Determining the incidence and prevalence of pulmonary hypertension associated with common respiratory and cardiovascular comorbidities in the UK

Study type
Protocol
Date of Approval
Study reference ID
24_004140
Lay Summary

Pulmonary hypertension (PH) is a rare but potentially life-threatening condition that affects the blood vessels in the lungs. It develops when the pressure in the blood vessels of the lung is higher than normal. This causes the heart to work harder, which over time can damage the right side of the heart. In severe cases, pulmonary hypertension can lead to death from heart failure within a few years.
While pulmonary hypertension can develop on its own, it more commonly occurs alongside other diseases, including other lung and heart conditions. People who develop pulmonary hypertension alongside other heart and lung diseases - such as left-sided heart failure and chronic obstructive pulmonary disease - are more likely to die at an earlier age than those who have pulmonary hypertension alone.
UK hospital-based data suggest that around 8,000 people develop pulmonary hypertension each year. However, because the condition is often difficult to diagnose and not everyone with pulmonary hypertension is referred to a specialist clinic for treatment, we suspect the actual number of people affected is much higher. This is especially true of people who have pulmonary hypertension with other heart and lung diseases. The aim of this study is to get more accurate information on the numbers of people who fall into this category so that we can design health services that better meet their needs.

Technical Summary

Pulmonary hypertension (PH) describes a heterogeneous population of patients who have a mean pulmonary arterial pressure greater than 20 mmHg. While PH can present as a primary disorder (i.e. idiopathic pulmonary arterial hypertension (iPAH)), it more commonly occurs as part of a complex phenotype associated with other diseases and conditions, including cardiovascular and respiratory comorbidities. Traditionally, and to serve as a guide to treatment, PH has been categorised by WHO into five groups based on the underlying aetiology. While there has been some work undertaken to determine how idiopathic pulmonary arterial hypertension is coded in routine healthcare data, this has been done using hospital as opposed to primary care data. Moreover, few if any studies have explored how other the types of pulmonary hypertension are coded in routine primary care data. Using CPRD Aurum linked with HES APC data, we will develop various algorithms to elucidate how to most accurately determine whether someone has a diagnosis of PH associated with cardiovascular or respiratory diseases (WHO PH Groups 2 and 3). We will then determine the incidence and prevalence of PH overall and by subgroup and how this has changed over time in England.

Health Outcomes to be Measured

Incidence of PH (of any aetiology) new diagnoses per million person-years
Prevalence of PH (of any aetiology) cases per million population (adult)

Incidence of PH associated with left heart disease (WHO Group 2) new diagnoses per million person-years
Prevalence of PH associated with left heart disease (WHO Group 2) cases per million population (adult)

Incidence of PH associated with chronic lung disease (WHO group 3) new diagnoses per million person-years
Prevalence of PH associated with chronic lung disease (WHO Group 3) cases per million population (adult)

Collaborators

Jennifer Quint - Chief Investigator - Imperial College London
Ann Morgan - Corresponding Applicant - Imperial College London
Allan Lawrie - Collaborator - Imperial College London

Linkages

HES Admitted Patient Care