Hormone Replacement Therapy and the Risk of Coronary Heart Disease
- Consider a woman in her 50s experiencing menopausal symptoms like hot flashes and mood swings.
- Her doctor suggests hormone replacement therapy (HRT) to ease these symptoms.
- But then she hears that HRT might increase her risk of coronary heart disease (CHD).
- Confused, she wonders: Is HRT safe?
What is Hormone Replacement Therapy (HRT)?
Definition
Hormone replacement therapy (HRT)
HRT is a treatment that supplements the hormones oestrogen and progesterone, which naturally decline during menopause.
- It helps alleviate symptoms such as:
- Hot flashes and night sweats
- Mood swings
- Vaginal dryness
- Reduced sex drive
- Bone weakening (osteoporosis)
HRT can be administered as pills, patches, gels, or creams, tailored to individual needs.
Early Studies Suggested A Promising Correlation
- In the 1980s and 1990s, epidemiological studies suggested that women using HRT had a lower incidence of CHD.
- This led to the belief that HRT might protect the heart and became a widely accepted idea in the medical community.
Researchers observed that women on HRT seemed to have fewer heart attacks compared to those who didn't use the therapy.
Randomized Controlled Trials Indicated Slight Increases in CHD Risk
- Later, randomized controlled trials (RCTs) the gold standard in research revealed a different story.
- These studies showed that HRT was actually associated with a slight increase in CHD risk.
The Women's Health Initiative (WHI) study found that women on combined HRT (oestrogen and progesterone) had a higher risk of heart disease compared to those on a placebo.
Correlation is Not Causation: Lessons from Early HRT Studies
- The discrepancy between early studies and RCTs highlighted a key concept: correlation does not equal causation.
- Early studies did not account for confounding factors that influenced the results.
