Dementia-Related Psychosis
Psychotic symptoms, including delusions and hallucinations, are frequently seen in older adults with dementia, particularly Alzheimer's disease (AD) and Lewy body dementia (LBD). As cognitive decline progresses, the likelihood of experiencing these symptoms increases and can impact the rate of decline and caregiver burden.
Alzheimer's Disease
Delusions such as believing belongings are being stolen or a spouse is unfaithful are common in Alzheimer's. While less frequent, visual hallucinations can also occur. These symptoms are often associated with more significant cognitive and functional impairment and are linked to underlying neurobiological changes, including tau pathology and neurotransmitter imbalances.
Lewy Body Dementia
Lewy body dementia (LBD) is often characterized by vivid, detailed visual hallucinations that can appear early in the disease and fluctuate. Delusional misidentification, such as Capgras syndrome (believing a familiar person is an impostor), is also seen.
Delirium: An Acute Reversible Cause
Delirium is an abrupt state of confusion and altered awareness that can include psychotic symptoms. Unlike dementia, delirium develops quickly and is often triggered by treatable medical issues.
Common Triggers for Delirium-Induced Psychosis
Common triggers for delirium include infections (like UTIs), dehydration, medication side effects, and surgery.
Medication-Induced Psychosis
Taking multiple medications can increase the risk of psychosis in older adults.
Neurological and Medical Conditions
Other medical and neurological conditions beyond dementia and delirium can cause psychotic symptoms.
Parkinson's Disease
Psychosis, particularly visual hallucinations, is a frequent non-motor symptom of Parkinson's disease (PD). It can be caused by the disease progression or the medications used to treat it. While insight into hallucinations may be present initially, it can diminish as the disease advances.
Late-Onset Schizophrenia
Less common than secondary causes, late-onset schizophrenia (occurring after age 40) is characterized by symptoms like persecutory delusions and auditory hallucinations, though often less severe than in early-onset cases. Both genetic and environmental factors are believed to play a role.
Other Systemic Causes
A thorough evaluation for new-onset psychosis in older adults should consider other potential medical issues, including:
- Metabolic or endocrine imbalances (e.g., thyroid problems, electrolyte issues)
- Nutritional deficiencies (e.g., low vitamin B12)
- Inflammatory or autoimmune disorders
- Infections (e.g., HIV, neurosyphilis)
- Structural brain issues (e.g., tumors)
Non-Pharmacological and Environmental Factors
Psychosocial and environmental factors can also contribute to or worsen psychotic symptoms. Social isolation, depression, and sensory impairments like vision or hearing loss can lead to paranoia or hallucinations. Stressful life events, such as grief or moving, can also be triggers. Addressing sensory issues and providing support during transitions can be helpful.
Differentiating Major Causes
Distinguishing between the various causes involves evaluating the onset, duration, and specific symptoms. For a table outlining key differences between Delirium, Dementia-Related Psychosis, Late-Onset Psychosis, and Medication-Induced Psychosis features like onset, course, and types of hallucinations/delusions, refer to {Link: US Pharmacist https://www.uspharmacist.com/article/nonpsychotropic-medicationinduced-psychosis}.
Conclusion
Psychotic cognitive symptoms in the elderly can arise from various sources like dementia, delirium, medication side effects, or late-onset schizophrenia. A comprehensive evaluation is vital for proper diagnosis. Management involves treating the specific cause, reviewing medications, and providing a supportive environment. For more information on geriatric health, consult resources from the {Link: National Institute on Aging https://www.nia.nih.gov/}.
