Light therapy for seasonal affective disorder in primary care: randomised controlled trial

Treatment measures for seasonal affective disorder: A network meta-analysis

OBJECTIVE

The purpose of this study was to assess the potential effectiveness of several mainstream therapies, including phototherapy, antidepressants, cognitive-behavioral therapy, and negative ion generators, in the treatment of Seasonal Affective Disorder (SAD).

METHODS

A systematic search of PubMed, Embase, Cochrane, and WOS databases was conducted from January 1975 to December 3, 2022. Randomized controlled trials meeting predefined selection criteria for the treatment of SAD using mainstream therapeutic approaches were identified. After reviewing abstracts, data were synthesized and categorized based on the type of intervention and the targeted disorder.

RESULTS

A total of 21 randomized controlled trials, involving 1037 participants, were included. The standardized mean difference of depression scores and corresponding 95 % confidence intervals were calculated to assess the efficacy of phototherapy for Seasonal Affective Disorder. The meta-analysis revealed that phototherapy was significantly more effective than other intervention groups or control therapies, with an effect size of 4.64(2.38,7.03). Subgroup analysis demonstrated that no factors could explain the significant heterogeneity observed. Phototherapy exhibited statistically significant mild to moderate therapeutic effects in alleviating depressive symptoms and can be considered as a clinical therapy for treating Seasonal Affective Disorder. However, the quality of evidence remains low, and further well-designed, larger sample size, and high-quality studies are needed to confirm the efficacy of phototherapy in treating Seasonal Affective Disorder.

CONCLUSION

In conclusion, our systematic review and meta-analysis indicate that bright light therapy is a promising first-line non-pharmacological treatment for Seasonal Affective Disorder (SAD), showing significant improvement in mood symptoms compared to placebo. The findings support the use of bright light therapy as an effective and well-tolerated intervention for SAD. However, further large-scale, multicenter randomized controlled trials with long-term follow-up are needed to assess the long-term efficacy and safety of different treatment approaches for SAD.

"Shedding Light on Light": A Review on the Effects on Mental Health of Exposure to Optical Radiation

In relation to human health and functioning, light, or more specifically optical radiation, plays many roles, beyond allowing vision. These may be summarized as: regulation of circadian rhythms; consequences of direct exposure to the skin; and more indirect effects on well-being and functioning, also related to lifestyle and contact with natural and urban environments. Impact on mental health is relevant for any of these specifications and supports a clinical use of this knowledge for the treatment of psychiatric conditions, such as depression or anxiety, somatic symptom disorder, and others, with reference to light therapy in particular. The scope of this narrative review is to provide a summary of recent findings and evidence on the regulating functions of light on human beings’ biology, with a specific focus on mental health, its prevention and care.

Efficacy of light therapy for a college student sample with non-seasonal subthreshold depression: An RCT study

BACKGROUND

Light therapy has been successfully used to treat seasonal and non-seasonal depression, but there is limited evidence for its efficacy in subthreshold depression. This study examines the efficacy of light therapy for symptoms of depression and anxiety in non-seasonal subthreshold depression.

METHODS

College students with non-seasonal subthreshold depression were recruited. The participants were randomly allocated to one of the three conditions: high- (LT-5000 lux) and low-intensity (LT-500 lux) light therapy conditions and a waiting-list control condition (WLC). The primary outcome was Hamilton Depression Rating Scale (HAMD), and secondary outcomes were Beck Depression Inventory-II (BDI-II) and state anxiety inventory (SAI), which were assessed at baseline (Week 0), during the trial (Week 4), and after completion of the light therapy (Week 8).

RESULTS

A total of 142 participants completed the trial. The LT-5000 (effect size [d] = 1.56, 95% CI: 1.15 to 1.98) and LT-500 conditions (d = 0.84, 95% CI: 0.43 to 1.26) were significantly superior to the WLC condition. For the LT-5000, LT-500, and WLC conditions by the end of the 8-week trial, a response on the HAMD was achieved by 70.0%, 42.0% and 19.0% of the participants, and remission was achieved by 76.0%, 54.0%, and 19.0%, respectively.

