Many people experience seasonal depression yearly during the winter months, and the prolonged pandemic could very well add stress factors that could worsen their depression.

Nicholas Allan, an assistant professor of clinical psychology at Ohio University, said that depression is diagnosed using the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) or international classification systems. If someone shows five to nine symptoms such as loss of interest or pleasure or lack of enjoyment, they are diagnosed with depression.

Allan said there are also some physical symptoms, such as insomnia, loss of appetite or overeating and difficulty concentrating. He also said around 15% of the U.S. population could experience depression in their lifetime, and 7% are likely to meet diagnostic thresholds for depression yearly.

“While those numbers are high, there are people who may have symptoms of depression below diagnostic thresholds but are still affected and distracted,” Allan said.

A contributing factor of seasonal depression known in psychology as Seasonal Affective Disorder (SAD), is colder weather that drives people indoors, where they experience loneliness and social isolation. A combination of environmental factors such as staying indoors and lacking Vitamin D is likely to cause depression, Allan said.

“One of the things that's interesting about Seasonal Affective Disorder is while it’s found often during the winter, there are cases where people have it in the summer,” Allan said.

Allan said about 5% of the U.S. population is affected by SAD per year, and 10-20% have mild symptoms not needed for diagnosis. SAD is four times more common in women than men. Allan said women are one-and-a-half to two times more likely to experience depression due to a combination of biological and large-scale environmental impacts.

On top of SAD, the world is eight months into a pandemic, which can lead to pandemic depression. Social isolation, stress, anxiety and uncertainty are all risk factors people have been facing for several months during the COVID-19 pandemic.

“Think about all the anxiety and uncertainty people have been feeling for the longest time,” Allan said. “With all these risk factors, people start to withdraw.”

The diathesis-stress model presumes a person’s livelihood of life stressors based on vulnerability and environmental factors. Allan thinks of the diathesis-stress model as a cup filled with different amounts of liquid for different people. The liquid is higher for some people, which represents their stressors. The more liquid one has in the cup, the more stressors they have. With all the stressors of the pandemic, people’s “cups” are overflowing.

Kevin David, a graduate student studying psychology, said the symptoms of depression itself are often recurring problems for those who suffer from the disorder. Individuals typically experience episodes, which are symptoms returning after being absent for a period of at least two months. 

“Seasonal Affective Disorder is how older versions of the Diagnostic and Statistical Manual for Mental Disorders (DSM) referred to what is now known as Major Depressive Disorder (MDD), Recurrent, With Seasonal Pattern,” David said in an email.

David said the stress of a global pandemic, coupled with isolation brought about by quarantine and financial security, sounds like a massive spike in depression based on the diathesis-stress model.

“I would be personally shocked if the pandemic did not cause an increase in depression, though I don't know of any studies with strong enough findings at this point that I could say for certain,” David said in an email.

David said social support can help buffer against depressive symptoms, and social isolation is removing that buffer. He added that individuals experiencing a lack of joy in things they used to enjoy, low energy, lack of motivation and especially thoughts of harming themselves, should know they are not alone, and at the same time, having those feelings is in no way a moral failing.

“If someone happens to be in the state of Ohio at this time during the pandemic, many therapy services are being administered remotely, bringing greater access to individuals who otherwise would have had lengthy commutes to seek professional help,” David said in an email. “Now you can reach out to clinics such as the one I currently work for (the Ohio University Psychology and Social Work Clinic) and start talking to somebody who wants to help you through this.”

Zach Williams, a sophomore studying integrated media, said he believes seasonal depression comes around in the winter months because people stay inside when it gets colder and miss out on social opportunities.

“Isolation also contributes to the pandemic and how that causes depression,” Williams said. “I think people are just tired because the pandemic has lasted so long. When you combine the stress of COVID-19 with having seasonal depression and being in your own head all the time, that’s not going to mix well.”