Many people experience a change in mood as the seasons turn, especially as the days start to shorten and the cold weather draws in. For many people, the winter blues are a familiar feeling but do pass or at least fluctuate. For some people, the low mood linked to winter can be more persistent, debilitating even, and interfere with getting on with everyday life. In cases like this, a diagnosis of Seasonal Affective Disorder (ironically acronymed as SAD) might help to shed light on things.
What is SAD?
First coined two decades ago in the USA, researchers found they needed to explain the winter-triggered depressive symptoms that are estimated to affect over 6% of Americans. Rates in the UK seem to be around 8% for acute symptoms but in a recent survey, over 50% of adults polled claimed that their mood worsened over the winter months. Classic indicators for SAD include a persistent low mood, increased irritability, loss of pleasure and interest in things, feelings of despair and low worth, sluggishness and fatigue, sleeping more and finding it hard to get up, and craving carbohydrates and gaining weight.
Light and hormones
The prevailing explanation for these symptoms has been the impact that a reduction in natural light has on a part of the brain called the hypothalamus. It is responsible for melatonin (the sleepy hormone), serotonin (the hormone regulating mood, appetite and sleep), and our circadian rhythm (or body clock). When these three centres get out of whack, it’s no wonder that things start going awry.
As such, light therapy as been the main recommended treatment for SAD, with over 50% of patients reporting improvements when dosed with 10,000 lux diffused white fluorescent light taken early in the morning. Doses often need to be personally titrated and remission rates rise to 80% when the dose is tailored to a person’s unique sleep-wake cycle.
When light and hormones meet depression: a bio-psycho-social cure
In addition to this, lifestyle measures such as regular exercise, as much exposure to natural light as possible and stress management also seem to be helpful – partly because they address the reduction in activity and withdrawal from things that hallmark depression. In this vein, new research indicates that light therapy and psychological interventions bring the greatest improvement to SAD sufferers.
This is because SAD is both a biological and psychological phenomenon. The lack of light falls onto fertile ground as it were and studies suggest that people most affected by SAD tend to be people who withdraw when faced with aversive events (quite logically one might add, albeit counter-productive to mood enhancement) and who ruminate about negative events. Recent studies have shown that CBT interventions that help to reframe negative beliefs about winter and assist with introducing greater behavioural activation in the darkest months – particularly those that bring enjoyment and pleasure – are associated with the longest-lasting reduction in SAD symptoms. Why do you think the Danes have hygge or the apres-ski scene is so appealing?
For people who are already struggling with things, winter can feel like a welcome retreat from the assault of light and life that summer brings. (In fact some people get SAD in summer!) Nonetheless, retreating is a key maintaining factor in depression as it decreases our ability to feel a sense of achievement, closeness with others or enjoyment. Deprivation of pleasure and isolation are two of the biggest cronies of depression.
If you recognise yourself in this description it might be that treating both the SAD and any underlying difficulties with a course of talking therapy could prevent these from persisting and worsening over time. Please do feel free to contact us at The Practice at 322 for more on how we might be able to help.