Stockholm, Jun 24 (IANS): Low levels of a naturally-occurring steroid are tied to an elevated risk of heart and blood-vessel diseases in elderly men, says a new study.

The steroid is DHEA or dehydroepiandrosterone, secreted by the adrenal gland and circulates in the blood mainly as a sulfated form, DHEA-S. In other tissues, DHEA-S is converted into the sex hormones testosterone and estrogen.

In this large-scale study, investigators found that elderly men with the lowest DHEA-S blood levels were significantly more likely than those with higher concentrations to develop cardiovascular-disease within five years.

"Our findings may be the result of DHEA-S being protective, or that lower DHEA-S level is a marker for poor general health," said Asa Tivesten, associate professor at the University of Gothenburg, Sweden, who led the study.

Investigators used an advanced lab technique to isolate, identify, and measure DHEA-S levels in the blood.

During the five-year follow-up, they used nationwide medical registries to document 485 cases of cardiovascular disease among the study participants, according to a Gothenburg statement.

Patients included 2,416 men aged between 69 and 81 years. All were participants in the 'Osteoporotic Fractures in Men' study, which is a long-term project designed to examine risk factors for a number of diseases.

According to Tivesten, this study's findings only indicate that low DHEA-S levels may be related to a greater risk of cardiovascular disease. "We cannot say that DHEA-S is protective because we have only studied an association," she said.

The results will be presented on Saturday at the Endocrine Society's 94th annual meeting in Houston, US.