Introduction

Urinary incontinence (UI) is the complaint of involuntary loss of urine [1•]. Prevalence increases with age, making it a considerable public health concern for the elderly, given the forecasted population growth among those over 65 years [2, 3]. The impact of UI on health-related quality of life is substantial, and is associated with comorbid conditions, institutionalization and mortality [4].

The most common type of UI to affect both elderly men and women is urgency urinary incontinence (UUI), the complaint of involuntary loss of urine associated with sudden, compelling desire to pass urine which is difficult to defer [1•]. Other types of UI reported by older men and women include nocturnal enuresis, continuous incontinence, or insensible urinary incontinence when the patient is unaware of how UI occurred [1•]. Stress urinary incontinence (SUI), the complaint of involuntary loss of urine on effort or physical exertion (sporting activities), or on sneezing or coughing, and mixed urinary incontinence (MUI), the complaint of both UUI and SUI, predominately affects women [1•]. UUI and MUI are often accompanied by symptoms of overactive bladder (OAB), including urinary frequency, urgency, and nocturia. Post-prostatectomy UI in men can range from 5–60 %, depending on the definition of UI used and the type of treatment administered, but has been decreasing in contemporary studies with improved understanding of prostatic anatomy, surgical technique and localization of applied therapies [5]. UI does improve within the first year following prostate treatment, so understanding natural history of the healing process is important in planning interim therapy [6•].

Severity of UI in the elderly can wax and wane, and may be depended on exacerbations of concomitant disease processes, medications and proximity to ancillary procedures or treatments. The aim of this update is to review newly published data to guide clinicians in diagnosis and treatment of UI in the elderly patient.

Diagnosis

The specific type of UI can generally be elicited by thorough history and physical exam, with complex clinical scenarios requiring urodynamic testing for definitive diagnosis.

The review of systems should screen for other conditions that may make the patient’s treatment more complex. For men with pain, hematuria, recurrent infections, suspected or proven incomplete bladder emptying, or incontinence following pelvic irradiation, specialty evaluation is recommended. Additional factors in women prompting further evaluation include significant pelvic organ prolapse, persistent incontinence or recurrent incontinence after previous incontinence surgery, history of pelvic irradiation, prior radical pelvic surgery, and suspected fistula [7••].

The examination for UI is best performed with the patient’s bladder comfortably full to observe the involuntary loss of urine, either urethral or extraurethral. Observation of involuntary leakage from urethra on coughing or valsalva is strongly suggestive of SUI, whereas the observation of involuntary leakage from the urethra with the sensation of a sudden, compelling desire to void that is difficult to defer is highly suggestive of UUI [1•]. Extraurethral incontinence, highly suggestive of a genitourinary fistula, is the observation of urine leakage through channels other than the urethral meatus. In addition to a directed exam trying to elicit UI, the innervation of the sacral nerve roots (S2-S4) should be evaluated and more generalized neurologic exam should be performed as indicated. The abdominal exam should explore signs of bladder fullness, the presence of other abdominal masses or ascites, and scars indicating previous relevant surgery or trauma. The flank area should be examined to assess for renal tenderness and masses.

A detailed pelvic exam should be performed in the female patient, evaluating the presence of atrophic vaginitis, hypermobility of anterior vaginal wall, and prolapse of pelvic organs. The urethra should be evaluated for erosion in patients who have had prolonged indwelling catheters, and to rule out abnormalities including urethral diverticuli. In both sexes, a rectal exam should be performed to evaluate anal sphincter tone, the presence of masses, the presence or absence of fecal impaction, and the size and nodularity of the prostate in male patients. The pelvic floor muscles should be evaluated at baseline and with a voluntary or reflex contraction, to determine if the response is strong, normal, weak, or absent.

Initial office evaluation should include post-void residual measurement, urine analysis, microscopy, and urine culture with sensitivity if indicated. Additional evaluation that may be helpful in diagnosis and management of UI includes a 24–48 hour bladder diary, where a patient records the time of each micturition, the volume of each void, fluid intake, pad usage, number and severity of incontinence episodes for at least 24 hours. The use of patient self-reported questionnaires, such as the International Consultation on Incontinence Questionnaire (ICIQ) [8] or urodynamics, can be helpful to clarify the type of UI if it is still unclear after a thorough history and physical exam.

