Hormone replacement therapy (HRT) is associated with an increased risk of asthma and wheezing, particularly in lean women, according to a report in the medical journal Thorax.

The findings are based on a study of 8,588 women from Northern Europe who were surveyed between 1999 and 2001. The team excluded women who were pregnant, younger than 46 years of age or using oral contraceptives.

HRT use raised the risk of asthma, wheeze and hay fever by 57 percent, 60 percent and 48 percent, respectively, lead author Dr. F. Gomez Real, from Haukeland University Hospital in Bergen, Norway, and colleagues note. In lean women, however, HRT use more than doubled the risk of asthma and wheeze.

Increasing weight was associated with more asthma symptoms, but only in women who did not use HRT, the report indicates.

Asthma, wheeze and hay fever were not significantly associated with menopause, the authors state.

“Future studies of the effects of HRT on the airways should be conducted in representative general population samples, taking into account the possibility that the effects of estrogens might be dependent on (weight) or metabolic status,” the investigators note.

SOURCE: Thorax, January 2006.