High blood pressure is one of the most common health problems around the world. Doctors also call it hypertension. It happens when blood pushes too hard against the walls of the arteries over a long time.
Many people do not notice any symptoms, which is why high blood pressure is often called a silent condition. Even without warning signs, it can slowly damage the heart, brain, kidneys, and blood vessels.
If it is not treated, it can increase the risk of heart attack, stroke, heart failure, kidney disease, and other serious health problems. For this reason, millions of people take medicine every day to keep their blood pressure under control.
Doctors have several kinds of medicines to treat high blood pressure. Two of the most common are chlorthalidone and hydrochlorothiazide. These medicines have been used for many years. They help the body remove extra salt and water through urine.
As the amount of fluid in the blood becomes lower, blood pressure also falls. Because these medicines work in a similar way, many doctors have believed they provide similar benefits. Some treatment guidelines have even suggested that chlorthalidone should be the first choice for many patients.
A large new study now suggests the decision may not be so simple. Researchers from Columbia University examined health records from more than 730,000 adults who were treated for high blood pressure.
The study followed patients over a period of 17 years, making it one of the largest studies to compare these two medicines in everyday medical care. Instead of only looking at how well the drugs lowered blood pressure, the researchers also carefully studied their safety and possible side effects.
The results showed that both medicines lowered blood pressure effectively. However, people taking chlorthalidone were more likely to develop unwanted side effects than those taking hydrochlorothiazide. The biggest difference involved low potassium levels in the blood, a condition called hypokalemia.
Potassium is an important mineral that helps muscles work normally and keeps the heartbeat steady. When potassium levels become too low, people may feel weak, tired, or confused. In severe cases, dangerous changes in heart rhythm can happen and may even become life-threatening.
In the study, 6.3% of people taking chlorthalidone developed low potassium levels, compared with only 1.9% of those taking hydrochlorothiazide. The researchers also found that chlorthalidone was linked with more problems involving the body’s balance of minerals, known as electrolytes, and more problems affecting kidney function.
Healthy kidneys remove waste and extra fluid from the body. When they do not work properly, waste products can build up and serious illness may develop.
The study also suggested that these side effects could raise the risk of kidney failure and type 2 diabetes in some patients. Surprisingly, these problems appeared even when lower doses of chlorthalidone were used.
These findings suggest doctors should think carefully when choosing between these medicines. One drug is not automatically better simply because it has been recommended in the past. Every patient has different health needs.
People who already have kidney disease, low potassium levels, or other medical problems may need extra care when selecting the most suitable medicine. Patients should never stop taking their blood pressure medicine on their own, but they should speak with their doctor if they notice side effects or have concerns about their treatment.
Medicine is only one part of controlling high blood pressure. Healthy habits also play an important role.
Eating less salt, choosing a balanced diet with plenty of fruits and vegetables, exercising regularly, maintaining a healthy weight, avoiding smoking, limiting alcohol, reducing stress, sleeping well, and checking blood pressure at home can all help improve long-term health.
Many people still need medicine even with these lifestyle changes, but healthy habits can make treatment work better and lower the risk of future health problems.
The research was led by Dr. George Hripcsak from Columbia University and was published in the journal JAMA Internal Medicine. The findings remind both doctors and patients that medicines with similar purposes can have different safety profiles.
Careful treatment choices, regular health checks, and open discussions between patients and healthcare providers can help ensure that blood pressure is controlled while reducing the risk of harmful side effects.
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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