Blood pressure response during treadmill exercise testing and the risk for future cardiovascular events and new-onset hypertension

Patterns of systolic blood pressure response at the end of exercise and mortality and morbidity in patients referred for exercise testing

OBJECTIVES

Peak exercise systolic blood pressure (SBP) is associated with future cardiovascular disease (CVD) and mortality. We aimed to evaluate the predictive value of different SBP patterns at the end of exercise with these outcomes.

METHODS

We studied 6329 adults (45% women) referred for exercise testing, with test duration of 6-14 min, maximal effort and valid SBP measurements at the end of exercise. The two last SBPs were indexed to work rate (mmHg/Watt), defining responses as: drop (negative change), plateau (no change), slow (lower tertile of increase), intermediate (middle tertile) and steep (upper tertile). Data were cross-linked with nationwide disease and mortality registries. Associations with all-cause mortality and incident CVD were analysed using Cox proportional hazards regression (hazard ratio (HR), 95% confidence interval), using slow SBP increase as reference, adjusted for sex, age, body mass index, baseline CVD (mortality analysis only), beta-blockers and exercise capacity (peak Watt).

RESULTS

The prevalence of SBP responses at the end of exercise were drop (1.1%), plateau (15.0%), slow (30.4%), intermediate (25.2%) and steep increase (28.3%). Follow-up was 8.8±3.4 years. Compared with a slow increase, the adjusted all-cause mortality risks were not statistically different for a drop (HR 1.16 (0.50-2.65)), plateau (HR 1.19 (0.85-1.66)), intermediate (HR 1.24 (0.93-1.66)) or steep SBP increase (HR 1.16 (0.89-1.52)). CVD risk was increased in those with a SBP drop (HR 3.10 (1.85-5.19), but not significantly for plateau (HR 1.17 (0.92-1.48)), intermediate or steep SBP increases (HRs 0.99-1.00).

CONCLUSION

Subjects with a slow SBP increase at the end of exercise tended to have the lowest mortality risk, although no SBP response pattern predicted all-cause mortality independently. CVD risk was strongly increased in patients with a drop in SBP and tended to be increased (non-significantly) also in patients with a plateau in SBP at the end of exercise, in comparison with increasing SBP.

The Role of Exercise Blood Pressure in Hypertension: Measurement, Mechanisms, and Management

ABSTRACT

Hypertension affects one in three adults globally and is the leading modifiable risk factor for cardiovascular disease. Although blood pressure measurements at rest are fundamental to the detection and management of hypertension, abnormal blood pressure responses to exercise, namely, an exaggerated exercise blood pressure (EEBP), can provide additional independent information about current and future hypertension risk. This paper summarizes a symposium entitled, "The Role of Exercise Blood Pressure in Hypertension: Measurement, Mechanisms and Management" included at the 2023 American College of Sports Medicine annual meeting, which presented a timely discussion about the clinical utility of EEBP. Here we will summarize the evidence presented by the speakers including considerations for blood pressure measurement during exercise, an overview of EEBP thresholds and discussion about the value of EEBP during submaximal exercise for the identification and management of hypertension, a summary of the potential physiological mechanisms underpinning an EEBP, and a review of exercise prescription guidelines based on new and emerging evidence as they relate to the American College of Sports Medicine's exercise recommendations for hypertension. We conclude by highlighting areas for future research with the overarching goal of improving the measurement and management of hypertension.

Blood pressure response to graded bicycle exercise in males and females across the age and fitness spectrum

AIMS

Blood pressure (BP) responses to exercise are frequently measured, with the concern that greater increases are a marker of disease. We sought to characterize the normal exercise BP response in healthy adults and its relationships with age, sex, and fitness.

METHODS AND RESULTS

Five hundred and eighty-nine participants [median age 46 (interquartile range 24-56) years, 81% male] underwent cardiopulmonary exercise testing with repeated, automated BP measures. An exaggerated maximal systolic BP (SBPmax) was defined from current guidelines as ≥210 mmHg in males and ≥190 mmHg in females. Individual linear regression analyses defined the relationship between BP and workload (W; SBP/W-slope and DBP/W-slope). Participants with or without an exaggerated SBPmax and above- or below-median SBP/W-slope were compared. An exaggerated SBPmax was found in 51% of males and 64% of females and was more prevalent in endurance-trained athletes (males 58%, females 72%, P < 0.001). The mean SBP/W-slope was lower in males (0.24 ± 0.10 mmHg/W) than females (0.27 ± 0.12 mmHg/W, P = 0.031). In both sexes, peak oxygen uptake (VO2peak) was inversely correlated with SBP/W-slope (P < 0.01). Those with an exaggerated SBPmax and below-median SBP/W-slope were 10 years younger and had a 20% higher VO2peak, on average (P < 0.001). A non-exaggerated SBPmax and above-median SBP/W-slope was observed in older individuals with the lowest VO2peak.

