Bladder pain and discomfort, as well as urinary urgency and frequency, are common and bothersome symptoms seen in the general population. Clinical diagnostic terms used to describe these symptoms include interstitial cystitis (IC), painful bladder syndrome (PBS), chronic prostatitis, and overactive bladder (OAB), but there is tremendous overlap between these entities, and the distinction between them is based more on imminence than evidence. Pain and/or sensory sensitivity have been suspected to play a role in the pathogenesis of both bladder pain and urinary urgency/frequency. However, there has never been a study to determine whether entities such as IC/PBS and OAB might merely represent different points in a continuum of bladder sensory sensitivity. Moreover, we know of no studies that have directly compared whether sensory sensitivity in the bladder is related to global (i.e. CNS-mediated) sensory sensitivity. In the proposed study, a team of investigators with complementary expertise will perform a population-based study assessing bladder and overall sensory sensitivity, in a cohort of women chosen to be representative of the general population with respect to the entire continuum of bladder pain (from none to severe), and symptoms of urgency/frequency. These individuals will undergo urodynamics to measure sensory sensitivity in the bladder, as well as pressure pain and auditory loudness thresholds.
Our Specific Aims are to demonstrate that in the population, 1) sensory sensitivity in the bladder is related to sensory sensitivity elsewhere in the body, suggesting that this is a CNS-driven mechanism, and 2) those individuals in the population that have more pronounced global sensory sensitivity will display: a) more bladder pain, b) more urgency/frequency, and c) more other symptoms of centrally-mediated pain states, such as pain elsewhere, fatigue, and insomnia. We feel that these studies are crucial to better understand the relationship between sensory sensitivity and urinary symptoms, and to add to the evidence necessary to appropriately diagnose and treat these symptoms and individuals.
Bladder symptoms such as pain and urgency are very common, and treatments are poorly effective. These studies will examine for clinical evidence of global pain hypersensitivity in these patients. If a global pain abnormality is identified, additioal studies can be done to examine the etiology of these symptoms and design novel treatments that are focused on central, rather than peripheral, pathophysiology.