Cognitive decline in heart failure: Biomolecular mechanisms and benefits of exercise

By definition, heart failure (HF) is a human pathological condition affecting the structure and function of all organs in the body, and the brain is not an exception to that. Failure of the heart to pump enough blood centrally and peripherally is at the foundation of HF patients' inability to attend even the most ordinary daily activities and progressive deterioration of their cognitive capacity. What is more, between heart and brain exists a bidirectional relationship that goes well beyond hemodynamics and concerns bioelectric and endocrine signaling. This increasingly consolidated evidence makes the scenario even more complex. Studies have mainly chased how HF impairs cognition without focusing much on preventive measures, notably cardio-cerebral health proxies. Here, we aim to provide a brief account of known and hypothetical factors that may explain how exercise can help obviate cognitive dysfunction associated with HF in its different forms. As we shall see, there is a stringent need for a deeper grasp of such mechanisms. Indeed, gaining this new knowledge will automatically shed new light on the inner workings of HF itself, thus resulting in more effective prevention and treatment of this escalating syndrome.

Effects of an individualized and progressive multicomponent exercise program on blood pressure, cardiorespiratory fitness, and body composition in long-term care residents: Randomized controlled trial

This study analyzed the effects of an individualized and progressive multicomponent exercise program on blood pressure, cardiorespiratory fitness, and body composition in long-term care residents. This was a single-blind, multicenter, randomized controlled trial performed in 10 long-term care settings and involved 112 participants. Participants were randomly assigned to a control group or an intervention group. The control group participated in routine activities; the intervention group participated in a six-month individualized and progressive multicomponent exercise program focused on strength, balance, and walking recommendations. The intervention group maintained peak VO₂, oxygen saturation, and resting heart rate, while the control group showed a significant decrease in peak VO₂ and oxygen saturation and an increase in resting heart rate throughout the six-month period. Individualized and progressive multicomponent exercise programs comprising strength, balance, and walking recommendations appear to be effective in preventing cardiorespiratory fitness decline in older adults living in long-term care settings.

Impaired heart rate recovery as a predictor for poor health-related quality in patients with transient ischemic attack

We aimed to investigate heart rate recovery (HRR) in patients with transient ischemic attack (TIA) and the relationship between HRR and health-related quality of life (HRQOL).All available patients were enrolled during the enrollment period. A total of 120 patients with TIA and 120 healthy controls were included in this study. A treadmill stress test was performed to calculate the HRR. The HRR were calculated as follows: HRR 1, 2, 3, and 5 minutes = heart rate at peak during exercise - heart rate at 1, 2, 3, and 5 minutes at rest. All patients enrolled were asked to fill in the Short Form 36 Health Survey to calculate HRQOL.We found that the maximum heart rate of TIA patients was significantly higher than that of healthy controls (166 ± 11 vs. 162 ± 14 beats/min, P = .015). Similarly, maximum systolic blood pressure (SBP) and diastolic blood pressure (DBP) were higher in TIA group compared with healthy control group (SBP: 172 ± 15 vs. 165 ± 14 mm Hg, P < .001; DBP: 102 ± 12 vs. 93 ± 16 mm Hg, P < .001). The HRR were significantly lower in TIA group compared with control group (TIA vs. controls, HRR1: 17 ± 7 vs. 30 ± 8 beats/min, HRR2: 32 ± 11 vs. 49 ± 9 beats/min, HRR3: 43 ± 13 vs. 63 ± 12 beats/min, HRR5: 54 ± 16 vs. 73 ± 15 beats/min, all P < .001). Multivariate analysis showed that older age (P = .03) and high BMI (P = .04) were risk factors associated with abnormal HRR in patients with TIA. With regard to HRQOL, we found that role limitations due to physical problems, general health, vitality, and role limitations due to emotional problems were significantly lower in patients with abnormal HRR compared with patients with normal HRR. Multivariate analysis showed that older age (P = .04) and abnormal HRR (P = .03) were predictors for poor HRQOL in TIA patients.HRR was impaired in patients with TIA. In addition, TIA patients with abnormal HRR suffered from a significantly poorer HRQOL. Hence, given the prognostic value of HRR, patients with TIA should be monitored to prevent cardiovascular events and to improve HRQOL.