LIMITATIONS

The subjects were not followed up regularly after completion of the trial.

CONCLUSION

Light therapy, both at high- and low-intensity, was efficacious in the treatment of college students with non-seasonal subthreshold depression. High-intensity light therapy was superior to low-intensity light therapy by the end of an 8-week trial.

The Efficacy of Light Therapy in the Treatment of Seasonal Affective Disorder: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Bright light therapy (BLT) has been used as a treatment for seasonal affective disorder (SAD) for over 30 years. This meta-analysis was aimed to assess the efficacy of BLT in the treatment of SAD in adults.

METHOD

We performed a systematic literature search including randomized, single- or double-blind clinical trials investigating BLT (≥1,000 lx, light box or light visor) against dim light (≤400 lx) or sham/low-density negative ion generators as placebo. Only first-period data were used from crossover trials. The primary outcome was the post-treatment depression score measured by validated scales, and the secondary outcome was the rate of response to treatment.

RESULTS

A total of 19 studies finally met our predefined inclusion criteria. BLT was superior over placebo with a standardized mean difference of -0.37 (95% CI: -0.63 to -0.12) for depression ratings (18 studies, 610 patients) and a risk ratio of 1.42 (95% CI: 1.08-1.85) for response to active treatment (16 studies, 559 patients). We found no evidence for a publication bias, but moderate heterogeneity of the studies and a moderate-to-high risk of bias.

CONCLUSIONS

BLT can be regarded as an effective treatment for SAD, but the available evidence stems from methodologically heterogeneous studies with small-to-medium sample sizes, necessitating larger high-quality clinical trials.

Precision Light for the Treatment of Psychiatric Disorders

Circadian timekeeping can be reset by brief flashes of light using stimulation protocols thousands of times shorter than those previously assumed to be necessary for traditional phototherapy. These observations point to a future where flexible architectures of nanosecond-, microsecond-, and millisecond-scale light pulses are compiled to reprogram the brain's internal clock when it has been altered by psychiatric illness or advanced age. In the current review, we present a chronology of seminal experiments that established the synchronizing influence of light on the human circadian system and the efficacy of prolonged bright-light exposure for reducing symptoms associated with seasonal affective disorder. We conclude with a discussion of the different ways that precision flashes could be parlayed during sleep to effect neuroadaptive changes in brain function. This article is a contribution to a special issue on Circadian Rhythms in Regulation of Brain Processes and Role in Psychiatric Disorders curated by editors Shimon Amir, Karen Gamble, Oliver Stork, and Harry Pantazopoulos.

Controlled trial evaluation of exposure duration to negative air ions for the treatment of seasonal affective disorder

This study evaluated the effectiveness of 30 or 60min of daily exposure to high-density or to zero-density (placebo condition) negative air ions over 18 days on the symptoms of seasonal affective disorder (SAD) in 40 participants under controlled laboratory conditions. Exposure to high-density negative air ions was superior to zero-density negative air ions in alleviating depression and the atypical symptoms of SAD. Also, more subjects in the high-density negative air ions groups met two different clinical response criteria than did those in the zero-density groups. Within the high density treatment group, both the short and long daily exposure reduced SAD symptoms. Exposure to negative air ions produced no negative side effects, and no ozone was produced by the ion generators. In both the high-density negative air ions and zero-density negative air ions groups, a significant placebo effect was found for most clinical measures. Finally, for the high-density negative air ion groups, subjects with a morningness chronotype responded better to treatment with high-density negative air ions than did those with an eveningness chronotype.

Bright white light therapy in depression: A critical review of the evidence

BACKGROUND

Light therapy is an accepted treatment option, at least for seasonal affective disorder (SAD). Our aim was to critically evaluate treatment effects of bright white light (BWL) on the depressive symptoms in both SAD and non-seasonal depression.

