Night-Shift Bus Driver with Sleepiness
A 52-year-old city bus driver works rotating 12-hour shifts, including frequent night shifts, and has done so for 8 years. Over the past 3 months he has had increasing daytime sleepiness, and last week he nodded off at a red light for a few seconds. He is obese (BMI 34), reports loud snoring and witnessed apneas, and has hypertension. He has no prior motor vehicle crashes. He is on no sedating medications and does not drink alcohol. His employer's medical review officer asks you to determine fitness for duty. He is eager to keep driving because he is the family's sole earner.
1. What is the most likely diagnosis, and how should you frame the fitness-for-duty decision right now?
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Most likely diagnosis: obstructive sleep apnea (OSA), likely moderate-to-severe, given obesity, loud snoring, witnessed apneas, hypertension, and daytime sleepiness with a near-miss event. The rotating 12-hour schedule with night shifts compounds his sleep debt and circadian disruption.
Fitness decision now: He is not fit for unrestricted commercial driving pending evaluation. The near-miss (nodding off at a red light) is a red flag for crash risk. The appropriate action is:
- Temporary restriction from driving until OSA is evaluated and treated, or at minimum until a sleep specialist assessment and a documented treatment plan are in place.
- Refer urgently for a sleep study (polysomnography or home sleep apnea test) and to a sleep specialist.
- Do not simply clear him because he has no crash history - the near-miss is the warning sign.
- Coordinate with the employer's MRO and the driver's union/HR on light duty or leave options so he is not forced to choose between driving and income.
2. Assuming OSA is confirmed and he is started on CPAP, what conditions would you set for returning him to driving, and what schedule changes do you recommend?
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Return-to-driving conditions (documented, objective):
- Adherence to CPAP - objective compliance data (e.g., ≥4 hours/night on ≥70% of nights) demonstrated over a defined period (commonly 4–8 weeks) before unrestricted duty.
- Symptom resolution - no daytime sleepiness, no near-misses, and a normal Epworth Sleepiness Scale score.
- Specialist sign-off - sleep specialist confirms effective treatment.
- Ongoing monitoring - periodic review of compliance and symptoms; a written agreement that he will report recurrence of sleepiness.
Schedule recommendations:
- Reduce reliance on rotating 12-hour shifts; forward-rotating schedules are better tolerated than backward-rotating ones.
- Ensure adequate rest between shifts (minimum 8–10 hours off).
- Limit consecutive night shifts and provide scheduled rest breaks.
- Address hypertension and weight as part of the overall fitness plan.
Document all conditions in the fitness-for-duty report and share only the functional restrictions with the employer, keeping clinical details confidential.