Understanding Major Depressive Disorder with Seasonal Pattern

Winter can be tough. The cold weather, slippery roads, and shorter days can leave people feeling drained and isolated. While the season can be a time of joy, family and friend connection, and cozy moments, for some it can also bring a dip in mood and a sense of heaviness. If you find yourself struggling, or notice that someone you care about may be struggling, it’s important to know you are not alone, and there is support available. 

Seasonal changes may have impact beyond “typical winter blues”.  This experience may be “Major Depressive Disorder with Seasonal Pattern”, commonly referred to as SAD, or Seasonal Affective Disorder (Levitan, 2022, Melrose, 2015, Fonte & Coutinho, 2021). 

So What is MDD with Seasonal Pattern?

The DSM-5 (APA, 2013) classifies MDD with Seasonal Pattern as a subtype of depression, and notes that an individual must have experienced two episodes of MDD in a two year period and that the episodes must have a relationship to the time of year in order to fit the criteria for this particular diagnosis. Remission must also occur with a seasonal pattern (APA, 2013). For some individuals, they experience a spontaneous improvement in symptoms when spring and summer occur, but for some individuals more intervention is required. Although most commonly thought of as impacting people in the winter, there are individuals who are impacted in the warmer months and feel better in the winter months (Melrose, 2015, Fonte & Coutinho, 2021).

Symptoms of MDD with Seasonal Pattern

Symptoms can range from mild to severe, and might include low energy, low mood, difficulty concentrating, increased sleep, isolation from social situations, and more (Melrose, 2015; Levitan, 2022; Fonte & Coutimho, 2021). For some, these symptoms may feel like more of a minor inconvenience, but for others the experience can be debilitating. It is important to recognize that this is a significant struggle for some individuals and should be taken seriously. 

Who is most at risk?

It is estimated that about two percent of the Canadian population experiences MDD with Seasonal Pattern (Melrose, 2015). This may sound like a low number, but in reality it means a little less than million Canadian's are impacted.  Generally, the onset of experiencing MDD with Seasonal Pattern is between the ages of 18-34, and women are higher risk than men, approximately four times more likely to experience Major Depressive Disorder with Seasonal Pattern. It has also been suggested that shift workers and individuals who spend less time in the winter sun are at a higher risk (Melrose, 2015).

What can you do if you or someone you love may be experience MDD with Seasonal Pattern?

So what should you do if you, or someone you love may be experiencing MDD with Seasonal Pattern? Start by reaching out to your health care provider who can assess your symptoms and determine if you are experiencing MDD with Seasonal Pattern, or if something else may be at play. 

Therapy can helpful initial step as well. Find a therapist who is able to support you in managing the emotional and psychological impacts of depression, provide strategies to manage symptoms and tips to improve overall functioning.

Light Therapy: A Potential Treatment

There is also research suggesting that light therapy may be helpful for individuals who experience Major Depressive Disorder with Seasonal Pattern (Melrose, 2015). The American Psychiatric Association (2024) notes that light therapy can be helpful in treating MDD with Seasonal Pattern, and that treatment usually lasts the duration of winter and for those who have a history of MDD with Seasonal Pattern, treatment may begin in early fall.

To be effective, the light used for light therapy needs to be fluorescent, with a diffusion screen and an intensity of 10,000 lux. Standard treatment is generally 30 minutes per day in the morning, but this is something you should consult your care team about. Like most things, there are also potential risks to light therapy, including eye injury and headaches. (Mayo Clinic, 2022)

Sources

American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: Author.

American Psychiatric Association (2024): Seasonal Affective Disorder (SAD). Retrieved from:https://www.psychiatry.org/patients-families/seasonal-affective-disorder

Campbell, P. D., Miller, A. M. & Woesner, M.E. (2017). Bright light therapy: Seasonal Affective Disorder and Beyond. Einstein J Biol Med. 

Centre for Disease Control and Prevention (2022). Retrieved from: https://www.cdc.gov/diabetes/managing/eat-well/food-labels.html#:~:text=The%20label%20breaks%20down%20the,information%20can%20differ%20a%20lot.

Fonte, A., Coutinho, B. (2021). Seasonal sensitivity and psychiatric morbidity: A study about seasonal affective disorder. BMC Psychiatry, 21 (317). https://doi.org/10.1186/s12888-021-03313-z

Levitan, R. D. (2022). The chronobiology and neurobiology of winter seasonal affective disorder. Dialogues in Clinical Neuroscience, 9(3). https://doi.org/10.31887/dcns.2007.9.3/rlevitan

Mayo Clinic (2022). Seasonal affective disorder treatment: Choosing a light box. Retrieved from: https://www.mayoclinic.org/diseases-conditions/seasonal-affective-disorder/in-depth/seasonal-affective-disorder-treatment/art-20048298#:~:text=Generally%2C%20the%20light%20box%20should,little%20UV%20light%20as%20possible

Melrose, S. (2015). Seasonal Affective Disorder: An overview of assessment and treatment approaches. Depression Research and Treatment. https://doi.org/10.1155/2015/178564

O’Mahony, L., Stepien, M., Gibney, M. J., Nugent, A. P., & Brennan, L. (2011). The potential role of vitamin D enhanced foods in improving vitamin D status. Nutrients, 3(12), 1023-1041. https://doi.org/10.3390/nu3121023