Functional capacity in patients with congestive heart failure

The Evaluation of Functional Abilities Using the Modified Fullerton Functional Fitness Test Is a Valuable Accessory in Diagnosing Men with Heart Failure

The assessment of functional abilities reflects the ability to perform everyday life activities that require specific endurance and physical fitness. The Fullerton functional fitness test (FFFT) seems to be the most appropriate for assessing physical fitness in heart failure (HF) patients. The study group consisted of 30 consecutive patients hospitalized for the routine assessment of HF with a reduced ejection fraction (HFrEF). They formed the study group, and 24 healthy subjects formed the control group. Each patient underwent a cardiopulmonary exercise test (CPET), transthoracic echocardiography and FFFT modified by adding the measurement of the handgrip force of the dominant limb with the digital dynamometer. The HF patients had significantly lower peak oxygen uptake (peakVO2), maximal minute ventilation, and higher ventilatory equivalent (VE/VCO2). The concentrations of B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) were significantly higher in the study group. The results of all the FFFT items were significantly worse in the study group. FFFT parameters, together with the assessment of the strength of the handgrip, strongly correlated with the results of standard tests in HF. FFFT is an effective and safe tool for the functional evaluation of patients with HFrEF. Simple muscle strength measurement with a hand-held dynamometer can become a convenient and practical indicator of muscle strength in HF patients.

Is Skeletal Muscle Dysfunction a Limiting Factor of Exercise Functional Capacity in Patients with Sickle Cell Disease?

Patients with sickle cell disease (SCD) have reduced functional capacity due to anemia and cardio-respiratory abnormalities. Recent studies also suggest the presence of muscle dysfunction. However, the interaction between exercise capacity and muscle function is currently unknown in SCD. The aim of this study was to explore how muscle dysfunction may explain the reduced functional capacity. Nineteen African healthy subjects (AA), and 24 sickle cell anemia (SS) and 18 sickle cell hemoglobin C (SC) patients were recruited. Maximal isometric torque (Tmax) was measured before and after a self-paced 6-min walk test (6-MWT). Electromyographic activity of the Vastus Lateralis was recorded. The 6-MWT distance was reduced in SS (p < 0.05) and SC (p < 0.01) patients compared to AA subjects. However, Tmax and root mean square value were not modified by the 6-MWT, showing no skeletal muscle fatigue in all groups. In a multiple linear regression model, genotype, step frequency and hematocrit were independent predictors of the 6-MWT distance in SCD patients. Our results suggest that the 6-MWT performance might be primarily explained by anemia and the self-paced step frequency in SCD patients attempting to limit metabolic cost and fatigue, which could explain the absence of muscle fatigue.

Measuring quality of life in advanced heart failure

PURPOSE OF REVIEW

Patients with Stage D heart failure can benefit from palliative care consultation to help them manage unpleasant symptoms and improve quality of life. Although guidelines describe how to manage symptoms, very little direction is provided on how to evaluate the effectiveness of those interventions.

RECENT FINDINGS

Numerous studies have used the measurement of symptoms, emotional distress, functional capacity and quality of life to evaluate the effectiveness of interventions in heart failure. There is limited evidence on the use of these instruments in heart failure palliative care. Four studies were identified that evaluate the effectiveness of palliative care consultation for patients with advanced heart failure. All four studies measured symptom severity, emotional distress, and quality of life. The application of appropriate instruments is discussed. Suggestions for scores that should trigger palliative care consultation are identified.

SUMMARY

The routine administration of standardized instruments to measure symptom severity and quality of life may improve the assessment and management of patients with Stage D heart failure. Ongoing discussion and research is needed to determine if these instruments are the best tools to use with heart failure palliative care patients.

Sit-to-stand test and 6-min walking test correlation in patients with chronic obstructive pulmonary disease

BACKGROUND:

The 6-min walking test (6MWT) is one of the most commonly used tests to assess exercise capacity during chronic obstructive pulmonary disease (COPD). However, it is a relatively time-consuming test. Many authors assessed the usefulness of simpler methods, as the sit-to-stand test (STST), to estimate exercise capacity.

