Symptoms of Overactive Bladder

Overactive bladder (OAB) is a condition in which the frequent need to urinate undermines a person’s quality of life. It is believed to affect as many as 1 in 4 adult women and 1 in 6 adult men in the United States.

While urinary urgency, the sudden urge to empty the bladder, is the defining symptom of OAB, the failure to appropriately treat the condition can lead to an array of unexpected—and potentially debilitating—complications.

Although OAB is not life-threatening, it is a condition that can persist for years if not treated appropriately. Even so, as many as 61% of people with OAB will experience symptoms even with treatment, albeit to varying degrees.

Frequent Symptoms

OAB, also known as non-neurogenic overactive bladder, is characterized by symptoms that occur in the absence of any predisposing factor, such as a urinary tract infection, enlarged prostate, diabetes, or medications. When diagnosing the condition, healthcare providers look for four features common in people with OAB.

Urinary Urgency

Urinary urgency is the central feature of OAB, the symptom of which can occur during the day, at nighttime, or both.

Defined as the “sudden, compelling desire to pass urine which is difficult to defer,” urinary urgency is about more than “not being able to hold it” or “having a small bladder.” Rather, it is a physiological impulse that causes the sudden, involuntary contraction of the muscular wall of the bladder.

When urinary urgency occurs at night, it is referred to as nocturia. Nocturia will often manifest with an abrupt awakening from sleep and a rush to the bathroom to urinate. In people with OAB, this can occur one or more times per night. Around 50% of people with daytime (diurnal) urgency will also experience nocturia.

Due to the chronic interruption of sleep, people with nocturia will often experience daytime drowsiness, a loss of concentration, and fatigue.

Urinary Frequency

Urinary frequency, the need to urinate more frequently than normal, is typically described as having to urinate more than seven times within the course of 24 hours. Although this can occur in people who drink lots of fluids, take diuretics, or consume too much caffeine, it is considered a classic sign of OAB in the absence of any provoking factor.

Urinary frequency can occur in the absence of urinary urgency. In such cases, OAB is a less likely cause.

Polyuria

Polyuria—literally “multiple” (poly-) “urination” (-uria)—is a term often used interchangeably with urinary frequency but one that specifically describes the volume of urine output within a 24-hour period, during the day or at night.

Polyuria at night is aptly described as nocturnal polyuria, while polyuria in the daytime is called diurnal polyuria. Global polyuria, the key diagnostic measure for polyuria, is excessive urine output in 24 hours.

Polyuria is an important diagnostic sign, as excessive urine loss can lead to dehydration, excessive thirst (polydipsia), and other adverse symptoms. It is also the one feature of OAB that can be measured quantitatively.

The normal adult urine output should be anywhere from 12 to 36 mL/kg/day.

While polyuria is a central feature of OAB, it can occur with many other conditions, including diabetes, kidney disease, Cushing’s syndrome, and others.

Urge Incontinence

People with OAB often experience a form of urinary incontinence known as urge incontinence. Also referred to as “wet OAB,” urge incontinence is triggered by sudden spasms of the bladder wall that cause the spontaneous loss of urine.

Urge incontinence differs from other forms of incontinence in that urinary urgency is involved. By contrast, other types of incontinence occur without urgency and are mainly due to the failure of the urethra and pelvic floor to withstand abdominal pressure.

Urge incontinence can co-exist with another condition called stress incontinence, in which physical movement—such as coughing, laughing, sneezing, or heavy lifting—can cause you to leak urine. When they occur together, the condition is referred to as mixed incontinence.

The co-occurrence of stress incontinence can often lead to misdiagnoses, particularly in women whose symptoms may be attributed to pelvic floor dysfunction (such as caused by multiple vaginal births) rather than OAB.

Uncommon Symptoms

Other symptoms can affect people with OAB depending on the underlying cause, the person’s age or sex, and other factors. Chief among these are bowel symptoms which may be directly or indirectly linked to OAB.

Fecal Incontinence

Fecal incontinence, the sudden loss of bowel control, is more common in some groups with OAB than others.

According to a 2018 study in Neurourology and Urodynamics, older adults with OAB are far more likely to experience fecal incontinence than any other group, including older adults in the general population. A person’s sex also factors in, with women more likely to experience severe fecal incontinence than their male counterparts.

