Interventions For High Blood Pressure

High blood pressure, or hypertension, is a global crisis; 1.39 billion people are estimated to have hypertension around the world, with low- and middle-income countries bearing the brunt of it due to the global disparities around hypertension awareness, control and treatment³. As a major risk factor for cardiovascular disease, particularly later in life, prevention and interventions for high blood pressure are a public health concern³.

High blood pressure causes the arteries in the body to stiffen and become less elastic, and this effect is exacerbated by age, leading to cardiovascular complications². However, studies have shown time and time again that high blood pressure is a clinically modifiable condition and that one of the best interventions is regular aerobic exercise². Two important measures of arterial elasticity are carotid artery compliance and carotid-femoral pulse wave velocity, and aerobic exercise has been shown to improve both measures in middle-aged and older people, likely due to decreased oxidative stress on the arterial wall². This shows that exercise is not only therapeutic in improving arterial stiffness in older people, but also a way to prevent complications of hypertension in younger people as they get older². Furthermore, while resistance and strength training alone don’t seem to have any protective effects on arterial stiffness, studies show that resistance training before aerobic exercise can augment the positive effects of aerobic exercise².

The problem that many clinicians run into with an exercise prescription, however, is that many people are non-compliant¹. This can be due to limitations on time, access, transportation and facility access, which results in less than 40% of adults following the recommended guidelines of 150 minutes a week of moderate exercise¹. Therefore, combatting high blood pressure and mediating its effects on long-term health requires interventions that everyone can try¹. A new form of physical training, known as Inspiratory Muscle Strength Training, has been shown to have promising effects on hypertensive patients¹. It requires patients to repeatedly inhale against resistance, thus building strength in inspiratory accessory muscles, and the most recent training program is only 30 breaths and can be performed with a handheld device that acts as a trainer¹. A 6-week long, double-blind, randomized control trial evaluated the efficacy of this particular IMST paradigm on the cardiovascular health of middle-aged and older patients with increased systolic blood pressure¹. Results showed that, overall, IMST reduced systolic blood pressure and diastolic pressure, and this reduction was roughly 75% sustained after completion of the program¹. This sustainability sets IMST apart from improvements after aerobic exercise and hypertensive therapies, in which blood pressure typically returns to pre-intervention levels once they are stopped¹. IMST also improved nitric oxide-mediated vasodilation, vascular endothelial function, and levels of CRP, which is a sensitive biomarker for inflammation¹. And most importantly, this study showed very high levels of adherence in this study population, potentially bridging the gap in efficacy that is seen with aerobic exercise recommendations¹.

IMST is still a relatively new intervention, but these early studies have shown that it is a promising therapeutic and preventative measure that also has a good compliance profile. More research is needed to strengthen these associations, however, IMST may become a clinically important recommendation to reduce the prevalence of hypertension and its cardiovascular complications.

References  

1. Craighead DH, Heinbockel TC, Freeberg KA, Rossman MJ, Jackman RA, Jankowski LR, Hamilton MN, Ziemba BP, Reisz JA, D’Alessandro A, Brewster LM, DeSouza CA, You Z, Chonchol M, Bailey EF, Seals DR. Time-Efficient Inspiratory Muscle Strength Training Lowers Blood Pressure and Improves Endothelial Function, NO Bioavailability, and Oxidative Stress in Midlife/Older Adults with Above-Normal Blood Pressure. Journal of the American Heart Association, 2021; 10(13): 501-506. https://doi.org/10.1177/0267659117696140

2. Craighead DH, Freeberg KA, Seals DR. The protective role of regular aerobic exercise on vascular function with aging. Exercise Physiology, 2019; 10: 55-53. https://doi.org/10.1016/j.cophys.2019.04.005

3. Wyss F, Coca A, Lopez-Jaramillo P, Ponte-Negretti C. Position statement of the InterAmerican Society of Cardiology on the current guidelines for prevention, diagnosis and treatment of arterial hypertension. International Journal of Cardiology Hypertension, 2020; 6. https://doi.org/10.106/j.ijchy.2020.100041