METHODS

The systematic review was performed according to the PRISMA guidelines. PubMed, Embase, and PsycINFO were searched (December 1974 through June 2014) for randomized controlled trials published in peer-reviewed journals. Study quality was assessed with a checklist developed by the Swedish Council on Technology Assessment in Health Care. Only studies with high or medium quality were used in the meta-analyses.

RESULTS

Eight studies of SAD and two studies of non-seasonal depression met inclusion and quality criteria. Effects on SAD were estimated in two meta-analyses. In the first, week by week, BWL reached statistical significance only at two and three weeks of treatment (Standardized Mean Difference, SMD: -0.50 (-CI 0.94, -0.05); -0.31 (-0.59, -0.03) respectively). The second meta-analysis, of endpoint data only, showed a SMD of -0.54 (CI: -0.95, -0.13), which indicates an advantage for BWL. No meta-analysis was performed for non-seasonal depression due to heterogeneity between studies.

LIMITATIONS

This analysis is restricted to short-term effects of BWL measured as mean changes in scores derived from SIGH-SAD, SIGH-SAD self-report, or HDRS rating scales.

CONCLUSIONS

Most studies of BWL have considerable methodological problems, and the results of published meta-analyses are highly dependent on the study selection. Even though quality criteria are introduced in the selection procedures of studies, when the results are carefully scrutinized, the evidence is not unequivocal.

Seasonal Affective Disorder (SAD): Role of Lamotrigine Augmentation to Anti-Depressant Medication in Winter Depression

BACKGROUND

Many therapeutic options have been evaluated and tried for seasonal affective disorder (SAD) including bright light therapy (BLT), anti-depressants, beta-blockers and psychotherapy, but the data supporting use of mood-stabilizing agents is just handful in spite of this condition being understood most frequently to be associated with bipolar affective disorder II (BPAD II). So we planned to study role of Lamotrigine (Mood stabilizing agent) in SAD.

MATERIALS AND METHODS

30 patients of SAD who were prescribed lamotrigine in addition to antidepressant medications for a minimum of 8 weeks and were assessed for severity using HAM-D were selected retrospectively from the hospital records for this study. HAM-D scores at 2, 4 and 8 weeks were compared to baseline scores.

STATISTICS ANALYSIS

Single tailed t-test was used to study the difference of means to assess the therapeutic response and pre/post analysis of change. Statistical significance was set at P < 0.05.

RESULTS

Though no significant difference was seen in HAM-D Scores at 2 weeks of treatment compared to baseline, but results were statistically significant at 4 and 8 weeks of treatment with lamotrigine augmentation of antidepressant medications.

CONCLUSION

We conclude that lamotrigine augmentation was found to be effective treatment strategy for managing winter depression phase of Seasonal Affective Disorder.

Verbal memory impairment in new onset bipolar disorder: Relationship with frontal and medial temporal morphology

OBJECTIVES

Verbal memory (VM) impairment is a trait feature of bipolar I disorder (BDI) that is present at illness onset and associated with functional outcome. However, little is known about the morphological abnormalities underlying this deficit early in the disease course. This study examined the neurobiological correlates of VM impairment in euthymic newly diagnosed patients, with attention to frontal and medial temporal (MT) structures known to contribute to VM.

METHODS

Euthymic patients with BDI recently recovered from their first episode of mania (n = 42) were compared with healthy subjects (n = 37) using measures of the California Verbal Learning Test (CVLT-II) associated with frontal and MT functioning. A subset of participants had 3T MRI scan (n = 31 patient group, n = 30 healthy subject group). Hippocampal and prefrontal volumes were analyzed using FreeSurfer 5.1 and correlated with their corresponding CVLT-II subscores.

RESULTS

Patients showed decreased performance in total learning as well as short and long delay verbal recall. Consistent with MT dysfunction, they also showed deficits in recognition discriminability and learning slope. In the patient group only, left hippocampal volumes were negatively correlated with these measures.

