Sudden death due to pulmonary embolism in young adults in Spain. Retrospective multicenter study of 128 forensic autopsy cases.

Introduction and objectives: Pulmonary embolism (PE) may debut as sudden death (SD) in young and middle-aged adults. This study aims to determine the epidemiological and clinicopathological characteristics involved in SD due to PE in this age group and the underlying risk factors.

Methods: Multicenter retrospective noncontrolled study based on forensic autopsies performed in individuals aged 12 to 49 years at 3 forensic pathology services in Spain (Valencia, Biscay, and Seville) over an 8-year period (2010-2017).

Results: A total of 1344 cardiac SD cases were recorded, of which 128 (9.5%) were due to PE (57% male, median age 42 years). The annual incidence was 0.56/100 000 inhabitants/y. The main risk factor was obesity (62%; 18.5% morbid obesity). The mean body mass index was 34.9±13.1. Psychiatric disorders were highly prevalent (44%). Immobilization (26%) and prior trauma (11%) were other relevant antecedents. Among women, 22% were receiving oral contraceptive therapy. Premortem symptoms were reported in 52% of cases, mainly dyspnea (56%). Although 22 individuals sought medical attention, only one was correctly diagnosed. Toxicological analysis was performed in 67% of cases, with positive results for psychotropic drugs (20%) and substances of abuse/alcohol (9%).

Conclusions: PE is a common cause of SD in individuals younger than 50 years and is frequently clinically underdiagnosed. This study provides evidence supporting a strong association with obesity and psychiatric disorders, which facilitate immobilization, venous stasis, and a prothrombotic state. Forensic studies of sudden death due to PE offer complementary data to clinical research, revealing risk factors that are underrepresented in clinical cohorts. .