Hepatitis B Vaccination Linked to Reduced Diabetes Risk

The hepatitis B vaccine not only prevents infection but also appears to lower the chances of developing diabetes.

In most countries, infants receive this vaccine routinely, typically as part of a three-dose series. In the US, it was incorporated into vaccination schedules in 1991. By 2018, around 30% of adults were fully vaccinated.

Researchers previously noted that vaccination may decrease diabetes risk. This is related to hepatitis B, which infects the liver and is transmitted through blood, semen, and vaginal fluids – impairing the liver’s ability to manage glucose. Elevated blood sugar levels can lead to diabetes.

However, earlier studies didn’t investigate whether vaccination could lower diabetes risk in individuals who were not infected with hepatitis B.

To address this gap, Nhu-Quynh Phan from Taipei Medical University in Taiwan and her team examined health data from over 580,000 people across the US, Europe, Africa, Latin America, the Middle East, and Asia-Pacific. These records averaged almost four years for each individual, covering the period from 2005 to 2023.

Participants aged 18 to 90 had no types of diabetes and were not infected with hepatitis B. About half were vaccinated, determined by measuring virus-specific antibodies in their blood.

The study revealed that diabetes prevalence among vaccinated individuals was 15% lower than in the unvaccinated group, with most cases being type 2 diabetes, the most prevalent form. The findings will be shared at the upcoming annual meeting of the Diabetes Association in Vienna, Austria.

This observational study also indicated a dose-response correlation. Participants with higher levels of hepatitis B-specific antibodies were less likely to develop diabetes compared to those with lower levels. Variations in antibody levels might correlate with the number of vaccinations received, timing of immunization, or individual immune responses.

No participants were purposefully infected with hepatitis B, suggesting that vaccination not only wards off the virus but may also lower diabetes risk, Fan notes. One explanation could be that vaccines help alleviate chronic inflammation damaging the liver and pancreas, which produce hormones like insulin regulate blood sugar levels.

Nonetheless, researchers cannot dismiss the theory that some protective benefits of vaccines might stem from their role in preventing infections, she adds. They are keen to investigate credible pathways and how mouse models can elucidate distinctions between diabetes types, Fan states.

Vaccinated individuals might also engage in healthier lifestyle choices, such as maintaining a nutritious diet and staying active. “Those likely to get vaccinated often exhibit greater awareness of health,” states Albert Osterhouse from the University of Veterinary Medicine in Hanover, Germany.

The research team considered factors including participants’ age, gender, and lifestyle choices like smoking, along with conditions such as obesity and hypertension. However, Osterhouse emphasizes the difficulty in ruling out the impact of these variables.