PURPOSE:

To demonstrate the feasibility of STST, in comparison to 6MWT, for the evaluation of functional status in Tunisian COPD patients and evaluate its correlation to the severity of the disease.

METHODS:

We studied patients with COPD (Global Initiative for Chronic Obstructive Lung Disease A-D). All patients had plethysmography and manual quadriceps femoris muscle strength evaluation. Each patient completed a 6MWT and a STST. During the tests, dyspnea severity (Borg scale), heart rate, pulsed oxygen saturation, and blood pressure were measured.

RESULTS:

In 49 patients with stable COPD (mean age 67.06 ± 8.4 years, mean forced expiratory volume in the first second 46.25% ± 19.64%), 6MWT and STST were correlated with each other (r = 0.47, P = 0.001). During 6MWT and STST, the rise in heart rate, systolic blood pressure, and severity of dyspnea were statistically significant compared to baseline (P < 0.05). However, cardiorespiratory stress was lower after STST than after 6MWT (P < 0.05). A statistically significant positive correlation was noted between the 6MWT distance and forced vital capacity (r = 0.357, P < 0.05). The 6MWT was negatively correlated with dyspnea severity at baseline (r = −0.289, P < 0.05) and with BODE index (r = −0.672, P < 0.01). STST was correlated only with age (r = 0.377, P < 0.01). No correlation was found between both tests and quadriceps femoris strength.

CONCLUSION:

As like as 6MWT, STST can determine functional status during COPD. In addition, it is less time consuming and produces less hemodynamical stress compared to 6MWT. STST can be used as an alternative for 6MWT in patients with COPD.

Low serum IL-6 is associated with high 6-minute walking performance in asymptomatic women aged 20 to 70years

Cross-sectional associations between low physical performance and inflammatory biomarkers have been reported in healthy subjects and in persons with specific disease conditions. In asymptomatic subjects, whether the inverse association between physical fitness and inflammatory biomarkers is dependent or is independent of fat mass, a significant source of inflammatory cytokines, and is independent of age, muscle mass and strength, endocrine, metabolic, and lifestyle factors is not known. Two hundred and twenty asymptomatic women aged 20 to 72years with a C-reactive protein <5mg/L were assessed for their mean speed over the 6-minute walking test (6MWS) and their serum IL-6, as well as body height, body weight, body lean and fat mass (measured by DXA), waist-to-hip ratio, grip and knee extension strength, physical activities (quantified by the QUANTAP questionnaire), tobacco consumption, serum 25(OH) vitamin D, parathyroid hormone (PTH), estradiol (E2), free testosterone, dehydroepiandrosterone sulfate (DHEAS), insulin-like growth factor (IGF-I), sex hormone-binding globulin (SHBG), calcium, albumin, and creatinine. In the stepwise multiple linear regression model, a 6MWS in the highest quartile (over 1.4m/s) was associated with lower values of serum IL-6 (p=0.02) and with higher values of grip strength (p=0.04) and creatinine (p=0.04). In conclusion, present results demonstrate that the relationship between lower levels of serum IL-6 and higher values of physical fitness in asymptomatic women is independent of age, body composition, and lifestyle, endocrine and metabolic confounders. It remains to be determined whether the inverse relationship between IL-6 and fitness reflects the presence of preclinical inflammatory diseases that could potentially influence fitness in asymptomatic women.

The 6-min walk test: is it an effective method for evaluating heart failure therapies?

The 6-min walk (6MW) is a self-paced test for measuring functional capacity. Lower 6MW distances have been associated with adverse outcomes in patients with heart failure. The purpose of this article is to describe the history of the 6MW test and to evaluate its reliability, validity, and predictive value as well as the responsiveness of the test to therapies. In the literature we reviewed, reliability was affected by several factors including learning effects and protocol deviations. The 6MW distance was moderately correlated with peak oxygen consumption derived from cardiopulmonary exercise stress testing. In some studies the 6MW distance was predictive of hospitalization and mortality. In pharmacological and cardiac resynchronization trials the 6MW distance did not consistently detect clinical improvements. Despite limitations, the 6MW test is a viable alternative to stress testing for objectively evaluating functional capacity in some settings. We provide recommendations for using the 6MW test in future studies.

