Morbidity analysis at follow-up
Hypertension and peripheral vascular disease were the commonest
conditions to be diagnosed after study entry for both cases and controls
(Table S5). The prevalence of
hypertension was around 10% higher in oestrogen-only users than in
non-users. Osteoporosis was the next most common condition to be
diagnosed in both groups. At follow-up, cases had relatively more
oophorectomies and hysterectomies. The prevalence of most chronic
medical conditions was slightly higher in cases than in the controls,
but there were more missing records in controls than in the cases.
The Kaplan-Meier plots (Figure S3) show that combined HRT users
developed less Type 2 diabetes at all time points over the entire
follow-up period. Until 10 years of follow-up, there were no differences
in heart failure prevalence among the groups. However, after 10 years,
both oestrogen-only HRT users and non-users developed more heart
failure. Both combined HRT and oestrogen-only HRT users developed more
breast cancer than the non-users, but the proportion is slightly higher
in the combined HRT group. There were lower probabilities of
osteoporosis diagnosis among the combined HRT users after 10 years of
follow-up. There was no difference in the probabilities of dementia
diagnosis among all groups up-to 18 years of follow-up. After 18 years,
oestrogen-only HRT users developed slightly more dementia.