Influence of exercise on oxidative stress in patients with heart failure

Reactive oxygen species play an important role in the pathophysiology of heart failure (HF). In contrast, regular physical exercise can promote adaptations to reactive oxygen species that are beneficial for patients with HF. We completed a systematic review of randomized controlled trials that evaluate the influence of exercise on oxidative stress in patients with HF. Articles were searched in the PubMed, Cochrane, SciELO, and LILACS databases. The search was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The quality of the included studies was assessed using the Physiotherapy Evidence Database scale. We selected 12 studies with a total of 353 participants. The included patients had a left ventricle ejection fraction of < 52% and New York Heart Association functional class II or III disease. A significant increase was observed in peak oxygen consumption (between 10 and 46%) in the group that underwent training (TG). There was an improvement in the oxidative capacity of skeletal muscles in the TG, related to the positive activity of mitochondrial cytochrome c oxidase (between 27 and 41%). An increase in the expression of the enzymes glutathione peroxidase (41%), catalase (between 14 and 42%), and superoxide dismutase (74.5%), and a decrease in lipid peroxidation (between 28.8 and 58.5%) were observed in the TG. Physical training positively influenced the cardiorespiratory capacity and enhanced the benefits of oxidant and antioxidant biomarkers in patients with HF. High-intensity training promoted a 15% increase in the plasma total antioxidant capacity, whereas moderate training had no effect.

Effects of Low-Intensity Exercise in Older Adults With Chronic Heart Failure During the Transitional Period From Hospital to Home in China: A Randomized Controlled Trial

The transitional period from hospital to home is critical to decreasing rates of preventable, poor post-discharge outcomes. Older adults with chronic heart failure (CHF) may be challenged to exercise during the transitional period. The purpose of the current study was to test the effects of low-intensity exercise on health-related quality of life (HRQoL), physical function, and heart function in Chinese older adults with CHF during the transitional period. The study was randomized, single-blinded, and controlled. Seventy-eight older adults with stable CHF were evaluated. The intervention group (n = 41) participated in a regular low-intensity walking protocol and the control group (n = 38) did not. Measures included the Minnesota Living with Heart Failure Questionnaire (MLHFQ), 6-minute walk distance (6MWD), Timed Up and Go (TUG) test, resting heart rate (RHR), and left ventricular ejection fraction (LVEF). After 12 weeks, the intervention group showed significant improvements in MLHFQ, 6MWD, and TUG scores compared to the control group (p < 0.05), and no significant improvements in RHR and LVEF (p > 0.05). Low-intensity exercise during the transitional period is an effective way to improve HRQoL and physical function in older adults. [Res Gerontol Nurs. 2017; 10(3):121-128.].

The effects of baseline heart rate recovery normality and exercise training protocol on heart rate recovery in patients with heart failure

Objective:

It is unclear which exercise training protocol yields superior heart rate recovery (HRR) improvement in heart failure (HF) patients. Whether baseline HRR normality plays a role in the improvement is unknown. We hypothesized that an exercise training protocol and baseline HRR normality would be factors in altering HRR in HF patients.

Methods:

In this prospective, randomized, controlled and 3 group parallel study, 41 stable HF patients were randomly assigned to 3-times-weekly training sessions for 12 weeks, consisting of i) 30 minutes of interval training (IT) (n=17, 63.7±8.8 years old) versus ii) 30 minutes of continuous training (CT) (n=13, 59.6±6.8 years old) versus iii) no training (CON) (n=11, 60.6±9.9 years old). Each patient had cardiopulmonary exercise testing before and after the training program. Maximum heart rates attained during the test and heart rates at 1 and 2 min (HRR1 and HRR2) during the recovery phase were recorded. Paired samples t-test or Wilcoxon signed-rank test was used for comparisons before and after training. One-way ANOVA or Kruskal-Wallis variance analysis was used for comparisons among groups.

Results:

HRR1 was unchanged after training. HRR2 improved in the IT group after training, and post-training HRR2 values were significantly faster in the IT group than in controls. Both HRR1 and HRR2 was significantly faster, irrespective of exercise protocol in patients with abnormal baseline values after training.

Conclusion:

HRR1 did not improve after training. HRR2 improved only in the IT group. Both HRRs in patients with abnormal baseline values improved after both exercise protocols. IT might be superior to CT in improving HRR2. Baseline HRR might play a role in its response to exercise.

Life activities improve heart rate variability in patients with mild hypertension and/or the initial stage of heart failure

AIMS AND OBJECTIVES

To determine the effects on heart rate variability of home-based daily activity in patients with mild hypertension and/or stable angina pectoris and to clarify the relationship between daily activity and sympathovagal balance.

BACKGROUND

Several prior studies have assessed the ability of exercise training to improve functional capacity and produce beneficial effects on mortality and physical capacity in patients with cardiovascular disease.

DESIGN

A non-randomised six-month prospective longitudinal study.