Predicting exercise capacity through submaximal fitness tests in persons with multiple sclerosis

OBJECTIVE

To estimate, for persons with multiple sclerosis (MS), the extent to which peak oxygen consumption (Vo(2)peak) can be predicted by the results on submaximal tests.

DESIGN

Cross-sectional study.

SETTING

Three MS clinics in the Greater Montreal region, Canada.

PARTICIPANTS

A center-stratified random sample of 135 women and 48 men was drawn (N=183). A subgroup of 59 subjects with MS, who were able to perform the step test, was selected from this sample to complete the maximal exercise test.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

Vo(2)peak.

RESULTS

In this sample (mean age +/- SD, 39 +/- 9 y; median Expanded Disability Status Scale=1.5), the mean Vo(2)peak +/- SD was 27.6 +/- 7.3 mL.kg(-1).min(-1). This value is considerably low when compared with healthy persons, ranking below the 25th percentile for both men and women. In a multivariate regression analysis, the step test and grip strength were identified as the only significant predictors of Vo(2)peak. When combined with body weight, grip strength and the step test explained 74% of the variance in Vo(2)peak.

CONCLUSIONS

Patients with MS with a mild degree of disability exhibit marked reductions in exercise capacity. Also, in persons with MS, submaximal tests are good predictors of exercise capacity. These measures may be used in clinical settings to help assess and monitor maximum oxygen consumption and in research to evaluate the effect of exercise-related interventions. Furthermore, they will allow people with MS to self-monitor their exercise capacity and be more actively engaged in taking charge of their fitness level.

Factors related to time to admission to specialized multidisciplinary clinics in patients with congestive heart failure

BACKGROUND

Congestive heart failure (CHF) is a common cause of hospitalization and has a poor prognosis. Specialized multidisciplinary clinics are effective in the management of CHF.

OBJECTIVES

To measure time of admission to the specialized clinics and explore factors related to the time of admission to these clinics.

METHODS

Patients who were newly admitted to one of six CHF multidisciplinary clinics in the province of Quebec were enrolled in the study. Data were collected from the common clinical database used at these clinics as well as from questionnaires administered to the patients.

RESULTS

A total of 531 patients with a mean age of 65.9 years were enrolled. Only 26% were women. The median duration of disease before admission to the CHF clinic was 1.2 years. The majority of patients (62%) were referred by a cardiologist or an internist, while 24% were referred by other specialists, and 14% by general practitioners. One-fifth of patients did not have regular follow-up for their CHF before being admitted to the clinic. Factors associated with shorter disease duration at admission to the clinic were referral by a specialist, not having regular medical follow-up for CHF, having a higher income and having visited the emergency room for CHF.

CONCLUSION

There may be a need to improve dissemination of information regarding availability and benefits of CHF clinics and criteria for referral.

Six minute walk test: a simple and useful test to evaluate functional capacity in patients with heart failure

In heart failure survival is closely related to functional capacity. Peak O2 consumption at cardiopulmonary exercise test (CPET) is considered the gold standard for the evaluation of exercise tolerance. Since >70% of patients with heart failure, usually elderly or with significant comorbidities, are referred to Departments of Internal Medicine where facilities for cardiopulmonary test are rarely available, CPET may be performed in <5% of the patients. Six-minute walk test (6MWT) has been proposed as a simple, inexpensive, reproducible alternative to CPET. The 6MWT reproduces the activity of daily life and this is particularly relevant in elderly patients who usually develop symptoms below their theoretical maximal exercise capacity. Despite some limits 6MWT is attractive for patients referred to Departments of Internal Medicine allowing an objective evaluation of exercise tolerance, a better prognostic evaluation and a guide to evaluate response to medical treatment.

