Sleep Disorders, Insomnia & Restless Legs Syndrome

Sleep Disorders, Insomnia & Restless Legs Syndrome in Clinical Practice

Sleep architecture undergoes substantial changes across the adult lifespan, with older adults experiencing reductions in slow-wave (N3) and REM sleep, increased nocturnal awakenings, and an advanced sleep phase ("early to bed, early to rise"). However, persistent insomnia, excessive daytime sleepiness, nocturnal gasping, or involuntary leg sensations represent pathological conditions rather than normal aging. The advanced practice registered nurse (APRN) must apply evidence-based diagnostic criteria, execute non-pharmacological interventions, adhere to strict sedative prescribing warnings (Beers Criteria 2023), conduct Obstructive Sleep Apnea (OSA) screening, and perform mandatory laboratory workups for Restless Legs Syndrome (RLS).

Insomnia Disorder: Diagnostic Criteria and Evaluation

According to the DSM-5-TR, Insomnia Disorder is defined as a predominant dissatisfaction with sleep quantity or quality associated with one or more sleep disruption patterns:

1. Difficulty initiating sleep (sleep onset insomnia).
2. Difficulty maintaining sleep characterized by frequent awakenings (sleep maintenance insomnia).
3. Early-morning awakening with inability to return to sleep (late insomnia).

Diagnostic Thresholds

To meet criteria for Insomnia Disorder, the sleep disturbance must:

• Cause clinically significant distress or impairment in social, occupational, or daytime functioning.
• Occur at least 3 nights per week.
• Be present for a minimum duration of 3 months.
• Occur despite adequate opportunity for sleep.

Assessment Protocol

Clinicians should obtain a 2-week sleep diary logging bedtime, sleep latency, night awakenings, wake time, total sleep time, daytime naps, caffeine/alcohol intake, and medication timing. Secondary causes must be systematically evaluated and optimized, including GERD, nocturnal angina, heart failure, COPD, chronic pain, nocturia secondary to BPH, major depression, and offending medications (e.g., systemic corticosteroids, beta-blockers, SSRIs, decongestants, or late-day diuretics).

Non-Pharmacological Management: CBT-I and Sleep Hygiene

Cognitive Behavioral Therapy for Insomnia (CBT-I) is the first-line, gold-standard treatment for chronic insomnia disorder, demonstrating superior long-term efficacy compared to hypnotic pharmacotherapy.

Core Components of CBT-I

1. Stimulus Control Therapy: Re-establishes the association between bed and sleep:
   • Go to bed only when feeling sleepy.
   • Use the bed and bedroom only for sleep and sexual intimacy (no reading, TV, work, or smartphone use in bed).
   • If unable to fall asleep or return to sleep within 15 to 20 minutes, get out of bed, move to another dimly lit room, engage in a quiet activity (reading a physical book), and return to bed only when sleepy.
   • Maintain a fixed wake-up time every morning 7 days a week.
   • Avoid daytime naps (or limit to < 30 minutes before 3:00 PM).
2. Sleep Restriction Therapy: Restricts time in bed to equal reported total sleep time (minimum baseline 5 hours), consolidating sleep drive. As sleep efficiency (Total Sleep Time / Time in Bed x 100%) exceeds 85%, time in bed is increased by 15 to 30 minutes.
3. Cognitive Restructuring: Addresses catastrophic beliefs regarding sleep loss.
4. Sleep Hygiene Education: Maintain a cool (65–68°F), dark, quiet bedroom; avoid heavy meals within 2–3 hours of bedtime; avoid alcohol near bedtime (causes REM suppression and sleep fragmentation); discontinue caffeine at least 6 hours prior to bedtime; avoid screen exposure 1–2 hours before bed.

