US researchers have found an association with severe and chronic constipation and kidney disease.Constipation is a common condition, and it can have a variety of impacts on health including raising an individuals' risk of cardiovascular disease, potentially through effects caused by gut bacteria."Our findings highlight the plausible link between the gut and the kidneys and provide additional insights into the pathogenesis of kidney disease progression," said Csaba Kovesdy from University of Tennessee, US.The study showed that individuals with constipation had a 13 per cent higher likelihood of developing chronic kidney disease and nine per cent higher likelihood of developing kidney failure, compared with those without constipation.More severe constipation was linked with an incrementally higher risk for both chronic kidney disease and kidney failure.For the study, the team examined more than 3.5 million US veterans with normal kidney function who were initially examined in 2004 and 2006 and were followed through 2013.Patients' can protect their kidney health by lifestyle modifications and/or use of probiotics, the researchers suggested, adding that the diagnosis and management of constipation might be helpful for preventing or treating kidney disease."The study suggests the need for careful observation of kidney function trajectory in patients with constipation, particularly among those with more severe constipation," Kovesdy noted.The research appears in an upcoming issue of the Journal of the American Society of Nephrology (JASN),