Treatment

When initiating treatment for UI in older patients, several factors need to be considered. A patient’s comorbidities, current medication use, life expectancy, preferences for care, and goals of care (both for the patient and potential caregivers) should be considered when choosing therapy, especially in frail elderly patients with UI [9••].

The following reversible causes of UI should be investigated in each individual patient and treated if found: delirium, urinary tract infection, polyuria, restricted mobility and fecal impaction. Medications such as diuretics, antidepressants, anti-psychotics, α-blockers, and α-agonists have all been shown to cause or exacerbate urinary incontinence, and should be evaluated to determine whether alternate medications could be used to decrease UI [10].

Behavioral Modification

Behavioral modifications such as caffeine restriction, fluid manipulation if patients have excessive fluid intake, and bladder retraining through timed voiding are beneficial first line treatments for UI [11]. Fluid restriction should be avoided in long-term care residents and other frail elders who may not have ready access to fluids or accurately sense thirst [9••]. Timed voiding and habit training are particularly important aspects of treatment for nursing home residents [9••]. For obese women, weight loss is helpful in conjunction with exercise and behavioral modification to decrease UI [12]. Adding pelvic floor muscle exercises to behavioral therapy resulted in significant decreases in OAB symptoms [13]. Combinations of behavioral treatments are more effective than just one [14]. In a recent Cochrane review [15], UUI symptom improvement is greater when behavioral modification is combined with an antimuscarinic than either therapy alone.

Physiotherapy Treatment

Pelvic Floor Muscle Training

Pelvic floor muscle training (PMFT) has been prescribed for over 60 years to improve both SUI and UUI. PMFT require tightening of the pelvic muscles and holding the contraction for a few seconds, followed by a rest period. PMFT may prevent urgency and UUI by inhibiting and aborting inappropriate detrusor contractions [16], while stimulating the guarding reflex in adults with SUI [17].

Dumoulin and Hay-Smith [18••] concluded in their Cochrane review that PFMT should be included in first-line conservative management programs for women with SUI, UUI or MUI. The treatment effect seemed to be greater in women with SUI alone, who participated in a supervised PFMT program for at least 3 months.

A recent Cohrane review [19••] evaluated the impact of PFMT with or without biofeedback for men who had urinary incontinence after radical prostatectomy. Findings were conflicting; limited benefit was seen in improving UI in studies that aimed at both treatment and prevention.

Biofeedback

Pelvic floor biofeedback uses surface perineal electrodes or vaginal or rectal cones to monitor external urinary sphincter or levator ani muscle activity during PMFT. Biofeedback provides the patient and the practitioner with visible cues indicating proper isolation and contraction of the muscle group being exercised. Biofeedback may be more effective than placebo or PFMT in reducing UI [20, 21••].

Electrical Stimulation

Vaginal electrical stimulation has been used in the treatment of both SUI and UUI. There is considerable variation in devices, electrical parameters and recommended frequency of treatment [22, 23]. Data on efficacy is conflicting [22–25], and a significant placebo effect may exist.

Vaginal Cones

In a randomized controlled trial, vaginal cone therapy showed no increased benefit above PFMT for the treatment of postmenopausal SUI [26].

Medications

There are currently no FDA approved medications for SUI in the United States. Imipramine and duloxetine have been studied as off-label therapies for SUI, but should not be used in elderly patients [9••].

Pharmacologic Therapies for UUI

Antimuscarinics

Antimuscarinic medications, which act on the filling-storage phase by inhibiting afferent input from the bladder and directly inhibiting smooth muscle contractility, are the most commonly used pharmacotherapy for UUI when conservative treatment is inadequate to control symptoms [15]. The efficacy of tricyclic antidepressants, α-adrenergic agonists, afferent nerve inhibitors, prostaglandin antagonists, β-adrenergic agonists, and calcium channel blockers versus antimuscarinics for UUI has not been compared in well designed randomized clinical trials. These medications are used sparingly [27].

Common side effects from antimuscarinic medications include dry mouth, blurred vision, confusion, constipation [28] and rarely increased heart rate[29] as muscarinic receptors are also present in other body tissues. Discontinuation rates have been reported as high as 71 % [30].

Oxybutynin, tolterodine, trospium, solifenacin, darifenacin, and festoterodine are the antimuscarinic medications currently available in the United States. Table 1 summarizes each medication, dosage and elderly-specific information (Table 1). In a recent meta-analysis of the adverse event profiles for antimuscarinics, the profiles for darifenacin, festoterodine, transdermal oxybutinin, solifenacin, tolterodine and tropsium chloride are similar though oral oxybutynin had a higher rate of dry mouth and constipation. The most common reported adverse event was dry mouth [32].

