Yoga and Vasomotor Symptoms: Does a Meditative Movement Practice Improve Menopausal Symptoms?

By Carrie Decker, ND

Founder and Medical Director, Blessed Thistle, Madison, WI

Dr. Decker reports no financial relationships relevant to this field of study.

Synopsis: In a randomized controlled trial, the implementation of a regular yoga practice was not shown to significantly improve vasomotor symptom frequency or bother at 6 and 12 weeks. However, it was associated with a significant improvement in Insomnia Severity Index.

Source: Newton KM, et al. Efficacy of yoga for vasomotor symptoms: A randomized controlled trial. Menopause 2014;21:339-346.

With the potential health risks associated with hormone replacement therapies for the management of estrogen withdrawal-associated vasomotor symptoms (VMS), the possible use of other medications, herbal supplements, and lifestyle interventions for management of menopausal symptoms continues to be investigated.

Yoga, a mind-body and movement practice, is utilized as an ancillary therapy for a wide variety of chronic diseases including hypertension, pain, depression, sleep disorders, and mental illness.¹ Mechanistically, yoga has been shown in studies to affect endothelial function, inflammation, immune response, salivary cortisol levels, and circulating levels of neurotransmitters and hormones. Having such diverse effects, a variety of broad-scale benefits may be seen. Other studies investigating yoga for the management of menopausal symptoms have shown varying results and have been limited in size or methodology.

This study was a multisite (three sites), randomized, controlled trial using a three-by-two factorial such that all participants had an intervention and therefore an expectation of benefit. The interventions were 12 weeks of yoga, exercise, or usual activity, with simultaneous randomization to 1.8 g/day of omega-3 fatty acid or placebo capsules. Subjects were qualified to participate in the study if they were perimenopausal, postmenopausal, or post-hysterectomy; between 40-62 years old; with follicle-stimulating hormone levels > 20 mIU/mL and estradiol levels of ≤ 50 pg/mL; and were in generally good health. Participants were excluded if body mass index was > 37 kg/m², if hormonal medications or other over-the-counter treatments for VMS had been taken in the past month, or if they currently used one of the interventions being investigated in the study.

A 2-week diary and a questionnaire was used to determine baseline of the primary outcomes of VMS frequency and bother as well as secondary outcomes of sleep quality and disturbance, insomnia severity, depressive symptoms, and anxiety. A 7-day diary was used for assessment of VMS during study weeks 6 and 12, with follow-up questionnaires for other symptoms reassessed only at 12 weeks.

The yoga intervention included specific groups of poses that were identified by expert instructors at the National Center for Complementary and Alternative Medicine to be useful for relieving VMS. Poses were sequenced according to principles of viniyoga. The yoga intervention also included breathing exercises and a deep relaxation meditation called yoga nidra. Instructors were qualified by having 5 years and 500 hours of experience and were instructed in the protocol in a 2-day training session. Individuals in the yoga intervention group participated in a weekly 90-minute class with instruction and were instructed to practice at home for 20 minutes on days they did not attend class. For home practice, they were given a DVD with yoga pose sequences and a CD for yoga nidra. Individuals in the usual activity group were asked to not engage in yoga or change their exercise routines. Comparisons of aerobic exercise were not made with the yoga group and specifics of exercise interventions were not discussed.

Population demographics were not significantly different between groups, with the majority being postmenopausal, well educated (more than 93% educated beyond high school), white (63%), and a mean age of 54 years. For the assessment of the primary outcomes of VMS frequency and VMS bother, a two-sided P value of < 0.025 was considered statistically significant; for the secondary outcomes, a two-sided P value of < 0.0125 was considered statistically significant.

There was no significant difference in VMS frequency at the 6- and 12-week assessment between intervention groups. The change in VMS frequency (mean difference [yoga ¨C usual activity]) from baseline at 6 weeks was -0.3 (95% confidence interval [CI], -1.1 to 0.5) and at 12 weeks was -0.3 (95% CI, -1.2 to 0.6) with P = 0.119 for each. In the yoga group, the baseline mean VMS frequency was 7.4 per day and decreased to 4.6 VMS/day. This compared to the usual activity group with a mean baseline of 8.0 VMS/day, which decreased to 5.4 VMS/day. There also was no significant difference (P = 0.417) in VMS bother with mean bother rating of the yoga group decreasing from 2.9 (1 to 4, with 4 very bothersome) to 2.3 and in the usual activity group from 3.0 to 2.5.

