High blood pressure is one of the most common health problems in the world.
If it is not treated, it can increase the risk of heart attack, stroke, heart failure, kidney disease, and early death.
Medicines are often needed to keep blood pressure under control and protect long-term health.
Two of the most commonly prescribed blood pressure medicines are chlorthalidone and hydrochlorothiazide.
Both belong to a group of medicines called thiazide diuretics, sometimes known as water pills. They help the body remove extra salt and water, which lowers blood pressure.
A large new study led by researchers at Columbia University has compared the safety of these two medicines.
The research followed more than 730,000 people with high blood pressure over 17 years, making it one of the biggest studies ever carried out on these treatments.
The researchers found that both medicines worked well to lower blood pressure and reduce the risk of serious problems such as heart attacks, strokes, and hospital stays for heart failure. However, chlorthalidone was linked to a much higher risk of unwanted side effects.
The biggest difference involved low potassium levels, a condition known as hypokalemia. Potassium is an important mineral that helps the heart, muscles, and nerves work properly. When potassium levels become too low, people may develop irregular heartbeats, muscle weakness, confusion, kidney problems, and a higher risk of type 2 diabetes.
In the study, 6.3% of people taking chlorthalidone developed low potassium levels. By comparison, only 1.9% of people taking hydrochlorothiazide had the same problem. This means the risk was almost three times higher among people using chlorthalidone.
The researchers also found that chlorthalidone users were more likely to develop other electrolyte imbalances and kidney-related problems. These risks remained even when people were taking lower doses of the medicine.
The findings suggest that doctors should carefully consider the possible risks before choosing chlorthalidone. Patients who take this medicine may need closer monitoring, including regular blood tests to check potassium levels and kidney function.
Experts say there is no single best treatment for every patient. The right medicine depends on a person’s overall health, medical history, and risk of side effects. Patients should never stop or change their blood pressure medicine without first speaking with their doctor.
Along with medicine, healthy lifestyle habits remain an important part of controlling high blood pressure. Eating a healthy diet, exercising regularly, limiting alcohol, avoiding smoking, reducing stress, and checking blood pressure at home can all help improve heart health.
The research was led by George Hripcsak and was published in JAMA Internal Medicine. The findings provide important new evidence that may help doctors choose the safest treatment for people living with high blood pressure.
If you care about high blood pressure, please read studies about unhealthy habits that may increase high blood pressure risk, and drinking green tea could help lower blood pressure.
For more information about high blood pressure, please see recent studies about what to eat or to avoid for high blood pressure, and 12 foods that lower blood pressure.
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