CONCLUSION

In a large cohort of healthy individuals, an exaggerated SBPmax was common and associated with higher fitness. In contrast, higher SBP indexed to W was associated with older age, lower fitness, and female sex. Thus, sex, age, and fitness should be considered when evaluating BP response to exercise.

REGISTRATION

Pro@Heart: NCT05164328, ACTRN12618000716268; ProAFHeart: ACTRN12618000711213; Master@Heart: NCT03711539.

Risk Factors Associated With Exaggerated Blood Pressure Response at the Time of Exercise Treadmill Stress Test

BACKGROUND

Exaggerated blood pressure response (EBPR) to exercise stress testing (EST) may be a marker of future hypertension and carry valuable information for the prediction of cardiovascular events. We sought to evaluate the clinical and resting EST parameters associated with an increased likelihood of EBPR.

METHODS

The records of 14,073 patients (mean age: 55 ± 11 years) without known cardiovascular disease who underwent a treadmill EST were analyzed.

RESULTS

The overall prevalence of arterial hypertension was 44%. A considerable proportion (24%) of patients exhibited EBPR. Multivariate analysis of the entire study population showed that middle-aged individuals (40-60 years old), resting systolic BP > 130 mmHg and/or diastolic BP > 80 mmHg, known arterial hypertension, current cigarette smoking, and family history of premature coronary artery disease are all independent risk factors for EBPR (all P < 0.001). Although the presence of arterial hypertension increased the likelihood of EBPR in the analysis of the entire population, the relevant association in subjects above 60 years old is statistically nonsignificant (P = 0.120). Notably, the pre-test systolic BP > 130 mmHg and/or diastolic BP > 80 mmHg level increased significantly the likelihood of manifesting EBPR in all age categories (<40, 40-60, and >60 years old) independent of hypertension presence and in all hypertensive patients independently of antihypertensive treatment intake (all P < 0.001).

CONCLUSIONS

Considering the diagnostic and prognostic utility of EBPR during treadmill EST the clinical and resting hemodynamic parameters that increase the likelihood of EBPR are targets for interventions and preventive measures to modify lifestyle risk behaviors and reduce hypertension and cardiovascular risk factors in the early stages.

Exaggerated Blood Pressure Response to Exercise Is a Risk of Future Hypertension Even in Healthy, Normotensive Young Individuals-Potential Preventive Strategies for This Phenomenon?

Physical activity and regular exercise are well known to reduce the risks of cerebrovascular and cardiovascular diseases, leading the American College of Sports Medicine to endorse the concept that "exercise is medicine". However, a single bout of exercise temporarily raises arterial blood pressure (BP) to meet the metabolic demands of working muscle, and this BP response is particularly exaggerated in older adults and patients with cardiovascular conditions, such as hypertension, resulting in an exaggerated BP response during exercise. This presents a paradox: while regular exercise is crucial for preventing these diseases, excessively high BP responses during exercise could increase the risk of vascular damage. The mechanisms underlying this exaggerated BP response during exercise remain unclear, and effective exercise regimens for these populations have yet to be established. Currently, low-intensity exercise is recommended; however, its efficacy in disease prevention is uncertain. Notably, even among healthy individuals, there is significant variation in the BP response to exercise. Some healthy individuals, despite having normal resting BP, exhibit an exaggerated BP response during physical activity. Importantly, these individuals are often unaware that their BP becomes excessively elevated during physical activity. Repeated exposure to these heightened BP responses through regular physical activity may increase their long-term risk of cardiovascular disease. How can we prevent disease development in these individuals while still ensuring the effectiveness of exercise? Some studies have shown that individuals with a family history of hypertension may experience this phenomenon even in children and adolescents. Additionally, left ventricular hypertrophy contributes to an exaggerated BP response to exercise, suggesting a possible genetic influence. Conversely, other reports indicate that factors such as arterial stiffness, obesity, and low exercise capacity also contribute to this exaggerated response. Our recent preliminary data suggest that the cognitive benefits of exercise may be diminished in individuals who exhibit an exaggerated BP response during exercise. This implies that individuals with an exaggerated BP response, despite having normal resting BP, may not fully benefit from exercise. In this perspective paper, we review the physiological aspects of this phenomenon and explore strategies to address it. Additionally, we discuss BP responses in athletes within this content. Our goal is to prevent disease while maximizing the benefits of exercise for healthy individuals with an exaggerated BP response, as well as for elderly and cardiovascular patients.

