Why Evenings Are the Hardest: Understanding Sundowning in Dementia

Reserve and Fatigue: Understanding and Caring for "Sundowning" in Dementia

Despite several years of struggle with her illness, and notwithstanding my geriatrician's familiarity with the many twists and turns of cognitive impairment, I never expected my mom to experience one of dementia's most common features. A former law professor and avid consumer of political, sports, and pop-culture news, she always—always—had something to say. Whether providing us with the latest on quarterback Trevor Lawrence's hair (a perennial fascination) or the did you hear about? questions worthy variably of an op-ed page, of 24-hour TV news or of TMZ, she was rarely quiet, and never disengaged from her family's goings-on. This remained true even as she, and we, began to confront her vascular dementia, which would ultimately worsen in part due to a condition called normal pressure hydrocephalus. And so when my dad told me that she was experiencing evenings where she just "stared off into space," I initially thought that something else had to be wrong. Could her blood pressure medication be too strong? Was her diabetes management off-kilter? Could she be having small seizures? My dad and I worked through these questions on the phone for a few weeks, until I was finally able to make the 8-hour trip to see her.

What Is Sundowning—and Why Is It So Hard to Define?

Scientifically, we don't exactly know what causes sundowning, or "sundown syndrome," as some call it. The gaps in our understanding are striking when we consider how prevalent it is for those living with dementia. Although research varies, it likely affects somewhere between one-fourth to one-half of us at some point in our dementia journey. Some studies, like this one, have in fact suggested that sundowning in those with Alzheimer's disease may be due to the disease's disruption of normal circadian rhythms, but this doesn't seem to explain all cases, including its prevalence in other forms of dementia (like my mom's). In the midst of uncertainty, and especially from a caregiver's perspective, it is most helpful for us to ask not how sundowning happens, but why.

Why Sundowning Happens: Cognitive Reserve and Fatigue

Scientifically, we don't exactly know what causes sundowning, or "sundown syndrome," as some call it. The gaps in our understanding are striking when we consider how prevalent it is for those living with dementia. Although research varies, it likely affects somewhere between one-fourth to one-half of us at some point in our dementia journey. Some studies, like this one, have in fact suggested that sundowning in those with Alzheimer's disease may be due to the disease's disruption of normal circadian rhythms, but this doesn't seem to explain all cases, including its prevalence in other forms of dementia (like my mom's). In the midst of uncertainty, and especially from a caregiver's perspective, it is most helpful for us to ask not how sundowning happens, but why.

There are two concepts in dementia care that illuminate our answer: cognitive reserve and cognitive fatigue. Cognitive reserve refers to our brain's overall strength, its ability to weather the storms of the day. No matter our age, and whether we are early birds or night owls, few (if any) of us can put forth full cognitive effort, hour after hour without rest and recuperation. In this way, cognitive reserve is analogous to physical reserve: even elite athletes need downtime. At baseline, all of us have different degrees of cognitive reserve (just like not all of us can have physical reserve like Roger Federer or Allyson Felix), and we all experience some decline in our reserve as we age. This is normal. But for those living with dementia, our age-appropriate levels of cognitive reserve begin to erode. Our capacity to "push back" against cognitive stressors weakens. For some, this weakening happens very gradually. It can be nearly imperceptible for years. But particularly in conditions like Alzheimer's disease, as well as in other forms of dementia, the weakening of our cognitive reserve can accelerate. For the person living with dementia, this makes navigating their world increasingly challenging. It can feel like running hurdles, all day.

Which brings us to cognitive fatigue. When our cognitive reserve diminishes, we grow tired much more easily and frequently. We trip on the hurdles, and, at some point, we may stop running for a rest. What's more, cognitive fatigue doesn't occur in isolation. Those living with dementia may also be simultaneously physically and emotionally weary at the same time as they are cognitively stretched. And so here is a caregiver-centered definition for sundowning: A complex state of fatigue, driven by decline in cognitive reserve as well as possibly also physical or emotional reserve. The fatigue is "complex" because it might not (as my mom's did) look like fatigue. Sundowning can result in hyperactive states: pacing, seemingly fretful confusion, and, as noted, psychological concerns like hallucinations or apparent paranoia. Here, it important to remember that potential sources of stress don't disappear when our loved ones with dementia need a rest. In fact, it is precisely during those moments that to them, the stressors may seem their largest and most insurmountable.

How to Care for Sundowning: Anticipate, Observe, Alleviate

So how best can we care for those with dementia when sundowning occurs? I recommend three practices: Anticipate, Observe, and Alleviate. Together, these three practices focus on trying to understand why our loved one is experiencing sundowning, and on addressing the sources of their increased confusion.

Anticipate: During the last year of her life, my mom's sundowning became much more frequent. She would begin to tire somewhere around seven or eight o'clock, though if she took extra naps during the daytime, sometimes nine o'clock. Although she mostly felt exhausted, occasionally she would also seem afraid. We learned to predict her discomfort: if she was finishing a particularly active day, we would try to ensure that she was in bed early, minimizing any potential stressors, before the sundowning would begin. Anticipation is about looking for patterns and rhythms in your loved one's day, and building routines around them.

Observe: This practice goes hand-in-hand with anticipation. We need not only to observe for patterns, but also to try to discern what the causes of sundowning might be. I use causes in the plural on purpose: more often than not, there are multiple stressors at hand. To merely improve lighting as the sun goes down may not be enough. If our loved one seems to be anxious, why might they be anxious? Do they have a need that might be unfulfilled, perhaps especially when they are fatigued? Some dementia experts, for example, have linked sundowning to caregiver fatigue. We, too, are tired at the end of the day, and may not be as "clued in" to the needs of our loved ones with dementia. For much of her later years, my mom struggled with feeling cold all the time. When her cognitive reserve was stronger, she could manage. But in the evenings, my dad found that she needed heaps of her favorite blankets in order to finally feel warm. He had to be more attuned to her needs in the times of her, and his, greatest fatigue. This is yet another reason why interdependence—caring as a team in the midst of community—is so important.

Alleviate: Keen observation leads to action. As we work to discern patterns and map out routines, we can also focus on relieving potential sources of stress. As we anticipated my mom's sundowning, we focused on her feeling of comfort, and tried not to make evenings too overwhelming. Perhaps this meant an early dinner, so that her nighttime routine could be complete prior to the onset of sundowning. Early in the course of her cognitive impairment, she had still relished lively dinner conversation. But her cognitive reserve began to weaken, and it became clear that a busy dinner, especially later in the evening, might lead to discomfort. How we aim to alleviate stress depends much on our observations about what might be causing it. But it also might help to avoid activities, at certain times of the day, that might seem like insurmountable hurdles. Trying, for example, to complete hygiene—teeth brushing, skin care, bathing, and the like—toward the very end of the day may not go well. Lastly, augmenting a feeling of rest can help. Some research, for example, has found that person-centered music therapy can reduce symptoms of sundowning. Importantly, this is not just any soothing music, but music that someone with dementia has previously enjoyed, and previously found calming. If she likes jazz, play jazz.

As we've emphasized in these pages before, care is the best medicine. This is as true for sundowning as for other challenges along the dementia journey. Anticipation, observation, and alleviation are forms of caring carried out with an understanding of the effects of cognitive weakening and fatigue. In that, we can be strong.