HEART-RATE-VARIABILITY IN DEPRESSED-PATIENTS AND DIFFERENTIAL-EFFECTSOF PAROXETINE AND AMITRIPTYLINE ON CARDIOVASCULAR AUTONOMIC FUNCTIONS

Twenty-four unmedicated patients with episodes of major depression (DS M-III-R) and an age- and sex-matched group of 24 normal subjects under went a heart rate analysis. The battery of cardiovascular reflex tests included the coefficient of variation while resting (CVr) and during deep breathing (CVdr), a spectral analysis of heart rate variability, the Valsalva test, and the posture index. The depressed patients showe d no significant abnormities in any of the tests as compared to the he althy subjects. The 24 patients were randomly allocated for treatment with either amitriptyline or paroxetine. During treatment with 20 mg p aroxetine per day, patients showed no changes in cardiovascular autono mic function tests after 14 days. However, treatment with 150 mg amitr iptyline per day decreased all heart rate parameters significantly due to anticholinergic side effects, except heart rate, which increased s ignificantly. As autonomic side effects are a potential hazard of anti depressant therapy, the data suggest that paroxetine is an appropriate antidepressant for cases with pre-existing cardiovascular autonomic n europathy.