Flu season may play a role in kidney failure deaths

TEXAS: When influenza-like illnesses spread in the community, death rates go up for patients on dialysis, a new study shows.

In an average year, severe respiratory infections likely contribute to more than a thousand deaths among people with end-stage kidney failure in the U.S., the authors estimate.

Senior author Dave Gilbertson of the Minneapolis Medical Research Foundation in Minnesota and colleagues suspected that patterns of deaths in these patients might be linked at least to some extent with seasonal fluctuations in flu-like illnesses. To study the issue, they looked at data from the U.S. Centers for Disease Control and Prevention for the years 2000 to 2013.

Compared to patterns in summers, an estimated 1 percent increase in flu and flu-like illness in the fall was associated with a 1.5 percent increase in deaths among kidney failure patients. And in winter, an estimated 1 percent increase in these respiratory infections was associated with a 2 percent rise in kidney patient deaths.

Flu-like illnesses may not be the direct cause of death in these cases but may contribute to other causes of death, Gilbertson told Reuters Health in an email.

For example, he said, flu-like illnesses can induce acute inflammation, making people with kidney failure vulnerable to other infections or even to cardiovascular events.

Flu vaccines, protective barriers such as masks and increased disinfection of dialysis units during flu season could help protect kidney failure patients from potentially deadly influenza-like illnesses, the researchers write in the Journal of the American Society of Nephrology.

These illnesses disproportionately affect vulnerable populations, such as the elderly, and those with chronic diseases like kidney failure, they point out.

Many such patients have impaired immune function and so vaccines may be less effective for them.

That’s part of the reason why experts recommend preventive actions not just for patients at high risk but for healthcare workers, family members and other household contacts as well.

Flu-like illnesses may be caused by a wide array of viruses, including rhinovirus and adenovirus, but influenza itself still accounts for 10 to 50 percent of cases, the authors write.

Dr. Albert Wu, an internist and professor of health policy and management at the Johns Hopkins Bloomberg School of Public Health in Baltimore, said the study is a reminder that many respiratory infections other than flu can be deadly.

Wu, who was not involved in the study, said the results reinforce the importance of basic infection control.

The findings, say the researchers, “suggest that protection against, surveillance of, and, where possible, treatment of infections due to influenza and related viral respiratory illnesses may constitute an opportunity to reduce deaths in patients with end-stage renal disease.”