title: Particulate air pollution and hospital admissions for cardiac diseases in potentially sensitive subgroups.
abstract: BACKGROUND
  Although numerous studies have provided evidence of an association between ambient air pollution and acute cardiac morbidity, little is known regarding susceptibility factors.
  
  
  METHODS
  We conducted a time-stratified case-crossover study in 9 Italian cities between 2001 and 2005 to estimate the short-term association between airborne particles with aerodynamic diameter <10 μm (PM10) and cardiac hospital admissions, and to identify susceptible groups. We estimated associations between daily PM10 and all cardiac diseases, acute coronary syndrome, arrhythmias and conduction disorders, and heart failure for 167,895 hospitalized subjects ≥ 65 years of age. Effect modification was assessed for age, sex, and a priori-defined hospital diagnoses (mainly cardiovascular and respiratory conditions) from the previous 2 years as susceptibility factors.
  
  
  RESULTS
  The increased risk of cardiac admissions was 1.0% (95% confidence interval [CI] = 0.7% to 1.4%) per 10 μg/m PM10 at lag 0. The effect was slightly higher for heart failure (lag 0, 1.4% [0.7% to 2.0%]) and acute coronary syndrome (lag 0-1, 1.1% [0.4% to 1.9%]) than for arrhythmias (lag 0, 1.0% [0.2% to 1.8%]). Women were at higher risk of heart failure (2.0% [1.2% to 2.8%]; test for interaction, P = 0.022), whereas men were at higher risk of arrhythmias (1.9% [0.8% to 3.0%]; test for interaction, P = 0.020). Subjects aged 75-84 years were at higher risk of admissions for coronary events (2.6% [1.5% to 3.8%]; test for interaction, P = 0.001). None of the identified chronic conditions was a clear marker of susceptibility.
  
  
  CONCLUSIONS
  An important effect of PM10 on hospitalizations for cardiac diseases was found in Italian cities. Sex and older age were susceptibility factors.
authors.affiliation: Department of Epidemiology, Regional Health Service, Lazio Region, via S. Costanza 53, Rome, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Colais
authors.forename: Annunziata
authors.initials: A
authors.lastname: Faustini
authors.forename: Massimo
authors.initials: M
authors.lastname: Stafoggia
authors.forename: Giovanna
authors.initials: G
authors.lastname: Berti
authors.forename: Luigi
authors.initials: L
authors.lastname: Bisanti
authors.forename: Ennio
authors.initials: E
authors.lastname: Cadum
authors.forename: Achille
authors.initials: A
authors.lastname: Cernigliaro
authors.forename: Sandra
authors.initials: S
authors.lastname: Mallone
authors.forename: Barbara
authors.initials: B
authors.lastname: Pacelli
authors.forename: Maria
authors.initials: M
authors.lastname: Serinelli
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Simonato
authors.forename: Maria Angela
authors.initials: MA
authors.lastname: Vigotti
authors.forename: Francesco
authors.initials: F
authors.lastname: Forastiere
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000032:analysis / Q000633:toxicity*; D000397:Air Pollution / Q000009:adverse effects* / Q000032:analysis; D018592:Cross-Over Studies; D015987:Effect Modifier, Epidemiologic; D005260:Female; D006331:Heart Diseases / Q000139:chemically induced* / Q000453:epidemiology; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects* / Q000032:analysis; D007558:Italy / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D052638:Particulate Matter / Q000032:analysis / Q000633:toxicity*; D010343:Patient Admission / Q000706:statistics & numerical data*; D012307:Risk Factors; D012737:Sex Factors
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter