeutic options for SAD.

Hypersomnia and depressive symptoms: methodological and clinical aspects

The associations between depressive symptoms and hypersomnia are complex and often bidirectional. Of the many disorders associated with excessive sleepiness in the general population, the most frequent are mental health disorders, particularly depression. However, most mood disorder studies addressing hypersomnia have assessed daytime sleepiness using a single response, neglecting critical and clinically relevant information about symptom severity, duration and nighttime sleep quality. Only a few studies have used objective tools such as polysomnography to directly measure both daytime and nighttime sleep propensity in depression with normal mean sleep latency and sleep duration. Hypersomnia in mood disorders, rather than a medical condition per se, is more a subjective sleep complaint than an objective finding. Mood symptoms have also been frequently reported in hypersomnia disorders of central origin, especially in narcolepsy. Hypocretin deficiency could be a contributing factor in this condition. Further interventional studies are needed to explore whether management of sleep complaints improves mood symptoms in hypersomnia disorders and, conversely, whether management of mood complaints improves sleep symptoms in mood disorders.

Treatment of seasonal affective disorders

Seasonal affective disorder (SAD) is a subform of major depressive disorder, recurrent, or bipolar disorder with a regular onset of depressive episodes at a certain time of year, usually the winter. The treatment of SAD is similar to that of other forms of affective disorder, except that bright light therapy is recommended as the first-line option. Light therapy conventionally involves exposure to visible light of at least 2500 lux intensity at eye level. The effects of light therapy are thought to be mediated exclusively by the eyes, not the skin, although this assumption has not yet been verified. Morning light therapy has proven to be superior to treatment regimens in the evening. Response rates to light therapy are about 80% in selected patient populations, with atypical depressive symptoms being the best predictor of a favorable treatment outcome. Data from randomized, controlled trials suggest that antidepressants are effective in the treatment of SAD. Three double-blind, placebo-controlled trials have been conducted showing promising results for the selective serotonin reuptake inhibitors (SSRIs) sertraline and fluoxetine, as well as for moclobemide, a reversible inhibitor of monoamine oxidase A.

Imaging of seasonal affective disorder and seasonality effects on serotonin and dopamine function in the human brain

According to current knowledge, disturbances in brain monoamine transmission play a major role in many psychiatric disorders, and many of the radioligands used for investigating these disorders bind to targets within the brain monoamine systems. However, a phylogenetically ancient and prevailing function of monoamines is to mediate the adaptation of organisms and cells to rhythmical changes in light conditions, and to other environmental rhythms, such as changes in temperature, or the availability of energy resources throughout the seasons. The physiological systems mediating these changes are highly conserved throughout species, including humans. Here we review the literature on seasonal changes in binding of monoaminergic ligands in the human brain. Moreover, we argue for the importance of considering possible effects of season when investigating brain monoamines in healthy subjects and subjects with psychiatric disorders.

Bright-light therapy in the treatment of mood disorders

Bright-light therapy (BLT) is established as the treatment of choice for seasonal affective disorder/winter type (SAD). In the last two decades, the use of BLT has expanded beyond SAD: there is evidence for efficacy in chronic depression, antepartum depression, premenstrual depression, bipolar depression and disturbances of the sleep-wake cycle. Data on the usefulness of BLT in non-seasonal depression are promising; however, further systematic studies are still warranted. In this review, the authors present a comprehensive overview of the literature on BLT in mood disorders. The first part elucidates the neurobiology of circadian and seasonal adaptive mechanisms focusing on the suprachiasmatic nucleus (SCN), the indolamines melatonin and serotonin, and the chronobiology of mood disorders. The SCN is the primary oscillator in humans. Indolamines are known to transduce light signals into cells and organisms since early in evolution, and their role in signalling change of season is still preserved in humans: melatonin is synthesized primarily in the pineal gland and is the central hormone for internal clock circuitries. The melatonin precursor serotonin is known to modulate many behaviours that vary with season. The second part discusses the pathophysiology and clinical specifiers of SAD, which can be seen as a model disorder for chronobiological disturbances and the mechanism of action of BLT. In the third part, the mode of action, application, efficacy, tolerability and safety of BLT in SAD and other mood disorders are explored.

