A Better Understanding of Nocturia in Patients with Interstitial Cystitis
Abstract & Commentary
By Frank W. Ling, MD, Clinical Professor, Department of Obstetrics and Gynecology, Vanderbilt University School of Medicine, Nashville, TN, is Associate Editor for OB/GYN Clinical Alert.
Dr. Ling reports no financial relationship relevant to the field of study.
Synopsis: Both urgency and bladder pain can lead to nocturia in patients with interstitial cystitis.
Source: Warren JW, et al. Nocturia in insterstitial cystitis/painful bladder syndrome. Urology 2011;77:1308-1312.
In this case-control study, a well-established data-base of patients with interstitial cystitis/painful bladder syndrome (IC/PBS) was used to identify women with nocturia. The authors studied information from two data sets: a) baseline and follow-up interviews and b) self-administered questionnaire. Nocturia was associated with both urgency and bladder pain to varying degrees. Both symptoms also were perceived by the subjects to be the reason for awakening. For many patients, bladder pain either directly awakened them or indirectly caused awakening by triggering a sensation of urgency to void.
The various subtleties involved with this topic are fascinating ... at least they are to me. Taking the history is one thing, and then trying to figure out the significance of those symptoms and events is another. When I see patients referred to me for chronic pelvic pain, dyspareunia, or voiding problems, it surprises me to find many who have never been questioned about and/or treated for nocturia. Based on what we know about IC/PBS, the history of nocturia is a significant finding, so the presumed take-home message is that we should ask about this symptom routinely.
Similarly, appreciating a tender bladder on physical examination is an important aspect of determining the source of pain. This requires a conscientious and inquisitive provider who is able to differentiate the bladder from other anatomic components (e.g., pelvic floor muscles, uterus, adnexa) as the potential source of pelvic pain. The authors help us to realize that nocturia is actually a process that includes the stimulation to awake (the subject of this study), the actual awakening, getting up from the bed, going to the bathroom, and then urinating. We are reminded that patients sometimes awaken for reasons unrelated to pain or the urge to void (e.g., noise), but use that occasion to void.
Useful for the practicing women's health provider is the knowledge that the literature tells us that nocturia is associated with diabetes, restless legs syndrome, snoring, depression, and coronary artery disease. The symptom of nocturia has four general causes: sleep disorders, reduced bladder capacity, nocturnal polyuria, and global polyuria. Pain generally is not correlated with nocturia in the general population. In contrast, since pain is the hallmark of IC/PBS, it behooves us to think of patients with the symptom of nocturia as something potentially indicative of IC/PBS.
So the next time you have a patient with chronic pelvic pain, don't forget to ask about nocturia, because it will remind you about IC/PBS as a possible diagnosis. Similarly, even if the patient doesn't specifically mention nocturia, the physical examination finding of a tender bladder might lead you to a diagnosis missed by others.