With commentary by Spyros Mezitis, MD, PhD, endocrinologist and assistant professor of medicine and endocrinology at Weill Cornell Medical College at New York Presbyterian Hospital, New York City; Dan Nadeau, M.D., Dr. Kris V. Iyer Endowed Chair in Diabetes Care and program director, Mary & Dick Allen Diabetes Center, Hoag Hospital, Newport Beach, CA
The flu vaccine does more than help those with type 2 diabetes avoid coming down with influenza. Getting vaccinated also appears to reduce their risk of death, stroke, pneumonia and heart failure, according to a new British study that tracked more than 124,000 adults with type 2 diabetes for seven years.
"Our results show that influenza vaccine may offer substantial additional benefits for people with diabetes because it reduces the likelihood of hospital admission for stroke, heart failure and potentially heart attack," says study leader Eszter Vamos, MD, MPH, PhD, a researcher at Imperial College London.
About 65% of the men and women studied got the flu vaccine—or as the Brits call it, the ''flu jab." In the U.K. recommendations for vaccination are not as universal as in the U.S., according to Dr. Vamos, although those with long-term conditions such as diabetes are urged to get vaccinated.
When the researchers compared the health of those who did get the flu vaccine to those who did not, they found these benefits in the vaccinated:
• 30% less likely to be hospitalized for stroke
• 22% less likely to be hospitalized for heart failure
• 15% less likely to be hospitalized for influenza or pneumonia
• 24% less likely to die during the follow up.
Those who got vaccinated were also 19% less likely to be hospitalized for a heart attack, although the difference between groups was not enough to be statistically significant. The results held even after the researchers took into account other factors, such as age, smoking status and body weight.
Those with type 2 diabetes already have a higher risk of complications related to the flu, Dr. Vamos says. Her study was published July 25 in the Canadian Medical Association Journal.
The findings are no surprise to doctors in the U.S., where influenza vaccination is universally recommended. "We've been giving flu vaccine to all those with type 2 diabetes," says Spyros Mezitis, MD, PhD, an endocrinologist and assistant professor of medicine and endocrinology at Weill Cornell Medical College, New York Presbyterian Hospital in New York City. "We know there is less hospitalization, less cardiovascular disease and respiratory disease," he says. "This study verifies that. And it's a very large study."
Why does the flu vaccine seem to offer this extra protection? Having the flu ''suppresses the immune system and makes the patient, particularly a patient with a chronic disease like type 2 diabetes, at higher risk for all types of respiratory and cardiovascular diseases," Dr. Mezitis says.
Having the flu also ''makes it more challenging to control your diabetes," says Dan Nadeau, MD, the Dr. Kris V. Iyer Endowed Chair in Diabetes Care and the program director of the Mary & Dick Allen Diabetes Center at Hoag Hospital, Newport Beach, CA. For instance, if someone is too sick to eat, he says, their food intake often declines, and that can affect their blood sugar control.
"The best time to get the flu vaccine is when it becomes available in the autumn to build up protection by the start of the flu season," Dr. Vamos says.
In the U.S., the CDC recommends universal routine vaccination each year for anyone six months or older, unless there is a reason not to vaccinate, such as a severe allergic reaction to past influenza vaccines. The vaccination should be gotten by October, if possible, before the season kicks in, the Centers for Disease Control and Prevention (CDC) says. Typically, seasonal flu season can last from October to May, with peaks from December to February, the CDC says. Besides vaccination, staying away from sick people and washing hands frequently can reduce the risk of getting influenza, according to the CDC.