Percent predicted value for the 6-minute walk test: using norm-referenced equations to characterize severity in persons with CHF

BACKGROUND

The 6-minute walk test (6MWT) is a widely used measure of functional capacity in patients with chronic heart failure (CHF). Norm-referenced equations that predict the 6-minute walk distance (6MWD) according to age, height, weight, and gender have been proposed for healthy patients. We explored whether these equations apply to CHF patients.

METHODS AND RESULTS

The sample consisted of 213 patients newly admitted to specialized CHF clinics in Montreal, Canada. Percent predicted value (PPV) for 6MWD was calculated using norm-referenced equations. We explored correlations between different measures: PPV, 6MWD, Minnesota Living with Heart Failure Quality of Life score (MLHF-QOL). We compared severity among different age, gender, and BMI (body mass index) subgroups and assessed consistency using different measures of severity. Mean age was 65.5 years and 77.5% were men. Compared with the 6MWD, PPV had a slightly better correlation with MLHF-QOL score (-0.26 versus -0.20), and slightly more predictive power in linear regressions (adjusted r(2) = 6.5% versus 4.2%). When PPV was used to differentiate severity between different age, gender, and BMI subgroups, it consistently led to similar conclusions as the MLHF-QOL score, unlike 6MWD.

CONCLUSION

The 6MWD in meters may give misleading results when used as an indicator of severity of CHF condition to compare groups with different sex, age, and BMI distributions. It may be necessary to standardize it using norm-referenced equations.

Exercise and the heart failure patient: aerobic vs strength training--is there a need for both?

Heart failure (HF) is characterized by general muscular weakness, muscle atrophy, and exercise intolerance that lead to reductions in functional capacity, ability to perform activities of daily living, and health-related quality of life. Until recently, exercise programs for patients with HF were centered on aerobic exercise training alone. Although many activities of daily living require significant muscle strength, the role of strength training for HF patients, either alone or in combination with aerobic exercise, has not been well studied. There is suggestive evidence that combined strength-aerobic exercise training may offer additional benefits in terms of health-related quality of life and functional capacity. Strength training can be targeted to reduce muscle atrophy to a greater extent than aerobic training. Further research is required to isolate the specific role of strength training regarding improvements in prognosis, HF-related morbidity and hospitalization, and health-related quality of life for patients with HF.

Comparison of the Sit-to-Stand Test with 6 min walk test in patients with chronic obstructive pulmonary disease

OBJECTIVE

To discuss the utility of Sit-to-Stand Test (STST) compared to the 6min walking test (6MWT) for the evaluation of functional status in patients with chronic obstructive pulmonary disease (COPD).

MATERIAL-METHOD

SUBJECTS

Fifty-three patients with stable COPD (mean forced expiratory volume in 1s (FEV(1)) 46+/-9% predicted, mean age 71+/-12 year) and 15 healthy individuals (mean FEV(1) 101+/-13% predicted and mean age 63+/-8) were included.

INTERVENTIONS

Functional performance was evaluated by STST and 6MWT. During the tests, severity of dyspnea (by Modified Borg Scale), heart rate, pulsed oxygen saturation (SpO(2), by Modified Borg Scale) (by pulse oxymeter), blood pressure were measured. The pulmonary function (by spirometry), quadriceps femoris muscle strength (by manual muscle test) and quality of life (by Nottingham Health Profile Survey) were evaluated.

RESULTS

The STST and 6MWT results were lower in COPD group than the healthy group (P<0.05). During the 6MWT the rise in the heart rate, systolic blood pressure and the decrease in SpO(2) were statistically significant according to STST in COPD groups (P<0.05). The STST and 6MWT were strongly correlated with each other in both groups (P<0.05). Similarly, they were correlated with age, quality of life, peripheral muscle strength and dyspnea severity in COPD groups (P<0.05).

