title: Interaction between proatherosclerotic factors and right-to-left shunt on the risk of cryptogenic stroke: the Italian Project on Stroke in Young Adults.
abstract: OBJECTIVE
  To explore the interaction effects between cardiac interatrial right-to-left shunt (RLS) and proatherosclerotic factors on the risk of brain ischaemia.
  
  
  METHODS
  Multicentre Italian case-control study.
  
  
  METHODS
  University hospitals.
  
  
  METHODS
  588 patients with cryptogenic stroke (CS) aged ≤45 years and 585 control subjects consecutively enrolled as part of the Italian Project on Stroke in Young Adults.
  
  
  METHODS
  Interaction effects between RLS and an individual proatherosclerotic score computed from the number of conventional vascular risk factors for the risk of CS were investigated. Data were examined by logistic regression models and expressed as interaction OR or interaction risk difference (RD).
  
  
  RESULTS
  CS risk increased with increasing number of proatherosclerotic factors in subjects without RLS (OR 2.73; 95% CI 1.98 to 3.76; RD +0.246; 95% CI +0.17 to +0.32; for subjects with one or more factors), but was higher in subjects with RLS and no additional proatherosclerotic factors (OR 5.14; 95% CI 3.49 to 7.58; RD +0.388; 95% CI +0.31 to +0.47) compared with subjects without RLS and no risk factors. Negative interaction and antagonistic effects between RLS and proatherosclerotic factors were observed (interaction OR 0.52; 95% CI 0.31 to 0.91; interaction RD -0.17; 95% CI -0.29 to -0.05).
  
  
  CONCLUSIONS
  The influence of RLS on the risk of CS decreases with increasing number of atherosclerotic factors, and is highest when such factors are absent. Individual proatherosclerotic profiles may help to identify patients with CS whose patent foramen ovale is probably pathogenic.
authors.affiliation: Dipartimento di Scienze Mediche e Chirurgiche, Clinica Neurologica, Università degli Studi di Brescia, P.le Spedali Civili, 1, 25100 Brescia, Italia. ale_pezzini@hotmail.com
authors.forename: Alessandro
authors.initials: A
authors.lastname: Pezzini
authors.forename: Mario
authors.initials: M
authors.lastname: Grassi
authors.forename: Corrado
authors.initials: C
authors.lastname: Lodigiani
authors.forename: Rosalba
authors.initials: R
authors.lastname: Patella
authors.forename: Carlo
authors.initials: C
authors.lastname: Gandolfo
authors.forename: Andrea
authors.initials: A
authors.lastname: Zini
authors.forename: Rossella
authors.initials: R
authors.lastname: Musolino
authors.forename: Rocco Salvatore
authors.initials: RS
authors.lastname: Calabrò
authors.forename: Paolo
authors.initials: P
authors.lastname: Bovi
authors.forename: Alessandro
authors.initials: A
authors.lastname: Adami
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: DeLodovici
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Del Zotto
authors.forename: Lidia Luciana
authors.initials: LL
authors.lastname: Rota
authors.forename: Maurizia
authors.initials: M
authors.lastname: Rasura
authors.forename: Massimo
authors.initials: M
authors.lastname: Del Sette
authors.forename: Alessandra
authors.initials: A
authors.lastname: Spalloni
authors.forename: Alessia
authors.initials: A
authors.lastname: Giossi
authors.forename: Irene
authors.initials: I
authors.lastname: Volonghi
authors.forename: Federica
authors.initials: F
authors.lastname: Casoni
authors.forename: Paolo
authors.initials: P
authors.lastname: Cerrato
authors.forename: Paolo
authors.initials: P
authors.lastname: Costa
authors.forename: Mauro
authors.initials: M
authors.lastname: Magoni
authors.forename: Antonella
authors.initials: A
authors.lastname: Toriello
authors.forename: Maurizio
authors.initials: M
authors.lastname: Paciaroni
authors.forename: Giorgio
authors.initials: G
authors.lastname: Dalla Volta
authors.forename: Licia
authors.initials: L
authors.lastname: Iacoviello
authors.forename: Alessandro
authors.initials: A
authors.lastname: Padovani
mesh_terms: D000328:Adult; D050197:Atherosclerosis / Q000150:complications* / Q000209:etiology; D016022:Case-Control Studies; D005260:Female; D054092:Foramen Ovale, Patent / Q000150:complications*; D006801:Humans; D007558:Italy; D008297:Male; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology / Q000209:etiology*