HRT could delay onset of dementia

In previous studies researchers have discovered that 20% of women carry a gene which speeds up the ageing process of DNA by up to four times.  The ApoE4 gene leaves women susceptible to age related disease but HRT could protect the DNA and slow ageing.

Dr Natalie Rasgon of Stanford University School of Medicine in California, said, “This shows that the gene is contributing to ageing at the cellular level well before any outward symptoms of decline become apparent.  Yet oestrogen appears to have a protective effect for middle-aged women who are carrying this genetic risk factor.”

The study looked at 70 healthy women between the ages of 45 and 65 and monitored changes in their cells at certain stages.  Over the 2 years the scientists looked at the changes in the cells which protect genetic material from age-related diseases.  The protective cells, known as
telomeres, shorten with age are viewed as a reliable indicator of biological age.

Blood samples were taken from the subjects and it was found that those not on HRT who carried the ApoE4 gene were six times more likely to experience significant shortening of their telomeres.  This could be the equivalent of 10 years of shortening.  Carriers of the ApoE4 gene
who were taking HRT aged at a similar rate to those without the gene.  In those who did not carry the gene, HRT made no difference.

Emily Jacobs, of Harvard Medical School, who worked on the study, said, “It was well known from numerous studies that ApoE4 is a major genetic risk factor for cognitive decline, Alzheimer’s disease and early mortality.”

Dr Simon Ridley, the head of research at Alzheimer’s Research UK, said, “There is mixed evidence surrounding the effects of HRT on Alzheimer’s risk, and some research suggests the timing of HRT may be important. We’d need to see large-scale, long-term trials to know whether HRT can prevent Alzheimer’s.”