Here in the UK the days are noticeably shorter, and this time of year will herald for some the advent of low mood or sometimes full-blown depression known as ‘seasonal affective disorder’ (SAD). Anecdotally, I’ve noticed that many people dislike the winter because they can struggle to get up in the mornings. A lot of people say they hate having to get up ‘in the dark’. A recent study suggests that this phenomenon and SAD might have a common root.
This study in question, published in the Journal of Affective Disorders, assessed individuals who exhibited evidence of what is known as ‘delayed phase sleep phenomenon’ (DPSP). This condition is characterised by individuals have difficulty falling asleep at night, and having difficult rising in the morning too. I have written about DPSP previously here.
The researchers looked for the evidence of SAD in individuals with DPSP, and compared this with ‘controls’ (those without DPSP). They found that those with DPSP were more than three times more likely to have SAD.
Those with DPSP were also found to be more likely to experience ‘seasonality’ in things like appetite, fatigue and body weight. In other words, those with DPSP were prone to experience things like increased fatigue, enhanced appetite and weight gain in the winter – something that is common with individuals suffering from SAD.
The authors of this study conclude that SAD and DPSP are often to be found together in the same person, and this supports the idea that they may share a common ‘pathophysiological mechanism’.
In the blog post I link to above, I write about two approaches that might be effective in helping those with DPSP. One of these is light therapy, and the other is treatment with the sleep-related hormone melatonin. Light therapy, by the way, has been shown to have potential in the treatment of SAD. I’m not aware of any research that has found melatonin helps individuals with SAD, but I would not be at all surprised if such evidence comes to light. For more about the natural treatment of SAD, see here.
1. Lee HJ, et al. Delayed sleep phase syndrome is related to seasonal affective disorder. J Affect Disord. 2011;133(3):573-9.