Study Reveals: Constipation May Increase Risk of Heart Events Including Heart Disease

Constipation, a common digestive issue, often leaves people feeling bloated and discomforted. However, recent research has found that it may be linked to more severe and unexpected health consequences—significant heart events.

The study revealed that individuals with constipation have a higher risk of developing severe cardiovascular diseases such as heart disease and stroke, especially when accompanied by hypertension. This discovery has garnered widespread attention in the medical community, as traditionally, factors like hypertension, obesity, and smoking have been considered the primary inducers of heart disease. However, Francine Marques, Ph.D., the head of the Hypertension Research Group at Monash University, noted that these factors alone cannot fully explain the occurrence of major heart events. She told Health magazine that the gut microbiome has now emerged as a known risk factor for heart disease, and constipation can impact it.

Although this is not the first study to uncover a link between constipation and cardiovascular events, experts believe that more research is needed to delve deeper into the relationship between the two. However, scientists have already gathered some crucial information that may help us better understand the connection between constipation and heart health.

In recent years, there has been mounting evidence suggesting a close relationship between the gut microbiome and heart health. This discovery has prompted scientists to investigate how constipation might affect heart health. For instance, a 2023 study found a "suggestive causal relationship" between constipation and atrial fibrillation, the most common type of arrhythmia. However, not all studies have drawn the same conclusions. Another study conducted in the same year found that hospitalized patients aged 60 and above with constipation and hypertension had a higher risk of experiencing all cardiovascular events.

Against this backdrop, researchers conducted more in-depth studies. In the latest study published in the American Journal of Physiology-Heart and Circulatory Physiology, scientists analyzed data from over 400,000 individuals aged 40 to 69 in the UK Biobank, a large biomedical database and research resource. They reviewed medical records, surgical histories, and death registration data to identify associations between constipation and major adverse cardiac events (MACE), such as heart failure, ischemic stroke, or acute coronary syndrome. Constipation was defined as regular use of laxatives or being documented in hospital medical records or irritable bowel syndrome questionnaires.

After adjusting for age, gender, BMI, use of medications that may cause constipation, smoking status, and health conditions such as high cholesterol and diabetes, the research team found that individuals with constipation had a two to three times higher risk of experiencing severe adverse cardiac events compared to those with normal bowel habits. The study also showed that constipation in hypertensive patients increased the risk of heart events by about 1.7 times.

The study also found a 21% to 27% association between constipation and genetic risk factors for cardiovascular diseases. The authors believe that this could partially explain the link between the two. For example, certain genes may cause disruptions in the autonomic nervous system, which regulates cardiovascular and gastrointestinal functions. Additionally, studies have speculated that straining during bowel movements could cause blood pressure to spike, potentially leading to cardiovascular events over time.

However, despite the new research revealing a possible link between constipation and heart problems, experts emphasize that no studies have yet confirmed a definitive causal relationship between the two. Timothy Ritter, M.D., a gastroenterologist, said that there is definitely no causal relationship between the two. Patients with constipation may have other diseases that put them at higher risk of cardiovascular diseases. Furthermore, the study has some limitations, such as only including participants of European white ancestry, and some data being self-reported—therefore potentially inaccurate. Ritter told Health magazine that the definition of "constipation" is not clear: whether people are "using laxatives every day during menstruation or only once a month."

Mary Branch, M.D., a cardiologist in Greensboro, North Carolina, noted that the intermittency of constipation also makes it difficult to assess its relationship with heart health. "So, if you're trying to find a connection with outcomes that are so fleeting and not a definitive disease state," she told Health magazine, "then drawing conclusions can become a bit messy."

So, how should we respond to this research finding? Dr. Branch said that since the research is still ongoing, it's hard to know whether regulating constipation can help reduce the risk of cardiovascular diseases. However, she pointed out that there is a clear connection between the gut microbiome and cardiovascular diseases because the gut microbiome plays a role in controlling inflammation. "Fiber can improve gut function, help us avoid constipation, and also improve blood pressure, reducing the risk of heart disease," said Marques. "We recommend that people increase their intake of dietary fiber, regardless of whether they have constipation, because most people are deficient in fiber."

Dr. Branch also recommended following the guidelines of the American Heart Association and prioritizing overall heart health. This means adhering to physical exercise, following a diet rich in natural foods, prioritizing sleep, controlling cholesterol, and quitting smoking.

In conclusion, although the link between constipation and heart health still needs further research to confirm, maintaining a healthy lifestyle is undoubtedly an important measure to prevent cardiovascular diseases.