Risk Factors for Complications of Drug-Induced Seizures

The purpose of this study is to determine clinical factors associated with complications of drug-induced seizures. This prospective observational study was conducted at an American Association of Poison Control Centers-certified regional poison control center (PCC) over a 1-year period. All consecutive cases reported to a PCC involving seizures were forwarded to investigators, who obtained standardized information including the specific drug or medication exposure, dose, reason for exposure, vital signs, laboratory data, treatment, and outcome. Patients were monitored by daily telephone follow-up until death or discharge. Subjects were excluded if the seizure was deemed to be unrelated to exposure. Odds ratios were used to analyze variables for associations with admission to the hospital for >72 h, endotracheal intubation, status epilepticus, anoxic brain injury, or death. One hundred twenty-one cases met inclusion criteria. Sixty-three (52%) were male, and the mean age was 30 (SD14) years. Common exposures included: antidepressants (33%), stimulants (15%), and anticholinergics (10%). One hundred and three (85%) of the exposures were intentional, of which 74 were suicide attempts and 16 were drug abuse or misuse. Forty-nine (40%) patients required endotracheal intubation, 12(10%) had status epilepticus, 50(41%) were hospitalized for more than 72 h, and one patient died. Median hospital stay was 3 days. Variables significantly associated with complications included stimulant exposure (odds ratios, OR = 11 [95% confidence intervals (CI) 1.9–52]), suicide attempt (OR = 2.2 [95% CI 1.02–4.7]), initial hypotension (OR = 11.2 [95% CI 1.4–89.3]), admission glucose >130 mg/dL (OR = 5.4 [95% CI 1.6–18.1]), and admission HCO(3) < 20 mEq/L (OR = 4.0 [95% CI 1.4–11.3]). Significant clinical factors associated with complications of drug-related seizures include stimulant exposure, suicide attempt, initial hypotension, and admission acidosis or hyperglycemia.