CONCLUSIONS

These results suggest that anomalous MT functioning is involved with VM impairment early in the course of BDI.

Complementary and alternative medicine therapies for perinatal depression

Complementary and alternative medicine therapies are increasingly sought out by people with psychiatric disorders. In this chapter, we review the evidence for several commonly used CAM therapies (i.e. omega-3 fatty acids, folate, S-adenosyl-methionine, St John's Wort, bright light therapy, exercise, massage, and acupuncture) in the treatment of perinatal depression. A number of these treatments may be reasonable to consider for women during pregnancy or postpartum, but the safety and efficacy of these relative to standard treatments must still be systematically determined. Evidence-based use of complementary and alternative medicine therapies treatments for perinatal depression is discussed. Adequately powered systematic studies are necessary to determine the role of complementary and alternative medicine therapies in the treatment of perinatal depression.

Air ions and mood outcomes: a review and meta-analysis

BACKGROUND

Psychological effects of air ions have been reported for more than 80 years in the media and scientific literature. This study summarizes a qualitative literature review and quantitative meta-analysis, where applicable, that examines the potential effects of exposure to negative and positive air ions on psychological measures of mood and emotional state.

METHODS

A structured literature review was conducted to identify human experimental studies published through August, 2012. Thirty-three studies (1957-2012) evaluating the effects of air ionization on depression, anxiety, mood states, and subjective feelings of mental well-being in humans were included. Five studies on negative ionization and depression (measured using a structured interview guide) were evaluated by level of exposure intensity (high vs. low) using meta-analysis.

RESULTS

Consistent ionization effects were not observed for anxiety, mood, relaxation/sleep, and personal comfort. In contrast, meta-analysis results showed that negative ionization, overall, was significantly associated with lower depression ratings, with a stronger association observed at high levels of negative ion exposure (mean summary effect and 95% confidence interval (CI) following high- and low-density exposure: 14.28 (95% CI: 12.93-15.62) and 7.23 (95% CI: 2.62-11.83), respectively). The response to high-density ionization was observed in patients with seasonal or chronic depression, but an effect of low-density ionization was observed only in patients with seasonal depression. However, no relationship between the duration or frequency of ionization treatment on depression ratings was evident.

CONCLUSIONS

No consistent influence of positive or negative air ionization on anxiety, mood, relaxation, sleep, and personal comfort measures was observed. Negative air ionization was associated with lower depression scores particularly at the highest exposure level. Future research is needed to evaluate the biological plausibility of this association.

A randomized, placebo-controlled trial of bright light and high-density negative air ions for treatment of Seasonal Affective Disorder

This study, conducted over the course of 5 years, assessed the antidepressant efficacy of two active treatments, bright white light and high-density negative ions, and the efficacy of two placebo treatments, dim red light and low-density negative ions, for Seasonal Affective Disorder (SAD). In a controlled laboratory setting, 73 women with SAD were exposed to one of the four treatment conditions over 12 consecutive days. Pretreatment expectation ratings did not significantly differ among the four treatment groups; however, expectation scores and treatment benefits were positively related. Over the course of treatment, subjects in all four groups showed significant score decreases on the Structured Interview Guide for the Hamilton Depression Rating Scale-Seasonal Affective Disorder Version-Self Rating (SIGH-SAD-SR) and on the Beck Depression Inventory (BDI). For raw scale scores, neither main effects of treatment nor interactions between treatment and time were significant. When remission outcome criteria were used, bright white light was significantly more effective than any of the other three treatments, and exposure to high-density negative ions was more effective than either of the two placebo conditions, although the difference was not significant.

