Clinical trial NCT02014610: White Blood Cell Counts and Onset of Cardiovascular Diseases: a CALIBER Study
Official title: Leukocyte Counts and Initial Presentation of Cardiovascular Diseases: a CALIBER Study
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Abdominal Aortic Aneurysm
Coronary Artery Disease
Stroke
Heart Failure
Peripheral Arterial Disease
Keywords: Neutrophil
Lymphocyte
Eosinophil
Leukocyte count
Cardiovascular disease
Atherosclerosis
Monocyte
Basophil
Lead sponsor: University College, London
Sponsor class: OTHER
Collaborators: name: Wellcome Trust
name: National Institute for Health Research, United Kingdom
name: Medical Research Council
name: London School of Hygiene and Tropical Medicine
First posted: 2013-12-18
Enrollment: 800000
Sex: ALL
Minimum age (years): 30
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Cohort study of patients in the CALIBER database who have a record of a full blood count (complete blood count) during the study period while registered at one of 225 general practices contributing data to CPRD (the Clinical Practice Research Datalink) and consenting to data linkage.

Brief summary: The complete blood count is a commonly performed blood test, and previous small studies have suggested that the counts of some types of white blood cell in the complete blood count may be related to the onset of cardiovascular diseases such as stroke and heart attack. This is of interest because this information may help to predict strokes or heart attacks and may guide new therapies which act on white blood cells to reduce the risk of cardiovascular disease.

The hypothesis is that counts of particular types of white blood cell are associated with a range of cardiovascular diseases.

Detailed description: There is evidence from epidemiological studies that counts of some types of white blood cell, such as neutrophils, are associated with increased incidence of coronary disease. Associations with other initial presentations of cardiovascular diseases have not been studied in large cohorts, but may be of interest for use in risk prediction or to guide therapeutic strategies.

The aim of this study is to estimate associations between counts of lymphocytes, neutrophils, eosinophils, monocytes and basophils, and initial presentation of a range of cardiovascular diseases.

The study will use data from the CALIBER dataset of clinically collected electronic health record data from England. Patients enter the study when they have a full blood count (complete blood count) recorded in the dataset, and they are followed up until they experience one of the cardiovascular endpoints, death or transfer out of the participating primary care practice.

This study is part of the CALIBER (Cardiovascular disease research using linked bespoke studies and electronic records) programme funded over 5 years from the National Institute for Health Research (NIHR) and Wellcome Trust. The central theme of the CALIBER research is linkage of the Myocardial Ischaemia National Audit Project (MINAP) with primary care (Clinical Practice Research Datalink) and other resources. The overarching aim of CALIBER is to better understand the aetiology and prognosis of specific coronary phenotypes across a range of causal domains, particularly where electronic records provide a contribution beyond traditional studies. CALIBER has received both Ethics approval (ref 09/H0810/16) and ECC approval (ref ECC 2-06(b)/2009 CALIBER dataset).

Eligibility criteria: Inclusion Criteria:

* All patients aged 30 and over, registered with a participating general practice during the study period.

Exclusion Criteria:

* Patients without a measurement of full blood count during the study period.
* Patients with prior atherosclerotic disease, as recorded in primary care or hospitalisation data.

Primary outcomes:
measure: Initial presentation of cardiovascular disease
timeFrame: 10 years
Secondary outcomes:
measure: All cause mortality
timeFrame: 10 years
Other outcomes:
Locations:
Study officials:
affiliation: University College, London
name: Anoop D Shah, MRCP
role: PRINCIPAL_INVESTIGATOR
affiliation: University College, London
name: Harry Hemingway, FRCP
role: STUDY_DIRECTOR
References:
citation: Denaxas SC, George J, Herrett E, Shah AD, Kalra D, Hingorani AD, Kivimaki M, Timmis AD, Smeeth L, Hemingway H. Data resource profile: cardiovascular disease research using linked bespoke studies and electronic health records (CALIBER). Int J Epidemiol. 2012 Dec;41(6):1625-38. doi: 10.1093/ije/dys188. Epub 2012 Dec 5.
citation: Shah AD, Denaxas S, Nicholas O, Hingorani AD, Hemingway H. Neutrophil Counts and Initial Presentation of 12 Cardiovascular Diseases: A CALIBER Cohort Study. J Am Coll Cardiol. 2017 Mar 7;69(9):1160-1169. doi: 10.1016/j.jacc.2016.12.022.
citation: Shah AD, Thornley S, Chung SC, Denaxas S, Jackson R, Hemingway H. White cell count in the normal range and short-term and long-term mortality: international comparisons of electronic health record cohorts in England and New Zealand. BMJ Open. 2017 Feb 17;7(2):e013100. doi: 10.1136/bmjopen-2016-013100.
citation: Shah AD, Denaxas S, Nicholas O, Hingorani AD, Hemingway H. Low eosinophil and low lymphocyte counts and the incidence of 12 cardiovascular diseases: a CALIBER cohort study. Open Heart. 2016 Sep 5;3(2):e000477. doi: 10.1136/openhrt-2016-000477. eCollection 2016.