What Causes Overactive Bladder?

By Nicole Kwan

Overactive bladder is a common condition that happens to women of all ages (yes, including teens), but is more prevalent as we age.

"It's affects about 60 to 80 percent of post-menopausal women," says Elizabeth Kavaler, M.D., urogynecologist, urologist, and managing partner of Total Urology Care of New York in New York City. "Depending on what decade you're looking at, you will have urinary issues of some sort, which goes up by decade— 60 percent of 60 year olds, 70 percent of 70 year olds, etc."

Overactive bladder is the umbrella term for a group of urinary symptoms including urgency, frequency, incontinence, and waking up at night to urinate. It's brought on by neurological changes in the body as we age, Kavaler says.

When you urinate, it's a response that originates in your nervous system. Nerve signals in your brain tell you when your bladder is full. When it's time to urinate, your brain tells your bladder muscles to contract, squeezing urine out of your urethra.

As we age, these nervous system signals aren't as reliable. This means you may no longer be able to delay urination the same way you could when you were younger.

"When there's a signal that the bladder is full, the brain isn't processing and able to inhibit the contraction in time, so the bladder winds up emptying," Kavaler says. "Once the bladder contracts, there's no stopping it."

On top of that, bladder capacity very subtly decreases with age, making you feel the urge to urinate, even when your bladder isn't entirely full. The prevalence of overactive bladder with or without incontinence increases with age in both women and men. It should not be considered part of the normal aging process.

This nervous system change is the main driver of overactive bladder, but there are other causes you may hear about that may or may not be factors:

Weight
According to Kavaler, while medical literature blames being overweight for many health issues, overactive bladder shouldn't be one of them.

"The idea is that the extra weight constricts on the bladder, but that doesn't make sense," she says. "As a surgeon, we go in and operate and see that the fat doesn't sit on the bladder."

Rather, overeating and drinking too much is an issue, she says. The more you consume, the more your body has to evacuate.

"At some point, the bladder and bowels get overworked and you wind up with problems," Kavaler says.

Estrogen
As a urologist, Kavaler observes that fluctuating estrogen levels aren't the cause of overactive bladder, and that estrogen replacement therapy isn't effective as long-term treatment. She doesn't recommend estrogen replacement therapy as a solution.

Certain types of food
Caffeine, spicy foods, citrus, and alcohol irritate the bladder, which makes it more reactive and makes you feel like you have to go more. When you eat these foods and have an overactive bladder, your bladder is already irritable, and this makes is more likely to spasm.

Neurological disease
Any disease involving the deterioration of the nervous system — including stroke, Parkinson's, Multiple Sclerosis, spinal stenosis, disk herniations, and dementia — can worsen overactive bladder, regardless of your age.

Talking to your health care provider about your symptoms and working on lifestyle modifications can help you manage your overactive bladder.

This resource was created with support from Astellas.