In elderly people, symptoms can arise more quickly due to several age-related factors that increase vulnerability to infection. As people age, the immune system weakens, making it harder to fight off infections, including UTIs. Other contributing factors include:

• Decreased fluid intake: Low fluid consumption reduces the frequency of urination, which prevents the regular flushing of bacteria from the bladder. A high caffeine intake can also irritate the lining of the bladder, creating an environment vulnerable to infection.

• Diabetes: Uncontrolled blood sugar levels can result in glucose being passed into the urine, creating a high-sugar environment that promotes bacterial growth.

• Urinary retention: A weakened bladder or pelvic floor muscles can lead to incomplete bladder emptying, allowing bacteria to linger and multiply.

• Urinary catheters: Catheters can introduce bacteria directly into the bladder, increasing the risk of infection. Since 2017, around 0.73% of elderly patients over 70, and 1.22% over 80 live with a urinary catheter.

• Bowel incontinence: Bacteria from the stool, such as E. coli, can enter the urinary tract and cause infections. 1 in 5 elderly adults over the age of 65, as well as over the age of 80, are more likely to face frequent leakages from bowel incontinence leading to a UTI.

• Enlarged prostate or immobility: These conditions can make proper bladder emptying more difficult, particularly in men, and prolonged bed rest can increase the risk of UTIs, and bed ridden patients are more likely to contract an infection.

• Kidney stones: These can obstruct urine flow, creating an environment where bacteria can thrive.

In the elderly, urinary tract infections are not always present with the same symptoms as in a younger person.

Due to a weakened immune response, common signs (shown above) such as cloudy urine or frequent urination might be absent. Also, if the individual has a condition such as dementia, Alzheimer's disease or has had a stroke, they can often struggle to communicate their discomfort, making a prompt diagnosis more challenging.

This can be further complicated by the fact that a common sign of a UTI in an elderly person is confusion. This may not be recognised as a sign of a UTI, especially if they already have a condition that has caused cognitive decline, and this could make it harder to recognise a UTI as the underlying cause. For carers and family members, this means it is important to stay vigilant and to monitor these subtle signs.

Key atypical symptoms include:

• Sudden confusion or delirium, often misinterpreted as cognitive decline.

• Unexpected behavioural changes such as increased agitation or hallucinations.

• Deterioration in motor skills or coordination, which could manifest as unexplained falls.

• Acute changes in behaviour or function, which are critical to monitor, might be the only indicators of a UTI.

UTIs can significantly affect the cognitive function of the elderly, particularly those already suffering from dementia. 

Symptoms, such as sudden confusion or altered mental state, should prompt immediate medical evaluation to rule out a urinary infection. These symptoms are often misjudged as a rapid progression of dementia, yet timely treatment can reverse such changes.

• Reduced Mobility: Limited ability to move independently can hinder regular bathroom use, increasing the risk of urine retention and infection.

• Cognitive Impairment: Dementia can cause forgetfulness about regular toileting and personal hygiene, key factors in UTI prevention.

• Incontinence: Common in dementia, incontinence increases moisture and bacteria around the urinary tract, promoting infections.

• Weakened Immune System: Aging and dementia can weaken the immune system, reducing the body’s ability to fight off infections.

• Communication Barriers: Dementia can impair the ability to communicate discomfort or symptoms of a UTI, leading to delayed diagnosis and treatment.

Diagnosing UTIs in the elderly can be challenging due to vague and atypical symptoms such as confusion or generalised weakness, which can be mistaken for other conditions in the elderly. 

A urinalysis (dipstick) test is often used to diagnose a UTI. Observation of the urine itself is also important, as infected urine is often cloudy. If these initial observations indicate that a UTI may be present, then a sample of urine can be sent to a lab to identify the bacteria responsible. This will determine the most effective antibiotic treatment to use. Home UTI tests are available but may lack accuracy due to the common presence of bacteria in the urine of older adults.