Introduction
Methods of data collection
Dutch health care system
Assessment of cardiovascular disease status at baseline
Source | Data obtained on disease status at study baseline | Data obtained on occurrence of outcomes during follow-up |
---|---|---|
Regular checks of medical records at the GPs’ office | Full medical history | Intercurrent medical history |
Hospital discharge letters | Intercurrent hospital discharge letters | |
Reports on outpatient contacts with medical specialists | Intercurrent reports on outpatient contacts with medical specialists | |
Previous ECGs | Intercurrent ECGs | |
Cause and circumstances of death | ||
Continuous linkage of the study database with GPs’ digital files | NA | ICPC codes of all diagnoses made Date of death |
Home interviews | Medical history | Intercurrent medical history |
Current health status | Current health status | |
Current medication use | Current medication use | |
Research center visits | Resting ECG | Resting ECG |
Physical examination | ||
Pharmacy prescription records | Current medication use | Continous monitoring of all prescriptions filled |
Nationwide Medical Registry (LMR) | History of hospital discharge diagnoses for any outcome of interest | Intercurrent hospitalization with AF or atrial flutter |
Municipality records | NA | Date and place of death |
Hospitals | Hospital discharge letters | Hospital discharge letters |
Previous ECGs | Intercurrent ECGs |
Clinical follow-up
Electrocardiography
Ethics approval
Informed consent
Event adjudication
Definitions of cardiac outcomes
Categories | Underlying outcomes |
---|---|
Coronary heart disease | MI |
Unrecognized MI | |
Myocardial revascularization | |
CHD mortality | |
Overall CHD | |
Heart failure | Heart failure |
Cardiac arrhythmia | Atrial fibrillation and atrial flutter |
Sudden cardiac death |
Coronary heart disease
Myocardial infarction
Unrecognized myocardial infarction
Myocardial revascularization
Coronary heart disease mortality
Mortality categories
(hierarchical) | Underlying cause of death | |
---|---|---|
1. Coronary heart disease | Definite fatal MI | No known nonatherosclerotic cause, and definite MI within 28 days of death |
Definite fatal CHD | No known nonatherosclerotic cause, and at least one of the following: cardiac pain within 72 h of death or a history of ischemic heart disease in the absence of significant valvular heart disease or nonischemic cardiomyopathy | |
Possible fatal CHD | No known nonatherosclerotic cause, and mode of death consistent with CHD in the absence of significant valvular heart disease or nonischemic cardiomyopathy | |
2. Cerebrovascular disease | Nontraumatic intracerebral haemorrhage or infarction | |
3. Other atherosclerotic disease | Atherosclerotic disease other than CHD or cerebrovascular disease (including ruptured abdominal aortic aneurysm, peripheral vascular disease, and visceral vascular disease) | |
4. Other cardiovascular disease | CVD other than 1–3 (including valvular heart disease, nonischemic cardiomyopathy, endocarditis, hypertensive renal disease, pulmonary embolism, ruptured thoracic aortic aneurysm, and complications from cardiovascular interventions other than 1–3) | |
5. Noncardiovascular disease | All other causes of death other than 1–4 (including natural, due to trauma, suicide, and death of unknown or uncertain cause) |