Age as a determinant of adverse events in medically treated cryptogenic stroke patients with patent foramen ovale.

BACKGROUND AND PURPOSE Patent foramen ovale (PFO) is associated with cryptogenic stroke. There is no study that assessed the effect of age on adverse event rates in cryptogenic stroke patients with PFO. The purpose of this retrospective analysis from PFO in Cryptogenic Stroke Study (PICSS) database was to assess the effect of age on the risk of adverse events in medically treated cryptogenic stroke patients with PFO. METHODS 250 cryptogenic stroke patients from PICSS were followed-up for 24 months, with death and recurrent ischemic stroke as primary endpoints. Hazard ratios were calculated for determination of relative risk in cryptogenic stroke patients with and without PFO in 3 age groups (younger than 55, 55 to 64, and 65 years or older). RESULTS Among the 2 younger age groups, the presence of PFO did not significantly affect the risk of adverse events (P=0.15; hazard ratio=0.21; 95% CI, 0.02 to 1.78; 2-year event rates, 2.0% versus 9.3%; and P=0.70; hazard ratio=0.72; 95% CI, 0.14 to 3.73; 2-year event rates, 10.0% versus 13.9%). However, in those aged 65 years or older, the risk of adverse events was significantly higher in the patients with PFO (P=0.01; hazard ratio=3.21; 95% CI, 1.33 to 7.75; 2-year event rates 37.9% versus 14.5%). CONCLUSIONS In this exploratory analysis, the presence of PFO in the younger cryptogenic stroke patients did not increase the risk of adverse events. However, in the older patients, PFO significantly increased the risk of adverse events.