Considering the secondary outcomes of Insomnia Severity Index (ISI), sleep quality and disturbance, depression, and anxiety, a significant improvement was seen in ISI score with a mean change between baseline and 12 weeks for the yoga group of -4.4 (95% CI, -5.4 to -3.4) and -3.1 (95% CI, -3.9 to -2.4) for the usual activity group (P = 0.007). Improvements in sleep quality with yoga intervention compared to usual activity between baseline and 12 weeks (reported by the Pittsburgh Sleep Quality Index) were not significant (P = 0.049) for the criteria of this study. Similarly, improvements in depression with yoga intervention compared to usual activity between baseline and 12 weeks (reported by the Patient Health Questionnaire-8) were not significant (P = 0.028) for the criteria of this study. No significant difference was seen in emergent adverse events in groups at any time point, with no serious adverse events being reported.

When questioned about their experience with the yoga intervention, 68% reported that yoga helped to relieve menopause symptoms and 87% stated that they would like to continue practicing yoga. Adherence to the recommended yoga schedule was monitored and reviewed; participants attended a mean of 8.5 scheduled yoga sessions and practiced at home 4.1 times per week. When analysis of data was limited to women who were at least 80% adherent to the yoga class intervention, the results were not changed.

Reported separately, the intervention of omega-3 fatty acids was not found to have a significant effect on VMS frequency, VMS bother, insomnia, or mood.² Moderate-intensity aerobic exercise was not found to have a significant effect on VMS frequency or VMS bother, but may have a small (non-significant) effect on insomnia, sleep quality, and depressive symptoms.³

COMMENTARY

Other studies assessing yoga for VMS, insomnia, and sleep quality have had study limitations: lacking randomization,^4,5 a non-exercise control group,⁶ or a high drop-out rate.⁷ The limitation of this particular study was that although it was a community-based sample, participants may have been motivated to seek treatment. Additionally, participants were a more educated demographic, were in good health overall, and a low percentage were current smokers. Given these limitations, one might wonder if the implementation of a yoga practice in a more general population may have a more significant effect. However, the practice of yoga does take considerably more time and effort than taking a medication or other supplement. The likelihood of establishing a regular yoga practice is probably quite low for individuals from a general population who are not motivated to seek activities to promote health.

An interesting item to note is that both the yoga and usual activity group experienced a decrease of VMS frequency of > 25% after 12 weeks of the study. Although the difference between these groups was not significant, the fact that such an improvement in VMS was seen in both groups implies that the level of VMS was not stable in individuals recruited for this study, or that VMS generally improves with time. If VMS frequency and bother were more stable for a period of time prior to the study (6 or 12 weeks), the implementation of an intervention may have a different effect. The possibility of a longer study could also be considered; however, a study having a longer duration (4 months) was seen to have a high dropout rate in the intervention group.⁷

Although the effects of omega-3 fatty acids were assessed in a separate publication¹ and were found to not have a significant effect on any parameter measured, half of the individuals in both the yoga and usual activity groups also had the intervention of fish oil. Data were not separately assessed for individuals who were not also a part of the omega-3 fatty acid intervention.

COMMENTARY

Other studies assessing yoga for VMS, insomnia, and sleep quality have had study limitations: lacking randomization,^4,5 a non-exercise control group,⁶ or a high drop-out rate.⁷ The limitation of this particular study was that although it was a community-based sample, participants may have been motivated to seek treatment. Additionally, participants were a more educated demographic, were in good health overall, and a low percentage were current smokers. Given these limitations, one might wonder if the implementation of a yoga practice in a more general population may have a more significant effect. However, the practice of yoga does take considerably more time and effort than taking a medication or other supplement. The likelihood of establishing a regular yoga practice is probably quite low for individuals from a general population who are not motivated to seek activities to promote health.

An interesting item to note is that both the yoga and usual activity group experienced a decrease of VMS frequency of > 25% after 12 weeks of the study. Although the difference between these groups was not significant, the fact that such an improvement in VMS was seen in both groups implies that the level of VMS was not stable in individuals recruited for this study, or that VMS generally improves with time. If VMS frequency and bother were more stable for a period of time prior to the study (6 or 12 weeks), the implementation of an intervention may have a different effect. The possibility of a longer study could also be considered; however, a study having a longer duration (4 months) was seen to have a high dropout rate in the intervention group.⁷

Although the effects of omega-3 fatty acids were assessed in a separate publication¹ and were found to not have a significant effect on any parameter measured, half of the individuals in both the yoga and usual activity groups also had the intervention of fish oil. Data were not separately assessed for individuals who were not also a part of the omega-3 fatty acid intervention.