Table 1 Dose, adverse reactions*, and elderly-specific data on antimuscarinic medications
Full size table

Although drug absorption does not differ with age, drug distribution may change due to decreased muscle mass, decreased water content, and renal impairment. The blood-brain barrier may be more permeable in elderly patients secondary to comorbidities and other medications, increasing the rate of central nervous system side effects [33•]. There are relatively little data on the central nervous system safety in the elderly [33•, 34••], and prior clinical trials have not adequately screened, measured, and documented CNS symptoms [34••].

In the few trials reporting specifically on the efficacy of antimuscarinic medications in elderly populations, healthy older patients seem to have similar efficacy without an increase in serious adverse effects or side effect profiles when compared with younger women [35–37]. Some studies however suggest that antimuscarinics may be effective at lower doses in frail older persons due to pharmacokinetic changes associated with aging [9••]. Close monitoring is needed when prescribing these medications to older patients, and unlike in younger patients, combinations of bladder antimuscarinics should not be used [9••]. Furthermore, physicians should be aware of the additive antimuscarinic effect of medications used to treat Parkinson’s disease or dementia when treating patients with UUI.

Some recent studies of antimuscarinics in elderly subjects are worth mentioning.

Lackner et al. [38•] recently published results of a randomized controlled trial of the efficacy of oral extended-release oxybutynin in cognitively impaired older women with UUI in a nursing home setting. In the absence of a behavior training program, oxybutynin had no increased benefit over placebo regardless of cognitive or functional status. However, there was also no worsening of cognitive status or other significant differences in the safety profiles in this 4-week trial.

In a database study looking a claims data, tolterodine was continued for almost twice as long compared to oxybutynin in elderly patients although less that half of patients continued therapy in either group 6 months after initiating treatment [39]. In a study of a health care claims database, there was no significant difference in falls, hospital visits for fracture or delirium in the first 90 days after elderly patients initiated either tolterodine or oxybutynin. There was a slight increased risk in hospitalization for any cause or death for any cause in the oxybutynin group. As outcomes were exploratory in nature and effect sizes were relatively small, the authors recommended interpreting these findings with caution [40].

In a recent sub-analysis [41], there was no significant difference in the tolerability of solifenancin and oxybutynin immediate-release between older (> 65 years) and younger (≤ 65 years) patients.

Recent large studies [42, 43] have reported that fesoterodine 8 mg was superior to extended-release tolterodine 4 mg for UUI episodes and other outcomes as early as 3 weeks and have also now demonstrated the continued efficacy and tolerability of this drug for 24 months regardless of age [44, 45].

β-3 Agonists

A β-3 agonist, mirabegron [46], is available for use in Japan and has recently been approved by the FDA for use in the United States. This drug stimulates the β-3 adrenergic receptors, the predominate receptors of the detrusor muscle [47], to improve relaxation during the storage phase of micturition [47]. Early results show mirabegron to be more effective than placebo in treating OAB [48, 49]. Common antimuscarinic side effects were reported less frequently for individuals receiving mirabegron than with tolterodine extended-release but dizziness and palpatations were slightly higher. No increase in cardiovascular adverse events in the short-term studies completed thus far has been noted, although small significant changes in blood pressure and heart rate were seen. Long-term safety data, especially in elderly patients, are needed [46, 50].

Botulinum-A Toxin

Injection of botulinum toxin into the detrusor muscle is approved by the FDA for the treatment of neurogenic OAB. Botulinum toxin(BoNT/A) is a potent neurotoxic protein that inhibits detrusor contractions are inhibited by blocking the release of achetylcholine and other neurotransmitters [51]. BoNT/A may also decrease sensory input to the bladder by down-regulating the receptors of afferent neurons in the detrusor muscle [52]. Commonly, under local anesthesia with cystoscopic guidance, 100–200 units of BoNT/A is delivered via multiple injections into the detrusor muscle or submucosa of the bladder, sparing the trigone. To maintain efficacy, injections may need to be repeated every 3–12 months. Procedural risks include gross hematuria (≤ 10 %) [53], urinary tract infection (≤ 22 %) [53], pain, and increased post-void residual requiring de novo intermittent self-catheterization [54••]. Transient and mild neurologic side effects (≤ 10 %) have also been reported [55]. Rare systemic side effects such as diffuse muscle weakness have also been reported (1 %) [56] and usually resolve within a few months.

