Menopause Symptoms Not Eased by Calcium, Vitamin D

Supplementation with calcium and vitamin D does not appear to influence the number of menopause-related vasomotor, mood, or sleep symptoms in older women, according to a new study.

A secondary analysis of the Women's Health Initiative Calcium/Vitamin D Supplementation Trial found no difference in the number of menopausal symptoms reported by women randomly assigned to receive elemental calcium carbonate 1000 mg with vitamin D 400 IU daily (CaD) and those reported by the placebo group of the study during approximately 6 years of follow-up.

The findings should not be generalized to all menopausal women, however, because the average age of women at baseline in the current investigation was 64 years, whereas the prevalence of menopause-related hot flashes in particular peaks in women in their early 50s, write Erin S. LeBlanc, MD, MPH, from the Kaiser Permanente Center for Health Research in Portland, Oregon, and colleagues in an article published online June 1 in Maturitas.

In addition, the study looked specifically at prevalence of symptoms, not severity. "[C]onsistent with our a priori analysis plan, we examined whether women had menopausal symptoms, regardless of symptom severity. We were therefore unable to determine if calcium and vitamin D influenced symptom severity such as daily number of hot flashes."

For the study, investigators followed 34,157 women aged 50 to 79 years at 40 clinical sites from the mid­-1990s to 2005, for an average of 5.7 years, and assessed multiple menopausal symptoms, including hot flashes, emotional well­-being, fatigue, and sleep disturbances.

The study's primary outcome was the total number of symptoms, independent of severity, at a given time. Secondary outcomes include the energy/fatigue and emotional well-being subscales of the Short Form 36 Health Survey and a sleep disturbance construct.

Of the study population, 17,101 women were assigned to receive daily calcium/vitamin D supplements, and 17,056 received a placebo.

"Women in the CaD arm did not have a different number of symptoms at follow-up compared to women taking the placebo," the authors report. Specifically, women in the supplement group reported an average of 6.26 menopausal symptoms over the course of the study compared with an average of 6.32 symptoms in the placebo group.

"Similarly, there was no difference between sleep disturbance, emotional well-being, or energy/fatigue at follow-up in those who were randomized to CaD supplementation compared to those taking the placebo," the authors write, noting also that there was no evidence that hormone therapy was an effect modifier of the association between the CaD group and symptoms overall or individual symptoms after adjustment for multiple testing.

The investigators had hypothesized that vitamin D would improve menopausal symptoms via several possible mechanisms, including the mitigation of the menopausal decline in serotonin, which has known effects on thermoregulation and the possible connection between decreasing estrogen and subclinical vitamin D deficiency.