In diabetes patients immunization benefits often outweigh the risk

Patients with diabetes have an increased incidence for a number of infections, but vaccine-preventable diseases need not be among them.

“In the risk/benefit category, there’s a lot of potential benefits from these” immunizations, said at the annual advance postgraduate course held by the American Diabetes Association.

Studies have shown that patients with diabetes who are aged 23-59 years have a twofold higher relative risk of acute hepatitis B virus infection, compared with those without diabetes. In addition, the diabetes case fatality rate is more than double, at about five percent.

Individual glucose monitoring has reduced the transmission of hepatitis B virus by contaminated medical equipment, but outbreaks still occur in a variety of settings because of lapses in infection control, said the professor of medicine at George Washington University, Washington.

Still, vaccination rates are no better among patients with diabetes than those without. From 1999-2004 to 2005-2008, vaccination rates inched up only slightly among diabetes patients for both hepatitis A ( 9.3 percent to 15.4 percent) and hepatitis B 15.2 percent to 2.24 percent), according to National Health and Nutrition Examination Survey.

Indeed, a show of hands revealed that less than a dozen of the roughly 500 attendees at the meeting had vaccinated their patients.

“Hepatitis B vaccination is important, but the question is: How do you know whether it works, and how do you monitor it?”

A variety of factors can impair the immunogenicity of the hepatitis B vaccine, including gluteal or intradermal administration, increased age, higher body mass index, and genetics, such as human leukocyte antigen-DR3, which is present in about 95 percent of people with type 1 diabetes.

Unpublished data from the Centers for Disease Control and Prevention suggest that diabetes patients experience a similar drop in seroprotection with age (80 percent at 41-59 years, 65 percent at 60-69 years, and less than 40 percent at 70 years and older).

For patients who fail to respond to the first or second series of vaccinations, based on post immunization serologic testing, higher 40-mcg dose or four dose at zero,one,two, and six months has been shown to improve immunologic response. There is no need, however, to restart a series if it was interrupted, regardless of the duration between vaccinations.

Only about 15 percent of individuals receive the herpes zoster vaccination, approved for persons aged 50 years and older, despite a third of the population expected to develop shingles within their lifetime. The risk is nearly doubled among diabetes patients younger than age 49 years with a hemoglobin A1c exceeding eight percent.

For those who do get vaccinated, however, a small Japanese study reported similar humoral and cellular response three and six months post vaccination among patients aged 60-70 years, with and without diabetes ( J. Infect. 2013; 67:215-9).

One attendee said that Medicare often refuses to cover herpes zoster and hepatitis vaccinations, leading her to remark, “ It’s kind of turning into a class issue. My patients with money will get the vaccine.”

It’s not just Medicare, but a significant number of other insurers who aren’t paying for the vaccines, particularly the pricey $300-$400 zoster vaccine. Much depends on the patient’s insurance plan.

For example, the shingles vaccine is covered by Medicare Part D, but no Part A or Part B, while Medicare Part B covers recipients at “high or medium risk” for hepatitis B, including those with diabetes or end-stage renal disease. At this point, prior authorization is needed for all insurers, including Medicare, and appeals may be necessary.