Exercise systolic blood pressure at moderate workload predicts cardiovascular disease and mortality through 35 years of follow-up in healthy, middle-aged men

Exercise Systolic Blood Pressure Response During Cycle Ergometry is Associated with Future Hypertension in Normotensive Individuals

AIMS

We aimed to investigate the association between the exercise systolic blood pressure (SBP) response and future hypertension (HTN) in normotensive individuals referred for cycle ergometry, with special regard to reference exercise SBP values, and exercise capacity.

METHODS

In this longitudinal cohort study, data from 14,428 exercise tests were cross-linked with Swedish national registries on diagnoses and medications. We excluded individuals with a baseline diagnosis of cardiovascular disease or HTN. The peak exercise SBP (SBPpeak) was recorded and compared to the upper limit of normal (ULN) derived from SBPpeak reference equations incorporating age, sex, resting SBP and exercise capacity. To evaluate the impact of exercise capacity, three SBP to work rate slopes (SBP/W-slopes), were calculated, relative to either supine or seated SBP at rest or to the first exercise SBP. Adjusted hazard ratios (HRadjusted [95% Confidence interval, CI]) for incident HTN during follow-up, in relation to SBP response metrics, were calculated.

RESULTS

We included 3,895 normotensive individuals (49±14 years, 45% females) with maximal cycle ergometer tests. During follow-up (median 7.5 years) 22% developed HTN. Higher SBPpeak and SBPpeak>ULN were associated with incident HTN (HRadjusted 1.19 [1.14-1.23] per 10 mmHg, and 1.95 [1.54-2.47], respectively). All three SBP/W-slopes were positively associated to incident HTN, particularly the SBP/W-slope calculated as supine-to-peak SBP (HRadjusted 1.25 [1.19-1.31] per 1 mmHg/10W).

CONCLUSION

Both SBPpeak>ULN based on reference values and high SBP/W-slopes were associated with incident HTN in normotensive individuals and should be considered in the evaluation of the cycle ergometry SBP response.

Neurocirculatory regulation and adaptations to exercise in chronic kidney disease

Chronic kidney disease (CKD) is characterized by pronounced exercise intolerance and exaggerated blood pressure reactivity during exercise. Classic mechanisms of exercise intolerance in CKD have been extensively described previously and include uremic myopathy, chronic inflammation, malnutrition, and anemia. We contend that these classic mechanisms only partially explain the exercise intolerance experienced in CKD and that alterations in cardiovascular and autonomic regulation also play a key contributing role. The purpose of this review is to examine the physiological factors that contribute to neurocirculatory dysregulation during exercise and discuss the adaptations that result from regular exercise training in CKD. Key neurocirculatory mechanisms contributing to exercise intolerance in CKD include augmentation of the exercise pressor reflex, aberrations in neurocirculatory control, and increased neurovascular transduction. In addition, we highlight how some contributing factors may be improved through exercise training, with a specific focus on the sympathetic nervous system. Important areas for future work include understanding how the exercise prescription may best be optimized in CKD and how the beneficial effects of exercise training may extend to the brain.

Aerobic exercise training improves endothelial function and attenuates blood pressure reactivity during maximal exercise in chronic kidney disease

Patients with chronic kidney disease (CKD) have exaggerated increases in blood pressure during exercise that are associated with endothelial dysfunction. We hypothesized that aerobic exercise training would improve endothelial function and attenuate blood pressure reactivity during exercise in CKD. Sedentary individuals with CKD stages III-IV underwent 12 wk of aerobic cycling exercise (n = 26) or nonaerobic exercise (n = 22, control). Both interventions were performed 3 days/wk and matched for duration. Endothelial function was measured via peripheral arterial tonometry and quantified as reactive hyperemia index (RHI). Peak oxygen uptake (V̇o_2peak) was assessed via maximal treadmill exercise testing with concomitant blood pressure monitoring. All measurements were performed at baseline and after the 12-wk intervention. A linear mixed model was used to compare the rate of increase in blood pressure during the test. RHI improved with exercise (Pre = 1.78 ± 0.10 vs. Post = 2.01 ± 0.13, P = 0.03) with no change following stretching (Pre = 1.73 ± 0.08 vs. Post = 1.67 ± 0.10, P = 0.69). Peak systolic blood pressure during the maximal treadmill exercise test was lower after exercise training (Pre = 186 ± 5 mmHg, Post = 174 ± 4 mmHg, P = 0.003) with no change after stretching (Pre = 190 ± 6 mmHg, Post = 190 ± 4 mmHg, P = 0.12). The rate of increase in systolic blood pressure during the V̇o_2peak test tended to decrease after training for both groups (-2 mmHg/stage) with no differences between groups (P = 0.97). There was no change in V̇o_2peak after either intervention. In conclusion, aerobic exercise training improves endothelial function and attenuates peak blood pressure reactivity during exercise in CKD.NEW & NOTEWORTHY Patients with chronic kidney disease (CKD) exhibit increased blood pressure reactivity during exercise that is associated with endothelial dysfunction. Twelve weeks of structured, aerobic, exercise training improves endothelial function and attenuates peak blood pressure responses during exercise in CKD stages III-IV.