An overview of seasonal affective disorder and its treatment options

Seasonal affective disorder (SAD) is defined as a history of major depressive episodes that recur regularly at a particular time of year. Depending on the diagnostic instruments and criteria available, the reported prevalence (1%-10%) varies. Neurotransmitter abnormalities have been implicated in the pathophysiology, but they do not necessarily explain the seasonal pattern or the known chronobiological abnormalities in SAD compared with nonseasonal depression. Circadian rhythm abnormalies have been hypothesized to account for these aspects of SAD, and they provide a rationale for the therapeutic use of light therapy. Family history, twin, and molecular genetics studies suggest that hereditary factors are also involved. Light therapy and antidepressant medication are effective treatment options, with limited evidence for the efficacy of psychotherapy. Some studies demonstrate that narrow-band short wavelength "blue" light, naturalistic dawn simulation, and high-density negative air ionization are effective. Patients should be informed of the benefits of diet and exercise. Light therapy should be clinically monitored in the same manner, as it is done for other antidepressant treatments.

Exploring lag and duration effect of sunshine in triggering suicide

BACKGROUND

Sunshine is considered to have a beneficial impact on mood. Interestingly, it has been consistently found that the incidence of suicide reaches a peak during early summer.

METHODS

In order to explore the pattern of sunshine and suicide risk in a time frame of up to nine days and investigate possible lag and duration parameters of sunshine in the triggering of suicide, Greek daily suicide and solar radiance data were analyzed for a 10-year period using logistic regression models.

RESULTS

The solar radiance during the day before the suicide event was significantly associated with an increased suicide risk (OR=1.020 per MW/m2). The average solar radiance during the four previous days was also significantly associated with an increased suicide risk (OR=1.031 per MW/m2). Differences among genders include the longer sunshine exposure needed in males to trigger suicide, compared to females and a lag period of three to four days that was found to lapse in females till the suicide. The increase in suicide risk in June compared to December, attributable to the daily sunshine effect, varies from 52% to 88%, thus explaining the already known suicide monthly seasonality.

LIMITATIONS

No individual data on solar radiance exposure, mental disorders, alcohol consumption or suicide method were available.

CONCLUSION

The effect of sunshine in the triggering of suicide may be mediated through a mechanism with a specific lag and duration effect, during the nine days preceding suicide. We hypothesize that sunshine acts as a natural antidepressant which first improves motivation, then only later improves mood, thereby creating a potential short-term increased risk of suicide initially upon its application.

Light therapy for seasonal and nonseasonal depression: efficacy, protocol, safety, and side effects

Bright light therapy for seasonal affective disorder (SAD) has been investigated and applied for over 20 years. Physicians and clinicians are increasingly confident that bright light therapy is a potent, specifically active, nonpharmaceutical treatment modality. Indeed, the domain of light treatment is moving beyond SAD, to nonseasonal depression (unipolar and bipolar), seasonal flare-ups of bulimia nervosa, circadian sleep phase disorders, and more. Light therapy is simple to deliver to outpatients and inpatients alike, although the optimum dosing of light and treatment time of day requires individual adjustment. The side-effect profile is favorable in comparison with medications, although the clinician must remain vigilant about emergent hypomania and autonomic hyperactivation, especially during the first few days of treatment. Importantly, light therapy provides a compatible adjunct to antidepressant medication, which can result in accelerated improvement and fewer residual symptoms.

Somatic treatment for depressive illnesses in children and adolescents

Numerous somatic interventions have been studied as potential treatments of depressive disorders in children and adolescents. These include antidepressant medications, light therapy, electro-convulsive therapy, and alternative therapies. The available evidence suggests that several somatic interventions hold promise as potentially safe and effective treatments for depressed youths; however, there is still much to be learned about these interventions. This article reviews what is known and what needs to be learned about the somatic treatment of pediatric depression.

The effect of bright light exposure on pupillary fluctuations in healthy subjects

BACKGROUND

Light therapy is thought to be the first choice treatment of winter depression. However, its way of action is poorly understood. In order to find a solid effect of bright artificial light, we studied its possible alerting action through the spontaneous fluctuations of the pupil, considered to be an objective measurement of vigilance.

