Millions of people suffer from the problem of over active bladder and lower urinary tract symptoms. These conditions put an adverse affect on quality of life and there are costs associated with the conditions. The ‘International Continence Society (ICS)’ defines ‘Overactive bladder (OAB)’ as urgency, with or without urgency incontinence, usually with frequency and nocturia, in the absence of infection, or other obvious pathology.
Among the above symptoms as enumerated by ICS, urgency is the most serious implication of this condition. It is defined by ICS as a sudden, compelling, difficult-to-defer desire to pass urine. It leads to other symptoms of OAB like frequency, nocturia and sometimes incontinence except in the case of patients with absent bladder sensation. The experience of urgency puts the greatest negative effect on quality of life than any of the other symptoms associated with OAB.
Majority of the patients even do not experience the problem of incontinence. Incontinence implies the reduction of one’s voluntary control on the excretory functions of the body.
Yamaguchi and colleagues from throughout Japan explain that the urgency as defined by ICS which distinguishes it from urge. Urge is a normal physiological sensation carrying the same meaning as a desire to void. However the patients suffering from OAB fail to react towards a normal urge or urgency.
Urgency, as clearly defined by ICS, is a pathological sensation which results in a compelling desire to pass urine. However it is still unclear whether urge and urgency are just two varieties of the same condition or not. Because of its subjective nature, it is difficult to distinguish between the two in a clinical or research.
The authors of ICs however adopted an innovative approach of gathering the information. They selected 21 female patients carrying the condition of overactive bladder who were selected on their ability to understand and distinguish between urgency and urge. All had experienced urgency and normal urge and authors found that they carried clear ability to distinguish between the two. The patients completed a 7 days voiding diary and the information was compiled to make the distinction clear about urge and urgency.
The participants of the study had already sought medical care to cure the conditions so they were capable enough to differentiate between the two. Among 43% urgency was felt less than once a day and some of the patients reported absence of sensation of urgency for many days together. Even among the patients who experienced urgency reported that it initiated with a normal sensation of desire to void.
The authors conclude that urgency does not seem to be a resultant factor in the symptoms of frequency that are common in OAB. They found urge sensation to be remarkably increased at any given bladder volume in their patients with OAB compared with normal subjects. Hypersensitivity was a common symptom among both the conditions.
This led the authors to believe that OAB may be more accurately defined as a hypersensitivity disorder rather than a syndrome characterized primarily by urgency as defined by ICS. Increased bladder sensitivity (hypersensitivity) seems to be driving the symptoms of urgency in the patients suffering from OAB.