CONCLUSION

Similar to 6MWT, STST is also able to determine the functional state correctly. Additionally, it produces less hemodynamical stress compared to the 6MWT. In conclusion, STST can be used as an alternative of the 6MWT in patients with COPD.

T cell responses are better correlates of vaccine protection in the elderly

It is commonly held that increased risk of influenza in the elderly is due to a decline in the Ab response to influenza vaccination. This study prospectively evaluated the relationship between the development of influenza illness, and serum Ab titers and ex vivo cellular immune responses to influenza vaccination in community dwelling older adults including those with congestive heart failure (CHF). Adults age 60 years and older (90 subjects), and 10 healthy young adult controls received the 2003-04 trivalent inactivated influenza vaccine. Laboratory diagnosed influenza (LDI) was documented in 9 of 90 older adults. Pre- and postvaccination Ab titers did not distinguish between subjects who would subsequently develop influenza illness (LDI subjects) and those who would not (non-LDI subjects). In contrast, PBMC restimulated ex vivo with live influenza virus preparations showed statistically significant differences between LDI and non-LDI subjects. The mean IFN-gamma:IL-10 ratio in influenza A/H3N2-stimulated PBMC was 10-fold lower in LDI vs non-LDI subjects. Pre-and postvaccination granzyme B levels were significantly lower in CHF subjects with LDI compared with subjects without LDI. In non-CHF subjects with LDI, granzyme B levels increased to high levels at the time of influenza infection. In conclusion, measures of the ex vivo cellular immune response to influenza are correlated with protection against influenza while serum Ab responses may be limited as a sole measure of vaccine efficacy in older people. Ex vivo measures of the cell-mediated immune response should be incorporated into evaluation of new vaccines for older adults.

Functional Status in Rate- Versus Rhythm-Control Strategies for Atrial Fibrillation

OBJECTIVES

The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) functional status substudy aimed to test the hypothesis that functional status is similar in rate-control and rhythm-control strategies.

BACKGROUND

Randomized studies, including the AFFIRM study, have failed to demonstrate survival benefits between rate-control and rhythm-control strategies for atrial fibrillation (AF). However, AF may cause functional capacity or cognitive impairment that might justify maintenance of sinus rhythm.

METHODS

Investigators of the AFFIRM study enrolled 4,060 patients with AF who required long-term therapy and who were 65 years of age or older or who had another risk factor for stroke or death. New York Heart Association functional class (NYHA-FC) and Canadian Cardiovascular Society Angina Classification were assessed at initial and each follow-up visit. From 22 randomly chosen functional status substudy sites, 245 participants underwent 6-min walk tests and Mini-Mental State Examination (MMSE) at initial, two-month, and yearly visits. Patients were assigned randomly to rate-controlling drugs, allowing AF to persist, or rhythm-controlling antiarrhythmic drugs, to maintain sinus rhythm.

RESULTS

The NYHA-FC worsened with time in both rate-control and rhythm-control groups, with no differences between groups. Presence of AF was associated with worse NYHA-FC (p < 0.0001). No differences were observed in Canadian Cardiovascular Society Angina Classification or MMSE scores. Six-minute walk distance improved over time in both study arms. On average, walk distance was 94 feet greater in the rhythm-control group (adjusted p = 0.049).

CONCLUSIONS

Modest improvement in 6-min walk distance was noted in the rhythm-control arm. Presence of AF was associated with worse NYHA-FC. No difference in cognitive function was detected.

