Abstract
Normal potassium concentrations in the blood (3.5 to 5.1 mmol/L) are important for heart function and rhythm. Abnormal levels outside these limits have been shown to increase mortality from cardiac causes (cardiovascular mortality). Based on the assumption that the potassium concentration might be affected by potassium-influencing drugs, we focused on two specific drug classes with the potential to decrease potassium concentrations in the blood. Firstly, non-potassium-sparing diuretics (such as hydrochlorothiazide, clopamide, chlortalidone, indapamide, furosemide, bumetanide, and torasemide), which are prescription drugs to treat hypertension and heart failure, and secondly, laxatives (such as senna, bisacodyl, picosulfate and others), which are over-the-counter-drugs against constipation.
Our research question was as follows: Do participants with non-potassium-sparing diuretics who additionally use laxatives have a higher risk to die from cardiac causes than those participants without the concurrent use of these two drug classes?
By using the data of 105,359 UK Biobank participants with antihypertensive drug treatment (which includes individuals with hypertension and heart failure) we investigated the associations of separate and combined use of non-potassium-sparing diuretics and laxatives with cardiovascular mortality. Compared to non-users, participants using only non-potassium-sparing diuretics had a 1.4-fold increased risk to die from cardiac causes (Hazard ratio [95%-confidence interval]: 1.37 (1.23; 1.52)), while users of only laxatives showed no statistically significant increased risk [1.19 (0.96; 1.48)]. If users of non-potassium-sparing diuretics additionally took laxatives (concurrent users) they had an even 2-fold increased risk to die from cardiac causes (1.98 (1.43; 2.75).
In conclusion, a drug-drug interaction of non-potassium-sparing-diuretics and laxatives appears plausible. Therefore, physicians are advised to clarify additional laxatives use in patients who use non-potassium-sparing diuretics, and pharmacists should ask patients who regularly purchase laxatives in a pharmacy about non-potassium-sparing diuretics use. Patients should be aware of the risk of concurrent use of these two drug classes, and report both prescription and self-medication drugs to their responsible physicians and pharmacists.
1 Application
Application ID | Title |
21133 | Impact of non-potassium-sparing diuretics and regular laxative use on cardiovascular mortality of subjects receiving anti-hypertensive treatment |
1 Return
Return ID | App ID | Description | Archive Date |
2906 | 21133 | The Associations of Diuretics and Laxatives Use with Cardiovascular Mortality. An Individual Patient-Data Meta-analysis of Two Large Cohort Studies | 1 Dec 2020 |