METHODS

This study consisted of 41 patients (59-83 years old) with mild hypertension and/or stable angina pectoris. The home-based daily activity and heart rate variability were measured at the start of the study (BASE) and six months after the start of the study (6MoA). At 6MoA, the active mass increased in 23 patients (the IC group), while it decreased in the remaining 18 patients (the DC group).

RESULTS

There were significant increases in the high-frequency component in the IC group between the data at BASE and 6MoA. There were significant decreases in the low frequency to high-frequency ratio (low frequency/high-frequency) during sleep in the IC group between the data at BASE and 6MoA. The active mass was classified into life activities and walk activities in terms of intensity of activity. In a multivariate model, increased life activitiesrevealed a trend towards an association with increased high-frequency.

CONCLUSIONS

In patients with mild hypertension and/or stable angina pectoris, an increase in active mass improved heart rate variability outcomes with increased high-frequency and decreased low frequency/high-frequency during sleep. To increase life activitiesmight improve heart rate variability and prognosis in patients.

RELEVANCE TO CLINICAL PRACTICE

This study demonstrated that the potential importance of low-intensity daily activities in patients with mild hypertension and/or stable angina pectoris.

Impact of physical activity on inflammation: effects on cardiovascular disease risk and other inflammatory conditions

Since the 19(th) century, many studies have enlightened the role of inflammation in atherosclerosis, changing our perception of "vessel plaque due to oxidized lipoproteins", similar to a "rusted pipe", towards a disease with involvement of many cell types and cytokines with more complex mechanisms. Although "physical activity" and "physical exercise" are two terms with some differences in meaning, compared to sedentary lifestyle, active people have lower cardiovascular risk and lower inflammatory markers. Activities of skeletal muscle reveal "myokines" which have roles in both the immune system and adipose tissue metabolism. In vitro and ex-vivo studies have shown beneficial effects of exercise on inflammation markers. Meanwhile in clinical studies, some conflicting results suggested that type of activity, exercise duration, body composition, gender, race and age may modulate anti-inflammatory effects of physical exercise. Medical data on patients with inflammatory diseases have shown beneficial effects of exercise on disease activity scores, patient well-being and inflammatory markers. Although the most beneficial type of activity and the most relevant patient group for anti-inflammatory benefits are still not clear, studies in elderly and adult people generally support anti-inflammatory effects of physical activity and moderate exercise could be advised to patients with cardiovascular risk such as patients with metabolic syndrome.

Elevated homocysteine is associated with poorer self-perceived physical health in older men: the Health in Men Study

OBJECTIVES

To determine the relationship between high total homocysteine (tHcy) and self-perceived physical health, by investigating the associations between tHcy, the methylenetetrahydrofolate reductase (MTHFR) 677T polymorphism and physical health-related quality of life (HRQOL).

STUDY DESIGN

We conducted a cross-sectional study using a cohort of 4248 community-dwelling men aged 70-88 years.

MAIN OUTCOME MEASURES

In addition to clinical determinants of physical health, tHcy was measured by immunoassay, the MTHFR 677T polymorphism was detected by a polymerase chain reaction (PCR)-based method, and physical HRQOL were assessed with the SF-36 Health Survey.

RESULTS

In multiple regression analyses, the odds of being in the lowest quartile of the physical component summary (PCS) scores (i.e. <35) was 1.47 (95% CI 1.21-1.78) for men with high tHcy (≥15 μmol/l), after adjusting for age, smoking, history of hazardous alcohol use, polypharmacy, prevalent falls and weighted Charlson co-morbidity index. When history of hypertension, heart disease, stroke, arthritis and osteoporosis were included in place of the Charlson's index, the result was unchanged (OR 1.45, 95% CI 1.20-1.75). Men with the MTHFR TT homozygosity had significantly higher tHcy concentration than those with the CC genotype (mean difference of 1.38 μmol/l, 95% CI 0.77-1.99). However, there was no apparent association between the MTHFR polymorphism and PCS.

CONCLUSION

Elevated tHcy is associated with poorer self-perceived physical health in community-dwelling older men. The results of this study support further longitudinal investigations to assess this relationship prospectively.

The effect of diet and exercise on markers of endothelial function in overweight and obese women with polycystic ovary syndrome

BACKGROUND

Women with polycystic ovary syndrome (PCOS) present with vascular abnormalities, including elevated markers of endothelial dysfunction. There is limited evidence for the effect of lifestyle modification and weight loss on these markers. The aim of this study was to determine if 20 weeks of a high-protein energy-restricted diet with or without exercise in women with PCOS could improve endothelial function.

