Every year, constipation accounts for 2.5 million visits to the doctor.
Complications are very rare, but chronic, long-lasting constipation can lead to serious health issues.
Previous research has linked constipation to an increased risk of cardiovascular disease, presumably through its effects on intestinal bacteria.
An analysis of over 70,000 women found a 23 percent increased risk of cardiovascular disease in women with severe constipation.
A new study looks at the link between constipation and kidney health.
CKD, kidney failure risk up to 13 percent higher with constipation
Dr. Keiichi Sumida and Dr. Csaba Kovesdy, from the University of Tennessee Health Science Center and Memphis Veterans Affairs Medical Center, examined 3.5 million American veterans. These patients were first seen in 2004 and 2006 and then followed through 2013.
All participants had normal kidney function on their first examination, but as time progressed, some of the patients developed constipation and kidney disease.
Patients with constipation were 13 percent more likely to develop chronic kidney disease (CKD) and 9 percent more likely to have kidney failure.
Researchers also established a proportional association between the degree of severity in constipation and CKD and kidney failure.
Increasingly severe constipation was linked to a higher risk of developing kidney disease.
Dr. Kovesdy points to the link between our intestinal health and our kidneys, suggesting his study sheds light on the causes of kidney disease, as well as treatment and prevention.
"Our findings highlight the plausible link between the gut and the kidneys and provide additional insights into the pathogenesis of kidney disease progression. Our results suggest the need for careful observation of kidney function trajectory in patients with constipation, particularly among those with more severe constipation."
Dr. Csaba Kovesdy
The results will be published in the next issue of the Journal of the American Society of Nephrology.
More research needed to establish causality
According to the Centers for Disease Control and Prevention (CDC), in 2014, more than 20 million people, or 10 percent of the American population, had CKD. Early CKD has no signs or symptoms, so many patients may not be aware they have it.
Dr. Kovesdy adds that further research is needed to see if constipation indeed plays a causal role in developing kidney disease. But if causality is proven, the same lifestyle changes and dietary interventions that help alleviate constipation might also protect patients' kidney health.
Some of the changes in one's diet that can help with constipation include drinking enough water and other fluids, such as vegetable juices and clear soups.
A diet rich in fiber can help with the symptoms, as well as an increased intake of probiotic foods such as yogurt and fermented foods. More exercise and having a daily routine can also help relieve the symptoms.
The progression of CKD can also be slowed down with dietary changes. A diet low in protein and salt has been shown to improve the condition of patients with CKD.
American Society of Nephrology news release, accessed 10 November via EurekAlert.
CDC, Kidney disease, accessed 10 November 2016.
CDC, National chronic kidney disease fact sheet 2014, accessed 10 November 2016.
Constipation and risk of cardiovascular disease among post-menopausal women, Elena Salmoirago-Blotcher et al., The American Journal of Medicine, doi: 10.1016/j.amjmed.2011.03.026, published online 12 June 2011.
National Institute of Diabetes and Digestive and Kidney Diseases, Constipation, accessed 10 November 2016.