Although BoNT/A can improve symptoms of OAB, a Cochrane review [57] concluded that too little data exist on safety and efficacy compared with placebo and other treatments. BoNT/A injections have been showed to be significantly more successful in patients with anticholinergic intolerability, as compared to patients with poor medication efficacy [58]. In a phase 2 double-blind, randomized trial [59] comparing a single dose (100 units or 150 units) of BoNT/A to placebo in adults with refractory OAB, up to 65 % of patients had more than 50 % improvement with BoNT/A, with minimal rates of urinary tract infection and urinary retention. In a randomized trial of BoNT/A injection versus oral anticholinergic medication in women with idiopathic UUI who were not refractory to treatment, Visco et al. [60••] reported similar efficacy in reduction of UUI episodes (3.4 in the anticholinergic group and 3.3 in the BoNT/A group, p = 0.81) and quality of life improvement. However, the reported dry rate in the BoNT/A group (27 %) was twice the dry rate of the anticholinergic group (13 %, p = 0.003). The BoNT/A group was less likely to have dry mouth, but had higher rates of transient urinary retention and urinary tract infections. A clear consensus on the use of the drug in clinical practice including optimal dose, location and number and timing of initial and repeat injections, has not been determined. No trials of BoNT/A specifically address the elderly. Special concerns regarding the use of BoNT/A in the elderly include increased risk of post-procedure urinary retention due to impaired bladder contractility and reduced dexterity and ability to perform clean intermittent self-catheterization. Although Allergan is seeking FDA approval for a 100 unit BoTN/A dose for idiopathic OAB, currently its use is off-label and should be restricted to patients who have failed conservative therapies [61].

Estrogen

Loss of estrogen on urogential tissue, including thinning of mucosa, loss of sphincter muscle tone, and alteration of the urethrovesical angle, may contribute to the increased prevalence of OAB in postmenopausal women [62]. Vaginal estrogen improves symptoms of urgency and frequency in postmenopausal women, but neither vaginal nor oral estrogen has been shown to be effective for UUI [63–66].

α -Adrenergic Blockers

Several randomized trials have shown that in elderly men with benign prostatic hyperplasia being treated with an α-blocker, the addition of an anticholingeric can improve persistent OAB symptoms with minimal side effects [67–69].

Neuromodulation

A second-line therapy for UUI involves neuromodulation of the nerves supplying the detrusor and pelvic floor muscles, after a patient has failed behavioral and pharmacologic interventions.

Peripheral Nerve Stimulation

Percutaneous tibial nerve stimulation (PTNS) that delivers neuromodulation to the pelvic floor via the posterior tibial nerve is a potentially promising treatment for the elderly with UUI. A fine needle electrode is inserted slightly above the ankle to access the tibial nerve. This anatomical area has projections to the S2-S4 junction of the sacral nerve plexus, creating a feedback loop that modulates bladder innervation [70, 71].

PTNS significantly decreases severity of UUI and improves health-related quality of life when compared to placebo [72, 73]. In a recent meta-analysis [74•], the short-term efficacy of PTNS was comparable to drug therapy for OAB and UUI. The effects of 12 weekly 30-minute intervention sessions are usually reported; however, patients with improvement may continue treatment at individually based greater intervals for sustained symptom relief. Studies specifically evaluating the effectiveness of PTNS in treating older adults with UUI are lacking.

Sacral Neuromodulation

Chronic stimulation of the S3 sacral nerve root via sacral neuromodulation (SNM) affects the reflexes between the detrusor, urethral sphincter, and pelvic floor muscles [75]. Chronic neuromodulation therapy requires that an electrode is placed alongside a sacral nerve (usually S3) via the sacral foramen and is connected by cables under the skin to an implanted programmable pulse generator. Implantation of the pulse generator is usually carried out only after a successful trial of either a percutaneous (skin surface) nerve evaluation or Stage I procedure [76]. In a successful trial of SNM, patients should have responded with at least a 50 % improvement in target symptoms for at least 3 days [77]. Several studies [78–80] have shown clinical utility of this therapy in older adults, but the overall paucity of high-quality prospective data on SNM use in elderly patients indicates that continued research is necessary [81•]. Pain at the implant site (25 %), lead migration (16 %), wound problems (7 %), adverse effect on bowel function (6 %), infection (5 %), and generator problems (5 %) are common complications. Up to 33 % of patients have required surgical revision of the SNM implant [82].