A number of co-occurring conditions appear to increase the risk of fecal incontinence in people with OAB, some of which are aging-related and others of which are not. These include irritable bowel syndrome, degenerative disc disease, fibromyalgia, and chronic fatigue syndrome.

According to the researchers, urinary and fecal incontinence may share common causes within the context of OAB, such as the deterioration of pelvic organs paired with the overactivity of smooth muscles that regulate urinary and bowel function. Further research is needed.

Constipation

On the flip side, OAB may be linked to functional constipation in women, suggests a 2017 study in BioMed Research International.

Functional constipation, also known as chronic idiopathic constipation, is diagnosed when no specific cause can be found. Women over 40 are far more likely to experience this than men.

According to the study, rectal distention significantly influences the sensation of bladder filling, leading to urinary urgency and urinary incontinence in some women. Beyond the mechanical stress placed on the organs, there may also be “crosstalk” between the neural pathways that regulate the smooth muscles of the rectum and bladder.

Complications

In the past, OAB was not thought to be a progressive disease but rather one that was variable and could fluctuate over time. There is increasing evidence that this is not the case in all people and that, if left untreated, OAB can cause a number of short-term and long-term complications.

Dehydration

Polyuria is almost invariably linked to an increased risk of dehydration. In people with OAB, in whom polyuria may be chronic, the loss of body fluids increases the concentration of urine, which acts as an irritant in the bladder. Studies have long suggested that this promotes urinary incontinence in people with OAB.

Chronic dehydration can also promote the formation of urinary crystals that develop into renal calculi (kidney stones) over time. Constipation is also a common concern.

Upper Urinary Tract Infections

The persistent stress placed on the bladder from years of muscular contractions can induce structural changes to the bladder itself, including:

• Trabeculated bladder: In which the bladder is no longer able to expand when filled or contract when emptied
• Bladder diverticulum: In which weakened parts of the bladder wall start to thin and form pouches

These conditions often co-occur and are both associated with an increased risk of upper urinary tract infections (UTIs).

With a trabeculated bladder, the loss of muscle tone can cause urine to reflux (backflow) into the kidneys and establish an infection (called pyelonephritis). With a bladder diverticulum, the same can occur due to bladder outlet obstruction.

In rare cases, a bladder diverticulum can cause the organ to rupture, requiring emergency surgery.

Depression

Beyond the physical toll that OAB can inflict on the body, it can also cause serious emotional harm to people unable to cope with their urinary symptoms.

A 2016 study published in BMC Urology reported that around 30% of people with OAB meet the clinical definition of depression. Not surprisingly, the severity of depression typically corresponds to the severity of OAB symptoms.

While external factors such as social isolation, nocturia-induced fatigue, and loss of productivity at work may contribute to the onset of depression, some researchers believe there is a mechanistic link between OAB and clinical depression.

Some studies suggest that OAB is linked to the deterioration of executive function rather than the urinary tract. This is evidenced in part by a 2020 study in the Canadian Geriatric Journal in which older adults with OAB take significantly longer to complete executive function tests than a matched set of adults without OAB.

In a similar vein, diminished executive function is characteristic of major depression and may account for why OAB is often more severe in those with depression.

Other scientists hypothesize that bladder control is strongly influenced by emotions (as evidenced by people with psychiatric conditions who are at high risk of bladder dysfunction).

If so, physiological and psychological factors may perpetuate a cycle wherein OAB triggers feelings of anxiety/depression, and anxiety/depression promotes or intensifies symptoms of OAB.

When to See a Healthcare Provider

One of the primary features of OAB is a diminished quality of life. As such, if any urological symptom is causing you persistent anxiety or impeding your ability to function, ask your healthcare provider for a referral to a urologist for further evaluation.

It is also important to recognize the symptoms of OAB and not to dismiss them as a “part of getting old.” Although OAB is more common in older adults, most older adults do not get it.

For this reason, you should see a urologist if you experience:

• A constant urge to pee
• Frequent urination (more than seven times daily)
• Bladder spasms
• Incontinence
• Leaking of urine
• Nighttime urination (one or more times nightly)
• Bedwetting

If treated appropriately, symptoms of OAB may be greatly reduced and in some cases disappear altogether.