Comparison of Specific Fainting Characteristics Between Youth With Tilt-Induced Psychogenic Nonsyncopal Collapse Versus Reflex Syncope

Little is known about the predictive features of psychogenic nonsyncopal collapse (PNSC). The aim of the present study was to compare the self-reported fainting characteristics between young patients who were ultimately diagnosed with PNSC with those ultimately diagnosed with neurally mediated syncope and to determine which features were predictive of either diagnosis. A prospective study was conducted of sequential patients referred for fainting. All study data were obtained before testing or diagnosis. Several fainting characteristics were compared between cohorts including numbers of lifetime fainting episodes, fainting frequency the week before evaluation, fainting duration, numbers of fainting spells in a single day, presence of presyncope, types of prodromal symptoms, tearfulness with fainting, and the numbers of emergency department visits and hospital admission for fainting. During the study period, 52 patients were diagnosed with PNSC, producing a diagnostic rate of 18.9%. In univariate analyses, multiple features differed between patients with PNSC and those with syncope. After controlling for age and gender in a multivariate analysis, each of the following predicted PNSC: ≥20 lifetime fainting spells (p = 0.005), ≥2 fainting spells in a single day (p = 0.03), self-reported loss of consciousness ≥2 minutes (p = 0.01), and tearfulness associated with fainting (p = 0.022). Two or more typical prodromal symptoms (p = 0.004) predicted syncope. In conclusion, several characteristics related to fainting have predictive value in distinguishing PNSC from syncope, particularly among youth. Assessing these clinical features can help to inform appropriate testing and accurate diagnosis among patients who faint.