title: Quality of management of oral anticoagulation as assessed by time in therapeutic INR range in elderly and younger patients with low mean years of formal education: a prospective cohort study.
abstract: BACKGROUND
  despite the overwhelming evidence of its effectiveness, oral anticoagulation continues to be underused in the elderly, presumably due to physicians' misconceptions when estimating bleeding risk and ability to comply with treatment.
  
  
  OBJECTIVE
  to investigate the quality of anticoagulation control among deprived elderly and younger patients.
  
  
  METHODS
  prospective observational study.
  
  
  METHODS
  a public anticoagulation clinic in a developing country.
  
  
  METHODS
  all adult patients on intended long-term (>90 days) oral anticoagulation. We studied 171 patients (79 elderly and 92 non-elderly) with a mean follow-up of 273 ± 84.9 days.
  
  
  METHODS
  the main outcome measure was the quality of anticoagulation management as measured by the time in therapeutic (TTR) international normalised ratio (INR) range. Elderly patients (≥60 years) were compared with younger patients with respect to the educational level and co-morbidities.
  
  
  RESULTS
  the mean number of years of formal education was 4.37 ± 3.2 years. The mean TTR was 62.50 ± 17.9% in non-elderly and 62.10 ± 16.6% in elderly (P = 0.862) subjects, despite the higher prevalence of co-morbidities in the latter group: heart failure (46.3 versus 28.6%, P = 0.042), diabetes mellitus (22.8 versus 8.7%, P = 0.011), renal failure (estimated glomerular filtration rate <50 ml/min: 38.0 versus 7.1%, P < 0.001) and polypharmacy (84.8 versus 58.7%, P < 0.001). Fifty elderly and 84 non-elderly subjects require little or no assistance in taking medications. Among them, the elderly had lower educational levels (3.42 ± 2.5 versus 5.55 ± 3.4 years of formal education, P < 0.001) and higher rates of cognitive impairment (34.0 versus 13.1%, P = 0.004), but a similar mean TTR (62.46 ± 16.1 versus 63.02 ± 17.8%, P = 0.856). The oldest (≥75 years) patients did as well as those aged ≤50 years (mean TTR: 62.54 ± 16.0 versus 62.23 ± 16.4%, respectively, P = 0.98).
  
  
  CONCLUSIONS
  good-quality management of oral anticoagulation is achievable in deprived populations attending an anticoagulation clinic. Elderly patients may experience similar quality of anticoagulation despite having higher levels of co-morbidities and polypharmacy. These results add evidence to the safety of such therapeutic interventions in the elderly.
authors.affiliation: Department of Internal Medicine, Hospital Municipal Odilon Behrens, Rua Formiga, 50, Belo Horizonte, MG 31.110-430, Brazil. gustavolamego@ig.com.br
authors.forename: Gustavo Lamego de Barros
authors.initials: GL
authors.lastname: Costa
authors.forename: Diana Carvalho
authors.initials: DC
authors.lastname: Ferreira
authors.forename: Reginaldo Aparecido
authors.initials: RA
authors.lastname: Valacio
authors.forename: Maria da Consolação
authors.initials: Mda C
authors.lastname: Vieira Moreira
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000627:therapeutic use*; D001938:Brazil; D002318:Cardiovascular Diseases / Q000188:drug therapy*; D004522:Educational Status; D005260:Female; D005500:Follow-Up Studies; D006779:Hospitals, Public; D006801:Humans; D019934:International Normalized Ratio; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D011446:Prospective Studies; D011787:Quality of Health Care; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000925:Anticoagulants