by Bruce Sylvester – Researchers report that respiratory symptoms vary significantly in different stages of the menstrual cycle, and that there are more symptoms during the mid-luteal to mid-follicular stages.
The findings were published online on Nov. 9, 2012 in the American Journal of Respiratory and Critical Care Medicine.
“The effects of the menstrual cycle on respiratory symptoms in the general population have not been well studied,” said lead author Ferenc Macsali, MD, of the Haukeland University Hospital in Bergen, Norway. “In a cohort of nearly 4,000 women, we found large and consistent changes in respiratory symptoms according to menstrual cycle phase, and, in addition, these patterns varied according to body mass index [BMI], asthma, and smoking status.”
The investigators enrolled 3,926 women with regular cycles who were not taking exogenous sex hormones. They tracked menstrual cycles, respiratory symptoms, BMI, asthma, and smoking status by postal questionnaire.
They reported significant variations over the menstrual cycle for each symptom assessed.
Wheezing was higher on cycle days 10-22 in most subgroups, with a drop near the putative time of ovulation (~days 14-16). Shortness of breath was highest on days 7-21 in most subgroups, with a drop prior to mid-cycle. Incidence of cough was higher just following putative ovulation for asthmatics, subjects with BMI ≥ 23kg/m2, and smokers, or just before ovulation and the onset of menses in subgroups with a low incidence of symptoms.
“Our finding that respiratory symptoms vary according to the stage of the menstrual cycle is novel, as is our finding that these patterns vary according to BMI and smoking status,” said Dr. Mascali. “These relationships indicate a link between respiratory symptoms and hormonal changes through the menstrual cycle.”
The authors noted that study had limitations, including the use of questionnaires to gather data and variation in the length of menstrual cycles in the study population.
“Our results point to the potential for individualizing therapy for respiratory diseases according to individual symptom patterns,” concluded Dr. Mascali. “Adjusting asthma medication, for example, according to a woman’s menstrual cycle might improve its efficacy and help reduce disability and the costs of care.”