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.

Cardiorespiratory Fitness, Workload, and the Blood Pressure Response to Exercise Testing

ABSTRACT

We propose that for correct clinical interpretation of exaggerated exercise blood pressure (EEBP), both cardiorespiratory fitness and exercise workload must be considered. A key recommendation towards achieving the correct clinical interpretation of EEBP is that exercise BP should be measured during submaximal exercise with a fixed external workload.

Improvement in functional capacity with spironolactone masks the treatment effect on exercise blood pressure

OBJECTIVES

A hypertensive response to submaximal exercise is associated with cardiovascular disease but this relationship is influenced by functional capacity. Spironolactone improves functional capacity, which could mask treatment effects on exercise blood pressure. This study sought to examine this hypothesis.

DESIGN

Retrospective analysis of a randomized clinical trial.

METHODS

102 participants (54 ± 9 years; 52% male) with a hypertensive response to maximal exercise (systolic BP ≥210 mm Hg men; ≥190 mm Hg women) were randomized to 3-month spironolactone 25 mg daily (n = 53) or placebo (n = 49). Submaximal exercise blood pressure was measured during low-intensity cycling (50, 60 or 70% age-predicted maximal heart rate). Functional capacity was measured as maximal oxygen capacity obtained during a maximal treadmill exercise test, and (resting) aortic stiffness by carotid-to-femoral pulse wave velocity.

RESULTS

Spironolactone improved submaximal exercise systolic blood pressure vs. placebo (-4 ± 16 vs. 2 ± 15 mm Hg, p = 0.045, Cohen's d = 0.42), and had a small (but non-statistically significant) improvement in functional capacity (0.64 ± 5.10 vs. -1.43 ± 5.04 ml/kg/min, p = 0.06, Cohen's d = 0.4). When treatment effects were expressed as the change in submaximal exercise systolic blood pressure relative to the change in functional capacity, a larger effect size was observed (-0.3 ± 1.1 vs. 0.3 ± 1.1 mm Hg/ml·kg·min^-1, p = 0.01, Cohen's d = 0.58), but was not explained by improved aortic stiffness.

CONCLUSIONS

Spironolactone reduces submaximal exercise blood pressure, but this treatment effect may be hidden by improved functional capacity and a non-fixed workload. This highlights the most clinically relevant exercise blood pressure is at a low intensity and fixed workload where the influence of fitness on exercise blood pressure is removed, and the effects of therapy can be appreciated.

Novel insights into stroke risk beyond resting and maximal bicycle exercise systolic blood pressure

OBJECTIVE

Previous research has shown an association between moderate workload exercise blood pressure (BP) and coronary disease, whereas maximal exercise BP is associated with stroke. We aimed to investigate the association between the increase in BP during maximal exercise and the long-term risk of stroke in healthy, middle-aged men.

METHODS

Two thousand and fourteen men were included in the Oslo Ischemia Study in the 1970s. In the present study, we examined baseline data of the 1392 participants who remained healthy and performed bicycle exercise tests both at baseline and 7 years later. Cox proportional hazard was used to assess the risk of stroke in participants divided into quartiles based on the difference between resting and maximal workload SBP (ΔSBP) at baseline, adjusting for resting BP, age, smoking, serum cholesterol and physical fitness. Follow-up was until the first ischemic or hemorrhagic stroke through 35 years.

RESULTS

There were 195 incident strokes; 174 (89%) were ischemic. In univariate analyses, there were significant positive correlations between age, resting SBP, resting DBP and SBP at moderate and maximal workload, and risk of stroke. In the multivariate analysis, there was a 2.6-fold (P < 0.0001) increase in risk of stroke in ΔSBP quartile 4 (ΔSBP > 99 mmHg) compared with ΔSBP quartile 2 (ΔSBP 73-85 mmHg), which had the lowest risk of stroke. ΔSBP quartile 1 had a 1.7-fold (P = 0.02) increased risk compared with quartile 2, suggesting a J-shaped association to stroke risk.

CONCLUSION

Stroke risk increased with increasing difference between resting and maximal exercise SBP, independent of BP at rest, suggesting that an exaggerated BP response to physical exercise may be an independent predictor of stroke.

