title: Does the association between mitral valve prolapse and panic disorder really exist?
abstract: OBJECTIVE
  Although the possible relationship between panic disorder and mitral valve prolapse (MVP) attracted considerable research interest in the 1980s and 1990s, the reported prevalence of MVP in these patients has been inconsistent and widely variable. Clinical and epidemiologic studies have produced controversial data on possible association or definite causal relationship between these 2 entities. The primary objective of the present review was to summarize the current state of knowledge on the association between panic disorder and MVP, including the influence of diagnostic criteria for MVP on the controversial results.
  
  
  METHODS
  We searched MEDLINE, LILACS, and EMBASE databases using the keywords panic and mitral. Inclusion criteria were articles concerning the reciprocal association of MVP and panic disorder, published from the earliest dates available through December 2006.
  
  
  METHODS
  All relevant articles published in English, Spanish, or Portuguese and reporting original data related to the association of MVP and panic disorder were included. Forty articles fulfilling the criteria for inclusion in this review were identified.
  
  
  RESULTS
  Even though the reported prevalence of MVP in panic disorder varied from 0% to 57%, a significant association between the 2 disorders was documented in 17 of the 40 studies. Such inconsistent results were due to sampling biases in case or control groups, widely different diagnostic criteria for MVP, and lack of reliability of MVP diagnosis. None of the reviewed studies used the current state-of-the-art diagnostic criteria for MVP to evaluate the volunteers. Apparently, the more elaborate the study methodology, the lower the chance to observe a significant relationship between these 2 conditions.
  
  
  CONCLUSIONS
  Published results are insufficient to definitely establish or to exclude an association between MVP and panic disorder. If any relationship does actually exist, it could be said to be infrequent and mainly occur in subjects with minor variants of MVP. To clarify this intriguing issue, future studies should mainly focus on the observed methodological biases and particularly should use the current criteria for MVP as the standard for evaluation.
authors.affiliation: Department of Neuropsychiatry and Medical Psychology, School of Medicine of Ribeirão Preto, São Paulo University, Brazil.
authors.forename: Alaor Santos
authors.initials: AS
authors.lastname: Filho
authors.forename: Benedito C
authors.initials: BC
authors.lastname: Maciel
authors.forename: Rocío
authors.initials: R
authors.lastname: Martín-Santos
authors.forename: Minna M D
authors.initials: MM
authors.lastname: Romano
authors.forename: José Alexandre
authors.initials: JA
authors.lastname: Crippa