Continuing screening mammography in women aged 70 to 79 years: impact on life expectancy and cost-effectiveness.
BACKGROUND
Mammography is recommended and is cost-effective for women aged 50 to 69 years, but the value of continuing screening mammography after age 69 years is not known. In particular, older women with low bone mineral density (BMD) have a lower risk of breast cancer and may benefit less from continued screening.


OBJECTIVE
To compare life expectancy and cost-effectiveness of screening mammography in elderly women based on 3 screening strategies.


METHODS
Decision analysis and cost-effectiveness analysis using a Markov model.


METHODS
General population of women aged 65 years or older.


METHODS
The analysis compared 3 strategies: (1) Undergoing biennial mammography from age 65 to 69 years; (2) undergoing biennial mammography from age 65 to 69 years, measurement of distal radial BMD at age 65 years, discontinuing screening at age 69 years in women in the lowest BMD quartile for age, and continuing biennial mammography to age 79 years in those in the top 3 quartiles of distal radius BMD; and (3) undergoing biennial mammography from age 65 to 79 years.


METHODS
Deaths due to breast cancer averted, life expectancy, and incremental cost-effectiveness ratios.


RESULTS
Compared with discontinuing mammography screening at age 69 years, measuring BMD at age 65 years in 10000 women and continuing mammography to age 79 years only in women with BMD in the top 3 quartiles would prevent 9.4 deaths and add, on average, 2.1 days to life expectancy at an incremental cost of $66773 per year of life saved. Continuing mammography to age 79 years in all 10000 elderly women would prevent 1.4 additional breast cancer deaths and add only 7.2 hours to life expectancy at an incremental cost of $117689 per year of life saved compared with only continuing mammography to age 79 years in women with BMD in the top 3 quartiles.


CONCLUSIONS
This analysis suggests that continuing mammography screening after age 69 years results in a small gain in life expectancy and is moderately cost-effective in those with high BMD and more costly in those with low BMD. Women's preferences for a small gain in life expectancy and the potential harms of screening mammography should play an important role when elderly women are deciding about screening.
Kerlikowske
K
K
Department of Epidemiology and Biostatistics, Department of Veterans Affairs, University of California, San Francisco 94121, USA. kerliko@itsa.ucsf.edu
Salzmann
P
P
Phillips
K A
KA
Cauley
J A
JA
Cummings
S R
SR
D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density; D001943:Breast Neoplasms / Q000453:epidemiology / Q000517:prevention & control; D002278:Carcinoma in Situ / Q000453:epidemiology / Q000517:prevention & control; D018270:Carcinoma, Ductal, Breast / Q000453:epidemiology / Q000517:prevention & control; D003362:Cost-Benefit Analysis; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D008017:Life Expectancy; D008327:Mammography / Q000191:economics* / Q000706:statistics & numerical data*; D008390:Markov Chains; D019057:Quality-Adjusted Life Years; D012680:Sensitivity and Specificity