Sunday, November 27, 2011

Aspirin for primary prevention of vascular events in women: individualized prediction of treatment effects European Heart Journal, 11/17/2011 Clinical Article

Dorresteijn JAN et al. – Aspirin was ineffective or even harmful in the majority of patients. Age was positively related to treatment effect, whereas current smoking and baseline risk for cardiovascular events were not. When the NWT is 50 or lower, the aspirin treatment strategy that is associated with optimal net benefit in primary prevention of vascular events in women is to treat none.
Methods
  • Randomized controlled trial data from the Women's Health Study were used to predict treatment effects for individual women in terms of absolute risk reduction for major cardiovascular events (i.e. myocardial infarction, stroke, or cardiovascular death).
  • Predictions were based on existing risk scores, i.e. Framingham (FRS), and Reynolds (RRS), and on a newly developed prediction model.
  • The net benefit of different aspirin treatment–strategies was compared:
    • Treat no one,
    • Treat everyone,
    • Treatment according to the current guidelines (i.e. selective treatment of women >65 years of age or having >10% FRS),
    • And prediction–based treatment (i.e. selective treatment of patients whose predicted treatment effect exceeds a given decision threshold).
Results
  • The predicted reduction in 10–year absolute risk for major cardiovascular events was <1% in 97.8% of 27 939 study subjects when based on the refitted FRS, in 97.0% when based on the refitted RRS, and in 90.0% when based on the newly developed model.
  • Of the treatment strategies considered, only prediction–based treatment using the newly developed model and selective treatment of women >65 years of age yielded more net benefit than treating no one, provided that the 10–year number–willing–to–treat (NWT) to prevent one cardiovascular event was above 50.                                                                                                                      http://www.mdlinx.com/read-article.cfm/3835678

No comments:

About Me