METHODS

Pupillary fluctuations of 10 healthy subjects (mean age: 22+/-1 S.D. years) were measured for 60 s before and 15 min after 0.5 h, 10000-lux light exposure. The cumulative change in pupil size, characterised by the pupillary unrest index (PUI) decreased at each subject, and this decrease was in average 35+/-4.4% S.E.M. The average pupillary diameters were unchanged (101+/-2.2% S.E.M.). This analysis revealed that the slow components of the pupillary fluctuations also decreased considerably.

LIMITATIONS

There was no dim light or other placebo control of the light treatment.

CONCLUSIONS

Bright light exposure significantly influenced the pupillary fluctuations. We suppose that bright light exposure increases the level of alertness, and this could be a possible way by which bright artificial light exerts a beneficial effect also in affective disorders.

An epidemiological study on gender differences in self-reported seasonal changes in mood and behaviour in a general population of northern Sweden

Gender differences have been reported regarding symptoms, prevalence and heritability of seasonal affective disorders (SAD). We focus on gender aspects in this study of self-reported seasonal changes in mood and behaviour in a general population. The Seasonal Pattern Assessment Questionnaire (SPAQ) was completed by 2620 adults (55.6% women) aged 35-85 years, enrolled in the Betula prospective random cohort study of Umeå, Sweden. October to February turned out to be suitable winter months. SAD was found in 2.2% and sub-syndromal SAD (S-SAD) in 5.7%. Women had about 1.5 times higher prevalences than men, and seasonality problems decreased with age in both genders. Preference for eating least was distributed with a peak in summer, whereas preference for eating most had a major peak in winter (winter eaters) and a minor peak in summer (summer eaters). Significantly more of winter eaters in women, and significantly more of summer eaters in men, felt worst in winter. Seasonal change in weight was considered significantly as a problem by women but not by men. Winter behaviour of sleeping most was considered significantly as a problem by men but not by women. Women reacted significantly to temperature-related changes (negatively to cold/short days and positively to hot/long days), whereas men reacted significantly to sunshine-related changes (negatively to cloudy days and positively to sunny days). Subtle gender differences may thus underlie the pathophysiology of seasonal problems. Studies of an eventual efficacy of treating SAD women with raised ambient temperature, and gender-specific comparisons with other therapies, would be of interest.

Light treatment of mood disorders

In 1981, seven patients with nonseasonal depression were treated with bright white light in 1982, bright artificial light was used to treat a manic-depressive patient with a seasonal mood cycle. In the last 20 years, a plethora of studies have further defined the depressive populations, who are responsive to light treatment; the optimal timing, intensity, spectral frequency, and duration of treatment; its comparison with other pharmacological interventions; predictors of response; side-effect profiles; viable placebo-control conditions; alternative devices and forms of administration; potential mechanisms and anatomical pathways mediating light's physiological effects; and its application to other disorders and subsyndromaI states. These studies have been conducted across multiple countries with surprisingly consistent results. Further work is needed, as highlighted in this review, to clarify the specific mechanism of action in subtypes of depressive disorders and differential age and gender effects. Although the majority of work in this area is relatively new, it behooves the reader to remember that Solomon, almost 3000 years ago, wrote in Ecclesiastes: "Truly the light is sweet and a pleasant thing it is for the eyes to behold the sun" (11:7).

