Fig. 1.1
Prevalence of self-reported difficulty emptying bladder by gender and age (Permission obtained Valente et al. 2014)
A number of coexisting conditions have been implicated in UAB development and progression. The DESx group was more likely to report diabetes, stroke, and recurrent bladder infections ≥3 per year (Table 1.1). Additionally, women with a history of hysterectomy or prolapse/incontinence surgery were significantly more likely to have difficulty with bladder emptying. UAB was more common in men with prior prostate surgery.
Table 1.1
Self-reported coexisting conditions related to underactive bladder
Characteristic/question | UAB question positivea | UAB question negative | N |
|---|---|---|---|
Q3: Do you have any of the following problems? (check all that apply) | N (%) | ||
Diabetesb | 39 (34.5) | 74 | 113 |
Strokeb | 8 (40.0) | 12 | 20 |
Cancerb | 14 (29.8) | 33 | 47 |
Parkinson’s | 0 (0.0) | 5 | 5 |
Heart disease | 27 (25.5) | 79 | 106 |
Multiple sclerosis | 2 (28.6) | 5 | 7 |
None | 40 (16.1) | 208 | 248 |
Othersb | 47 (27.8) | 122 | 169 |
Persons reporting UAB symptoms were twice as likely to describe their health as “poor” or “fair” compared to those without the complaint (26 % vs 12 %, p <0.001). Those with difficulty emptying their bladder were 70 % more likely to describe their health as “poor” or “fair” than expected (Valente et al. 2014). According to an epidemiologic survey on LUTS in Japan (Homma et al. 2006) of 10,096 men and women 40 years old or older and the analysis of responses from 4,570 subjects (effective collection rate 45 %), prevalence rates for slow stream more than once a week were 37 % in men, 18 % in women, and 27.0 % in the overall population. Prevalence rates for slow stream more than once a day were 28 % in men, 13 % in women, and 20 % in the overall population. Similarly, the prevalence rates for feeling of incomplete emptying more than once a week were 26 % in men, 10 % in women, and 18 % in the overall population.
Epidemiology Based on Urodynamic Perspectives
Abarbanel and Marcus (2007) reported a study of 181 community-dwelling elderly with LUTS identified impaired detrusor contractility (IDC) in urodynamic studies in 48 % of men and 12 % of women. Of the men in this study, 40 % were found to have concomitant bladder outlet obstruction (BOO); 10 % of those with IDC had BOO. 16 % were found to have IDC in the absence of involuntary contractions or obstruction of the bladder outlet
A recent study by Jeong et al. (2012) examined the prevalence of DU in 1,179 elderly men and women aged over 65 years with nonneurogenic voiding dysfunction presenting with LUTS and found that upwards of 40 % of men and 13.3 % of women met urodynamic parameters for DU, and the numbers increased with age in both groups.
Studies based on urodynamic parameters suggest the prevalence of DU is higher among men than women. In addition, the presence of bladder outlet obstruction, diabetes, neurologic diseases, and retention complicates the picture and appears to be positively associated with UAB. These studies imply that DU is common and morbid, yet the true prevalence remains largely unknown.
Bladder Outlet Obstruction and UAB
The relationship between BOO and UAB/DU is poorly understood and complex. Not all men with BOO develop UAB/DU and similarly not all men with UAB/DU have BOO (Thomas et al. 2005). Detrusor contractility is commonly and irreversibly impaired due to chronic BOO and may persist even after the obstruction is relieved. Following 69 men for over a decade diagnosed with DU (Qmax <15 ml/s, Pdet@Qmax <40 cmH2O) and initially managed with watchful waiting, Thomas et al. (2005) found no significant deterioration in symptomatic or urodynamic parameters over time. Only eleven patients (16 %) failed the initial watchful waiting approach and underwent prostate surgery, 8 (12 %) due to worsening symptoms and 3 (4 %) due to acute retention. The authors concluded that DU is not progressive in the majority of men and an initial conservative approach may be justified.
BOO as the primary cause of UAB in women is uncommon, occurring in 3 % of those referred for urodynamic studies from a general population (Massey and Abrams 1988). Cases of BOO in women are probably associated with pelvic floor dysfunction/spasticity and cause such as Fowler’s syndrome (Fowler et al. 1988). Anatomical BOO in women may be iatrogenic after pelvic prolapse and anti-incontinence surgery or pelvic organ prolapse, urethral stricture, and urethral diverticula.
Association Between OAB and UAB (Fig. 1.2)
Fig. 1.2
Several ways to consider the relationship between the overactive bladder (OAB) and underactive bladder (UAB). (a) OAB and UAB as separate conditions; (b) OAB and UAB as overlapping syndromes; (c) OAB may progress to UAB (Permission obtained Chancellor 2014)
Both OAB and UAB are common in older patients.
Both are syndromes with shared symptoms including frequency and nocturia.
Both can occur together – detrusor hyperreflexia impaired contractility (DHIC).
Both are associated with common underlying etiologies – bladder outlet obstruction, neurological diseases, e.g., diabetes mellitus.
Skeletal muscle sarcopenia increases with aging, and impaired bladder emptying is also associated with increasing age in both men and women (Cucchi et al. 2008; Madersbacher et al. 1998; Malone-Lee and Wahedna 1993). It has also been established that impaired bladder emptying is often associated with detrusor overactivity with or without bladder outflow obstruction (Resnick and Yalla 1987; Elbadawi et al. 1993). Detrusor hyperreflexia impaired contractility (DHIC) is a common and important finding based on urodynamic studies in both healthy and symptomatic elderly (Ameda et al. 1999) (Fig. 1.3). Griffiths et al. (2007) noted the coincidental occurrence and overlap of OAB and UAB with different etiological factors. Histological studies including electron microscopic analysis detected age-related change in the bladder associated with both detrusor overactivity and underactivity in DHIC patients (Elbadawi et al. 1993).
