What treatment approach is suitable for an elderly patient with overactive bladder (OAB), potential glaucoma, and slow digestion?

Treatment Approach for Elderly Patient with OAB, Potential Glaucoma, and Slow Digestion

In this elderly patient with overactive bladder, potential glaucoma, and slow digestion (impaired gastric emptying), antimuscarinic medications should be avoided, and you should instead offer beta-3 agonist therapy (mirabegron) as first-line pharmacologic treatment, or proceed directly to minimally invasive therapies such as sacral neuromodulation, tibial nerve stimulation, or botulinum toxin injection. 1

Why Antimuscarinics Are Contraindicated in This Patient

Antimuscarinics must be used with extreme caution—or avoided entirely—in patients with narrow-angle glaucoma and impaired gastric emptying. 1 The most recent 2024 AUA/SUFU guidelines explicitly state that antimuscarinic medications should be used with extreme caution in patients with narrow-angle glaucoma and impaired gastric emptying (slow digestion). 1

Specific Contraindications Present:

• Potential glaucoma: Antimuscarinics are contraindicated in narrow-angle glaucoma unless approved by the treating ophthalmologist. 1 Given the uncertainty about glaucoma type in this patient, ophthalmology clearance would be mandatory before any antimuscarinic use.

• Slow digestion (impaired gastric emptying): The guidelines specifically warn that patients at risk for gastric emptying problems should receive clearance from a gastroenterologist prior to antimuscarinic initiation. 1 Additional conditions that impact gastric emptying include diabetes, prior abdominal surgery, narcotic use, scleroderma, hypothyroidism, Parkinson's disease, and multiple sclerosis. 1

• Elderly status: In frail elderly patients with mobility deficits, weight loss, weakness, or cognitive deficits, OAB medications have a lower therapeutic index and higher adverse event profile. 1 Antimuscarinics are associated with increased risk of dementia and cognitive impairment, which may be cumulative and dose-dependent. 1

Recommended Treatment Algorithm

First-Line: Behavioral Therapies (Always Start Here)

Begin with behavioral interventions, which are as effective as antimuscarinic medications for reducing symptoms and have no adverse effects. 1

• Bladder training and delayed voiding: Modifies bladder symptoms by changing voiding habits. 1
• Pelvic floor muscle training: Improves control and urge suppression techniques. 1
• Fluid management: A 25% reduction in fluid intake reduced frequency and urgency. 1
• Caffeine reduction: Resulted in reductions in voiding frequency. 1
• Weight loss if obese: An 8% weight loss in obese women reduced urgency urinary incontinence episodes by 42%. 1

Second-Line: Beta-3 Agonist (Mirabegron)

If behavioral therapy alone is insufficient, offer mirabegron (beta-3 agonist) as the preferred pharmacologic option. 2

• Mirabegron has comparable efficacy to antimuscarinics with significantly lower incidence of anticholinergic side effects. 2
• It has reduced risk of cognitive effects compared to antimuscarinics. 2
• It does not worsen gastric emptying or glaucoma. 2
• The 2024 guidelines note that a trial of beta-3 agonists is typically preferred before antimuscarinic medications. 1

Third-Line: Minimally Invasive Therapies

The 2024 AUA/SUFU guidelines now support offering minimally invasive therapies without requiring trials of pharmacologic management in the context of shared decision-making. 1

Given this patient's multiple contraindications to antimuscarinics, you may offer:

• Sacral neuromodulation (SNM): FDA-approved, shows improvement in all measured parameters including quality of life, with durable treatment effects. 1, 3 However, >30% of patients require additional surgeries for device-related issues. 3

• Tibial nerve stimulation (PTNS): Effective in reducing voiding frequency, nocturia, urgency episodes, and incontinence episodes. 1 Requires repeated in-office treatments (30 minutes once weekly for 12 weeks). 1

• Intradetrusor botulinum toxin (100 U): Grade A evidence for efficacy. 1 Patient must be able and willing to return for frequent post-void residual evaluation and perform self-catheterization if necessary. 1

Critical Pitfalls to Avoid

• Do not prescribe antimuscarinics without ophthalmology clearance for the potential glaucoma and gastroenterology clearance for impaired gastric emptying. 1

• Do not ignore the dementia risk in elderly patients taking antimuscarinics—a meta-analysis found association with increased risk of all-cause dementia and Alzheimer's disease. 1

• Do not assume all elderly patients are too frail for minimally invasive therapies—these options have high success rates, durable efficacy, and excellent patient satisfaction. 1

• Avoid polypharmacy complications: Antimuscarinics metabolized by CYP450 (oxybutynin, tolterodine, darifenacin, solifenacin) have potential for drug interactions in elderly patients on multiple medications. 4

If Antimuscarinics Are Absolutely Necessary

Should specialist clearance be obtained and antimuscarinics deemed necessary:

• Trospium chloride may be the safest option as it is not extensively metabolized by CYP450, is excreted largely unchanged in urine, and has not been associated with cognitive adverse events or sleep disturbances. 4

• Monitor closely for constipation (which would worsen slow digestion), urinary retention, and cognitive changes. 2

• Check post-void residual before initiating therapy to assess urinary retention risk. 1, 2