title: Predictors and prognosis of paroxysmal atrial fibrillation in general practice in the UK.
abstract: BACKGROUND
  Natural history of paroxysmal atrial fibrillation (AF) is not very well documented. Clinical experience suggests that paroxysmal AF could progress to chronic AF with estimates ranging between 15 and 30% over a period of 1-3 years. We performed an epidemiologic study to elucidate the natural history of paroxysmal AF, this study estimated its incidence in a general practice setting, identified associated factors and analyzed the progression into chronic AF as well as the mortality rate.
  
  
  METHODS
  Using the UK General Practice Research Database (GPRD), we identified patients aged 40-89 years with a first-recorded episode of paroxysmal AF during 1996. Risk factors were assessed using 525 incident paroxysmal AF cases confirmed by the general practitioner (GP) and a random sample of controls. We follow-up paroxysmal AF patients and estimated their mortality rate and progression to chronic AF.
  
  
  RESULTS
  The incidence of paroxysmal AF was 1.0 per 1,000 person-years. Major risk factors for paroxysmal AF were age and prior valvular heart disease, ischaemic heart disease, heart failure and hyperthyroidism. During a mean follow-up of 2.7 years, 70 of 418 paroxysmal AF patients with complete information progressed to chronic AF. Risk factors associated with progression were valvular heart disease (OR 2.7, 95% CI 1.2-6.0) and moderate to high alcohol consumption (OR 3.0, 95% CI 1.1-8.0). Paroxysmal AF patients did not carry an increased risk of mortality, compared to an age and sex matched sample of the general population. There was a suggestion of a small increased risk among patients progressing to chronic AF (RR 1.5, 96% CI 0.8-2.9).
  
  
  CONCLUSIONS
  Paroxysmal AF is a common arrhythmia in the general practice setting, increasing with age and commonly associated with other heart diseases. It sometimes is the initial presentation and then progress to chronic AF. A history of valvular heart disease and alcohol consumption are associated with this progression.
authors: Centro Español de Investigación Farmacoepidemiológica (CEIFE), Madrid, Spain. aruigomez@ceife.es
authors: Ana
authors: A
authors: Ruigómez
authors: Saga
authors: S
authors: Johansson
authors: Mari-Ann
authors: MA
authors: Wallander
authors: Luis Alberto
authors: LA
authors: García Rodríguez
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000428:Alcohol Drinking / Q000453:epidemiology; D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality; D002318:Cardiovascular Diseases / Q000150:complications; D002908:Chronic Disease; D005194:Family Practice; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000150:complications; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012307:Risk Factors; D006113:United Kingdom / Q000453:epidemiology