People who attend church regularly often focus on a life to come.

But they also may live longer on Earth, according to a new study.

The study by a University of Pittsburgh researcher found that people who attend weekly religious services have a longer life expectancy. Added years of life were similar to those associated with regular exercise or taking statin-type drugs that lower cholesterol.

The study also suggested that regular church attendance could be more cost-effective, in terms of added years of life, than taking those drugs.

The findings by Dr. Daniel Hall, a general surgery resident at the University of Pittsburgh Medical Center and an Episcopal priest, were published in the March-April issue of the Journal of the American Board of Family Medicine.

In an interview, Dr. Hall suggested that increased longevity among churchgoers could be linked to a number of factors, including an enhanced sense of purpose in life and connection to a "community of support."

Dr. Tony Farah, a cardiologist at Allegheny General Hospital, speculated that other factors might include reduced stress or the impact of church attendance on lifestyle choices, such as smoking cessation or medication compliance. While the study's methodology has limitations, he said the effect of church attendance merits further study.

Dr. Richard Sloan, professor of behavioral medicine at Columbia University Medical Center and author of a forthcoming book, "Blind Faith: The Unholy Alliance of Religion and Medicine," called it a "silly study," in part because doctors can't recommend that people go to church in the same way that they can recommend statin therapy or exercise.

The study acknowledged that there is no evidence that changing attendance at religious services causes a change in heath outcomes. Even if a patient started attending church to get well, "there are ethical, theological and methodological problems" with this approach, the study found.

Dr. Hall noted that the study was intended "primarily as a thought experiment," not for use in clinical decision-making. Still, he defended its conclusions.

He used life expectancy tables to compare the impact of regular exercise, statin therapy and religious attendance and also relied on earlier studies, including a California study that involved questioning thousands of people over time about their attendance at religious services and other behavior.

Dr. Hall said his study focused primarily on attendance at Christian religious services. He also made certain assumptions to compare the cost of various behaviors related to additional years of life.

The average yearly cost of statin therapy-- $836 -- was derived from a published review of usage patterns of six drugs in more than 1,000 managed care plans. The cost of regular exercise was estimated at $500, based on the annual cost of membership at a local gym.

The yearly cost of regular religious attendance was estimated by dividing the average yearly household contribution to religious institutions -- $1,334 -- by the average household size. The study accounted for the fact that some people would pay tithes, following the Biblical directive of offering 10 percent of income to God.

The study found that regular exercise had the biggest effect on longevity, accounting for about three to five additional years of life. It also was the least expensive, costing $2,000 to $6,000 per year of life gained.

Statins were responsible for 2.1 to 3.7 years of life, compared to 1.8 to 3.1 years for regular attendance at religious services.

Taking the cholesterol-lowering drugs, however, was more expensive than going to church. Costs per additional year of life ranged from $4,000 to $14,000 for the drug therapy, compared to an estimated $3,000 to $10,000 for attending religious services.

Besides his work as a surgeon, Dr. Hall is an assisting priest at First Lutheran Church, Downtown, where he plans to preach at this year's Easter vigil service. He said his dual career paths helped to fuel his interest in the research.

Dr. Hall attended Yale University and Yale Divinity School, earning his medical degree from the Yale School of Medicine in 1999. He also completed a three-year fellowship in religion and medicine last year at Duke University Medical Center.

The study was funded in part by a grant from the John Templeton Foundation, which supports research into spirituality.

The foundation also supported a study on intercessory prayer whose findings were released last week.

That study, published in the April issue of American Heart Journal, found that prayers offered by strangers had no effect on whether complications occurred after people had heart surgery. Patients who were certain they would be prayed for also had a higher rate of complications.