By NICHOLAS BAKALAR

The largest and longest clinical trials to date of menopausal hormone therapy have found that the drugs do not increase the risk of premature death.

Researchers writing in JAMA reported the results of two randomized trials. In one, 16,608 women took either a placebo or a combination of estrogen and progesterone for an average of 5.6 years. In the other, 10,739 women took either a placebo or estrogen alone for an average of 7.2 years. The women were 50 to 79 years old.

In an 18-year follow-up, 27.1 percent of the hormone users and 27.6 percent of those who took a placebo, died. Death rates from cancer and cardiovascular disease were the same in each group.

The lead author, Dr. JoAnn E. Manson, chief of the division of preventive medicine at Brigham and Women’s Hospital in Boston, said that “mortality rates are the ultimate bottom line in looking at the net effect of a medication on serious health conditions,” especially with interventions like hormone therapy, which have a complex pattern of risks and benefits.

“The findings provide reassurance to women regarding the use of hormones for menopausal symptoms in early menopause,” she said. “That’s when the symptoms are most severe and impair quality of life, and those are the women who have the most favorable results with hormone therapy.”

Two of the 18 authors have received payments from drug companies.