Overactive Bladder (OAB) is a common chronic problem presenting as urinary urgency and frequency in about 12% of the population. The International Continence Society defines it as “Urinary urgency, with or without urgency incontinence, usually with frequency and nocturia, in the absence of infection or other proven pathology”. The condition is commoner in the elderly and often more severe in women. OAB is unpredictable and patients may have a sudden strong urge to void with incontinence, which can be severely embarrassing. In the elderly, OAB is responsible for poor quality sleep, nocturia and falls leading to fracture. In the elderly, such fractures can set in motion a chain of events that prove terminal.
The diagnosis of OAB rests on the clinical presentation and exclusion of the many other causes that can lead to similar symptoms, such as urinary infection, carcinoma in situ, urolithiasis, chronic retention and pelvic masses. In patients with negligible residual, good uroflow and lack of other causes, a clinical diagnosis of OAB can be made. Urine analysis, residual urine check by USG, frequency volume chart and a quality of life questionnaire are recommended.
Management of OAB
The treatment of OAB consists of a combination of life style changes, improving pelvic floor muscle tone, bladder training and drug therapy. Fluid restriction is helpful in those who have large urine outputs. Antimuscarinic medication is the mainstay of drug therapy. Oxybutynin, tolterodine, solifenacin, darifenacin and trospium are some available drugs. These act by blocking the M3 receptor in the bladder. Dry mouth, constipation, blurring of vision and cognitive impairment are usual side-effects related to blockade of muscarinic receptors elsewhere. Beta-3 agonists are a new class of drug with modest benefits.
Recent Advances in OAB Managment
The current management of OAB remains unsatisfactory. Many patients discontinue therapy due to intolerable side effects or an unsatisfactory response. There are two recent options in management which have considerably enhanced our ability to manage these patients.
Botulinum Toxin can be injected cystoscopically into the bladder to control OAB. The procedure needs to be done in an operating room and the effect typically lasts for about 9months. It is effective in most patients. However, some patients may have retention and need for catheterization.
Sacral neuromodulation is another recent option that can be effective in recalcitrant OAB. An electrode is implanted into the S3 space by a minimally invasive technique. This is stimulated by a battery device, which is ultimately implanted into the buttocks. The device usually lasts about 5 years and unlike Botulinum does not cause retention. In fact, it can be used to treat select forms of voiding difficulty as well as bowel problems.
Both these newer options are expensive and need to be reserved for selected patients. For these select patients with intractable OAB, they can be of extraordinary benefit. Apollo Hospitals has become a referral center for the management of complex lower urinary tract dysfunction. Last year over 1200 patients underwent urodynamics evaluation, arguably the largest number in the country. A large number of patients have received botulinum toxin treatment and with the recent addition of sacral neuromodulation, the entire spectrum of management is available at the center.
Consultant Urologist and Transplant Surgeon,