Effects of guided breathing on blood pressure and heart rate variability

Effects of guided breathing on blood pressure and heart rate variability in hypertensive diabetic patients - Howorka et al. (2013)

Key Points

Slow breathing reduces blood pressure in hypertensive diabetics
Slow breathing improves heart rate variability in these same patients
Practicing slow breathing for 12 minutes/day causes a reduction in natural breathing rate

The Breathing Diabetic Summary

Diabetics suffer from a higher prevalence of hypertension. (Side note: It seems like every paper I read shows how diabetes is related to some other bad disease/complication. Doing this research is sometimes frightening, but it is also empowering because it let’s me know the reality of my situation and also gives me insights in to how I can avoid or mitigate some of these problems.) Previous research has shown that slow breathing can reduce blood pressure and improve heart rate variability (which is a key marker of overall autonomic function). This paper set out to see if slow breathing could improve both of these parameters in diabetics that suffer from hypertension.

Their study included 32 diabetic patients with hypertension. The subjects were evenly divided into two groups: a control group that continued their standard care and an intervention group that continued their standard care and also added in a slow breathing protocol. The intervention group used a device called RESPeRATE® that gradually guided their breathing toward slower rates. The goal was to get their breathing below 10 breaths per minute. Patients were instructed to complete one 12-minute session every day for 8 weeks.

Importantly, I want to reiterate that the breathing protocol was considered an add-on to normal care. It was not that patients stopped taking medicine or made any other changes to their lives, they simply added 12 minutes of slow breathing into their daily routine.

The results showed that slow breathing significantly reduced overall systolic blood pressure and pulse pressure. The control group had no significant changes in these parameters. Notably, the RESPeRATE® device showed that the patients typically achieved an exhale length that was 50% longer than their inhale length. The authors suspect that the longer exhale led to the significantly increased heart rate variability that was also seen in the intervention group.

Another interesting result was that the patients’ spontaneous breathing rate was slower from the daily 12-minute practice. That is, by practicing slow breathing everyday, it caused the patients to begin breathing slower naturally. In my opinion, this is where the magic happens: All of the benefits we have seen from “sessions” of slow breathing can now be achieved 24/7. (See how spontaneous breathing impacts the nervous system here.)

In conclusion, this paper showed that practicing slow breathing for 12 minutes/day for 8 weeks reduced blood pressure, increased heart rate variability, and reduced spontaneous breathing rate. A quote from the paper says it better than I ever could:

“If consistently used, guided breathing enhances restoration of physiological autonomic balance in patients with diabetes and hypertension.”

Abstract from Paper

Objective: Our aim was to investigate medium-term effects of device-guided breathing on blood pressure (BP) and its capacity to improve the cardiovascular autonomic balance in hypertensive diabetic patients. This feasibility study was conceived as a proof-of concept trial under real life conditions for justification of further investigations.

Methods: A randomized, controlled study (RCT) of the effects of device-guided slow breathing on top of usual care against usual care alone (including non-pharmacological and pharmacological treatment). The intervention included 12-min sessions of guided breathing performed daily for 8 weeks. Treatment effects were assessed with ambulatory blood pressure monitoring (24 h ABPM) andwith spectral analysis of short-termheart rate variability (HRV) obtained during standardized modified orthostatic load. Thirty-two subjects with diabetes and antihypertensive therapy were randomly assigned to both study groups.

Results: After 8 weeks of guided breathing, significant reductions were demonstrated in 24 h systolic BP (x ± SEM: 126.1 ± 3.0 vs 123.2 ± 2.7 mm Hg, p = 0.01), and in 24 h pulse pressure (PP, 53.6 ± 2.6 vs. 51.3 ± 2.5 mm Hg, p = 0.01), whereas no significant impact in the control group was shown. The differences in treatment effects (delta mm Hg, RESPeRATE® vs control) were significant only for PP (−2.3 ± 0.8 vs +0.2 ± 1.2 mm Hg, p < 0.05). Strong baseline dependence of treatment effects (delta systolic BP) was observed (p < 0.01). Guided breathing showed a stronger treatment effect in terms of an increase in HRV, predominantly in low frequency band (p < 0.03 vs. usual care).

Conclusion: Even in well controlled hypertensive diabetic patients, guided breathing induced relevant effects on BP and HRV, finding which should be investigated further.

Journal Reference:

Kinga Howorka, Jiri Pumprla, Jennifer Tamm, Alfred Schabmann, Sophie Klomfar, Elysee Kostineak, NoraHoworka, and Eliska Sovova, (2013) Effects of guided breathing on blood pressure and heart rate variability in hypertensive diabetic patients, Autonomic Neuroscience: Basic and Clinical, 179, 131–137, http://dx.doi.org/10.1016/j.autneu.2013.08.065.