Delirium – Symptoms and Causes

Overview

Delirium is a rapid decline in thinking ability and awareness. This condition develops quickly, often within hours or days. Several factors can trigger delirium.

These factors include severe illness, body chemical imbalances like low sodium, medications, infections, surgical procedures, and substance use or withdrawal.

This condition is sometimes mistaken for dementia because of similar symptoms. Healthcare professionals often need information from family members or caregivers to make an accurate diagnosis.

Key factors that can cause delirium:

• Severe or prolonged illness
• Chemical imbalances in the body
• Medication effects
• Infections
• Surgery
• Alcohol or drug use/withdrawal

The sudden onset of symptoms is an important distinguishing feature of delirium, as it typically appears much more quickly than other cognitive conditions.

Signs and Symptoms

People with delirium may struggle to focus on conversations or topics. They often get fixated on one idea instead of answering questions properly.

They’re easily distracted by things around them. Some withdraw from activities and don’t respond much to their surroundings.

Thinking Difficulties

Thinking problems are common with delirium. People may forget recent events or have poor memory. They might not know where they are or even who they are.

Speaking can become difficult, with trouble finding words or making sense when talking. Understanding what others say can be challenging. Reading and writing skills may also suffer.

Emotional and Behavioral Changes

Delirium affects emotions and behavior in several ways:

• Feeling anxious, fearful, or suspicious
• Experiencing depression
• Getting angry easily
• Feeling unusually happy or excited
• Showing little interest in things
• Mood swings that happen quickly
• Changes in how they normally act
• Hallucinations (seeing things others don’t)
• Being restless, worried, or combative
• Making unusual sounds like moaning or calling out
• Becoming very quiet and withdrawn (common in older adults)
• Moving more slowly than usual
• Sleep pattern changes
• Day and night confusion (sleeping during day, awake at night)

Delirium Types

Medical experts recognize three main types of delirium:

1. Active Delirium: People with this type appear restless and may pace around. They often seem anxious, have quick mood changes, or see things that aren’t real. They may resist help or care.

2. Quiet Delirium: People with this type appear inactive with reduced movement. They seem drowsy or sluggish and may stare blankly. They don’t interact much with family or others.

3. Mixed Delirium: This combines both types. The person switches between being restless and sluggish, sometimes very quickly.

Delirium vs. Dementia

Telling delirium and dementia apart can be challenging, and some people have both conditions. Here’s how they differ:

Feature	Delirium	Dementia
How it starts	Appears quickly (hours or days)	Develops slowly (months or years)
Attention	Clearly impaired	Usually normal in early stages
Symptom changes	Can change several times daily	Remains fairly constant day to day

Dementia involves a gradual decline in memory and thinking due to brain cell damage. Alzheimer’s disease is the most common cause.

People with dementia often develop delirium, but having delirium doesn’t mean someone has dementia. Testing for dementia shouldn’t happen during a delirium episode since results won’t be reliable.

When Medical Help Is Needed

If you notice delirium symptoms in someone you know or care for, talk to their healthcare provider right away. Your observations about the person’s typical thinking abilities and current symptoms will help with diagnosis and finding the cause.

For someone in a hospital or nursing home showing these symptoms, inform the nursing staff or doctor promptly. Staff members might not have noticed the changes. Older people in hospitals or care facilities face higher risks of developing delirium.

Causes

Delirium happens when brain signals don’t work properly. It can stem from one or multiple factors, and sometimes doctors can’t identify the exact cause.

Several medical conditions can trigger delirium. These include strokes, heart attacks, worsening lung or liver disease, and injuries from falls. Body imbalances like low sodium or calcium levels also play a role.

Infections are common triggers, especially in specific populations:

• Urinary tract infections and pneumonia in older adults
• Fever with infection in children
• COVID-19, flu, and other respiratory infections

Medications can cause delirium, particularly those treating:

• Pain
• Sleep disorders
• Anxiety and depression
• Allergies
• Parkinson’s disease
• Muscle spasms

Substance-related factors contribute significantly to delirium cases:

• Alcohol or drug use
• Withdrawal from substances
• Poison exposure (carbon monoxide, cyanide)

Physical and emotional stressors increase risk as well:

• Severe or terminal illness
• Surgery requiring anesthesia
• Nutritional deficiencies
• Dehydration
• Sleep deprivation
• Extreme emotional distress
• Uncontrolled pain

In many cases, delirium results from a combination of these factors rather than a single cause. For example, an elderly person with an infection might develop delirium when started on a new medication.

Factors that Raise Delirium Risk

Hospital stays raise the chance of delirium, especially after surgery or in the intensive care unit. Older people and nursing home residents face higher risks.

Several health issues can make delirium more likely:

• Existing brain conditions (dementia, stroke, Parkinson’s disease)
• Having had delirium before
• Poor vision or hearing
• Several medical problems at once

Complications

Delirium can be short-lived, lasting only hours, or it can persist for weeks or months. Recovery time typically shortens when the underlying causes are properly addressed.

The outcome largely depends on a person’s health and mental condition before delirium began. Individuals with pre-existing dementia may experience worsened cognitive function following a delirium episode. Those in better overall health generally have a higher chance of complete recovery.

For people with serious or long-term illnesses, delirium can have more severe consequences. They might not return to their previous level of cognitive function. Serious complications can include:

• Overall health deterioration
• Poorer surgical outcomes
• Need for extended care facilities
• Higher mortality risk

Prevention

Preventing delirium involves addressing potential risk factors before they trigger an episode. Hospital environments can be particularly challenging due to frequent room changes, procedures, noise, and poor lighting conditions.

Several strategies can help reduce delirium risk:

• Maintain good sleep habits – Create a restful environment.
• Support orientation – Keep clocks and calendars visible.
• Ensure comfort – Manage pain effectively.
• Minimize disruptions – Reduce unnecessary room changes.
• Promote natural light – Open curtains during daytime.

Sleep medications like diphenhydramine should be avoided, as these can sometimes worsen confusion. Instead, non-medication approaches to promoting sleep and reducing anxiety are preferred.

Medical staff and family members can work together to create a more stable environment. This can help to prevent delirium or reduce its severity when it does occur.