Augmented exercise pressor response during maximal treadmill exercise is not related to systemic inflammation in stroke survivors

BACKGROUND

Stroke survivors have exercise intolerance that contributes to reduced quality of life and survival. While exaggerated blood pressure responses during exercise have been documented in other chronic diseases, whether stroke patients have abnormal hemodynamic responses during aerobic exercise remains unexplored.

OBJECTIVES

This cross-sectional study aimed to examine whether stroke survivors have exaggerated increases in blood pressure during maximal treadmill exercise and whether these responses may be related to systemic inflammation.

METHODS

Forty-six participants (25 stroke survivors, STROKE, and 21 controls, CON) performed a maximal treadmill exercise test via the modified Naughton protocol while blood pressure was measured manually during each treadmill stage. A linear mixed model was used to compare the slope of rise in heart rate and blood pressure within and between groups. Spearmans rho analysis was performed to explore the relationship between these responses and circulating concentrations of inflammatory biomarkers.

RESULTS

The STROKE group exhibited a lower VO₂peak (16.4 ± 0.8 vs. 30.0 ± 1.8 ml/kg/min, P < .001) and a greater rate of increase in systolic blood pressure compared to CON (17.4 ± 1.5 vs. 9.9 ± 1.4 mmHg/stage, P < .001). We observed no relationship; however, between inflammatory biomarkers and the exaggerated hemodynamic responses in the STROKE group.

CONCLUSION

In conclusion, stroke survivors exhibit greater increases in systolic blood pressure during maximal treadmill exercise compared to controls. These responses do not appear to be related to systemic inflammation. Future work should seek to delineate the mechanisms responsible for exaggerated blood pressure responses during exercise in stroke.

Exercise Systolic Blood Pressure at Moderate Workload Is Linearly Associated With Coronary Disease Risk in Healthy Men

There is no consensus on the definition of an exaggerated increase in systolic blood pressure (SBP) during exercise. The aim was to explore a potential threshold for exercise SBP associated with increased risk of coronary heart disease in healthy men using repeated exercise testing. Two thousand fourteen healthy white male employees were recruited into the Oslo Ischemia Study during early 1970s. At follow-up 7 years later, 1392 men were still considered healthy. A bicycle exercise test at 100 W workload was performed at both visits. Cox regression analyses were performed with increasing cutoff levels of peak exercise SBP at 100 W workload (SBP100W) from 160 mm Hg to 200 mm Hg, adjusted for cardiovascular risk factors and physical fitness. Participants with SBP100W below cutoff level at both baseline and first follow-up were compared with participants with SBP100W equal to or above cutoff level at both visits. Compared with participants with SBP100W below all cutoff levels between 165 and 195 mm Hg, coronary heart disease risk was increased among participants with SBP100W equal to or above cutoff at all levels. There was no evidence of a distinct threshold level for coronary heart disease risk, and the relation between SBP100W and coronary heart disease appears linear. When investigating exercise SBP at moderate workload measured at 2 exercise tests in healthy middle-aged white men, there is increasing risk of coronary heart disease with increasing exercise SBP independent of SBP at rest. The association is linear from the low range of exercise SBP, and there is no sign of a distinct threshold level for increased coronary disease risk.

Association of elevated blood pressure during exercise with cerebral white matter lesions

OBJECTIVES

Cerebral white matter lesions (WMLs) are regarded to be subclinical ischemic changes of the cerebral parenchyma. Many previous studies have shown that baseline blood pressure (BP) is one of the most important factors for WMLs, but the relation between exercise BP and WMLs has not been fully evaluated. So, we sought to investigate the relationships between cerebral WMLs and peak exercise BP.

METHODS

Brain magnetic resonance imaging scan and treadmill testing were performed simultaneously in 130 consecutive subjects without history of stroke or transient ischemic stroke.

RESULTS

Among 130 subjects, 42 individuals (32%) presented WMLs. Individuals with WMLs were older than those without WMLs, and baseline systolic BP and pulse pressure were higher in subjects with WMLs. During treadmill test, peak exercise systolic BP was more significantly elevated in subjects with WMLs. In multivariable logistic regression analysis, elevated baseline systolic BP, not peak exercise systolic BP, was associated with the presence of WMLs, independently of age. However, in multivariable logistic regression analysis of 88 normotensive subjects, elevated peak systolic BP during exercise was the only determinant for the presence of WMLs.

CONCLUSIONS

Elevated peak systolic BP during exercise is significantly related with WMLs, subclinical small vessel disease of brain, especially in normotensive subjects.