Our Current Understanding of Readmissions
It is well established that patients with heart failure are at least twice as likely to be admitted for in-hospital patient stay and treatment than their age-matched population controls without heart failure. Whilst the pattern of admission and readmission for this patient population is understood, there is a gap for actionable technologies to optimise medical or pharmacological treatment, with current intervention strategies not significantly reducing readmission and mortality outcomes for this patient population.
The literature and clinical publications suggest that the readmission picture has not dramatically improved in the last decade due to treatment strategies not aligning with the factors driving the initial hospitalisation event. Recent studies have shown many factors related to readmissions following a CHF event.
Many factors are well-documented and are commonly present in re-hospitalised patients. Others are less recognised or understood and are associated with higher or lower readmission rates. Although not exhaustive, this section details some of these associations and is the subject of multiple studies and research interests.
Factors Increasing Readmission
Comorbidities – The most apparent causes for readmission relate to increased cardiac and non-cardiac comorbidities across every demographic. Many HF trials fail to report baseline comorbidity rates, resulting in a lack of valuable data. Major comorbidities include:
- Diabetes is on the rise globally, particularly in low and middle-income countries. Nevertheless, it doubled over the last 15 years in developed countries such as the UK – increasing by 150,000 people between 2020 and 2021.
- Obesity is one of the largest recognised epidemics, and over 35 million adults (more than 50%) in the UK are overweight or obese, increasing in number and proportion yearly.
- Hypertension affects over 25% of the population, with the least privileged populations being at least 30% more likely to have high blood pressure.
- Atrial Fibrillation (AF) prevalence is rising globally, and AF is a significant risk factor for Congestive Heart Failure (CHF). Yet it can be a consequence of worsening CHF and autonomic changes resulting from increased congestion.
- Chronic Kidney Disease (CKD) is commonly associated with the development of heart failure, with the risk of CKD also increasing significantly with age.
- Arterial Stiffness is an independent prognostic indicator of CHD and can be caused by calcification or a reduced elastin/collagen ratio.
- An ageing population – Many comorbidities listed have significant risk increases with age. 8% of people were 75 or above in 2018, which is expected to increase to 13% by 2043. As people are living longer, comorbidities are becoming more prevalent.
As well as these factors, which are linked to increased risk of readmission, there also exist several predictors and causes of HF events common to admission and readmission rates alike. An additional subset of cardiac events during the index admission are predictive events to the increased chances of readmission of patients with heart failure.
Predictive factors
This is not an exhaustive list, but it covers many of the main attributing factors of HF readmission rates and the most understood predictors of readmission.
- Ejection Fraction – when reviewing clinical evidence into the measures to reduce HF-related readmission rates, there is often a measured decrease in readmission rates among HF patients with preserved ejection fraction (HFpEF). However, there is often no such reduction in HF-related readmission rates for HF patients with reduced ejection fraction (HFrEF), consistent with extensive population studies.
- Percutaneous Coronary Intervention (PCI) – Patients with new-onset or chronic heart failure who have undergone stents or other percutaneous interventions are at high risk of readmission. However, many of these readmissions are for angina symptoms that do not turn out to be myocardial infarctions and are a confounding factor in the rates of readmission in this sub-group
- Longer QRS duration – Post-admission cardiac monitoring has increased readmissions relating to a longer duration of the patient’s QRS. As QRS duration is considered a predictor (or pre-marker) of ventricular mechanical dysfunction, this has become a target of resynchronisation therapy treatment such as Cardiac Resynchronization Therapy (CRT) and Physiological pacing to reduce readmission.
- Socioeconomic factors – The deprivation and healthcare affordability often result in the least affluent and ethnic minority groups being affected the most by HF readmissions.
- Non-manual work – To a lesser extent, a sedentary lifestyle and lack of self-care after discharge increase readmission rates.
- High volume hospitals – Hospital volume is a marker of quality of care as larger institutions can often have limited resources available per patient. Readmission rates are highest in high-volume hospitals; therefore, hospital administrators are planning for the provision of specialist care as critically important to meet readmission reduction targets.
Once the drivers of increased readmission rates are better understood and categorised, it becomes apparent that a handful of related pathologies with common causes can be treatment targets. However, evidence suggests some contributing factors to the reduction of readmission rates for HF patients existing on the level of care provision and planning of Hospital care deployment.
In the next post of the “Redefining Heart Failure” blog series we’ll be exploring “How to Reduce Heart Failure Readmission” – sign up to our newsletter below to get notified when it is released.