Chapter 20-15: Morning Headaches as Symptoms of Other Diseases

TEXTBOOK PRESENTATION

Various diseases can cause headaches that occur predominantly in the morning. The headaches are generally worst upon awakening and then improve as the day progresses. Classically, the more common symptoms of the underlying disease (daytime hypoglycemia with overly controlled diabetes mellitus or daytime somnolence with OSA) are present.

DISEASE HIGHLIGHTS

1. The most rigorously defined morning headaches are those caused by disturbed sleep. The sleep disturbance can be of almost any etiology.

   1. Primary sleep disturbance

      1. OSA

      2. Periodic leg movement of sleep (PLMS)

   2. Abnormal sleep duration

      1. Excessive sleep

      2. Interrupted sleep

      3. Sleep deprivation

   3. Secondary to another disease

      1. Chronic pain

      2. Depression

2. Hypoglycemia that occurs while asleep or awake can cause headaches.

EVIDENCE-BASED DIAGNOSIS

1. The attribution of morning headaches to another disease depends on the recognition of the underlying disease, its treatment, and the response of the presenting headache.

2. Recognition of the OSA and nighttime hypoglycemia can be difficult since clinical clues are nonspecific.

   1. Clinical predictors of OSA are poor (See Evidence Based Diagnosis). Polysomnography is diagnostic and will also provide information about PLMS and, sometimes, insomnia related to chronic pain.

      A sleep study is a reasonable diagnostic test in a patient with morning headaches and no readily apparent cause.

   2. Nighttime hypoglycemia should be considered in any patient with morning headaches who is treated for diabetes. Abnormal nocturnal glucose readings and resolution of headaches with achievement of euglycemia are diagnostic.

TREATMENT

The treatment of morning headaches depends on the cause.

1. Nighttime hypoglycemia: improve management of diabetes mellitus

2. OSA: Continuous positive airway pressure

3. PLMS: Carbidopa and levodopa

4. Pain syndromes: Improve pain control