The effect of slow-loaded breathing training on the blood pressure response to handgrip exercise in patients with isolated systolic hypertension.

Isolated systolic hypertension (ISH) is the most common form of hypertension in older people. It is characterized by increased resting systolic blood pressure (sBP) and increased sBP in response to exercise. It has previously been shown that slow breathing training reduces resting sBP, and the objective of the present study was to determine whether it also reduced the blood pressure response to static handgrip exercise. ISH patients aged between 60 and 74 years were randomly divided into a control group (10 subjects, 4 of which were male) that breathed normally and a trained group (10 subjects, 4 of which were male) that trained daily for 8 weeks by slow breathing against an inspiratory resistance of 18 cmH2O. Before and immediately after training, subjects underwent a 2-min handgrip test (30% max) followed by 2 min of post-exercise circulatory occlusion (PECO) to assess metaboreflex activity. Training reduced sBP by 10.6 mm Hg (95% confidence interval (CI), -16 to -5 mm Hg, P=0.004), but changes were not observed in the control group. The peak exercise sBP was reduced by 23 mm Hg (95% CI, -16 to -31 mm Hg, P<0.001), while the increase in the sBP above resting was reduced by 12.6 mm Hg (95% CI, -6.9 to -18.2 mm Hg, P=0.002). The sBP during PECO was reduced by 8.9 mm Hg (95% CI, -4 to -14 mm Hg, P=0.008), which is indicative of reduced metaboreflex activity; no such change was observed in the control group. The results demonstrate that conventional treatment of older patients with ISH may be improved in two ways by slow breathing training: resting sBP may be reduced by 10 mm Hg, more than can be achieved by conventional pharmacological therapies, while the response to static exercise may be reduced by approximately twice this value.

Breathing Training for Older Patients with Controlled Isolated Systolic Hypertension.

INTRODUCTION: Isolated systolic hypertension (ISH) is very common but difficult to manage with conventional medication. We investigated whether slow breathing training, with and without an inspiratory load, could reduce the resting blood pressure of older well-managed ISH patients. METHODS: Thirty ISH patients (66 ± 4 yr) were randomized into loaded breathing (six breaths per min, 18 cm H2O), unloaded breathing (six breaths per min, no load), or control (normal breathing) groups. After a 2-wk run-in, loaded and unloaded groups trained at home for 30 min every day for 8 wk. Morning home blood pressure and heart rate were measured daily throughout the study. At the end of training, all participants reverted to normal breathing, and blood pressure and heart rate were recorded for a further 8 wk. RESULTS: Compared to the pretraining run-in period, systolic blood pressure was reduced by 18 ± 7 and 11 ± 4 mm Hg for loaded and unloaded groups, respectively (P < 0.001), the reduction being significantly larger for the loaded group (P < 0.05) after 8-wk training. There were no changes in the control group. After the end of training, systolic blood pressure remained below pretraining levels for a further 6 wk for the loaded group but for only 2 wk with the unloaded group. There was a small nonsignificant reduction in diastolic blood pressure with training, as there was for heart rate. Pulse pressures were reduced by 11 ± 5 and 5 ± 6 mm Hg for loaded and unloaded groups, respectively (P < 0.01). CONCLUSION: Slow breathing training, especially with an inspiratory load, is very effective in reducing resting systolic and pulse pressures and could be a valuable adjunct in the management of ISH.

Older Women with Controlled Isolated Systolic Hypertension: Exercise and Blood Pressure.

INTRODUCTION: Exercise is generally regarded as beneficial for health, but the consequent increases in blood pressure might pose a risk for hypertensive subjects. The purpose of this study was to determine blood pressure responses to dynamic exercise and sustained handgrip in patients with isolated systolic hypertension (ISH) who were stable on medication. METHODS: Nineteen female ISH patients (66 ± 5 yr) and 19 age-matched normotensive (NT) female controls undertook a 5-min cycle exercise (60% heart rate reserve [HRR]) and a 2-min handgrip exercise (30% maximum voluntary contraction). Blood pressure responses were measured using an oscillometric cuff, together with heart rate and resting brachial pulse transit times. RESULTS: Systolic blood pressure (SBP) levels after cycle exercise were 194 ± 18 and 153 ± 19 mm Hg for ISH and NT, respectively, with the increase above resting being greater for ISH (P < 0.001), and only small changes were found in diastolic blood pressure (DBP). During handgrip exercise, SBP rose to 168 ± 19 and 140 ± 8 mm Hg for ISH and NT, respectively. The increases above baseline were greater for ISH both during the exercise and postexercise circulatory occlusion (P = 0.017). The increase in DBP levels during exercise and postexercise occlusion were similar in ISH and NT, suggesting little difference in metaboreflex sensitivity. Pulse transit time was shorter for ISH compared with NT (166 ± 6 ms and 242 ± 24 ms, respectively, P < 0.001), indicating stiffer arteries, which would increase SBP but not DBP. CONCLUSION: Despite being well controlled and normotensive control subjects at rest, ISH patients had high SBP responses to both dynamic and static exercises, which may constitute a risk for cardiovascular incidents.

An inspiratory load enhances the antihypertensive effects of home-based training with slow deep breathing: a randomised trial.

QUESTION: Can adding an inspiratory load enhance the antihypertensive effects of slow breathing training performed at home? DESIGN: Randomised trial with concealed allocation. PARTICIPANTS: Thirty patients with essential hypertension Stage I or II. INTERVENTION: Experimental groups performed slow deep breathing at home, either unloaded or breathing against a load of 20 cmH(2)O using a threshold-loaded breathing device. Participants trained for 30 min, twice daily for 8 weeks. A control group continued with normal activities. OUTCOME MEASURES: Resting blood pressure and heart rate were measured at home and in the laboratory before and after the training period. RESULTS: Compared to the control group, systolic and diastolic blood pressure decreased significantly with unloaded breathing by means of 13.5 mmHg (95% CI 11.3 to 15.7) and 7.0 mmHg (95% CI 5.5 to 8.5), [corrected] respectively (laboratory measures). With loaded breathing, the reductions were greater at 18.8 mmHg (95% CI 16.1 to 21.5) and 8.6 mmHg (95% CI 6.8 to 10.4), respectively. The improvement in systolic blood pressure was 5.3 mmHg (95% CI 1.0 to 9.6) greater than with loaded compared to unloaded [corrected] breathing. Heart rate declined by 8 beats/min (95% CI 6.5 to 10.3) with unloaded breathing, and 9 beats/min (95% CI 5.6 to 12.2) with loaded breathing. Very similar measures of blood pressure and heart rate were obtained by the patients at home. CONCLUSION: Home-based training with a simple device is well tolerated by patients and produces clinically valuable reductions in blood pressure. Adding an inspiratory load of 20 cmH(2)O enhanced the decrease in systolic blood pressure. TRIAL REGISTRATION: NCT007919689.