Magnetic Therapy

Uninhibited detrusor contractions can be suppressed through magnetic stimulation of the sacral nerve roots [83, 84]. While two prior randomized controlled trials [83, 85] showed significant improvement in symptoms of UUI for the magnetic stimulation group compared sham stimulation, a more recent study in elderly women [86] did not find significant difference compared to placebo.

Mechanical Devices

Several different mechanical devices have been investigated to improve continence. In women, vaginal pessaries or intraurethral plugs may have benefit for individual patients; pessaries need to be managed appropriately to minimize erosion risks, while urethral plugs can increase urinary tract infection rates. A Cochrane review [87••] reported little evidence from controlled trials to judge whether the use of a mechanical device is better than no treatment for the improvement of UI. There was also insufficient evidence to recommend one device over another, or comparing mechanical devices with other treatments.

In men, the penile clamp (Cunningham clamp) can be used to maintain urethral compression. This clamp latches on over the mid shaft of the penis to maintain compression and is often used after radical prostatectomy [88]. Patients are instructed to use up to 2 hours at a time during the day and to leave off at night. Clinicians should confirm that men have the manual dexterity to open and close the clamp and are cognitively intact prior to recommending this therapy [89].

Surgical Treatment

While data regarding surgical treatment in healthy older adults is increasing, very little remains know about surgical treatment of UI in frail elderly patients [9••]. Morbidity and mortality of UI surgery appear to be similar to major noncardiac surgical procedures [90]. In contrast to younger patients, urodynamics should be performed before considering anti-incontinence surgery in elderly patients [9••].

Periurethral Bulking Agents

Urethral bulking agents are suitable for patients with moderate SUI due to intrinsic sphincter deficiency [7••] or for patients where the risks of a midurethral sling would be considered too great. The effect of bulking agents decreases with time, and repeat injections may be needed to maintain effectiveness. Initial rates of improvement using collagen range from 60-80 % at 1–3 months, but decrease to 50 % at 2 years [91]. Initial improvement rates of 85 % are maintained at 2 years with polydimethylsiloxane [92]. Outcomes seem to be unrelated to age [90]. Use of this therapy is less successful for male SUI, showing only modest success rates and low cure rates [93]. Currently FDA-approved agents in the United States include autologous fat, bovine collagen, calcium hydroxylapatite, carbon beads, and polydimethylsiloxane [50].

Slings

Midurethral slings are the most common surgical option offered to treat SUI. Initial short-term data did not show significantly different success rates when comparing elderly women to younger women [94]. More recently, limited evidence suggests that older women may have lower success rates than younger women after the same length of follow-up postoperatively [95]. However, in this cohort, the older women had higher parity and were more likely to have had prior hysterectomy or anti-incontinence surgery potentially confounding the results. The sample size was too small to perform multivariable analysis to assess the impact of these factors on the success rates.

Autologous pubovaginal slings and Burch colposuspension have been used for many years to treat SUI, and may become popular once again for women unwilling to have synthetic mesh used during their reconstructive procedure. While the pubovaginal sling has a higher cure rate, it is also associated with more postoperative urinary tract infections, UUI and voiding dysfunction than the Burch colposuspension [96].

Male slings can be used to treat mild to moderate SUI in men with variable success [6•]. They have gained popularity as they do not require manual manipulation to void. Several authors [97] report very high success rates, but this has not been replicated universally.

Artificial Urethral Sphincters

Artificial urethral sphincter is the gold standard for surgical treatment of male SUI [6•]. Success rates for bringing high grade incontinence down to one pad per day or less are excellent. Satisfaction rates are also extremely high. Complication rates are low and mechanical failure is uncommon prior to 10 years [6•].

Novel Treatments

Other therapies showing early promise include intrasphincteric autologous myoblast injections in combination with VES for SUI [98], and individualized physical therapy in elderly patients to improve independence in Activities of Daily Living to decrease UI [99••]

Conclusion

The prevalence of UI is increasing as the population ages. While many therapies ranging from behavioral and physical therapy modalities to medications and surgical interventions have shown benefit in elderly populations, the data for individual modalities remain limited. Treatment of UI in the elderly should consider the natural history of UI for that specific patient population, comorbid conditions, polypharmacy and treatment goals. More research is needed looking specifically at the efficacy and safety of interventions in the geriatric patient.