Diabetics who attend religious services at least once a year had lower levels of a marker of inflammation linked to heart disease than those who never attended religious services.

However, the authors note that they only measured how often people attended a religious service, and not how religious they were. Furthermore, there appeared to be no link between service attendance and the marker, called C-reactive protein (CRP), in people who were not diabetic.

The benefit of attending services may not be the act of attending services itself, but rather religion's ability to have a positive effect on people's lives, for example by providing a helping community.

Previous research has suggested that elevated blood levels of CRP may be an independent predictor of heart disease. CRP is a protein the body releases as part of its response to infection and injury, and is a known marker of inflammation. During infection, for instance, blood CRP levels temporarily soar as the immune system jumps into action. More subtly, chronic CRP elevations have been linked to an increased risk of heart disease. Inflammation is believed to play a key role in the hardening and narrowing of arteries that can lead to heart attack and stroke.

People with diabetes typically have higher levels of CRP than non-diabetics, a fact that may help explain why diabetics have a higher-than-average risk of cardiovascular problems.

Around 62% of all survey participants said that they attended religious services. The investigators found that diabetics who never attended religious services had a higher risk of having elevated levels of CRP in their blood than attenders.

The link between CRP and religious service attendance remained even when the researchers accounted for of other factors that can affect health, such as smoking, mobility and obesity.

Diabetes Care July 2002;25:1172-1176