Recommended Diagnostic Testing
For this patient with chronic insomnia, the essential next steps are: (1) a two-week sleep diary, (2) completion of the Epworth Sleepiness Scale, and (3) a focused psychiatric/medical questionnaire to identify comorbid conditions. 1 Additional laboratory testing beyond the previous TSH is not routinely indicated unless specific comorbidities are suspected.
Core Diagnostic Approach
The American Academy of Sleep Medicine guidelines are clear that insomnia is primarily a clinical diagnosis that does not require routine laboratory testing or polysomnography 1. The evaluation centers on structured clinical tools rather than blood work or imaging.
Required Assessment Tools
At minimum, this patient should complete:
- Two-week sleep log: Documents sleep-wake patterns, sleep onset latency, nocturnal awakenings, total sleep time, and day-to-day variability 1
- Epworth Sleepiness Scale: Identifies whether excessive daytime sleepiness is present, which would suggest alternative diagnoses like sleep apnea 1
- Medical/psychiatric questionnaire: Screens for depression, anxiety, and other comorbid conditions that commonly accompany insomnia 1
When Laboratory Testing IS Indicated
Other laboratory testing (blood work, imaging) is NOT indicated for routine chronic insomnia evaluation unless there is clinical suspicion for specific comorbid disorders 1. The TSH from one year ago is sufficient unless new symptoms suggest thyroid dysfunction (weight changes, temperature intolerance, etc.).
Critical Red Flags Requiring Polysomnography
While polysomnography is not indicated for routine insomnia evaluation 1, it becomes necessary when:
- Clinical suspicion of sleep apnea exists (snoring, witnessed apneas, gasping—though she doesn't know if she snores, consider bed partner interview) 1
- Suspected periodic limb movement disorder or restless legs syndrome 1
- Treatment failure after appropriate behavioral or pharmacologic interventions 1
- Violent or injurious behaviors during sleep 1
Important Consideration: Bed Partner Interview
Obtain history from a bed partner if possible 2. Since she doesn't know if she snores, a bed partner can provide crucial information about witnessed apneas, snoring patterns, or leg movements that would change the diagnostic approach entirely.
Behavioral Factor Assessment
Her evening exercise at 8 PM warrants specific attention. The sleep history should detail:
- Pre-sleep conditions and routines
- Timing of exercise, meals, caffeine, and alcohol
- Sleep environment factors
- Work schedules and circadian patterns 1
Late evening exercise can be stimulating and may contribute to sleep-onset difficulties, representing a modifiable behavioral factor.
Common Pitfalls to Avoid
Don't order extensive metabolic panels or repeat TSH without specific clinical indications—this wastes resources and doesn't change management 1
Don't skip the sleep diary—it's the single most valuable tool for characterizing insomnia patterns and monitoring treatment response 1
Don't assume insomnia is "just stress" without screening for depression, anxiety, and other psychiatric comorbidities that require concurrent treatment 1
Don't order polysomnography reflexively—it's specifically NOT recommended for routine insomnia and should be reserved for suspected alternative sleep disorders 1
Next Steps After Assessment
Once these clinical tools are completed, the diagnosis can be confirmed and cognitive behavioral therapy for insomnia (CBT-I) should be initiated as first-line treatment 3. The sleep diary will also serve as a baseline to monitor treatment effectiveness over time 1.