Effect Of Diaphragmatic Breathing On Heart Rate Variability In Ischemic Heart Disease With Diabetes - Kulur et al. (2009)
Consistent practice of diaphragmatic breathing reduced HbA1c by up to 2%
Heart rate variability was significantly increased after practice of diaphragmatic breathing
The Breathing Diabetic Summary
This is definitely one of the most important papers related to breathing and diabetes, showing a significant reduction in A1c from the practice of diaphragmatic breathing.
The authors were not planning to investigate glycemic control; it came as a “by-product” of their research on heart rate variability (HRV). HRV is also extremely important to diabetics. HRV is seen as metric reflective of overall health. It measures the natural rise and fall of the heart rate in response to different bodily functions, such as breathing or blood pressure fluctuations. Diabetics generally have a lower HRV than non-diabetics. Slow breathing (6 breaths per minute) has been shown to increase HRV, so the authors wanted to see if this exercise could also help diabetics both with and without autonomic abnormalities.
This study used patients with heart disease without diabetes, patients with heart disease and type 2 diabetes, but no autonomic neuropathy, and patients with heart disease, type 2 diabetes, and autonomic neuropathy. They also had 60 age-matched healthy subjects serving as the control group.
The patients were taught to breathe slowly using their diaphragm at a rate of 6 breaths per minute (Principle 1). They were asked to perform this for 10-15 minutes, twice daily, for 1 year. The authors followed up with the patients at the 3 and 12 month marks of the study period.
All of the groups showed a significant increase in HRV after following the breathing protocol, indicating an improvement in general health and wellbeing. Astonishingly, the participants also significantly lowered their HbA1c and blood glucose levels: The control group reduced their HbA1c by ~1.4% and the diabetics reduced their HbA1c by ~2.0%! That’s incredible! Imagine reducing your HbA1c from 8% to 6% by simply breathing slowly for 20-30 minutes a day. Perhaps not surprisingly, participants who did not comply with the breathing protocol saw a worsening of their HbA1c over time.
Getting back to the increased HRV, they used a statistical (regression) analysis to conclude that diaphragmatic breathing accounted for as much as 72% of the observed increases in HRV, making it a greater contributor than other factors such as medication.
The authors concluded that deep breathing increased HRV by decreasing sympathetic activity and, more generally, decreasing excitatory pathways related to the cardiovascular and respiratory systems. These same mechanisms were likely involved in the long-term lowering of the patients’ blood sugars and, subsequently, HbA1c.
Overall, this paper provides scientific evidence that slow, deep breathing can improve long-term blood sugars. Obviously, this is only one study, but a 2% reduction in HbA1c is remarkable. This study also supports the huge improvements I have seen in my own blood sugars. It also begs the question: Are you practicing Principle 1 yet?
Abstract from Paper
Background: Reduced heart rate variability is associated with an unfavorable prognosis in patients with ischemic heart disease and diabetes. Whether change in breathing pattern can modify the risk factor in these patients has not been definitely proved.
Objective: To evaluate the effect of diaphragmatic breathing on heart rate variability (HRV) in ischemic heart disease patients with diabetes.
Methods: Study population consisted of 145 randomly selected male patients of which 45 had ischemic heart disease (IHD), 52 had IHD and diabetes (IHD-DM) and the remaining 48 had IHD and diabetic neuropathy (IHD-DN). HRV was assessed by 5 minute-electrocardiogram using the time domain method. The intervention group was divided into compliant and non-compliant groups and follow-up recording was carried out after three months and one year.
Results: Baseline recordings showed a significant decrease in HRV in ischemic heart disease (IHD) patients with or without diabetes (p<0.01). IHD patients had higher HRV than IHD patients with diabetes (p<0.01) or diabetic neuropathy (p<0.01). Increase in HRV was observed in patients who practiced diaphragmatic breathing for three months (IHD-DM: p<0.01; IHD-DN: p<0.05) and for one year (IHD-DM: p<0.01; IHD-DN: p<0.01). The HRV significantly decreased after one year in non-compliant patients. The regular practice of diaphragmatic breathing also improved the glycemic index in these patients.
Conclusion: The regular practice of diaphragmatic breathing significantly improves heart rate variability with a favorable prognostic picture in ischemic heart disease patients who have diabetes. These effects seem to be potentially beneficial in the management of IHD patients with diabetes. (Arq Bras Cardiol 2009; 92(6) : 423-429)
Anupama Bangra Kulur, Nagaraja Haleagrahara, Prabha Adhikary, and Jeganathan P. S, (2009) Effect of Diaphragmatic Breathing on Heart Rate Variability in Ischemic Heart Disease with Diabetes, Arquivos Brasileiros de Cardiologia, 92(6), 423-429.