Exercise systolic blood pressures are unaffected by time of day in healthy young adults

Blood pressure (BP) assessment during exercise testing has the capacity to identify exaggerated exercise BP (EEBP). BP has a circadian rhythm; therefore, exercise BPs may change throughout the day complicating EEBP identification. The purpose of this study was to determine the effect of time of day on exercise BP in healthy young adults. Thirty-one participants [48% female; 23(4) years] completed a modified Bruce treadmill protocol in the morning (M), afternoon (A), and evening (E). Submaximal (stage 4) and peak (highest value) systolic BP (SBP) were determined and ΔSBP was calculated (peak SBP-pre-exercise SBP). Repeated-measures tests were used to compare SBP data. EEBP was defined as a submaximal SBP ≥ 170 mmHg. Chronotype was assessed using the Morning-Eveningness Questionnaire (MEQ) and Pearson correlations were used to determine the relationship between MEQ score and ΔSBP during all tests. Significance was set at P < 0.05. Submaximal SBP (M:159(25); A:156(16); E:162(24) mmHg; P = 0.295), peak SBP (M:177(32); A:184(25); E:185(26) mmHg; P = 0.087) and ΔSBP (M:62(29); A:67(23); 65(20) mmHg; P = 0.546) were similar across time points. Eight participants had an EEBP on at least two tests. MEQ scores were correlated with ΔSBP during the A test (r = 0.357, P = 0.049) and E test (r = 0.363, P = 0.045). In conclusion, time of day had no effect on SBP responses to exercise, but our correlational analysis suggests changes in SBP may differ between chronotypes depending on the time of day of exercise. Given the clinical value of EEBP, it is notable that 26% of our healthy young sample had EEBP.

CAVI (Cardio-Ankle Vascular Index) as an independent predictor of hypertensive response to exercise

OBJECTIVES

Hypertensive response to exercise (HRE) is related to the development of future hypertension, cardiovascular morbidity, and mortality, independent of resting blood pressure. We hypothesized that arterial stiffness as measured by cardio-ankle vascular index (CAVI) could be an independent predictor of HRE.

MATERIALS AND METHODS

Retrospective chart review of patients participated in the preventive health program at the Bangkok Heart Hospital who underwent both CAVI and treadmill stress testing on the same day between June and December 2018 were performed. Variables for the prediction of HRE were analyzed using univariate analysis, and significant variables were entered into multiple logistic regression. An ROC curve was created to test the sensitivity and specificity of CAVI as a predictor of HRE.

RESULTS

A total of 285 participants (55.1% female) were enrolled in this study. There were 58 patients (20.4%) who met the HRE definition (SBP > 210 mmHg in males, SBP > 190 mmHg in females, or DBP > 110 mmHg in both males and females), with a mean age of 46.4 12.8 years. In univariate analysis, age, systolic blood pressure at rest, diastolic blood pressure at rest, pulse pressure at rest, diabetes mellitus, hypertension, dyslipidemia, history of beta-blocker, and CAVI results were statistically significant. Multiple logistic regression revealed that CAVI and systolic blood pressure were statistically significant predictors of HRE with OR of 5.8, 95%CI: 2.9-11.7, P < 0.001 and OR 1.07, 95%CI: 1.03-1.10, P = 0.001 respectively. ROC curve analysis of the CAVI revealed an AUC of 0.827 (95%CI: 0.76-0.89, p < 0.001), and the sensitivity and specificity of cut-point CAVI > 8 were 53% and 92%, respectively.

CONCLUSION

This study demonstrated that CAVI is an independent predictor of hypertensive response to exercise. Additionally, the findings suggest that CAVI > 8 can be a valuable tool in identifying individuals at risk for hypertensive responses during exercise.

Targeting Hypertensive Response to Exercise and the Association of Masked Hypertension With Subclinical Organ Damage: A Mini-Review and Meta-Analysis

BACKGROUND

Emerging evidence suggests that a hypertensive response to exercise (HRE) during dynamic or isometric stress tests assessing cardiac function is predictive of hypertension and cardiovascular events such coronary artery disease, heart failure and stroke. Whether HRE represents a marker of masked hypertension (MH) in individuals with no prior history of hypertension is still unclear. This is also the case for the association between MH and hypertension-mediated organ damage (HMOD) in the HRE setting.

METHODS

We addressed this issue through a review and a meta-analysis of studies providing data on this topic in normotensive individuals undergone both to dynamic or static exercise and to 24-h blood pressure monitoring (ABPM). A systematic search was performed using Pub-Med, OVID, EMBASE and Cochrane library databases from inception up to February 28th 2023.

