The sunset syndrome, which affects people with dementia – 08/16/2023 – Equilibrium and Health

The term “sunset syndrome” (or twilight syndrome) is sometimes used to describe the tendency in people with dementia to feel more confused in the late afternoon and during the night.

First, it needs to be emphasized that the term is very simplistic and can cover a wide variety of behaviors in many different contexts.

When assessing behavioral changes in dementia, it is always better to hear a complete and accurate description of what the person is doing at these times, rather than accepting that they are suffering from the syndrome.

This frequently described set of behaviors includes confusion, anxiety, agitation, pacing, and following another person.

This can manifest itself differently depending on the degree of dementia, the individual’s personality and past behavior patterns, and the presence of specific triggers.

So why do these altered behaviors tend to pop up at specific times of the day? And what should we do when they happen to a loved one?

Less sensory information

We all interpret the world through the information our brain receives through our five senses.

The main senses are sight and hearing.

Imagine the difficulty you would have if you were asked to perform a complex task while in a dark environment.

People living with dementia equally rely on sensory information to correctly understand and interpret their surroundings.

As light diminishes towards the end of the day, so does the amount of sensory information available to help a dementia patient make sense of the world.

The impact of this on a brain that already has difficulties integrating sensory information can be significant, resulting in greater confusion and unexpected behavior.

cognitive exhaustion

We’ve all heard that we only use a fraction of our brain power, and it’s true that we have more brain power than is generally needed for most daily tasks.

This “cognitive reserve” can be used when we need to perform complex or stressful tasks that require more mental effort.

But what if you don’t have much cognitive reserve?

The changes that eventually lead to the symptoms of Alzheimer’s disease can begin to develop up to 30 years before these symptoms appear.

In that time, simply put, the condition depletes our cognitive reserve.

It’s only when the damage done is so significant that our brains can’t compensate for it that we develop the first symptoms of Alzheimer’s and other forms of dementia.

So when someone has the first symptoms of dementia very early, much of the damage has already been done.

Cognitive reserve has been lost and symptoms of memory loss finally become evident.

As a result, people living with dementia have to do a lot more mental effort during the day than most of us.

We’ve all felt cognitively drained, tired, and maybe a little irritable after a long day of performing a difficult task that required a high level of mental effort and concentration.

People living with dementia have to put in a similar amount of mental effort just to go about their daily routine.

So it’s not surprising that after several hours dedicated to constant mental effort just to survive (often in an unfamiliar location), they tend to feel cognitively drained.

What should I do?

The homes of people with dementia should be well lit during the afternoon and evening, when the sun is going down, to help the person with dementia to integrate and interpret sensory information.

A short nap after lunch can help alleviate cognitive fatigue later in the day. This gives the brain an opportunity to “recharge”.

However, there is no substitute for a more comprehensive assessment of other causes that may contribute to behavioral change.

Unmet needs such as hunger or thirst, the presence of pain, depression, boredom or loneliness can all contribute, as can stimulants such as caffeine or sugar if consumed too late in the day.

The behaviors often described with the overly simplistic term “evening syndrome” are complex and their causes tend to be individual and interrelated.

As is often the case in medicine, a specific set of symptoms is best managed by better understanding the causes.

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Steve Macfarlane is Director of Clinical Services at Dementia Support Australia and Associate Professor of Psychiatry at Monash University.

This article originally appeared on The Conversation and is reprinted under a Creative Commons license. You can read the original in English here.