Modulation by sudden darkness of apomorphine-induced behavioral responses

Sudden darkness increases motor activity and decreases anxiety. In the present study, we focused on the role of dopaminergic mechanisms involved in the effects of sudden darkness. The influence of sudden darkness on the behavioral effects of low (0.05 and 0.1 mg/kg) and high (0.25, 0.45 and 0.6 mg/kg) doses of apomorphine (APO) was tested. We assayed the effects of low APO doses on yawning-penile erection syndrome (YES; 0.05 and 0.1 mg/kg) and on motor activity (0.05 mg/kg), and the effects of high APO doses on motor activity (0.25 mg/kg) and stereotyped behavior (0.45 mg/kg and 0.6 mg/kg). Spontaneous total and genital grooming of male and female rats were also recorded. Sudden darkness modified some spontaneous behaviors and also modulated several APO-induced behavioral effects. It increased spontaneous total grooming and genital grooming in male rats but had no effect on these parameters in female rats. These results show sexual dimorphism for total and genital grooming in both control and sudden darkness conditions. APO was able to induce YES in a dose-dependent manner. Sudden darkness decreased yawning elicited by both 0.05 and 0.1 mg/kg of the drug. No other parameter of YES was modified. In the open-field test, sudden darkness increased total locomotion and rearing and decreased immobility duration. APO at a dose of 0.05 mg/kg had the opposite effect on these parameters under light conditions; none of them were modified by sudden darkness. Animals treated with APO at 0.25 mg/kg, a dose that augmented total locomotion and rearing and diminished immobility duration, were clearly divided into two groups according to their responses, i.e., hypo- and hyper-responsive rats. Sudden darkness improved total locomotion and rearing, reduced immobility duration and total grooming in the hyporesponsive group, and showed no effects on the hyper-responsive group. Sudden darkness caused no modifications of stereotyped behavior. These results may be due to a sudden darkness-induced physiological release of dopamine that diminishes pre-synaptic responses to APO and increases low-intensity post-synaptic responses such as motor activity without modifying high-intensity post-synaptic responses such as stereotyped behavior.

Effectiveness of complementary and self-help treatments for depression

OBJECTIVES

To review the evidence for the effectiveness of complementary and self-help treatments for depression.

DATA SOURCES

Systematic literature search using PubMed, PsycLit, the Cochrane Library and previous review papers.

DATA SYNTHESIS

Thirty-seven treatments were identified and grouped under the categories of medicines, physical treatments, lifestyle, and dietary changes. We give a description of each treatment, the rationale behind the treatment, a review of studies on effectiveness, and the level of evidence for the effectiveness studies.

RESULTS

The treatments with the best evidence of effectiveness are St John's wort, exercise, bibliotherapy involving cognitive behaviour therapy and light therapy (for winter depression). There is some limited evidence to support the effectiveness of acupuncture, light therapy (for non-seasonal depression), massage therapy, negative air ionisation (for winter depression), relaxation therapy, S-adenosylmethionine, folate and yoga breathing exercises.

CONCLUSION

Although none of the treatments reviewed is as well supported by evidence as standard treatments such as antidepressants and cognitive behaviour therapy, many warrant further research.

Seasonal affective disorder among general practice attenders

In this issue, Eagles et al report that people suffering from seasonal affective disorder (SAD) are heavy users of primary health care services (Eagles et al, 2002, this issue). Nearly 10% of patients attending practices in Aberdeen screened positive for SAD using the Seasonal Pattern Assessment Questionnaire (SPAQ; Rosenthal et al, 1987), among whom around half of those attending for interview fulfilled DSM–IV (American Psychiatric Association, 1994) criteria for recurrent major depression with seasonal pattern. The patients with SAD had consulted significantly more frequently over a 5-year period, with a variety of symptoms both related and unrelated to SAD, and had received significantly more prescriptions, investigations and referrals than patients found not to fulfil the criteria for SAD.

Use of health care services in seasonal affective disorder

BACKGROUND

Little is known about the presentation and management of seasonal affective disorder (SAD) in primary care.

AIMS

To determine the use of health care services by people suffering from SAD.

METHOD

Following a screening of patients consulting in primary care, 123 were identified as suffering from SAD. Each was age- and gender-matched with two primary care consulters with minimal seasonal morbidity, yielding 246 non-seasonal controls. From primary care records, health care usage over a 5-year period was established.

RESULTS

Patients with SAD consulted in primary care significantly more often than controls and presented with a wider variety of symptoms. They received more prescriptions, underwent more investigations and had more referrals to secondary care.

CONCLUSIONS

Patients with SAD are heavy users of health care services. This may reflect the condition itself, its comorbidity or factors related to the personality or help-seeking behaviour of sufferers.