Table 2.

Univariate and multivariate regression analyses to detect independent patient and treatment characteristics to predict initial seizure threshold (IST), and mixed analyses to detect independent predictors of the variation in seizure threshold (ST) during the course of electroconvulsive therapy (ECT)

	Univariate correlates of IST at baseline		Multivariate correlates of ISTa at baseline		Multivariate correlates of STa during follow-up
	β-coefficient	P value	β-coefficient	P value	β-coefficient	P value
Patient characteristics
Male gender	−0.043	0.682
Age, in years	0.466	<0.001	0.238	0.033	0.279	0.009
Body mass index, in kg/m2	−0.156	0.143
CIRS scored	0.385	<0.001	0.154	0.131	0.127	0.227
Diagnostic category, according to axis 1 of DSM-IV-Rf
Depressive disorder without psychotic features	−0.064	0.544
Depressive disorder with psychotic features	0.030	0.781
Bipolar disorder, depressive episode	0.076	0.476
Other disorderse	−0.046	0.664
Documented or clinically suspected personality disorder present, according to axis 2 of DSM-IV-R	−0.134	0.207
MADRSb score at baseline	0.082	0.450
MMSEc score at baseline	−0.331	0.002	−0.045	0.641	0.058	0.549
Treatment characteristics
Had previous course(s) of ECT	0.346	0.001	0.059	0.579	−0.052	0.564
Days between last ECT and index ECT	−0.064	0.746
Use of seizure threshold influencing concomitant pharmacotherapy
Benzodiazepines	0.033	0.758
Antiepileptics	0.027	0.803
Antidepressants	0.084	0.431
Antipsychotics	−0.112	0.289
Electrode placement is bifrontotemporal	0.546	<0.001	0.424	<0.001	0.348	<0.001
Dynamic impedance	−0.248	0.018	−0.082	0.344	−0.107	0.062
Etomidate dose	−0.084	0.427
Succinylcholine dose	−0.295	0.005	−0.071	0.452	−0.056	0.376

^aMultivariate regression analysis and mixed analysis only for variables showing P < 0.10 at univariate analysis

^bMontgomery–Åsberg Depression Rating Scale

^cMini-Mental State Examination

^dCumulative Illness Rating Scale

^eSchizophrenia (n = 2) and malignant neuroleptic syndrome (n = 1)

^fDiagnostic and Statistical Manual of Mental Disorders