Abstract
The protective effect of endogenous estrogen exposure (EEE) duration on hypertension (HTN) risk was shown previously. This study aimed to investigate the effect of EEE on the transitions of different blood pressure (BP) states using a multi-state Markov model. At the study initiation, 2911 normotensive women aged ≥ 20 years were eligible. The Multi-state Markov model, a robust statistical tool, was used to explore the transition probability of various HTN stages, including (I) normotensive to pre-HTN, (II) normotensive to HTN, and (III) pre-HTN to HTN. At the end of the follow-up of 2911normotensive women, 1544 (53%) and 78 (2%) developed pre-HTN and HTN, respectively. The protective effect of EEE duration was observed in all HTN transitions. The most protective effect was observed in transition II [hazard ratio: 0.53; 95% confidence interval (CI): 0.42, 0.66]. Meanwhile, this protective effect in transitions I and III was 11% (95% CI: 0.82, 0.97) and 21% (95% CI: 0.68, 0.91), respectively. Age and family history of HTN were confounding variables that significantly increased the risk of BP progression across all three transitions. An elevated body mass index and a history of diabetes mellitus were found to increase the risk of HTN progression in transition I and II, respectively. The findings indicate that a prolonged duration of EEE was associated with a protective effect against HTN risk across all HTN progression transitions. Furthermore, individuals with shorter EEE durations may warrant closer monitoring due to their elevated risk of transitioning from normotensive to hypertensive states.