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Power spectral analysis of the heart rate was compared with standard tests of autonomic function performed on 15 insulin-dependent diabetic patients with symptoms of autonomic dysfunction. The high-frequency power, low-frequency power, and total power of the heart rate power spectrum measured in the supine position--possible measures of parasympathetic nervous system function--were significant predictors of the expiratory-inspiratory ratio, the beat-to-beat heart rate difference on deep respiration, the standard deviation of the resting heart rate, the 30:15 ratio, and the Valsalva ratio. The change in low-frequency power on moving from the supine to upright position, a possible measure of sympathetic nervous system function, was a modest predictor of the systolic and diastolic blood pressure fall in response to postural change, but a poor predictor of the blood pressure response to isometric exercise and a cold stimulus. This study supports the role of heart rate power spectral analysis as a clinical test of autonomic function in patients with known or suspected autonomic failure.

The etiology of autonomic neuropathy in insulin-dependent diabetes mellitus (IDDM) is unknown. Previous studies have noted the presence of anti-adrenal medullary antibodies in IDDM. Recently, we have also demonstrated the presence of anti-sympathetic ganglia antibodies in IDDM. We initiated a study to evaluate whether subjects with complement-fixing anti-adrenal medullary (CF-ADM) and anti-sympathetic ganglia (CF-SG) antibodies have a decreased catecholamine response to change in posture. Seven IDDM subjects aged 19–41 yr with duration of disease 5–21 yr at the time of the posture study were evaluated. Serums collected longitudinally were evaluated for the presence of CF-ADM and CF-SG antibodies. Three IDDM subjects were CF-ADM− and CF-SG− at all testing intervals (Ab− group). Four IDDM subjects were CF-ADM+ and/or CF-SG+ on at least one testing date (Ab+ group). Baseline mean norepinephrine and epinephrine levels were not significantly different in Ab+ and Ab− subjects. Norepinephrine levels 5 min after standing were mean ± SD 227 ±16 and 419 ± 48 pg/ml for Ab+ and Ab− subjects, respectively (P < .03). The means of the 5-min minus basal norepinephrine levels were 88 ± 42 (Ab+) and 207 ± 26 (Ab−) pg/ml (P < .03). Mean epinephrine levels after 5 min of standing were 35 ±16 (Ab+) and 101 ± 44 (Ab−) pg/ml (P < .03). The means of the 5-min minus basal epinephrine levels were 1 ± 5 (Ab+) and 43 ± 38 (Ab) pg/ml (P < .03). Mean change in systolic blood pressure on standing was not different in the two groups. This suggests that CF-ADM and CF-SG are associated with a decreased catecholamine response to change in posture.

A 58-year-old woman developed acute, transient expressive aphasia and right arm weakness. Evaluation revealed subclinical cardiomyopathy and a ventricular mural thrombus that were attributed to adriamycin therapy. Adriamycin cardiomyopathy predisposed the patient to ventricular thrombus formation and subsequent arterial embolization.

• To investigate the biological and functional significance of cerebral asymmetries, we measured lateral differences of the frontal and occipital poles on computed tomographic scans of 66 adult outpatients with no diagnosed abnormalities. In addition to confirming the greater average sizes of the right frontal and left occipital poles, we found a significant linear correlation relating anterior and posterior difference measures. Men showed greater degrees of frontal and occipital asymmetries than women; reversals of the typical asymmetries were more common among women. Reduction or reversal of the usual left occipital predominance in the presence of typical right frontal predominance was associated with non-right-handedness. These findings clarify and extend prior qualitative observations and relate to the possible role of testosterone in modulation of cortical asymmetries. Reduced structural asymmetries among women and nonright-handers may provide an anatomical basis for clinical and laboratory findings of lessened functional lateralization in these groups.

• Deficits in cognition and behavior have frequently been described in severely depressed patients. Recent reports have drawn attention to focal left-sided neurologic findings occurring in depression. We describe a depressed patient with marked cognitive and behavioral impairment and focal left-sided signs. The depression, mental status deficits, and physical findings all resolved after electroconvulsive therapy.