Anabolic growth hormone action improves submaximal measures of physical performance in patients with HIV-associated wasting

Growth hormone (GH) treatment reverses the muscle loss allegedly responsible for diminished aerobic capacity and increased fatigue in patients with HIV-associated wasting. This study examined whether submaximal measures of physical performance can be used as objective measures of the functional impact of GH treatment-induced anabolism. We randomized 27 HIV-positive men [mean (SD) age, 43.9 (7.2) yr; body mass, 71.9 (10.4) kg; BMI, 23.1 (2.8) kg/m2] with unintentional weight loss despite antiretroviral therapy to receive GH (6 mg) or placebo in a double-blinded, placebo-controlled, cross-over trial with a 3-mo washout. Lean body mass (LBM), maximum oxygen uptake (Vo2 peak), ventilatory threshold (VeT), 6-min walk test (6MWT) distance and work, profile of mood states (POMS) fatigue and vigor scores, and Nottingham health profile (NHP) energy and physical mobility scores were measured. LBM significantly increased after 3 mo of GH treatment vs. placebo (means +/- SE, 3.7 +/- 0.6 vs. 0.3 +/- 0.4 kg; P < 0.001). VeT significantly improved (17.6 +/- 3.7 vs. -5.9 +/- 2.5%; P < 0.001), but Vo2 peak did not change significantly. 6MWT distance improved (24.9 +/- 9.7 vs. 19.9 +/- 11.6 m; P > 0.05) and 6MWT work increased significantly more after 3 mo of GH treatment (33.3 +/- 8.8 vs. 16.5 +/- 7.5 kJ; P < 0.05). POMS scores of fatigue and vigor and the NHP score of energy improved, yet the changes were not statistically significant. GH treatment improved VeT linearly to the increase in LBM (r =0.43, P = 0.037) and 6MWT work (r = 0.51, P = 0.008), and the increase in 6MWT work correlated with increase in LBM (r = 0.45, P = 0.024). Improvement in 6MWT work above the median (27.3 kJ) showed a decrease in fatigue (r = -0.62, P = 0.024). We concluded that GH treatment-induced LBM gains in HIV-associated wasting were functionally relevant, as determined by effort-independent submaximal measures of cardiopulmonary exercise testing.

Predictors of exercise capacity and everyday activity in older heart failure patients

BACKGROUND

Exercise capacity and daily activity are key outcomes for older, frail heart failure patients. Little is known about the determinants of these outcomes in this patient group.

AIMS

To explore predictors of exercise capacity and daily activity in older, frail heart failure patients.

METHODS

Analysis of prospectively collected data from a cohort of 82 patients aged 70 years and over, enrolled in a randomised controlled trial of exercise in heart failure patients. Pathophysiological, demographic, psychological and social factors were analysed by multivariate regression to determine predictors of exercise capacity (6-min walk distance) and daily activity (daily accelerometer counts).

RESULTS

Between 49% and 55% of the variance in 6-min walk distance was explained by variables including New York Heart Association class, depression score, attitude to ageing and use of walking aids. Only 11% to 26% of the variance in accelerometer scores was explained by the model; 6-min walk distance was the only consistent predictor of daily activity.

CONCLUSIONS

Physical, psychological and attitudinal variables contribute to variance of the 6-min walk. Six-minute walk distance predicts a small amount of the variance in daily activity, but the majority of variance in daily activity remains unexplained and requires further investigation.

Effect of congestive heart failure on humoral and ex vivo cellular immune responses to influenza vaccination in older adults

This study examined the effect of congestive heart failure (CHF) on immune responses to influenza vaccination (2000-2001 preparation) in three groups of older adults including healthy, Class II and Class III/IV CHF. Serum antibody titers measured by hemagglutination inhibition (HI), and interferon-gamma (IFN-gamma), interleukin-10 (IL-10) and granzyme B (GrzB) levels in ex vivo virus-activated mononuclear cell cultures showed significant responses from pre-vaccination to 4 and 12 weeks post-vaccination (P<0.01). There was a trend for lower GrzB and higher IFN-gamma and IL-10 levels in healthy versus CHF groups (P<0.06) for all viral strains at 4 weeks. HI titers did not differ between groups. In the regression model, Grz B levels were significantly predicted by the IFN-gamma:IL-10 ratio and performance on the 6 min Walk Test; age and CHF dropped out of the model. In conclusion, CHF in older adults predicts GrzB responses to influenza vaccination due to cytokine and physical ability differences.