“To our knowledge, this is the first study that has looked across different modalities of mind-body interventions and the first to show that there is a very consistent effect on [A1c] regardless of which modality you use,” senior author, Richard Watanabe, PhD, professor of biostatistics, Keck School of Medicine of the University of Southern California, Los Angeles, told Medscape Medical News.
“[Because] our study showed that it doesn’t matter which type of intervention patients do, it’s really up to the physician to work with their patients and help them pick something that works for them,” he added.
“Thus, this really is a much more flexible tool than having to tell a patient they should do yoga if their schedule doesn’t allow them to do yoga. There are other options available, so if you are a busy person and getting yourself to a yoga session is not doable, take a little time to learn about meditation and you can do it anywhere,” he said.
The study was published online in the Journal of Integrative and Complementary Medicine by Fatimata Sanogo, PhD candidate, also of Keck School of Medicine, USC, and colleagues.
Regularity of Yoga Practice Makes the Difference
A total of 28 studies of patients with type 2 diabetes published between 1993 and 2022 were included in the meta-analysis. In all studies, patients who were taking insulin or had any medical complications of diabetes were excluded.
A significant mean reduction in A1c of 0.84% was observed across the board for all types of mindfulness interventions (P < .0001).
For mindfulness-based stress reduction, A1c was reduced by 0.48% (P = 0.03), while the practice of qigong — a coordinated body-posture movement — was associated with a 0.66% drop in A1c (P = .01). For meditation, A1c dropped by 0.50% (P = .64).
However, the largest drop in A1c was seen with yoga where it fell by 1.00% (P < .0001) — about the same degree of glycemic control achieved with metformin, the authors point out.
Indeed, for every additional day of yoga practiced per week, mean A1c differed by –0.22% (P = .46) between those who engaged in mind-body interventions and those who did not.
There was also a reduction in fasting blood glucose (FBG) with yoga and other practices. “The mean change in FBG was consistent with the mean change in A1c at –22.81 mg/dL (P < .0001),” the authors continue.
The researchers found that the duration of yoga didn’t matter but the frequency did, so it’s the regularity “with which you do yoga that makes the difference,” Watanabe said.
Watanabe and his coauthors also point out that because most patients were actively receiving metformin before and throughout the studies, the observed effect of mind and body practices on A1c represents an additional reduction beyond that of medication.
“This raises the question [as to] whether mind and body practices could be useful when initiated early in the course of diabetes therapy along with conventional lifestyle treatments,” they suggest.
While more research is needed to study this specifically, “our results suggest that these mind-body practices might be a good preventative measure,” Watanabe noted. Mind-body practices may also effectively prevent type 2 diabetes in at-risk patients, the authors propose.
Does Meditation Help Alleviate Psychological Distress?
How mind-body practices work to improve glycemic control isn’t clear but one possible theory is that patients experience a decrease in psychological distress when they undertake such practices, and in so doing, may be more compliant with their prescribed treatment regimen.
A few of the studies analyzed showed that mind-body work resulted in a significant decrease in serum cortisol, the stress hormone that could plausibly mediate the benefit of mind and body practices through reduced inflammation.
In addition, “people with diabetes live with what we call ‘diabetes distress’,” Watanabe explained.
“Management of blood glucose is very stressful. You have to watch what you eat, you have to measure your glucose, and for the average person, that gets stressful. And that stress just contributes to the difficulty of controlling blood glucose,” he noted.
The authors have reported no relevant financial relationships.
J Integr Complement Med. Published online September 7, 2022. Abstract