Absolute benefit, number needed to treat and gain in life expectancy: which efficacy indices for measuring the treatment benefit?
The absolute benefit (AB) is extensively used to summarize the results of clinical trials. As the AB depends directly on the patient's baseline risk, therapeutic decisions based on AB tend to favor patients at high risk. To evaluate the consequences of this decision's procedure for life-long therapy, we compare the AB with the gain in event-free life expectancy in a simulated hypertensive population. Our results show that the AB goes through a maximum and then declines as the duration of treatment increases. The amplitude of the variation of AB is independent of the baseline risks but the maximum is reached more quickly in the high-risk patients. Considering the gain in event-free life expectancy, low-risk patients benefit more than high-risk patients do, at the expense of a longer treatment exposure. The interpretation of the AB changes depending on follow-up.
EA 643/Clinical Pharmacology Unit, Claude Bernard University, Facultá RTH Laennec, Rue Guillaume Paradin BP 8071-69376, Lyon 08, France. bkoupai@ucla.edu
Behrouz
B
Kassai
François
F
Gueyffier
Jean-Pierre
JP
Boissel
Florent
F
Boutitie
Michel
M
Cucherat
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use; D018572:Disease-Free Survival; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy; D008017:Life Expectancy; D015993:Life Tables; D008297:Male; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic / Q000379:methods*; D012107:Research Design; D018570:Risk Assessment; D016896:Treatment Outcome
D000959:Antihypertensive Agents