Seasonal Affective Disorder and AS
People with ankylosing spondylitis (AS) already face depression risks that result from chronic pain, physical limitations, and reduced quality of life.1 However, this time of year also brings another depressing possibility: seasonal affective disorder (SAD). Also known as the winter blues, it affects those living farthest from the equator. It’s caused by shorter periods of fading daylight, which can disrupt circadian rhythms.
People with AS might struggle to differentiate SAD from ordinary depression. What does SAD look like? How do chronic pain and sleep problems factor into SAD? And how might people with AS deal with SAD?
SAD is more than depressed
As the name implies, changing natural light triggers SAD at the end of summer. Fall’s daylight saving time makes this change even more apparent. By winter solstice (the shortest day and longest night of the year), some people find themselves in a deep, dark circadian funk.
Circadian rhythms, from the inside out
Light exposure provides critical signals to the body and brain for maintaining circadian rhythms. These rhythms regulate major body processes, including sleep-wake patterns managed by the sleep hormone, melatonin.
Daylight saw through the eyes cues the brain to keep melatonin levels higher in the bloodstream. As the light dims in the afternoon, the brain releases more melatonin. As light brightens in the morning, the brain produces less.
However, shorter days mean melatonin release comes earlier and then is shut off later. This can shift circadian rhythms in a way that disrupts a normal 9-to-5 workday or 8-hour night of sleep. This can lead to all sorts of issues with your sleep cycles and mental health.
People living in rainy, overcast northern climates are more likely to experience SAD than those enjoying daily sunshine. Also, people spending time outside will feel less impact than those spending their days indoors.
Everyone’s different, of course. Some people with SAD will feel less energized, while others will feel a range of effects: insomnia, appetite changes, mood swings, daytime fatigue, and more.
What SAD looks like
Common signs and symptoms of SAD include2:
- Daily feelings of depression, hopelessness, worthlessness
- Less interest in favorite activities
- Low energy
- Sleep problems (insomnia, daytime sleepiness, fragmented sleep)
- Changes in weight and hunger feelings
- Feelings of agitation, irritability
- Less attention, focus, concentration
- Feeling suicidal
The depression-pain-sleep triangle
Let’s face it; people with AS already feel some of these. Chronic pain is known to lead to depression, feeling suicidal, sleep problems, and withdrawal from life due to fatigue.3 Research published last summer in Psychiatric Investigation confirms that people with AS face higher depression risks in general.4,5
This large study found that “the pooled prevalence of depression in AS patients is 35% and higher than other chronic medical illnesses such as asthma (27%), chronic obstructive lung disease (24.6%), lupus (24%) and rheumatoid arthritis (15%).” However, two other SAD connections—-pain and sleep=—might also suggest the causes of depressive symptoms beyond AS.
The chronic pain connection
In an interview with Practical Pain Management, Dr. Shanthi Mogali, director of psychiatry at Mountainside Treatment Center, suggested that those living with chronic pain keep SAD “on the radar” at this time of year.6 She referenced two studies showing that people in chronic pain experience seasonal variations in pain intensity, with psychological consequences.6
Pain: The enemy of sleep
Meanwhile, poor sleep and pain are mutual bedfellows. AS research in 20187 points to sleep problems as a leading cause of poor mood, greater fatigue, and increased back pain and stiffness for people with AS. The result? Insomnia and poor sleep.
Other sleep disorders linked to SAD might create problems for people with AS, as well.
Delayed sleep phase syndrome (DSPS) is a circadian rhythm sleep disorder in which one’s sleep rhythms shift later8, resulting in “night owl” sleep-wake patterns. Unfortunately, these people may still need to rise at the same time every day, leading to sleep debt.
Sleep debt is shorthand for sleep deprivation over a long period of time. Without recovery of that lost sleep, chronic conditions like AS are bound to get worse.
What you can do
If you suspect your depression might be seasonal, ask your doctor for help.
Meanwhile, simple relief for SAD can be found by practicing good sleep hygiene and helping your circadian rhythms. For instance, seek out exposure to natural light during the early part of the day.
Other than back pain and fatigue, what is the most common symptom that AS patients experience?