Heart failure affects 26 million people globally. It is a leading cause of hospitalisations and early deaths and is a major economic burden, making up 1-2% of the NHS budget. A common cause is dilated cardiomyopathy, a heart muscle condition that affects up to 1 in 250 people, or 240,000 people in the UK. Unfortunately, despite best
treatment, mortality for this relatively young population (median age 40) remains high. We urgently need to improve how we care for patients with this condition.
Biological sex (being male or female) may play a critical role in disease. My research shows that:
(i) Dilated cardiomyopathy affects twice as many men as women. Either men are more at risk or women are protected.
(ii) The hearts of men and women with dilated cardiomyopathy differ - women have smaller hearts and better heart function.
(iii) Women have a two fold increased risk of complications (admissions to hospital for worsening heart failure) from their disease compared with men with dilated cardiomyopathy, even when we account for heart size and function.
Despite these observations, we currently treat men and women exactly the same.
Women experience a number of unique life events linked to major hormonal changes such as pregnancy, pregnancy complications and menopause. However, we do not know their impact on dilated cardiomyopathy or its complications. Determining how and why dilated cardiomyopathy differs in men and women will help us to make sense of the range of health outcomes that patients experience.
Background: Dilated cardiomyopathy is a leading cause of heart failure, affects up to 1/250 people, and has a 20% 5 year mortality. The contribution of biological sex is poorly understood.
Aim: To evaluate the impact of hypertensive disorders of pregnancy on dilated cardiomyopathy incidence.
Objectives:
1. Evaluate whether hypertensive disorders of pregnancy are associated with an increased risk of developing dilated cardiomyopathy.
Methodology:
1. Cohort study of pregnant women stratified by presence/absence of hypertensive disorders of pregnancy (exposure variable) and followed up for dilated cardiomyopathy development (outcome), analysis using Cox regression. The pregnancy register will be used determine cohort of pregnant women and the CPRD Aurum dataset linked to HES APC data will be used to determine the presence of hypertensive disorders and the outcome of dilated cardiomyopathy.
2. Nested case:control study among women with hypertensive disorders of pregnancy (cases - dilated cardiomyopathy and controls those who have not developed dilated cardiomyopathy), using logistic regression.
Analyses will be adjusted for birth year, age, smoking, parity, multiple pregnancy, prior stillbirth, socio-economic status, as well as post pregnancy diabetes or hypertension, ischemic heart disease, and obesity.
This work will lead to improved understanding of the effect of sex specific variables as cardiomyopathy risk factors to improve diagnostic strategies and identification of previously unrecognised at-risk populations (e.g. women with hypertensive disorders of pregnancy).
Outcome – new diagnosis of dilated cardiomyopathy
Upasana Tayal - Chief Investigator - Imperial College London
Upasana Tayal - Corresponding Applicant - Imperial College London
Constantinos Kallis - Collaborator - Imperial College London
Jennifer Quint - Collaborator - Imperial College London
HES Admitted Patient Care;ONS Death Registration Data;Practice Level Index of Multiple Deprivation;CPRD Aurum Pregnancy Register