A woman is in silhouette, looking out a window to a wintery, dark scene of bare trees and little sunlight.

When Your Alzheimer’s Loved One Is SAD: Dealing with Seasonal Affective Disorder

It’s no secret that Alzheimer’s disease (AD) and other conditions of dementia share unfortunate connections to depression. As many as 68 percent of people with dementia also experience depression. It’s also considered a risk factor and a prodrome (an early sign) for AD.1

This time of year, it’s good to be alert to changes in mood, energy levels, and poor sleep if a loved one with AD suddenly seems more depressed than usual.

You can’t blame anyone for feeling a little off at the onset of dim skies and gloomy rain, but a little sadness over dark weather isn’t reason enough for depression to take hold.

We’re all prone to dips in mood during autumn and winter’s days of diminishing light. But people with AD or other types of dementia may be especially sensitive to something known as seasonal affective disorder (SAD).

What is seasonal affective disorder (SAD)?

SAD describes a kind of recurring depressive state that seems to follow a seasonal pattern. Most cases of SAD take place in the fall and winter, but cases of summer SAD also exist, in which more sunlight and longer days can prompt symptoms of depression.

This form of depression, sometimes also called 'cabin fever', 'winter blues', or 'seasonal depression', has a circadian element.

Our circadian rhythms, which help keep our body functioning at optimal capacity, rely on time cues like exposure to natural light to stay balanced.

Unfortunately, the farther away we live from the equator, the more likely we’re going to feel the effects of lower light during the fall and winter. When our circadian rhythms are disrupted in this way, it can lead to all kinds of physical and mental health challenges.

What’s worse, people with AD and their caregivers may miss this connection between changing seasons and their changing mood. How, then, do you know when someone with AD also has SAD? Many of its symptoms overlap with AD.

Symptoms of SAD include:

  • Unexplained weight gain and changes in appetite (either a bigger appetite or appetite loss)
  • Depressive behaviors such as suicidal ideation and feelings of helplessness
  • Feeling physically and emotionally lethargic
  • Less motivation for or avoidance of social or self-care activities normally anticipated and enjoyed
  • Problems with memory and concentration

If you suspect your loved one has SAD

It’s always good to mention any changes in mood or energy levels to the medical provider in charge of a loved one’s care.

They may use helpful screening tools to determine if these dips are an expression of their AD or if they’re prompted instead by circadian disruptions in response to changing seasons.

Sleep: The missing link?

Watch for disrupted sleep, at this time of year especially, as it can be linked to both AD and SAD.

Poor sleep is a big problem for people with AD in general. But not everything that a person with AD experiences can be blamed on their condition. Poor sleep can also be caused by an underlying and unidentified sleep disorder.

Sleep disorders may wreak havoc at night for people with various dementias.2 The most common sleep issues include:

  • Obstructive sleep apnea (OSA) and central apnea (CA)
  • Circadian rhythm sleep disorders—SAD falls into this category—and insomnia (both linked to sundowning)
  • REM sleep behavior disorder (RBD), in which one acts out dream content
  • Movement disorders of sleep: Restless legs syndrome (RLS) and periodic limb movement disorder (PLMD)

If poor sleep happens most nights for weeks at a time, talk to your healthcare provider. They may ask questions about sleep habits and patterns. They may also screen for hidden sleep disorders.

Your doctor can suggest therapies and sleep hygiene “best practices” that might help with sleeplessness or fitful sleep so common with AD.

It’s worth it to identify and treat these problems if they’re present. Sometimes, treatment of other forms of depression and/or sleep disorders can also provide symptom relief for both SAD and AD.

Things you can do to push away the SAD

  • Try to plan fun seasonal activities. In the fall, activities can include pumpkin carving, country drives to enjoy the changing leaves, outdoor bonfires, and football tailgating.
  • Don’t skimp on physical activity, including strolls, hikes, or bicycle rides on clear days. These activities can be especially pleasant if the weather isn’t too cool or wet.
  • Make sure interior lighting is adequate to keep daytime mood elevated and even.
  • Go outside in the morning and early afternoon to enjoy exposure to natural sunlight, which enhances vitamin D production and naturally boosts mood.
  • Get the okay from your doctor to invest in a “happy light” to use in the morning to boost both circadian rhythms and mood (20 minutes should be sufficient).
  • Talk to your AD healthcare provider about helpful therapies such as antidepressant medications, light therapy, vitamin D supplementation, and cognitive behavioral therapy.

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This article represents the opinions, thoughts, and experiences of the author; none of this content has been paid for by any advertiser. The AlzheimersDisease.net team does not recommend or endorse any products or treatments discussed herein. Learn more about how we maintain editorial integrity here.

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