RESULTS

Six studies including a total of 1,155 untreated clinically normotensive individuals were considered for the review. Data provided by the selected studies can be summarized as follows: (i) HRE is a BP phenotype linked to a high prevalence of MH (27.3% in the pooled population); (ii) MH is, in turn, associated with a greater, consistent likelihood of echocardiographic left ventricular hypertrophy (OR: 4.93, CI: 2.16-12.2, P < 0.0001) and vascular organ damage, as assessed by pulse wave velocity, (SMD: 0.34 ± 0.11, CI: 0.12-0.56, P = 0002).

CONCLUSIONS

On the basis of this, albeit limited, evidence, the diagnostic work-up in individuals with HRE should primarily be addressed to look for MH as well as for markers of HMOD, a highly prevalent alteration in MH.

Non-pharmacological interventions for older adults with postprandial hypotension: A scoping review

BACKGROUND

Older adults frequently suffer from postprandial hypotension, associated with an increased risk of falls, syncope, acute cardiovascular and cerebrovascular diseases, and even death. Researchers use non-pharmacological interventions, but related literature is dispersed and lacks a latest summary.

OBJECTIVE

The aim of this study was to map and examine non-pharmacological interventions currently employed to assist older adults with postprandial hypotension and lay a solid foundation for future studies.

METHODS

This study adhered to the JBI methodology for scoping reviews and preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews. PubMed, Web of Science, Embase, Cochrane Library, CINAHL, SCOPUS, Chinese Biomedical Journal, China National Knowledge Infrastructure, VIP and WAN FANG Data were retrieved from their inception to 1 August 2022.

RESULTS

Two randomized controlled trials and seven quasi-experimental studies were included. Small meals, exercise interventions, fibre with meals, green tea and water therapy have been reported to prevent postprandial hypotension effectively; however, position changes have been reported to have no impact on postprandial blood pressure decrease. Additionally, the blood pressure determination methods and test meals may affect observed trial effects.

CONCLUSION

Large samples and long-term follow-up studies are needed to prove the efficacy and safety of existing non-pharmacological interventions. Future studies should develop a BP determination method based on the postprandial BP decline trajectory induced by a given test meal to improve the reliability of study results.

RELEVANCE TO CLINICAL PRACTICE

This review broadly summarizes existing studies on developing and validating non-pharmacological interventions for older adults with postprandial hypotension. It also analyses special factors that may influence the trial effects. This may provide a useful reference for future research.

Type-2 Diabetes and the Clinical Importance of Exaggerated Exercise Blood Pressure

BACKGROUND

Exaggerated exercise blood pressure (EEBP) during clinical exercise testing is associated with poor blood pressure (BP) control and cardiovascular disease (CVD). Type-2 diabetes (T2DM) is thought to be associated with increased prevalence of EEBP, but this has never been definitively determined and was the aim of this study.

METHODS

Clinical exercise test records were analyzed from 13 268 people (aged 53±13 years, 59% male) who completed the Bruce treadmill protocol (stages 1-4, and peak) at 4 Australian public hospitals. Records (including BP) were linked to administrative health datasets (hospital and emergency admissions) to define clinical characteristics and classify T2DM (n=1199) versus no T2DM (n=12 069). EEBP was defined as systolic BP ≥90th percentile at each test stage. Exercise BP was regressed on T2DM history and adjusted for CVD and risk factors.

RESULTS

Prevalence of EEBP (age, sex, preexercise BP, hypertension history, CVD history and aerobic capacity adjusted) was 12% to 51% greater in T2DM versus no T2DM (prevalence ratio [95% CI], stage 1, 1.12 [1.02-1.24]; stage 2, 1.51 [1.41-1.61]; stage 3, 1.25 [1.10-1.42]; peak, 1.18 [1.09-1.29]). At stages 1 to 3, 8.6% to 15.8% (4.8%-9.7% T2DM versus 3.5% to 6.1% no-T2DM) of people with 'normal' preexercise BP (<140/90 mm Hg) were identified with EEBP. Exercise systolic BP relative to aerobic capacity (stages 1-4 and peak) was higher in T2DM with adjustment for all CVD risk factors.

CONCLUSIONS

People with T2DM have higher prevalence of EEBP and exercise systolic BP independent of CVD and many of its known risk factors. Clinicians supervising exercise testing should be alerted to increased likelihood of EEBP and thus poor BP control warranting follow-up care in people with T2DM.

