What Is Enuresis
Enuresis is involuntary urination during sleep, commonly called bedwetting. In children, it's normal up to age 5 or 6. Primary nocturnal enuresis (never achieved consistent dryness) affects about 15-20% of 5-year-olds and 5% of 10-year-olds. Secondary nocturnal enuresis (bedwetting after at least 6 months of dryness) often signals an underlying sleep or medical issue that warrants evaluation.
Enuresis differs from other parasomnias because it involves loss of bladder control rather than abnormal behavior during sleep. The mechanism involves a combination of factors: deep sleep arousal thresholds, nocturnal polyuria (excessive nighttime urine production), and reduced bladder capacity. Many children with enuresis spend more time in deep sleep stages and don't wake to the sensation of a full bladder.
Types and Causes
- Primary nocturnal enuresis: Never achieved nighttime dryness. Often genetic; if both parents had enuresis, risk is 77%. Usually resolves by age 15-18.
- Secondary nocturnal enuresis: Regressed after dryness. May indicate sleep apnea, constipation, urinary tract infection, diabetes, or psychological stress. Requires medical workup.
- Sleep architecture role: Polysomnography studies show enuretic children have higher arousal thresholds and spend more time in stage 3 (deep) sleep. They fail to wake when bladder pressure increases.
- Circadian factors: Abnormal melatonin and arginine vasopressin (AVP) patterns disrupt the normal nighttime reduction in urine production. This is why desmopressin (synthetic AVP) works as first-line pharmacological treatment.
Management Approaches
Treatment depends on age, frequency, and whether primary or secondary. For primary enuresis in children under 7, watchful waiting is appropriate. After age 7, interventions include:
- Behavioral methods: Fluid restriction 2 hours before bed, scheduled bathroom trips, moisture alarms (most effective for motivated families). Success rates reach 60-70% with alarms used consistently.
- Sleep hygiene optimization: Regular sleep schedule, adequate sleep duration (children need 8-10 hours), and avoiding sleep deprivation. Poor sleep increases arousal thresholds.
- Desmopressin therapy: Tablets or melt formulations reduce nighttime urine production. Effective in 50-60% of cases but doesn't address underlying arousal problem; relapse is common after stopping.
- Ruling out sleep disorders: If enuresis persists despite treatment or appears suddenly after dryness, polysomnography may identify obstructive sleep apnea or periodic leg movements.
- Addressing comorbidities: Treat constipation (strongly associated), screen for diabetes or urinary issues, and evaluate for anxiety or depression.
Common Questions
- When should we evaluate bedwetting? Seek evaluation after age 7 if occurring more than twice weekly, or any time it's secondary (child was dry then regressed). Also evaluate if a child has daytime accidents, which raises concern for sleep apnea or neurological issues.
- Can sleep apnea cause enuresis? Yes. Obstructive sleep apnea disrupts normal sleep architecture and oxygen levels, impairing arousal and bladder control. Treatment of the apnea often resolves enuresis without additional intervention.
- Does CBT-I help with enuresis? Cognitive behavioral therapy for insomnia focuses on sleep quality and circadian timing. While not a direct treatment, optimizing sleep schedule and reducing sleep anxiety can help, especially if poor sleep is worsening arousal thresholds.