Heart failure (HF) is a condition where the heart does not pump properly leading to breathlessness, fatigue and fluid retention. Life expectancy following diagnosis is typically 2-3 years. About 2% of the National Health Service (NHS) budget is used to treat HF annually.
Well-conducted clinical studies have shown that compared with HF medication alone, electronic devices (cardioverter defibrillators or cardiac resynchronisation therapy) implanted in the chest to regulate the hearts function, slows deterioration and reduces the risk of death. Coupled with evidence that they also provide reasonable value for money, these devices are currently recommended for particular groups of patients with HF in the NHS. However, little is known about whether the effectiveness and cost savings from these devices, observed in clinical studies, are realised in actual practice.
Primary care, hospital and death data from the Clinical Practice Research Datalink (CPRD) will be used to evaluate patients treated with HF medication alone or with implantable electronic devices. Patients clinical characteristics, HF treatment patterns, compliance with HF medication and factors that determine this, hospitalisation for HF and death will be assessed. The use of health services and associated costs will also be evaluated. Results will be compared with that from other well conducted studies on these devices and will be subsequently used in economic studies to re-evaluate the cost effectiveness of these therapies. Our findings may provide insights on whether data from everyday clinical practice could be used to inform policy decisions about the introduction of HF treatments in the NHS.
Clinical guidance on implantable cardioverter defibrillator and cardiac resynchronisation therapy (ICD/CRT-D) for treating heart failure is largely based on clinical and cost effectiveness evidence from randomised controlled trials (RCTs). However, RCTs may not be representative of HF patients in clinical practice or reflect health service delivery patterns. Primary care data from CPRD, linked to hospital, mortality and deprivation data, will be used to assess heart failure management in practice to re-evaluate economic models on the cost effectiveness of ICD/CRT-D for HF, compared with HF drug therapy alone.
Patients 18 years and older with incident heart failure recorded during 01/01/2008-31/12/2018 will be included. Patients clinical characteristics, HF drug treatment patterns, treatment adherence and its determinants, use of health services and associated costs, rates of hospitalisation, complications, and all-cause, HF and cardiovascular mortality will be evaluated. Clinical characteristics, drug treatment patterns, clinical outcomes and health service use and cost will be presented using appropriate descriptive statistics. Treatment adherence will be assessed using proportion of days covered and medication possession ratio; determinants will be assessed using logistic regression analysis. Hospitalisations per 1,000 patient-years will be estimated and observed cumulative survival will be examined using KaplanMeier survival estimation.
Analyses will also be stratified by relevant subgroups including age-group, gender and HF sub-groups at 3, 6, 12, 24 and 60 months. Estimates will be compared with that from RCTs and other key studies on ICD/CRT-D. The cost effectiveness of ICD/CRT-D will be evaluated as the cost per quality-adjusted-life year gained in economic analysis employing a decision analytic framework and also patient level cost effectiveness analysis. Results from this study and our economic analysis may provide valuable insights on whether data from everyday clinical practice could inform policy decisions about the introduction of HF treatments in the NHS.
- HF treatment patterns (prescription rate, combination therapy, optimal therapy)
- HF treatment adherence
- HF complication rates
- Health care resource use and cost (any cause, and HF-related)
- Hospitalisations (any cause, and HF-related)
- Mortality (All cause, Cardiovascular- related, HF-related)
- Combined end point of hospitalisation or mortality
Puja Myles - Chief Investigator - CPRD
Tarita Murray-Thomas - Corresponding Applicant - CPRD
Alex Bottle - Collaborator - Imperial College London
Martin Cowie - Collaborator - Imperial College London
Reza Skandari - Collaborator - Imperial College London
HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation