High blood pressure is one of the most common health problems around the world. It affects hundreds of millions of people and is a leading cause of heart attacks, strokes, heart failure, kidney disease, and early death.
Because high blood pressure often causes no obvious symptoms, many people do not know they have it until serious damage has already been done. That is why doctors recommend regular blood pressure checks and early treatment when needed.
Medicines play an important role in controlling high blood pressure. Among the most widely used are a group of drugs called diuretics, often known as “water pills.”
These medicines help the kidneys remove extra salt and water from the body through urine. As the amount of fluid in the bloodstream falls, blood pressure also drops, making it easier for the heart to pump blood around the body.
Two of the most commonly prescribed diuretics are chlorthalidone and hydrochlorothiazide. For many years, both have been recommended as effective first treatments because they lower blood pressure well and are inexpensive.
Some treatment guidelines have even favored chlorthalidone because earlier research suggested it might control blood pressure slightly better.
However, a major new study suggests that the choice between these two medicines should not be based only on how well they lower blood pressure. Safety is also an important part of the decision.
Researchers at Columbia University, led by George Hripcsak, studied the health records of more than 730,000 people with high blood pressure over a period of 17 years. This large study allowed the researchers to compare the benefits and risks of the two medicines in everyday medical practice.
The results showed that both medicines were effective at lowering blood pressure. However, people taking chlorthalidone were much more likely to develop certain side effects than those taking hydrochlorothiazide.
The biggest concern was a condition called hypokalemia, which means the level of potassium in the blood becomes too low. Potassium is an important mineral that helps the heart beat normally and supports healthy muscles and nerves.
If potassium levels fall too much, people may develop muscle weakness, tiredness, cramps, irregular heartbeats, confusion, or kidney problems. In severe cases, very low potassium can become life-threatening.
The study found that 6.3% of people taking chlorthalidone developed low potassium levels, compared with only 1.9% of those taking hydrochlorothiazide. In other words, the risk was nearly three times higher among people using chlorthalidone.
Researchers also found that chlorthalidone users experienced more problems with the body’s balance of salts and minerals and had more signs of kidney problems. These increased risks were seen even when patients were taking lower doses of the medicine.
The findings suggest that doctors may need to monitor patients more carefully if they prescribe chlorthalidone. Simple blood tests can check potassium levels and kidney function, allowing doctors to identify problems before they become serious.
Choosing the right blood pressure medicine is rarely the same for everyone. Age, kidney health, other medical conditions, and the medicines a person already takes all affect which treatment is most suitable.
For many patients, hydrochlorothiazide may provide similar blood pressure control with fewer side effects, although some people may still benefit from chlorthalidone under careful medical supervision.
Medicine is only one part of controlling high blood pressure. Healthy lifestyle habits remain very important.
Eating less salt, enjoying plenty of fruits and vegetables, staying physically active, maintaining a healthy weight, avoiding smoking, limiting alcohol, reducing stress, and checking blood pressure regularly can all help lower blood pressure and reduce the risk of heart disease.
The researchers say their findings support a more personalized approach to treatment. Instead of assuming one medicine is best for everyone, doctors should carefully balance the benefits and risks for each individual patient.
The study was published in JAMA Internal Medicine and was led by George Hripcsak and colleagues at Columbia University. It provides valuable evidence that while both medicines lower blood pressure effectively, hydrochlorothiazide may be the safer option for many people because it causes fewer serious side effects.
If you care about high blood pressure, please read studies that early time-restricted eating could help improve blood pressure, and natural coconut sugar could help reduce blood pressure and artery stiffness.
For more health information, please see recent studies about added sugar in your diet linked to higher blood pressure, and results showing vitamin D could improve blood pressure in people with diabetes.
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