Every step counts and more steps count more for cardiovascular event prevention in hypertension

This editorial refers to ‘Prospective associations of daily step count and stepping intensity with overall and type-specific major adverse cardiovascular events in people with hypertension’, by S.W.M. Cheng et al., https://doi.org/10.1093/eurjpc/zwaf441. Physical inactivity is a well-established risk factor for multiple chronic conditions, including coronary heart disease, stroke, heart failure, hypertension, type 2 diabetes mellitus, obesity, osteoporosis, depression, and some cancers.1 Globally, it accounts for an estimated 6% of the disease burden from coronary heart disease.1 The health benefits of physical activity are well documented, including a reduced risk of cardiovascular disease (CVD) and hypertension.2 Therefore, the World Health Organization (WHO) 2020 guidelines on physical activity and sedentary behaviour recommend that all adults engage in at least 150 min of moderate-to-vigorous activity per week, or at least 75 min of vigorous-intensity activity, along with muscle-strengthening exercises for all major muscle groups at least twice weekly.2 Despite this, many adults worldwide remain insufficiently active. The WHO recommendations, derived mainly from studies assessing exercise time through self-reported questionnaires,2 provide targets for time spent in moderate-to-vigorous exercise. However, alternative measures, like step counts, were not included due to limited evidence at the time.2 Steps are a basic unit of locomotion and, as such, provide a metric of ambulation—an important component of physical activity. Importantly, emerging evidence suggests that health benefits accrue well below the popularized 10 000-step goal3—a target long promoted without scientific foundation and originating from the Manpo-Kei (‘10 000-step metre’ in Japanese), the first commercial pedometer marketed around the 1964 Tokyo Olympics. For example, compared with 2000 steps/day, achieving 4000 steps/day is associated with a 36% lower all-cause mortality risk.3 Risk reductions continue with each additional 1000 steps up to at least 7000 steps/day.3 Notably, the current WHO exercise targets of obtaining at least 150 min of moderate-to-vigorous activity per week correspond roughly to about 7000 steps/day.4 In hypertension, different types of exercise interventions have been found to be as effective as most antihypertensive medications in lowering systolic blood pressure,5 and engaging in physical activity is associated with reduced CVD mortality risk.6 In addition to lowering blood pressure and in contrast to most antihypertensive medications, physical activity and exercise affect many cardiometabolic risk factors (measurable and unmeasurable) which often coexist in patients with hypertension. However, structured exercise has not been studied as extensively as antihypertensive medications.5 When considering the mode and intensity of aerobic exercise, high-intensity interval training produces blood pressure reductions comparable with those achieved through moderate continuous exercise.5 Furthermore, dynamic resistance training also results in blood pressure reductions that are similar to those observed with aerobic exercise.7,8 Consequently, current guidelines encourage all adults to incorporate physical activity and exercise, along with other healthy lifestyle components, for the prevention and management of hypertension.7,8 Regarding the recommended amount of exercise, the European7 and American8 hypertension guidelines largely align with the WHO 2020 guidelines on physical activity and sedentary behaviour.2 As in the general population, hypertension guidelines do not specify step count targets for patients with hypertension, as both minimum and optimal step counts remain uncertain.7,8 In this issue of the Journal, Cheng et al.9 analysed 36 192 UK Biobank participants with hypertension but without known CVD, who wore accelerometers (Axivity AX3, Axivity, York, UK) for at least three valid days (>16 h/day, including one weekend day). They report non-linear inverse associations between daily step count and peak 30 min cadence with risk of major adverse cardiovascular events (MACE), defined as CVD death or incidence of heart failure, myocardial infarction, or stroke.9 For each 1000-step/day increase, risk decreased by 17.1% for MACE, 22.4% for heart failure, 9.3% for myocardial infarction, and 24.5% for stroke.9 Notably, the magnitude of associations was comparable between participants with and without hypertension, except for myocardial infarction, where the magnitude of risk association was smaller in those without hypertension.9 Additionally, a higher peak 30 min cadence was associated with a lower risk, independent of step count, with benefits observed above 38.3 steps/minute without an upper threshold.9 An undisputed strength of the study is the large sample size, balanced sex distribution, and specific focus on individuals with hypertension, a group for whom evidence on the health benefits of daily step counts has been limited. It should be noted, however, that some limitations must be acknowledged. First, nearly one-quarter (24%) of participants with hypertension in the accelerometer sub-study were excluded, primarily for prevalent CVD (59% of excluded participants) or missing covariate data (35%). Second, step counts and cadence were measured only at baseline and may not be representative of long-term activity since physical activity and sedentary behaviour often change throughout life. Third, by excluding participants with prevalent CVD at baseline and MACE during the first year to reduce the risk for reverse causation,2 and as most participants were White race and had higher education levels, the generalizability of the findings might be limited. Although frequently used interchangeably, it is important to distinguish between step count, physical activity, and exercise. Most often, physical activity refers to any bodily movement produced by skeletal muscles that expends energy, whereas exercise is planned, structured physical activity undertaken to promote health and fitness benefits.2 Step counts provide an objective measure of physical activity and are increasingly used in both research and clinical practice as it can be easily measured with consumer-grade wearables and smartphones. They offer advantages over traditional self-reported questionnaires, which are subject to recall and social desirability biases, tend to overestimate moderate-to-vigorous physical activity, underestimate sedentary time, and fail to capture light physical activity. For example, in the present study, participants may have overstated healthy behaviours, such as reporting an average intake of eight servings of fruits and vegetables per day. Moreover, light activities occupy far more time than exercise for most individuals. Compared with self-reported physical activity, device-measured physical activity was a stronger indicator of disease risk.10 For patients who are reluctant to exercise—whether due to physical limitations or lack of readiness—step count targets may represent a less daunting and more attainable goal, since all steps contribute, not only those taken during structured exercise. However, step counts do not account for non-ambulatory activities, such as cycling and swimming, nor do they provide contextual information about the intensity, type (aerobic, muscle-strengthening, or bone strengthening activity), or domain (occupational, household, transportation, and leisure-time) of activity performed.2 This is particularly noteworthy because higher levels of leisure-time physical activity are associated with a reduced risk of MACE, while higher levels of occupational physical activity are linked to an increased risk.11 In the case of ‘weekend warriors’, who concentrate their physical activity into just 1 or 2 days and appear to have a similar risk of CVD outcomes compared with those who distribute their activity more evenly throughout the week,12 step count might overestimate CVD risk. Furthermore, optimal activity targets may vary among different populations, particularly based on factors like age. Cheng et al.9 deserve recognition for their study, which provides valuable evidence that device-measured step counts can predict CVD outcomes and serve as potential goals for physical activity in individuals with hypertension. Step counts are becoming increasingly attractive because they are straightforward, objective, and attainable. However, daily step goals should not replace traditional time-based exercise recommendations; rather, they should complement them. As more evidence emerges, clinicians should consider prescribing exercise time, step-count targets (including those at higher pace), or a combination of both, tailored to each patient’s preferences, comorbidities, and available resources. Ultimately, the guiding principle is clear: some activity is better than none, and more activity is better than some. None declared.