Hypertension (high blood pressure) is a common medical condition which increases the risk of serious illnesses including heart attacks, strokes, heart failure and even premature death. The World Health Organization estimates that 40% of adults have hypertension and that 13% of all deaths worldwide are caused by high blood pressure. Using medication to lower high blood pressure reduces the chances of a person with hypertension going on to develop the serious illnesses mentioned above. One commonly used type of blood pressure lowering medications is diuretics (or water tablets). We know that these work to lower blood pressure but we do not know which type of diuretic is best at preventing the serious illnesses associated with hypertension. We will use the CPRD database to identify the large number of patients already being treated with diuretics and followed for up to 30 years. We will compare the effectiveness of one diuretic drug, called indapamide, to another, called bendroflumethiazide, in reducing the risk of heart attacks, strokes, heart failure and death. This will provide evidence to help doctors and patients decide which diuretic to use in the treatment of high blood pressure.
This study aims to compare the effects of prescribing indapamide, a thiazide-like diuretic, with bendroflumethiazide, a thiazide diuretic, as the first-line choice of diuretic in the treatment of hypertension. The outcome measure will be a composite of non-fatal myocardial infarction, acute coronary syndrome, stroke, acute decompensated heart failure or death from cardiovascular causes. We will identify in CPRD all patients aged 18 years and over with first diagnosis of hypertension after 1987. Among them, we will form two groups with first ever prescription of indapamide or bendroflumethiazide. We will follow the groups either to the date of last prescription, date of medication switch, date of additional medication for hypertension (such as beta-blockers, calcium channel blockers, ACE inhibitors, alpha-blockers, ARBs or other antihypertensive medication), date of outcome, date of de-registration with the medical practice or the date of last practice data collection. We will also extract information on patient age, sex, medical practice, co-morbidities, co-prescribed medication, smoking, weight and alcohol consumption. Incidence of event rates will be calculated in each group. Descriptive analysis, and univariate and multivariate Cox regression survival models will be used as appropriate. Subgroup analyses will be implemented for known risk factors. This large population-based study may provide new evidence on the potential benefit of treating hypertensive patients with indapamide or bendroflumethiazide and may inform future clinical trials.
acute decompensated heart failure
- death from cardiovascular causes
- all-cause mortality
- treatment discontinuation, switch or intensification
- diabetes
- hospitalisation
- gout
- hyponatremia
- hypokalaemia
- hip fracture
- renal disease
- dementia
Amy Rogers - Chief Investigator - University of Dundee
Amy Rogers - Corresponding Applicant - University of Dundee
Amy Rogers - Collaborator - University of Dundee
Daniel Morales - Collaborator - University of Dundee
Isla Mackenzie - Collaborator - University of Dundee
Rob Flynn - Collaborator - University of Dundee
Steve Morant - Collaborator - University of Dundee
Thomas MacDonald - Collaborator - University of Dundee
HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation;Practice Level Index of Multiple Deprivation