Insomnia

Overview

Insomnia is difficulty falling asleep, staying asleep, or waking too early, resulting in daytime impairment. It is classified as acute (less than 3 months) or chronic (3 months or more, at least 3 nights per week). Chronic insomnia affects thinking, mood, performance, and physical health. It is highly treatable, particularly with cognitive behavioural therapy.

How common is it?

Insomnia is common and can occur at any age. It is more likely in older adults and women, and may be short term or persist for months or longer.

Causes and risk factors

Insomnia results from hyperarousal of the central nervous system, often initially triggered by stress and then maintained by maladaptive sleep habits and beliefs.

Common risk factors

• Psychological: anxiety, depression, stress, worry about sleep itself
• Medical conditions such as pain, gastro-oesophageal reflux, asthma, heart failure and restless legs syndrome
• Sleep environment: noise, light, irregular sleep schedule
• Substances: caffeine, alcohol, nicotine, stimulant medications
• Shift work and jet lag disrupting circadian rhythm
• Medications: corticosteroids, SSRIs, some beta-blockers
• Menopause (hot flushes)
• Primary insomnia disorder with no identifiable cause

Symptoms

• Difficulty falling asleep (sleep onset latency over 30 minutes)
• Waking during the night and struggling to return to sleep
• Early morning wakening before desired time
• Non-restorative sleep
• Daytime fatigue, irritability, or mood disturbance
• Difficulty concentrating and poor memory
• Increased errors or accidents
• Preoccupation and anxiety about sleep

When to see a doctor

See a doctor if insomnia has persisted for more than 3 months, significantly affects daytime function, or may be related to an underlying medical or psychiatric condition. Always seek assessment if sleep apnoea is suspected.

Diagnosis

Primarily clinical, using sleep diary over 2 weeks. Pittsburgh Sleep Quality Index and Insomnia Severity Index are validated questionnaires. Polysomnography only if sleep-disordered breathing or parasomnias are suspected.

Treatments

Self-care and lifestyle

• Maintain consistent wake time every day, including weekends
• Avoid caffeine after noon and alcohol within 3 hours of bedtime
• Reserve the bed for sleep and sex only (not phones, laptops, or TV)
• Keep the bedroom cool, dark, and quiet
• Avoid naps during the day if struggling to sleep at night

Prevention

Good sleep hygiene from the start, managing stress actively, and avoiding caffeine and screen overuse in the hours before bed reduce the risk of chronic insomnia developing.