This study is an extension of a recent US study that retrospectively analysed data on adult patients in the Yale-New Haven Health System.1 The aim is to adapt this study design for an English context and use CPRD Aurum to identify patients with markedly elevated blood pressure and characterise their follow-up care pattern. The authors of the original study are collaborators on this project.
This is an observational follow-up study of a random sample of adults aged under 80 with at least one markedly elevated blood pressure reading recorded during the study period (January 2015 to March 2020). Using an open cohort design, we will identify and follow-up two groups of patients: Group 1 - patients with at least 1 systolic blood pressure (SBP) ≥160 mm Hg or diastolic blood pressure (DBP) ≥100 mm Hg and Group 2 - patients with at least 1 systolic blood pressure (SBP) ≥180 mm Hg or diastolic blood pressure (DBP) ≥120 mm Hg (a subset of group 1 patients with a more extreme phenotype).
For each group, we will describe: 1) how often these patients have timely subsequent visits (within 1, 3 and 6 months), and 2) how commonly they ultimately achieve guideline-based blood pressure control targets (within 3, 6 or 12 months). We will also describe the median duration between the first measurement of elevated blood pressure and 1) a follow-up visit and 2) achievement of control target. A focus of the analysis will be to examine how these indicators vary by patients’ socio-economic characteristics (age, sex, geographic region, ethnicity and deprivation) and clinical factors (BMI, smoking status, hypertension diagnosis, selected comorbidities).
Primary outcome:
Number and percentage of patients who had at least 1 markedly elevated reading of systolic blood pressure [SBP] ≥160 mm Hg or diastolic blood pressure [DBP] ≥100 mm Hg who have a subsequent blood pressure reading recorded within 1, 3, 6 or 12 months (overall and in subgroups of age, sex, IMD quintile, geographic region and ethnicity). A sub-group analysis will be performed out with a subset of patients with a more extreme phenotype (SBP ≥180 mm Hg or DBP ≥120 mm Hg).
Secondary outcomes (overall and in subgroups of age, sex, IMD quintile, geographic region and ethnicity):
Number and percentage of patients who reach BP control target (recorded SBP <140 mm Hg and DBP <90 mm Hg) within 3,
6 or 12 months.
Median durations between the first measurement of elevated blood pressure and follow-up visit
Median duration between the first measurement of elevated blood pressure and control target achievement.
The number of markedly elevated SBP or DBP measurements during the study period (adjusted for length of follow-up)
Hannah Knight - Chief Investigator - The Health Foundation
Yannis Kotrotsios - Corresponding Applicant - The Health Foundation
Anne Alarilla - Collaborator - The Health Foundation
Jay Hughes - Collaborator - The Health Foundation
Mai Stafford - Collaborator - The Health Foundation
HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation;Practice Level Index of Multiple Deprivation Domains