What Can Trigger A Sudden Personality Change In Elderly Adults?

Sudden personality changes
Older people can experience personality changes dues to circumstances in their lives, but often the changes are related to dementias, depression, vision problems, or medication change. They may become confused, aggressive, or uninterested in life. A visit to the physician for evaluation can determine the reason for personality changes.

As your loved one ages, you may notice them exhibiting personality changes. They may lose interest in things they’ve enjoyed doing before or experience social withdrawal. Such shifts in personalities and behaviors can be caused by health conditions like dementia — which affects one in 10 Americans over 65.

What Are The Behavioral Changes That Can Occur In The Elderly?

It’s not uncommon to see frequent mood swings and pronounced behavior changes in older people — especially if you’re one of those family caregivers or in-home care professionals looking after aging parents. 

These are the most common behavior problems that you may encounter:

Social Isolation And Apathy

Older people tend to withdraw from society and lose interest in engaging with others. As they lose their enthusiasm and social connection, they become more prone to depression. 


Confusion And Sundowning

They may also get confused about time, day, and location. Aggravated by memory lapses, they may further forget about recent events and important life milestones. The confusion that happens later in the day is called sundowning.

Aggression And Hostility 

Many older adults display aggressive behavior — which may range from anger outbursts to excessively using curses and offensive language. They may also appear unfriendly because of their temper tantrums and mood changes.

Impulsive And Compulsive Behavior 

Though obsessive-compulsive disorder (OCD) typically starts in young adulthood, researchers have found that such behaviors may peak again after age 65. 

Older people may repetitively do things to balance off their anxiety. In other cases, they may do compulsive hoarding, which can be caused by forgetting that they already own a particular thing.

Paranoia, Delusions, And Hallucinations

These are some of the most difficult behavior issues that caregivers face: When their aging patient makes false accusations, believes someone is trying to harm them, or sees things and people who aren’t really there.

What Can Cause A Sudden Personality Change In Elderly Adults?

Different factors affect one’s quality of life and well-being as they grow older. When you see someone demonstrating frequent and significant changes in their personality, the underlying cause may be one of the following:

Lack Of Sleep

When a person is sleep-deprived, they are more prone to anger and aggression. The body needs adequate sleep to maintain healthy brain function and mental wellness. 

Sleep issues mimic dementia

Hearing And Vision Problems

One’s sense of sight and hearing is essential to daily functioning. If they develop issues with any of the two (or both), they may be embarrassed and display unusual behaviors (e.g., withdrawal). 

Hearing problems

Mental Health Issues

When an elderly is depressed or chronically sad, they will be more likely to be aggressive or apathetic. Another mental health concern that can cause changes in behavior is bipolar disorder (where one experiences episodes of mania or hypomania). 

Urinary Tract Infection (UTI) 

UTI occurs when bacteria invade one’s urinary system. In many cases, a person with a UTI displays personality changes such as increased agitation, irritability, and confusion.

Medication Side Effects

Seniors tend to take more medication than younger people. If they have existing medical issues, they will be prescribed more medicines. However, some medications, like certain antidepressants, can alter behavior. 

Post-Concussion Syndrome (PCS)

If an older adult has PCS, their brain cells are damaged, and their brain function isn’t working like usual. As a result, they will behave differently — a consequence that can last for months or even years.

Brain Tumor

An abnormal growth of tissue and the brain can cause headaches, slurred speech, seizures, and personality changes.

Brain tumor


Dementia is a group of brain disorders marked by significant cognitive impairment to the point that it affects the patient’s daily living. Frontotemporal dementia is a type of dementia that concerns certain areas of the brain: the frontal lobe and temporal lobe; Alzheimer’s disease, on the other hand, creates plaques in the brain that causes brain cell damage.

The common thing that ties different dementias is that patients tend to exhibit mood and behavior changes.

What Are The Warning Signs Of An Elderly Person’s Mental Health?

As people enter old age, they become more prone to developing mental health issues. In fact, about 20% of older people experience some type of mental concern

Caregivers caring for elderly people don’t just have to watch out for signs of dementia; they must also know how to spot a mental illness. These are some must-know warning signs:

  • Changes in appetite
  • Changes in personal hygiene
  • Sleep problems
  • Memory loss
  • Feelings of intense sadness that last over two weeks
  • Social withdrawal
  • Trouble doing everyday tasks
  • Chronic fatigue
  • Confusion and disorientation
  • Unexplained physical symptoms (e.g., pain)

What Can Cause A Sudden Change In Personality?

Older adults may have a sudden personality change for various reasons. Apart from the causes discussed above, other culprits include stroke (which can disrupt oxygen supply to the brain), panic attacks (periods of extreme fear), dehydration, hunger, and menopause or andropause.

It’s best to consult a healthcare provider to identify what causes these changes. A physician will conduct the necessary tests and evaluations to arrive at a proper diagnosis and design a treatment or care plan.

Is Personality Shift Normal Aging?

The aging process can take a toll on someone’s mental health. 

Older people have to deal with the changes that happen in their bodies and the changes that occur in their immediate surroundings (e.g., changes in dynamics among family members) and in society in general (e.g., the emergence of new technologies).

Additionally, there’s the possibility that they may develop medical conditions or their existing ones may worsen.

These things can cause their personality to shit, and they may become more introverted and moody. 

Personality change

What Is The Difference Between Personality Change And Dementia?

Dementia is a broad term encompassing different brain disorders impairing one’s cognitive function. Apart from the aforementioned Alzheimer’s disease and frontotemporal dementia, other types include vascular dementia and Parkinson’s disease dementia.

In senior care, changes in one’s personality and behavior are part of the criteria used to diagnose such disorders. These are considered one of the most common symptoms of dementia.

Why Do The Elderly Become Mean?

If you’re at your family home, you may be in a situation where an elderly parent or other aging family members act out and get cranky. It can be part of their way of resisting or coping with the changes within and around them. 

It’s also a way for them to say they have unmet needs. Personality changes can also be traced to underlying health conditions.

Mean old woman

Understand that it’s not their intention to become mean. On your part, you need to be more observant and look for what triggers their bad behavior. Help them regularly visit their doctor or specialist who can undertake proper interventions.

How Can Personality Changes Be Prevented Or Reversed?

If your loved one demonstrates personality and behavior concerns and a treatable condition causes it, the changes can be reversed once the underlying cause is addressed. For instance, if it’s due to hearing issues, giving them hearing aids is one part of the solution.

In cases where the root cause isn’t treatable, such as dementia, what you can do is manage their symptoms. Resolve unmet needs, engage and socialize with them, and learn how to deal with challenging behaviors (e.g., validation method).

Have them undergo regular checkups and tests to prevent personality and behavior changes. Let them join a support group and do enriching activities that they like with fellow seniors. This can also help them preserve a sense of purpose and control, which leads to a better quality of life. 

Randell S.

Randell Suba is a former Physiotherapist who returned to his first love, writing. He has over a decade of online writing and research experience. Randall has experience managing the care of elderly parents who lived with his family and other relatives with dementia, so he writes in the area of senior living and care with considerable experience.

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