Myocardial infarction and stroke during treatment of hypertensive patients with different diuretic regimes
Related Experiment Videos
P J Franks1, P F Bulpitt, K Hartley
1Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, UK.
Insights
Potassium losing diuretics showed no increased cardiovascular risk in a large hypertension study. However, a subgroup analysis suggested a potential increased risk in patients without prior cardiovascular disease.
Area of Science:
- Cardiology
- Pharmacology
- Hypertension Management
Background:
- Diuretics are commonly prescribed for hypertension.
- Potassium-losing and potassium-sparing diuretics are used, sometimes in combination.
- Understanding their comparative safety profiles is crucial for clinical practice.
Purpose of the Study:
- To compare mortality and cardiovascular morbidity between potassium-losing and potassium-sparing diuretic use.
- To investigate potential differences in risk factors and outcomes based on diuretic type.
Main Methods:
- Retrospective analysis of 1,935 hypertensive patients treated between 1971 and 1981.
- Comparison of outcomes between patients receiving potassium-losing diuretics versus those on potassium-sparing diuretics (often in combination).
- Analysis of cardiovascular events (myocardial infarction, stroke) and total mortality, with subgroup analysis excluding patients with prior cardiovascular disease.
Main Results:
- Overall, age-adjusted cardiovascular morbidity and mortality were similar between groups.
- Relative risks for myocardial infarction, stroke, and total mortality did not show statistically significant differences in the overall population.
- In patients without prior cardiovascular disease, potassium-losing diuretics were associated with a threefold increased risk of myocardial infarction (wide confidence intervals) and a trend towards higher male mortality.
Conclusions:
- Potassium-losing diuretics did not demonstrate an increased risk of cardiovascular events or mortality in the overall hypertensive patient cohort.
- An unexplained excess risk of myocardial infarction was observed with potassium-losing diuretics in patients without a history of cardiovascular disease.
- Further investigation is warranted to understand this subgroup finding, considering potential treatment selection bias or chance variation.
Abstract:
A retrospective analysis of mortality and cardiovascular morbidity in patients being treated with a potassium losing diuretic alone or the combination of a potassium losing and sparing diuretic was performed in 1,935 patients attending a hypertension clinic between 1971 and 1981. In all, 713 patients were treated with a potassium losing diuretic and 472 patients were on a potassium sparing diuretic, usually in combination with a potassium loser. Presenting data on risk factors were similar between the two groups and age-adjusted cardiovascular morbidity and mortality was similar between the two groups. The relative risk (RR) for a myocardial infarction event on a potassium losing drug was 1.1 (95% CI 0.5-2.3) in men and 1.0 (0.4-2.5) in women. The corresponding risks for stroke were 0.8 and 0.7 respectively and total mortality was 1.3 and 1.1. However, following exclusion of patients with previous history of cardiovascular disease the risk of myocardial infarction in the potassium losing group was over three times that on a sparing diuretic, though the confidence intervals were wide. Total male mortality tended to be higher (RR = 2.4) but again failed to achieve statistical significance. An excess risk from potassium losing diuretics was found only in patients without cardiovascular disease and cannot be readily explained. This may be the result of treatment selection in different 'at risk' groups or chance in the performance of subgroup analyses.