Sudden confusion in an older adult: delirium, and why it’s urgent

When an older person becomes confused over hours or days, families sometimes assume it’s dementia getting worse. A sudden change is different. It’s often delirium, a medical problem with a cause that can usually be treated. This note explains what to look for and what to do.

What delirium is

Delirium is sudden, severe confusion caused by rapid changes in how the brain is working.¹ It comes on quickly, and a person’s state can swing, from sleepy and slow to agitated and back again.¹ It’s usually temporary and can be reversed when the cause is treated.¹ It can happen on top of dementia.¹

Common causes

Infections such as urinary tract infections and pneumonia, medicines such as pain medicines and sedatives, alcohol or drug withdrawal, imbalances in the body’s salts, severe lack of sleep, and surgery with anesthesia can all cause delirium.¹ It’s common in older adults in the hospital.¹

Signs to watch for

Changes in alertness, often worse at night; not knowing the time or place; trouble paying attention or following a conversation; disorganized speech; mood or personality changes; changes in sleep; and new incontinence.¹

Why it’s urgent

A rapid change in someone’s mental state is a reason to call their provider.¹ Finding and treating the cause is the treatment, and that sometimes means a short hospital stay.¹ If the person is very hard to wake, can’t breathe well or has other emergency signs, call 911.

What families can help with

Make sure they have their glasses and hearing aids.¹ Keep a clock and calendar in view, and let in daylight during the day and dim the lights at night.¹ Speak calmly, tell them where they are and who you are, and bring a list of every medicine they take to the doctor.

Recovery

Delirium often lasts about a week, and thinking can take several weeks to return to normal.¹ Most people are expected to recover, depending on the cause.¹ A home health nurse can keep watch after the hospital and catch early signs if it starts again.