Persistent Postural Perceptual Dizziness: An Uncommon Diagnosis May Be More Common Than Doctors Once Thought
Tom Bishop started experiencing dizziness in 2013 and saw several neurologists and otolaryngologists over the years with no conclusive diagnosis. “I had no sensation of whirling. It was more like a constant feeling that I was going to fall,” says Bishop, who is 74.
In February 2022, one of his specialists referred him to Aniruddha “Alok” Patki, MD, a fellowship-trained neurotologist and assistant professor in the Department of Otorhinolaryngology at McGovern Medical School at UTHealth Houston. Dr. Patki, whose clinical interests include hearing loss, Ménière’s disease and other balance disorders, tinnitus, chronic ear disease, and vestibular schwannomas, told Bishop he thought he knew what was wrong and wanted to run some tests.
“After years of doctor visits, this was wonderful to hear,” Bishop says. “My wife and I couldn’t believe it.”
Dr. Patki suspected persistent postural perceptual dizziness (PPPD), a chronic vestibular disorder characterized by fluctuating symptoms of dizziness, unsteadiness, or non-spinning vertigo aggravated by environments with moving visual stimuli. “He tested Tom’s balance and in less than two weeks we had a diagnosis. It was like a miracle,” says Kim Cadena, Bishop’s wife.
“The dizziness patients with PPPD experience is not the classic sensation of spinning,” Dr. Patki says. “What we see instead is visual dependence, a phenomenon where people experience dizziness when they see something else move, rather than when they themselves are in motion. A common complaint I hear is that they can no longer go to the grocery store without feeling dizzy. I ask these patients a lot of questions: Do they feel dizzy when they’re in a crowd? Do they have the same feeling when they’re scrolling down a page on a computer? Visual dependence is a strong marker for PPPD. Another marker is symptoms that are present at least 15 days out of 30, but not all the time.”
PPPD is a relatively new diagnosis in name only; the condition has been reported in the medical literature for more than a century, without being named. “I heard very little about it in residency and more during fellowship training, but I suspect it’s fairly common because we are beginning to see more cases,” he says.
What causes PPPD? The brain uses inputs from the vestibular system, visual system, and proprioception – the sense of body position and self-movement – to allow people and animals to find equilibrium. “The brain combines all of this information to identify obstacles in the environment and perceive the tilt of the horizon. The data is communicated to the legs, spine, and core. In patients with PPPD, an unknown series of events has caused the vestibular system to rely more on the visual system than is normal,” he says.
“PPPD may coexist with other vestibular disorders, which can confuse the diagnosis, so I am not surprised it took so many years to diagnose Mr. Bishop’s problem,” he adds. “There is no one ‘dizziness doctor’ – you may need to see an ENT, neurologist, endocrinologist, or a spine surgeon. Your doctor may suspect something but can’t quite put a finger on it. This makes PPPD a frustrating journey for the patient.”
Automobile accidents, sudden traumatic events, and other medical conditions that cause dizziness may trigger it. It’s also often associated with anxiety or depression. “Something happens that causes the brain to change the way it processes inputs into the nervous system,” Dr. Patki says. “We treat PPPD with antidepressants, which in some way reset the abnormal way the brain processes visual information.”
He prescribed Bishop a small dose of venlafaxine, sold under the brand name Effexor®. Within days, his sensation of dizziness stopped. Dr. Patki also referred him to TIRR Memorial Hermann for vestibular therapy to retrain his balance.
“Even though the medication stopped the dizziness, Tom still had discomfort in certain situations, such as in crowds,” Cadena says. “We both feel that the vestibular therapy was very important in his recovery. I especially appreciated all the questions Dr. Patki asked Tom to understand his condition and determine a diagnosis. These were questions no one else had ever asked. He was a great listener and very thorough.”
“When I first prescribe an antidepressant, I ask the patient to see me again in six weeks,” Dr. Patki says. “The official recommendation is that patients continue on the medication for a year before trying to stop it, and I suggest that they try it for at least several months to see if symptoms return. A high proportion of patients are happy with their results and prefer to continue on the medication. A few are on several medications and want to try stopping it to see if symptoms return. There’s no way to predict without trying. I’m just happy we got a win for Mr. Bishop. He did very well.”