METHODS

This is a secondary analysis of a subset of 50 overweight/obese women with PCOS (age: 30.3 ± 6.3 years; BMI: 36.5 ± 5.7 kg/m(2)) from a previous study. Participants were randomly assigned by computer generation to one of three 20-week interventions: diet only (DO; n = 14, ≈ 6000 kJ/day), diet and aerobic exercise (DA; n = 16, ≈ 6000 kJ/day and five walking sessions/week) and diet and combined aerobic-resistance exercise (DC; n = 20, ≈ 6000 kJ/day, three walking and two strength sessions/week). At Weeks 0 and 20, weight, markers of endothelial function [vascular cell adhesion molecule-1 (sVCAM-1), inter-cellular adhesion molecule-1 (sICAM-1), plasminogen activator inhibitor-1 (PAI-1) and asymmetric dimethylarginine (ADMA)], insulin resistance and hormonal profile were assessed.

RESULTS

All three treatments resulted in significant weight loss (DO 7.9 ± 1.2%, DA 11.0 ± 1.6%, DC 8.8 ± 1.1; P < 0.001 for time; P = 0.6 time × treatment). sVCAM-1, sICAM-1 and PAI-1 levels decreased with weight loss (P≤ 0.01), with no differences between treatments (P ≥ 0.4). ADMA levels did not change significantly (P = 0.06). Testosterone, sex hormone-binding globulin and the free androgen index (FAI) and insulin resistance also improved (P < 0.001) with no differences between treatments (P ≥ 0.2). Reductions in sVCAM-1 were correlated to reductions in testosterone (r = 0.32, P = 0.03) and FAI (r = 0.33, P = 0.02) as well as weight loss (r= 0.44, P = 0.002). Weight loss was also associated with reductions in sICAM-1 (r= 0.37, P = 0.008).

CONCLUSIONS

Exercise training provided no additional benefit to following a high-protein, hypocaloric diet on markers of endothelial function in overweight/obese women with PCOS.

Dynamic assessment of ventilatory efficiency during recovery from peak exercise to enhance cardiopulmonary exercise testing

BACKGROUND

While cardiopulmonary exercise testing (CPX) assessment is generally regarded as an optimal means to assess functional capacity in heart failure (HF) patients, strength parameters are omitted. CPX indices collected in recovery may provide additional insight regarding function, including strength.

DESIGN AND METHODS

We performed a cross-sectional controlled study. Systolic HF patients (aged ≥ 50 years) and age-matched controls were assessed using CPX and strength evaluations. Standard CPX indices were assessed during exercise (peak oxygen consumption [VO2], first ventilatory threshold [1stVT], and ventilatory efficiency [VE/VCO2 slope]) as well as indices at 1-minute recovery (1 min VO2, 1 min VE/VCO2, and 1 min heart rate recovery [HRR]) and differences between peak and 1-minute recovery (ΔVO₂ and ΔVE/VCO₂). Lower extremity strength was evaluated using the 1-repetition maximum (1RM) and power.

RESULTS

Seventy adults (31 HF; 39 controls), mean age 66.2 ± 9.7 years were evaluated. Peak VO2 (15.4 ± 4.2 versus 23.4 ± 6.6 mlO₂·kg(-1)·min(-1), p < 0.0001) and 1stVT (10.9 ± 2.1 versus 14.4 ± 4.0 mlO₂·kg(-1)·min(-1), p < 0.0001) were diminished in HF versus controls and VE/VCO2 slope was increased (42.3 ± 12.2 versus 35.4 ± 8.3, p < 0.01). HF patients had reduced 1 minVO₂ (13.1 ± 2.9 versus 16.3 ± 3.7 mlO₂·kg(-1)·min(-1), p < 0.0001), 1 min HRR (6.7 ± 11.4 versus 12.4 ± 7.6 beats, p < 0.02), and ΔVO₂ (2.43 ± 2.3 versus 7.3 ± 5.0 mlO₂·kg(-1)·min(-1), p < 0.0001) as well as increased 1 min VE/VCO2 (37 ± 7.5 versus 31.5 ± 4.4, p < 0.001) and ΔVE/VCO₂ (1.17 ± 3.0 versus -0.5 ± 1.3, p < 0.0001). Strength parameters were relatively lower in HF. While CPX exercise parameters correlated with strength, stronger correlations were observed between CPX recovery parameters and strength.

CONCLUSIONS

CPX recovery indices corroborate disease-specific aerobic differences and distinguish differences in strength. Recovery ventilatory efficiency enhances CPX's value as a comprehensive physical function tool.