DALLAS — A quick, six-question survey can diagnose anxiety in patients who've had a myocardial infarction and identify those who need treatment with an anxiolytic.
“The Brief Symptom Inventory [BSI] is performed similarly to the State Anxiety Instrument [SAI]. The brief symptom inventory is a valid instrument for quickly diagnosing anxiety and identifying patients who need anxiolytic therapy,” Mohannad Abu Ruz said at the annual scientific sessions of the American Heart Association.
“It's important to treat anxiety during the first 72 hours following a myocardial infarction, but few patients get their anxiety level measured following an infarction,” said Mr. Abu Ruz, a nursing-PhD candidate at the University of Kentucky in Lexington. “There is a belief that the diagnostic instruments are time consuming and burdensome to patients, and many physicians rely on physiologic indicators of anxiety such as blood pressure and heart rate.”
The study involved 536 patients admitted for an acute MI at any of five participating hospitals in the United States and Australia. MIs were confirmed by ECG and cardiac enzymes.
Within 72 hours of admission, all patients were assessed for their anxiety level using the SAI, the standard diagnostic tool for anxiety, and by the BSI, which can be administered in 2–5 minutes.
Questions on the BSI all use simple language and are structured to ask about the patient's mental state at the time of the interview—for example, “Are you nervous at this time?”
Answers are measured on a 0–4 scale, with 0 meaning no anxiety and 4 meaning a high level of anxiety. The ideal is an answer of 0 for all six questions.
For this study, an MI patient who scored 2 or more points on the BSI was considered anxious enough to need treatment.
A total of 261 were diagnosed as anxious using the SAI, and 262 were diagnosed as anxious by the BSI, producing a correlation coefficient of 0.7—a good level of correlation between the two measures, Mr. Aub Ruz said.
Further confirmation of the validity of BSI was based on the mean number of in-hospital complications experienced by the patients diagnosed as anxious or not anxious.
With diagnoses based on the SAI, patients who were anxious had an average of 1.3 complications during hospitalization, compared with 0.8 complications per patient among those who were not anxious.
Identical complication rates were seen when patients were categorized by the BSI, Mr. Abu Ruz reported.
In a logistic regression analysis, a diagnosis of anxiety using the BSI was a predictor of subsequent complications independent of other clinical and demographic factors including age, gender, smoking history, comorbidities, left ventricular ejection fraction, and Killip classification.
Patients diagnosed with anxiety immediately after a myocardial infarction should be treated with an anxiolytic drug for the next 3 days, or until they are discharged from the ICU or coronary care unit, Mr. Abu Ruz said. A typical regimen at his institution is 2.5–5 mg of diazepam q.i.d.