Tamoxifen for breast cancer risk reduction: impact of alternative approaches to quality-of-life adjustment on cost-effectiveness analysis.
BACKGROUND
In cost-effectiveness analysis (CEA), the effects of health-care interventions on multiple health dimensions typically require consideration of both quantity and quality of life.


OBJECTIVE
To explore the impact of alternative approaches to quality-of-life adjustment using patient preferences (utilities) on the outcome of a CEA on use of tamoxifen for breast cancer risk reduction.


METHODS
A state transition Markov model tracked hypothetical cohorts of women who did or did not take 5 years of tamoxifen for breast cancer risk reduction. Incremental quality-adjusted effectiveness and cost-effectiveness ratios (ICERs) for models including and excluding a utility adjustment for menopausal symptoms were compared with each other and to a global utility model.


METHODS
Two hundred fifty-five women aged 50 and over with estimated 5-year breast cancer risk >or=1.67% participated in utility assessment interviews.


METHODS
Standard gamble utilities were assessed for specified tamoxifen-related health outcomes, current health, and for a global assessment of possible outcomes of tamoxifen use.


RESULTS
Inclusion of a utility for menopausal symptoms in the outcome-specific models substantially increased the ICER; at the threshold 5-year breast cancer risk of 1.67%, tamoxifen was dominated. When a global utility for tamoxifen was used in place of outcome-specific utilities, tamoxifen was dominated under all circumstances.


CONCLUSIONS
CEAs may be profoundly affected by the types of outcomes considered for quality-of-life adjustment and how these outcomes are grouped for utility assessment. Comparisons of ICERs across analyses must consider effects of different approaches to using utilities for quality-of-life adjustment.
Melnikow
Joy
J
Department of Family and Community Medicine, University of California, Davis, Sacramento, California 95817, USA. jamelnikow@ucdavis.edu
Birch
Stephen
S
Slee
Christina
C
McCarthy
Theodore J
TJ
Helms
L Jay
LJ
Kuppermann
Miriam
M
D018931:Antineoplastic Agents, Hormonal / Q000009:adverse effects / Q000191:economics* / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000191:economics* / Q000517:prevention & control*; D002140:California; D015331:Cohort Studies; D003362:Cost-Benefit Analysis / Q000706:statistics & numerical data; D003657:Decision Making; D005260:Female; D006801:Humans; D008390:Markov Chains; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D040242:Risk Reduction Behavior; D013629:Tamoxifen / Q000009:adverse effects / Q000191:economics* / Q000627:therapeutic use
D018931:Antineoplastic Agents, Hormonal; D013629:Tamoxifen