Pharmacotherapy and Beers Criteria 2023 Warnings

High-Risk Sedatives in Older Adults

The American Geriatrics Society Beers Criteria 2023 warns against traditional hypnotics in older adults (aged >= 65):

• Benzodiazepines (Temazepam, Triazolam, Diazepam, Lorazepam): Associated with double the risk of motor vehicle accidents, falls, hip fractures, cognitive impairment, delirium, dependence, and withdrawal.
• Non-Benzodiazepine Receptor Agonists ("Z-drugs": Zolpidem, Eszopiclone, Zaleplon): Carry comparable severe risks of falls, fractures, delirium, and dangerous complex sleep behaviors (sleep-walking, sleep-driving while not fully awake). Avoid in older adults.
• Over-the-Counter Antihistamines (Diphenhydramine, Doxylamine): Highly anticholinergic; cause acute confusion, delirium, urinary retention, dry mouth, constipation, blurred vision, and fall risk. Avoid in older adults.

Safer Pharmacological Alternatives (When CBT-I is Insufficient)

• Ramelteon (Rozerem): Selective melatonin MT1 and MT2 receptor agonist. Non-controlled, carries no GABA activity or fall risk. Safe in older adults for sleep-onset insomnia.
• Low-Dose Doxepin (Silenor 3 mg or 6 mg): At low doses (3–6 mg), doxepin acts purely as a selective histamine H1 receptor antagonist without significant anticholinergic activity. Indicated for sleep maintenance insomnia in older adults.
• Dual Orexin Receptor Antagonists (DORAs: Suvorexant, Lemborexant): Block wake-promoting orexin neuropeptides. Effective for onset and maintenance insomnia.

Obstructive Sleep Apnea (OSA)

Obstructive Sleep Apnea (OSA) involves recurrent collapse of the pharyngeal airway during sleep, causing apneas (airflow cessation >= 10 seconds), hypopneas, nocturnal hypoxemia, sympathetic surges, and sleep fragmentation. Uncontrolled OSA is a risk factor for resistant hypertension, atrial fibrillation, stroke, nocturnal MI, and vascular dementia.

Screening with the STOP-BANG Questionnaire

• Snoring (loud)
• Tired (daytime fatigue/sleepiness)
• Observed apneas/gasping
• Pressure (Hypertension)
• BMI > 35 kg/m2
• Age > 50 years
• Neck Circumference > 16 inches (females) or > 17 inches (males)
• Gender male

Interpretation: Scores 0–2 = Low risk; 3–4 = Intermediate risk; 5–8 = High risk for moderate-to-severe OSA.

Diagnosis and Management

• Polysomnography (PSG): In-lab or home sleep apnea test (HSAT) is mandatory. Measured by Apnea-Hypopnea Index (AHI): Normal < 5, Mild 5–14, Moderate 15–29, Severe >= 30 events/hour.
• Treatment: Continuous Positive Airway Pressure (CPAP) is gold-standard therapy. Monitor adherence (minimum 4 hours/night on 70% of nights), counsel on weight loss, avoid sedatives/alcohol, and consider oral appliances.

Restless Legs Syndrome (RLS) / Willis-Ekbom Disease

RLS is a sensorimotor disorder characterized by an irresistible urge to move the legs, accompanied by uncomfortable paresthesias ("crawling", "pulling"). Symptoms follow the URGE criteria:

• Urge to move legs with uncomfortable limb sensations.
• Rest or inactivity triggers or worsens symptoms.
• Getting up or moving (walking, stretching) provides relief.
• Evening or night onset or peak worsening.

Mandatory Iron Workup Protocol

Central nervous system iron deficiency in the substantia nigra impairs dopaminergic signaling. Serum Ferritin and TIBC must be checked in all RLS patients.

• Iron Threshold: If serum ferritin is < 50 mcg/L (or transferrin saturation < 20%), oral iron supplementation (Ferrous Sulfate 325 mg with Vitamin C 500 mg) is first-line therapy. Target ferritin level is > 75 to 100 mcg/L.

Pharmacotherapy Guidelines

• First-Line Pharmacotherapy: Alpha-2-Delta Calcium Channel Ligands (Gabapentin enacarbil 600 mg daily, Gabapentin 300–900 mg before bedtime, or Pregabalin 75–150 mg). Highly effective, non-dopaminergic, and avoids augmentation.
• Dopamine Agonists Warning (Pramipexole, Ropinirole): Now second-line due to Augmentation—a progressive paradoxical worsening of RLS where symptoms appear earlier in the day, spread to arms, and become more intense. If augmentation occurs, dopamine agonists must be slowly tapered off.