General and comparative efficacy and effectiveness of antidepressants in the acute treatment of depressive disorders: a report by the WPA section of pharmacopsychiatry

Current gold standard approaches to the treatment of depression include pharmacotherapeutic and psychotherapeutic interventions with social support. Due to current controversies concerning the efficacy of antidepressants in randomized controlled trials, the generalizability of study findings to wider clinical practice and the increasing importance of socioeconomic considerations, it seems timely to address the uncertainty of concerned patients and relatives, and their treating psychiatrists and general practitioners. We therefore discuss both the efficacy and clinical effectiveness of antidepressants in the treatment of depressive disorders. We explain and clarify useful measures for assessing clinically meaningful antidepressant treatment effects and the types of studies that are useful for addressing uncertainties. This includes considerations of methodological issues in randomized controlled studies, meta-analyses, and effectiveness studies. Furthermore, we summarize the differential efficacy and effectiveness of antidepressants with distinct pharmacodynamic properties, and differences between studies using antidepressants and/or psychotherapy. We also address the differential effectiveness of antidepressant drugs with differing modes of action and in varying subtypes of depressive disorder. After highlighting the clinical usefulness of treatment algorithms and the divergent biological, psychological, and clinical efforts to predict the effectiveness of antidepressant treatments, we conclude that the spectrum of different antidepressant treatments has broadened over the last few decades. The efficacy and clinical effectiveness of antidepressants is statistically significant, clinically relevant, and proven repeatedly. Further optimization of treatment can be helped by clearly structured treatment algorithms and the implementation of psychotherapeutic interventions. Modern individualized antidepressant treatment is in most cases a well-tolerated and efficacious approach to minimize the negative impact of otherwise potentially devastating and life-threatening outcomes in depressive disorders.

Climatic relationships with specific clinical subtypes of depression

Studies on the relationship between climate and unipolar depression rates have yielded mixed results, which could be attributed to the inclusion of heterogeneous clinical samples and the use of admission rather than onset dates. This study aimed to overcome these methodological issues. During an 8-year timeframe, onset rates of unipolar depressive episodes requiring hospitalization from individuals living up to 15 km from a selected meteorological station were stratified by clinical subtypes and modeled as Autoregressive Integrated Moving Average (ARIMA) functions of orthogonal climatic factors obtained by Principal Components Analysis (PCA). For comparison purposes, onset rates stratified by demographic factors and by diagnosis of Seasonal Affective Disorder (SAD) and admission rates were also modeled. The main findings were a negative 1-month delayed relationship between onset rates of episodes with melancholic features and a climatic factor mainly composed of ambient temperature/sunlight, and a negative 1-month delayed relationship between onset rates of episodes with psychotic features and a climatic factor mainly composed of barometric pressure. Results of this study support a climatic-rather than seasonal-influence in specific subtypes of depression. If replicated, they may have nosological and therapeutic implications.

Season of birth in siblings of patients with seasonal affective disorder. A test of the parental conception habits hypothesis

Recently we have published a report on seasonally varying birth rates in 553 patients with seasonal affective disorder (SAD). The present study is aimed to test the hypothesis of an idiosyncratic seasonal conception pattern of the parents of these patients to explain this phenomenon. We conducted a telephone interview with the patients to obtain information on the birth data of their siblings. Using the method of chart review to acquire information on the family history of our patients, we excluded those siblings with psychiatric disorders. We first compared the birth months and the quarters of birth of 435 healthy siblings with the general population. Secondly, we compared the birth distribution of the index SAD patients with that of their siblings. There was a significant deviation between the birth distribution of the siblings and the general population calculated on a monthly basis (p = 0.044). When comparing quarters we found less births than expected in the first (-14.1%) and fourth quarter of the year (-15.1%) and an excess of births in the second (+7.7%) and third quarter (+21.1%; p = 0.018). There were no significant differences between the group of SAD patients and their siblings regarding their birth patterns as calculated by months (p = 0.848) or quarters (p = 0.320). Our study provides support for the hypothesis of specific parental conception habits underlying the birth seasonality in SAD. Further research could be conducted in non-seasonal depression as there is still a lack of studies on seasonality of birth in affective disorders.

