To test whether common genetic and environmental factors that determine rates of ageing across different organ systems. The longitudinal nature of the study following women through middle age with up to 18 years follow-up will enable us to address how closely changes at one organ or tissue correlate with overall physiological deterioration. The twin study design will allow determination of heritability of the traits, genetic correlations between traits as well as genetic associations with existing genotype information. Sub-studies using the discordant identical twin model will be used to validate and confirm the results, as well as enabling us to adjust for genetic factors in the analysis.
- Cardiovascular: Systolic and diastolic blood pressure and total cholesterol
- Muscle: Body composition, Muscle mass using Hologic QDR 4500/w DXA
- Bone: Bone Mineral Density at hip, spine and whole body
- Respiratory: Lung volumes (FEV1, FVC) from vitalograph
- Vision: Cataract assessment (Scheimpflug lens photograph), Retinal vascular caliber (retinal photograph)