About Bladder Dysfunction: Neurogenic vs. Overactive

Neurogenic Bladder (NB)

Neurogenic bladder refers to bladder dysfunction caused by damage to the nervous system. It commonly occurs after spinal cord injury (SCI), and also in conditions like multiple sclerosis, spina bifida, stroke, or Parkinson’s disease (Patel et al. 2016). In SCI patients, loss of brain–bladder communication leads to problems such as detrusor overactivity (bladder spasms) and detrusor-sphincter dyssynergia (bladder and sphincter contracting simultaneously). Neurogenic bladder is highly prevalent after SCI and profoundly impacts health and quality of life (Hamid et al. 2018; Herrity et al. 2022). Patients may experience incontinence (leakage) and inefficient emptying (urinary retention), which in turn cause serious complications (Van Kerrebroeck et al. 1993; Zeilig et al. 2000):

• Recurrent infections: Urinary tract infections are frequent and can progress to life-threatening sepsis.

• Kidney damage: High bladder pressures and reflux of urine toward the kidneys (hydronephrosis) risk renal failure.

• Autonomic dysreflexia: In those with higher SCI, an overfull bladder can trigger this dangerous surge in blood pressure.

• High healthcare burden: Ongoing catheterization, medications, and complications lead to substantial treatment costs and reduced life expectancy.

Restoring bladder control is a top priority for people with SCI – surveys show that, after regaining hand function, improved bladder/bowel function is among the most desired recoveries (Anderson 2004; French et al. 2010; Bochkezanian et al. 2024). Unfortunately, standard management of neurogenic bladder relies on lifelong measures like indwelling catheters or intermittent self-catheterization and anticholinergic drugs, which manage symptoms but do not restore normal bladder function. These approaches often have high dropout rates and side effects (e.g. dry mouth, constipation), contributing to ongoing unmet needs (Benevento and Sipski 2002; Chancellor et al. 2013).

Overactive Bladder (OAB)

Overactive bladder is a common bladder disorder in the general population. It is characterized by sudden, strong urges to urinate (urgency), frequent urination (often >8 times a day), nighttime urination (nocturia), and sometimes involuntary leakage (urge incontinence) (White and Iglesia 2016; Leron et al. 2018). OAB is very prevalent – about 12% of adults are affected, including an estimated 33 million people in the USA alone (Ganz et al. 2010; Staskin et al. 2012). For many, OAB symptoms range from a frustrating nuisance to truly debilitating. The constant fear of urgency and accidents can cause anxiety, social withdrawal, shame, and even depression (Brown et al. 2000; Nygaard 2010; Milsom et al. 2012).

Despite the large number of OAB sufferers, current treatment options are often inadequate. First-line therapies like pelvic floor exercises and bladder training help some but not all. Medications (typically antimuscarinic drugs) offer only partial relief for many patients and frequently cause side effects (dry mouth, constipation, cognitive effects). As a result, adherence to OAB drugs is poor – studies show that a majority of patients discontinue medication within a year due to side effects or insufficient improvement (Nygaard 2010). This leaves a significant unmet need: millions of individuals continue to experience frequent urgency and incontinence despite available treatments (Chancellor et al. 2013; White and Iglesia 2016).

Next: Learn more about how neural stimulation works to alleviate symptoms of OAB and NB