A large new study from Columbia University has revealed important differences between two common drugs used to treat high blood pressure: chlorthalidone and hydrochlorothiazide. The study followed more than 730,000 people over a period of 17 years, making it one of the biggest and longest studies ever done on these medications.
High blood pressure is a very common condition that affects millions of people around the world. If left untreated, it can lead to serious health problems like heart attacks, strokes, heart failure, and kidney disease.
Doctors often prescribe medications to help lower blood pressure and reduce these risks. Chlorthalidone and hydrochlorothiazide are two popular choices. Both are types of “water pills” that help the body get rid of extra salt and water, which can lower blood pressure.
For many years, experts believed that chlorthalidone might be slightly better at preventing heart-related problems. As a result, some guidelines recommended it over hydrochlorothiazide. However, until now, there hasn’t been a clear, large-scale comparison of how safe these two drugs really are when used in everyday life.
The new study found that while both medications work similarly well at lowering blood pressure and preventing heart attacks and strokes, there is a big difference when it comes to side effects. People taking chlorthalidone were much more likely to have serious health problems related to their blood chemistry.
One of the most concerning problems was low potassium levels, a condition known as hypokalemia. Potassium is an important mineral that helps the heart and muscles work properly.
When potassium levels drop too low, it can cause dangerous heart rhythms, muscle weakness, confusion, and in severe cases, even death. The study showed that 6.3% of people taking chlorthalidone developed low potassium, compared to only 1.9% of people taking hydrochlorothiazide.
Even when lower doses of chlorthalidone were used, the risk of low potassium and other problems remained higher. Besides low potassium, chlorthalidone users also had more issues with their kidneys and other electrolyte imbalances. These side effects can sometimes lead to kidney failure or increase the risk of developing type 2 diabetes.
These findings are important because they suggest that hydrochlorothiazide may be a safer choice for many patients, especially those who are older or have other health problems. Doctors might need to be extra careful when prescribing chlorthalidone, making sure to monitor their patients’ blood chemistry regularly.
Managing high blood pressure isn’t just about taking medication. Lifestyle changes are a key part of treatment. Eating a healthy diet, staying physically active, cutting down on salt and alcohol, quitting smoking, and managing stress can all help lower blood pressure.
Checking blood pressure at home and having regular doctor visits are also important to catch any problems early.
This study, led by Dr. George Hripcsak and published in JAMA Internal Medicine, shows why it’s so important to personalize treatment for high blood pressure. Not every drug is right for every person. It also reminds us that even medicines that seem very similar can have big differences in how they affect the body.
As doctors and researchers continue to learn more, patients are encouraged to talk openly with their healthcare providers about the risks and benefits of their medications. Choosing the right treatment can make a real difference in staying healthy over the long term.
If you care about high blood pressure, please read studies about vitamins impacts on high blood pressure people need to know, and how to manage high blood pressure and diabetes with healthy foods.
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