People with dementia often become more confused and agitated in the evening due to a phenomenon known as **sundowning**, which involves increased confusion, anxiety, restlessness, and sometimes aggression during late afternoon and evening hours. This pattern is linked to both biological changes in the brain and environmental factors that worsen as daylight fades[1][6].
At the core of sundowning are changes in brain function caused by dementia. Dementia damages areas of the brain responsible for regulating emotions, processing sensory information, and maintaining circadian rhythms—the internal body clock that controls sleep-wake cycles. Specifically, deterioration in the **frontal cortex** (including the anterior cingulate cortex and orbitofrontal cortex) impairs decision-making and emotional regulation, making it harder for the person to filter and respond appropriately to stimuli[1]. Additionally, loss of neurons in the **locus coeruleus**, a brainstem region involved in noradrenergic signaling, increases sensitivity to stress hormones like norepinephrine, heightening reactivity to environmental triggers[1].
The disruption of circadian rhythms is a major contributor. As daylight diminishes, the brain’s internal clock struggles to adjust, leading to confusion about time and place. This can cause disorientation and increased agitation. The reduced light also affects melatonin production, a hormone that regulates sleep, further disturbing sleep patterns and increasing evening confusion[6].
Environmental factors exacerbate sundowning symptoms. Low lighting, increased shadows, and fading daylight can create visual misperceptions and fear. Sudden changes in routine, excessive noise, or overstimulating environments can overwhelm the person’s impaired brain, triggering agitation and confusion[1][5]. For example, a noisy room or unfamiliar visitors may cause stress, leading to behaviors like pacing, verbal outbursts, or wandering[3].
Physical discomfort or unmet needs often underlie behavioral changes in dementia. Pain, hunger, thirst, or the need to use the bathroom may be difficult for the person to communicate, and these unmet needs can manifest as confusion or agitation, especially when cognitive resources are lowest in the evening[5]. Caregivers should be attentive to these possibilities to help reduce distress.
Sundowning is also linked to the progression of dementia types such as Alzheimer’s disease and vascular dementia. Vascular dementia, caused by reduced blood flow and brain tissue damage, can worsen cognitive symptoms and behavioral changes, including evening confusion[4]. Alzheimer’s disease, the most common dementia, frequently involves sundowning as part of its neuropsychiatric symptoms[6].
In summary, the increased confusion of a loved one with dementia in the evening results from a complex interplay of brain changes affecting emotion regulation and circadian rhythms, heightened sensitivity to environmental stimuli, and unmet physical or emotional needs. Understanding these factors can help caregivers create calming environments, maintain consistent routines, and address basic needs to ease evening distress.
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**Sources:**
[1] Behavioral Strategies for Managing Agitation in Dementia Patients, The Supportive Care
[3] Dementia Wandering: Causes, Risks, and How to Prevent It, Alzheimer’s San Diego
[4] Vascular Dementia: Symptoms, Treatment & Prognosis, Cleveland Clinic
[5] What Is The Number One Trigger For Dementia Behavior?, Trualta
[6] Daylight Saving Time and Alzheimer’s, Alzheimer’s Association
