title: Annual rates of admission and seasonal variations in hospitalizations for heart failure.
abstract: OBJECTIVE
  To investigate the annual hospitalization rate and seasonal variation in confirmed heart failure (HF) admissions.
  
  
  RESULTS
  Records from all admissions to one hospital during 1 year with a HF diagnostic code were reviewed. From 1953 admissions, 595 were excluded because they did not fulfill the diagnostic criteria. A total of 1069 patients had 1358 admissions with confirmed HF. Mean age was 74.8 +/- 11.5 years, 42% were males. The admission data were matched with data from the municipal census with 537,666 people aged > or = 15 years. There were 2.5 admissions per 1000 for the adult population and 26.5/1000 in those aged > or = 80 years. There were 444 males and 625 females, giving a higher rate of admission for female patients 2.2/1000 vs. 1.7/1000 (P < 0.0001), although age adjusted rates in females were higher only for > or = 80 years. Echocardiogram was performed in 706 patients (66%), 325 (46%) had a normal ejection fraction. This proportion increased in females--64% vs. 29% males--and in older patients--55% in > or = 75 vs. 39% in < 75 years. Mortality during the first admission of 1996 was 8.3%. There was a seasonal variation in HF hospitalizations (P < 0.0001) peaking at 25% above average in January and dipping to 33% below average in August.
  
  
  CONCLUSIONS
  The rate of HF admissions was 2.5/1000 with an elderly preponderance and a higher rate of admission in males < 80 years and in females > or = 80 years. A seasonal variation ranging from 25% above average in January to 33% below average in August was observed.
authors.affiliation: Cardiology Department, Hospital Universitario Gregorio Marañón, Dr Esquerdo, 46, 28007-Madrid, Spain. mmselles@navegalia.com
authors.forename: Manuel
authors.initials: M
authors.lastname: Martínez-Sellés
authors.forename: José A
authors.initials: JA
authors.lastname: García Robles
authors.forename: Luis
authors.initials: L
authors.lastname: Prieto
authors.forename: José A
authors.initials: JA
authors.lastname: Serrano
authors.forename: Roberto
authors.initials: R
authors.lastname: Muñoz
authors.forename: Elisa
authors.initials: E
authors.lastname: Frades
authors.forename: Jesús
authors.initials: J
authors.lastname: Almendral
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D005260:Female; D005500:Follow-Up Studies; D019538:Health Care Surveys; D006333:Heart Failure / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D010507:Periodicity; D016012:Poisson Distribution; D011336:Probability; D012042:Registries; D012307:Risk Factors; D012621:Seasons; D012720:Severity of Illness Index; D017678:Sex Distribution; D013030:Spain / Q000453:epidemiology