Written by Jasmine Lobo, Edited by Olivia McCollum, Edited by Courtney Coleman
Introduction
Seasonal affective disorder (SAD) is characterized by symptoms of depression that follow annual patterns, with symptoms arising and improving as the seasons change.1 SAD is typically associated with the onset of symptoms during the transition from summer to fall and winter; however, SAD has also been shown to follow an opposite pattern, with depressive symptoms worsening with the warmer summer months and improving in fall and winter.2 SAD is believed to be frequently unreported and underdiagnosed, but it could affect up to 4-15% of the general population in North America and Europe.3,4
Symptoms
People with SAD may experience significant changes in mood and behavior, often exhibiting symptoms associated with depression; however, symptoms may vary by individual depending on their specific subtype of SAD.2
Risk Factors
The exact cause of SAD is unknown, especially for summer-pattern SAD because it is less common, and research into the condition is lacking.2 Recent studies have shown that winter-pattern SAD is associated with decreased serotonin levels and vitamin D deficiency.2,3 Reduced sunlight levels during the winter affect vitamin D production and the maintenance of serotonin levels, a hormone that regulates mood.2,3 Additionally, altered levels of melatonin, a hormone that maintains the sleep–wake cycle, are also associated with SAD. While overproduction of melatonin is related to oversleeping in people with winter-pattern SAD, low levels of melatonin are associated with poor sleep quality that worsens depressive symptoms in people with summer-pattern SAD.2 Furthermore, there is a link between certain variations of genes that control our body’s regulatory clock and SAD.4
SAD is more prevalent in those who live in northern latitudes due to a link between winter pattern SAD and a shortage of daylight.5 In addition, SAD is more prevalent among younger people and more common in women compared to men.4,5 Additional risk factors for SAD include having a family history of SAD or depression, as well as having major depression or bipolar disorder.
Treatment
Psychotherapy, or counseling, is a common treatment option for people with SAD. Cognitive behavioral therapy for SAD (CBT-SAD) consists of group sessions in which people with SAD learn to replace negative thoughts associated with the season and participate in outdoor activities. These therapies help individuals deal with a loss of interest in social experiences they may experience as a result of isolating behaviors associated with SAD. Antidepressant medication may also help people with SAD to manage their depressive symptoms.2 For winter-pattern SAD, there are standardized treatment approaches that are widely accepted for symptom management. Light therapy may help winter-pattern SAD by using daily artificial light exposure for about 30-45 minutes which can help mitigate the negative symptoms of decreased light exposure during the winter months. In addition, vitamin D supplements may also improve vitamin D deficiency.2
References
1. Seasonal affective disorder. Johns Hopkins Medicine. Accessed March 21, 2024. https://www.hopkinsmedicine.org/health/conditions-and-diseases/seasonal-affective-disorder#:~:text=Seasonal%20affective%20disorder%2C%20or%20SAD,antidepressants%20can%20help%20treat%20SAD
2. Seasonal affective disorder. National Institute of Mental Health (NIMH). Accessed March 21, 2024. https://www.nimh.nih.gov/health/publications/seasonal-affective-disorder
3. Melrose S. Seasonal Affective Disorder: An Overview of assessment and Treatment Approaches. Depression Research and Treatment (Print). 2015;2015. doi:10.1155/2015/178564
4. Dang T, Russel W A, Saad T, Dhawka L, Ay A, Ingram K K. Risk for Seasonal Affective Disorder (SAD) Linked to Circadian Clock Gene Variants. Biology (Basel). 2023;12(12). doi:10.3390/biology12121532
5. Meesters Y, Gordijn MCM. Seasonal affective disorder, winter type: current insights and treatment options. Psychology Research and Behavior Management. 2016;Volume 9:317-327. doi:10.2147/prbm.s114906
6. Seasonal affective disorder (SAD) - Symptoms & causes - Mayo Clinic. Mayo Clinic. Published December 14, 2021. Accessed March 21, 2024. https://www.mayoclinic.org/diseases-conditions/seasonal-affective-disorder/symptoms-causes/syc-20364651
This post is not a substitute for professional advice. If you believe that you may be experiencing a medical emergency, please contact your primary care physician, or go to the nearest Emergency Room. Results from ongoing research is constantly evolving. This post contains information that was last updated on December 24, 2024.
Comments