Age Effect on Electroconvulsive Therapy Seizure Resistance.
To specifically examine the expectation that seizure induction is more difficult in older patients, we studied a consecutive series of 21 men receiving a course of brief-pulse, square-wave, bilateral electroconvulsive therapy (ECT). Each subject received a 144-mC stimulus over 1 s (800-mA, 1.5-ms pulses at 60 Hz) at the second, third, or fourth ECT session, randomly selected. Nine subjects showed no convulsion. Subjects who showed seizure (age 37.7 +/- 13.2 years) were younger (t = 4.178, df = 19, p = 0.00025, one-tailed) than those who did not (age 57.6 +/- 6.1 years). These observations indicate that seizure resistance to bilateral brief-pulse ECT increases strongly with age in men.