Serum lipid levels in seasonal affective disorder

Previous research has assessed the relationship between blood lipid levels and depression with contradictory results. Several studies have linked low cholesterol levels with impulsive, aggressive and suicidal behaviours. The aim of this pilot study was to examine serum lipids in a sample of patients suffering from seasonal affective disorder (SAD). We conducted a retrospective analysis of data on total serum cholesterol and serum triglycerides in 39 SAD patients and 40 non-seasonally depressed or schizophrenic control subjects. Study subjects had to be free of psychotropic drugs for at least 2 weeks. Analysis of covariance (ANCOVA) was performed to assess group differences. After adjustment for significant covariates SAD patients had significantly lower total cholesterol levels (5.21 +/- 1.14 mmol/l) than control subjects (5.94 +/- 1.11 mmol/l; p = 0.013). Moreover, hypercholesterolemia (total cholesterol > 5.20 mmol/l) was significantly less frequent in the SAD group (46.2%) than in the control group (75.0%; p = 0.012). Total serum triglycerides did not differ significantly between SAD patients (1.54 +/- 1.07 mmol/l) and controls (1.56 +/- 0.96 mmol/l; p = 0.126). The results of this study support the idea that low cholesterol levels may be of pathogenetic importance in SAD. Further study in larger clinical samples is warranted to clarify our findings.

The diagnosis, symptomatology, and epidemiology of seasonal affective disorder

The operational criteria for seasonal affective disorder (SAD) have undergone several changes since first proposed in 1984. SAD is currently included as a specifier of either bipolar or recurrent major depressive disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. The International Classification of Diseases, Tenth Edition has provisional diagnostic criteria for SAD. The most characteristic quality of SAD is that the symptoms usually present during winter and remit in the spring. Furthermore, the symptoms tend to remit when the patients are exposed to daylight or bright light therapy. The cognitive and emotional symptoms are as in other types of depression but the vegetative symptoms are the reverse of classic depressive vegetative symptoms, namely increased sleep and increased appetite. SAD is a common condition, but the exact prevalence rates vary between different studies and countries and is consistently found to be more common in women and in youth. SAD probably possibly occurs in children although not as commonly as in young adults. Some studies have found that certain ethnic groups who live at high northern latitudes may have adapted to the long arctic winter.

Pharmacotherapy of seasonal affective disorder

Seasonal affective disorder is a common variant of recurrent major depressive disorder or bipolar disorder. Treatment with bright artificial light has been found to be effective in this condition. However, for patients who do not respond to light therapy or those who lack compliance, conventional drug treatment with antidepressants also has been proposed. Substances with selective serotonergic or noradrenergic mechanisms should be preferred over older antidepressants. Although there are a number of open and controlled studies evaluating different compounds, these studies were often limited by relatively small sample sizes. Furthermore, there are no studies specifically addressing bipolar seasonal depression. This article will review the published literature on pharmacotherapy of seasonal affective disorder.

Bright light therapy in seasonal affective disorder--does it suffice?

Bright light therapy (BLT) has been proposed as treatment of choice for seasonal affective disorder (SAD). However, conventional antidepressants have also been found to be effective in this condition. We examined the psychopharmacologic medication in a clinical sample of 553 SAD patients, who had been treated with BLT, to assess the importance of drug treatment and to critically question the effectiveness of BLT. Forty-nine percent of our patients received psychopharmacologic treatment and about one third (35.4%) was treated with antidepressants, suggesting that BLT does not suffice as only antidepressant regimen for all SAD patients. Furthermore, our results show that only few patients with bipolar affective disorder were willing to accept long-term medication. Opposed to treatment guidelines, patients with several depressive episodes did not receive antidepressant maintenance medication or mood stabilizers more often than patients with only a few episodes.