New therapy for overactive bladder could improve quality of life for millions of older adults

Professor Paul Yoo

Professor Paul Yoo (right) is leading a clinical trial to test a novel treatment for overactive bladder (OAB), a condition that affects 18 per cent of Canadian adults. (Photo: Luke Ng / University of Toronto).

March 16, 2017

A clinical trial funded by AGE-WELL is underway to test a novel treatment for overactive bladder (OAB), a condition that affects 18 per cent of Canadian adults—and up to 500 million people worldwide.

OAB involves the frequent and sudden urge to urinate, and may be accompanied by urinary incontinence. OAB can occur when muscles in the bladder contract involuntarily even when the volume of urine in the bladder is low.

“OAB is a huge problem that does not really get a lot of attention,” says Professor Paul Yoo, co-lead with Dr. Sasha John of the research project team from the University of Toronto’s Institute of Biomaterials & Biomedical Engineering (IBBME). “The sheer number of people that could benefit from this therapy is one of the most exciting aspects of the project.”

The condition is particularly prevalent among people over 65 and more frequently diagnosed in women. OAB may cause anxiety, social withdrawal, depression and falls from rushing to the washroom, possibly even more so when awakened from sleep. Falls are the leading cause of injury to seniors.

Yoo and his team recently discovered a new nerve stimulation target that may provide improved treatment over tibial nerve stimulation, an emerging therapy currently available to people with OAB. In pre-clinical studies, they showed that electrical stimulation of the saphenous nerve, a peripheral nerve in the leg, inhibited the bladder in similar fashion to that achieved by tibial nerve stimulation.

“The kicker is that the amplitude required to achieve this result with the saphenous nerve was much lower than with the tibial nerve,” explains Yoo.

“The saphenous nerve appears to be a more sensitive reflex mechanism and so using lower amplitude electrical pulses should be more comfortable for those with OAB. And since the saphenous nerve does not activate foot muscles—like the tibial nerve—it could be a very versatile neural target for delivering therapy to patients.”

Yoo and John were awarded almost $20,000 in funding from AGE-WELL to support a pilot clinical trial and help with other costs. The investigators have multiple allowed and pending patents on the technologies being explored by this project. The research marks the first time the saphenous nerve has been targeted for OAB electrical stimulation therapy.

The team is collaborating with Dr. Magdy Hassouna at Toronto Western Hospital on the trial involving 30 patients who are seeking relief from their OAB symptoms. Trial participants are trained by the research team to self-administer saphenous nerve stimulation at home. They are asked to operate the stimulator and treat themselves 30 minutes a day over a three-month period. Researchers expect patients to experience improvements in bladder symptoms within weeks of starting treatment.

Trial participants track their progress using a bladder diary and quality of life measures to assess the clinical benefits of the therapy. The trial is expected to finish towards the end of summer 2017.

While the team aims for an affordable, self-administered and home-based treatment, they stress the importance of patient training and ongoing care being overseen by a physician.

Current treatments for OAB have limitations and drawbacks including medication side effects, the need for invasive surgery involving costly implantable devices, or monthly clinic visits to maintain therapy benefit.

If successful, the new approach could markedly improve independence and quality of life for those affected by OAB.

“If our peripheral nerve target with a minimally invasive nerve stimulation technology turns out to be very effective, it could have a huge impact on many people and the health care system,” says Yoo.

The Canadian Continence Foundation estimates the total burden of OAB in Canada to exceed $2.5 billion annually, a figure that will likely rise as the population ages.

The lead investigators have been approached by a number of industrial partners who are interested in this novel therapy for OAB. The researchers hope to establish a new partnership through the current pilot study, and to facilitate adoption by the medical community by successfully completing a larger, randomized clinical trial.

“The AGE-WELL grant provided the crucial funding to obtain the human data that we need to get industry partners interested,” says John. “Somewhere between 20 to 60 people out of 100 will fail to respond to existing therapies and if this new treatment approach turns out to be better, then we are going to be able to help a lot of people that aren’t currently finding a successful clinical solution to their need.”


This story was originally published by AGE-WELL Network of Centres of Excellence (NCE) and is reposted with permission.