Clinical Geriatrics

To the Editor:

I was delighted to see your Psychiatry Rounds article, “Anxiety, Headaches, Insomnia, Restless Legs, and Hypertension: Multiple Disorders or One Problem?”1 I have long recognized a TRIAD: anxiety, restless legs syndrome (RLS), and labile hypertension. As a psychiatrist, I use small doses of clonazepam in these persons to treat three disorders with one drug. I have never before seen “my TRIAD” in print.

I suspect that a deficiency of cytochrome P4501A2, known to be a factor in anxiety, is the cause. Deficient individuals metabolize methylxanthines* at 2 percent of the normal rate. The “caffeine” (methylxanthine) just whirls around and around, causing the following:

1. Increases anxiety (? “biofeedback” from increased heart rate, increased cerebral activity [ie, decreased inhibitory activity])
2. Changes the amount of endogenous vasoconstrictors made in cerebral blood vessels (increasing headache)
3. Increases cerebral excitation (insomnia)
4. Keeps heart rate and blood pressure up (hypertension, tachycardia; methylxanthines directly affect heart rate)
5. Increases RLS if decreased cerebral inhibition?

*caffeine, aminophylline (tea), or theobromine (chocolate)

Sincerely,
Susan D. Delaney, MD, MS
Plano, TX

Reference
1. Lantz MS. Anxiety, headaches, insomnia, restless legs, and hypertension: Multiple disorders or one problem? Clinical Geriatrics 2007;15(4):16-19.

Dr. Lantz responds:

I would like to thank Dr. Delaney for her insightful reply. I have always felt that we miss a large number of food- and drug-induced symptoms, simply by not asking enough about the dietary habits of our patients. I recently saw an 87-year-old woman who told me that chocolate makes her anxious. Whenever she tried chocolate, she became nervous and would spend the next day in bed due to fearfulness. On further questioning, she reported that her mother and grandmother also avoided chocolate for the same reason. This patient also reported being treated with chlorpromazine many years ago for her anxiety and suffering from severe lethargy and sedation. Most phenothiazine antipsychotic agents are metabolized by the cytochrome P4501A2 isozyme.1 This patient may well be among the 2% of individuals who are deficient in this isozyme, as Dr. Delaney describes.

Taking a thorough history, paying attention to what our patients eat and drink, and listening to their complaints with a high index of suspicion can make the difference between an accurate diagnosis or another treatment failure.

Sincerely,
Melinda S. Lantz, MD
Series Editor, AAGP Psychiatry Rounds
Chief of Geriatric Psychiatry
Beth Israel Medical Center
New York, NY

Reference
1. Maletta GJ. Pharmacotherapy in the elderly. In: Agronin ME, Maletta GJ, eds. Principles and Practice of Geriatric Psychiatry. Philadelphia, PA: Lippincott, Williams & Wilkins; 2006:199-220.