Systolic Blood Pressure Response to Exercise in Endurance Athletes in Relation to Oxygen Uptake, Work Rate and Normative Values

Work rate has a direct impact on the systolic blood pressure (SBP) during aerobic exercise, which may be challenging in the evaluation of the SBP response in athletes reaching high work rates. We aimed to investigate the exercise SBP response in endurance athletes in relation to oxygen uptake (VO2), work rate and to recent reference equations for exercise SBP in the general population. Endurance athletes with a left-ventricular end-diastolic diameter above the reference one performed a maximal bicycle cardiopulmonary exercise test. The increase in SBP during exercise was divided by the increase in VO2 (SBP/VO2 slope) and in Watts, respectively (SBP/W slope). The maximum SBP (SBPmax) and the SBP/W slope were compared to the predicted values. In total, 27 athletes (59% men) were included; mean age, 40 ± 10 years; mean VO2max, 50 ± 5 mL/kg/min. The mean SBP/VO2 slope was 29.8 ± 10.2 mm Hg/L/min, and the mean SBP/W slope was 0.27 ± 0.08 mm Hg/W. Compared to the predicted normative values, athletes had, on average, a 12.2 ± 17.6 mm Hg higher SBPmax and a 0.12 ± 0.08 mm Hg/W less steep SBP/W slope (p < 0.01 and p < 0.001, respectively). In conclusion, the higher SBPmax values and the less steep SBP/W slope highlight the importance of considering work rate when interpreting the SBP response in endurance athletes and suggest a need for specific normative values in athletes to help clinicians distinguish physiologically high maximal blood pressure from a pathological blood pressure response.

Blood pressure measurements during treadmill exercise testing and the risk for the future development of atrial fibrillation

Hypertension is a well-established risk factor for the onset and progression of atrial fibrillation (AF). Blood pressure (BP) measurements during routine exercise stress testing (EST) may identify subjects at increased risk for developing AF. We performed a retrospective analysis of treadmill EST carried out using the Bruce protocol in patients aged ≥40 years without a history of AF (n = 17,617; 42% women). BP was measured at rest, peak exercise, and 2-min recovery and analyzed for its association with the risk for developing AF. During a mean follow-up of 7 years, AF was documented in 4.5% of the patients. The incidence rate of AF per 1000 person-years increased with the rise in CHA₂DS₂VASc scores (3.26 for a Score=0 to 19.78 for scores ≥6). In a multivariate analysis, adjusting for risk score components and exercise capacity, systolic BP measurements taken at rest (≥130 vs. ≤110 mmHg), peak exercise (>170 vs. ≤150 mmHg), and recovery (>150 vs. ≤130 mmHg) were associated with an increased risk for AF: the hazard ratios (HRs) were 1.56 (95% CI, 1.30-1.87), 1.21 (1.01-1.45), and 1.33 (1.10-1.62), respectively. Similarly, diastolic BP measurements taken at rest (≥90 vs. <80 mmHg), peak exercise (≥100 vs. <90 mmHg), and recovery (>90 vs. ≤80 mmHg) were associated with an increased risk for AF: the HRs were 1.80 (1.36-2.38), 2.08 (1.28-3.37), and 1.56 (0.81-3.02), respectively. The association of exercise BP with AF was further observed when the BPs were analyzed as continuous variables and in subjects without a baseline diagnosis of hypertension. In conclusion, systolic and diastolic BP taken at the rest, peak exercise and recovery phases of EST may provide independent predictive information regarding future risk for developing AF.

The Identification and Management of High Blood Pressure Using Exercise Blood Pressure: Current Evidence and Practical Guidance

High blood pressure (BP) is a leading risk factor for cardiovascular disease (CVD). The identification of high BP is conventionally based on in-clinic (resting) BP measures, performed within primary health care settings. However, many cases of high BP go unrecognised or remain inadequately controlled. Thus, there is a need for complementary settings and methods for BP assessment to identify and control high BP more effectively. Exaggerated exercise BP is associated with increased CVD risk and may be a medium to improve identification and control of high BP because it is suggestive of high BP gone undetected on the basis of standard in-clinic BP measures at rest. This paper provides the evidence to support a pathway to aid identification and control of high BP in clinical exercise settings via the measurement of exercise BP. It is recommended that exercise professionals conducting exercise testing should measure BP at a fixed submaximal exercise workload at moderate intensity (e.g., ~70% age-predicted heart rate maximum, stage 1-2 of a standard Bruce treadmill protocol). If exercise systolic BP is raised (≥170 mmHg), uncontrolled high BP should be assumed and should trigger correspondence with a primary care physician to encourage follow-up care to ascertain true BP control (i.e., home, or ambulatory BP) alongside a hypertension-guided exercise and lifestyle intervention to lower CVD risk related to high BP.