Sex Hormones in Older Women (SHOW)
Cardiovascular disease (CVD; heart attack and stroke) is the leading cause of death in women aged 65 years and over. The risk of CVD increases steeply after midlife, implicating both age and possibly hormonal changes with ageing as playing a role.
The major sex hormones in women are oestrogens and androgens (such as testosterone). Oestrogen levels fall suddenly at menopause. Androgen levels do not change at menopause but start to fall from the mid 30’s, and then decline steadily with age until the 7th decade, after which testosterone levels start to increase.
There are some indications that low levels of testosterone may be associated with an increased risk of CVD in women, however this is still to be proven. Previous studies have been small, often conflicting and lacking the precision to accurately measure low concentrations of testosterone seen in older women.
The SHOW Study is investigating the association between levels of androgens (testosterone and other androgens) in the blood and cardiovascular events and life expectancy in older women.
This study will also provide for the first time, a reference range for blood levels of the various androgens in women aged 70-74 years, 75-79 years, 80-84 years and 85+ years.
In the future, SHOW may also be able to investigate associations between sex hormones and other ASPREE outcomes such as fracture, cognitive function and cancer.
What participation involved
The SHOW sub-study utilised existing health information and blood samples volunteered to the principal ASPREE trial and ASPREE Healthy Ageing Biobank. Participants did not need to do anything more than continue in the ASPREE trial as normal.
Researchers measured androgen and oestrogen hormone levels in approximately 6,200 blood samples donated by female ASPREE participants to the Healthy Ageing Biobank shortly after they enrolled in the ASPREE trial (baseline). Hormone levels were tested in approximately 450 blood samples that had been provided to the biobank three years later.
Because ASPREE participants shared health information, researchers will be able to determine the association between androgen hormone levels and CVD risk in older Australian women.
The SHOW sub-study is led by the Women’s Health Research Program, Monash University and was conducted in Australia. The first two papers have been published.
For more information about ASPREE-SHOW:
- Ring 1800 728 745 (toll free from a landline)
SHOW Principal Investigators:
- Women’s Health Research Program, Monash University
- ANZAC Research Institute, University of Sydney
- GP Associate Investigators
- The Australian National Health and Medical Research Council (NHMRC) grant $594,672.40