Flu vaccines associated with 24 percent all-cause death reduction in type 2 diabetes patients

For adults with type 2 diabetes, the benefits of getting a seasonal flu vaccine go beyond avoiding an annoying infection. Vaccine recipients were admitted to the hospital at significantly lower rates for many cardiovascular and respiratory problems and were 24 percent less likely to die of any cause when compared to type 2 diabetes patients who did not get a vaccine.

These results come from a study published in the Canadian Medical Association Journal. Researchers retroactively examined the medical records of almost 125,000 type 2 diabetes patients in England between 2003 and 2010.

They measured rates of hospitalization from stroke, heart failure, heat attack, pneumonia, influenza infection and all-cause death. Overall, researchers recorded about 37,000 hospitalizations from those causes in the seven years, including about 21,000 deaths from any cause. The biggest causes for hospital admissions were influenza or pneumonia infections (about 14,000) and heart failure (about 13,000).

In straight numbers, vaccine recipients had more negative outcomes for hospital admissions due to heart attack and heart failure, which could be explained because vaccine recipients tended to be older and sicker to begin with. They had a lower death rate and similar rates of stroke and pneumonia hospitalizations as the unvaccinated group. They also had higher negative outcomes across all measurements during the summer, considered the flu’s off-season.

But after adjusting the measurements to account for age and disease comorbidity, influenza vaccination was associated with an overall drop in negative outcomes for the factors described. Vaccine recipients were 19 percent less likely to have a heart attack, 30 percent less likely to be hospitalized for stroke, 22 percent less likely to experience heart failure and 15 percent less likely to be hospitalized for pneumonia or influenza. They were a fourth less likely to die from any cause as the group who did not receive a flu vaccination.

Most of the participants were vaccinated annually throughout the study, from 63 percent in the 2008 to 2009 season to 69 percent during the 2006 to 2007 flu season.

The 2009 to 2010 flu season was excluded from the analysis that had the most nuanced adjustment for attenuating factors, because the uptick in flu infections due to the H1N1 pandemic (for which there was no vaccine early in the season) confounded the data.

The researchers set out to find if protecting against that risk for people who already dealt with disease could produce multiplied benefits. Based on these results, the researchers called for continued efforts to bring flu vaccines to more people, especially to populations already at risk who could benefit even more, including type 2 diabetes patients.