Naohiko Osada

Effect of the self-monitoring approach on exercise maintenance during cardiac rehabilitation: a randomized, controlled trial.

Izawa KP, Watanabe S, Omiya K, Hirano Y, Oka K, Osada N, Iijima S: Effect of the self-monitoring approach on exercise maintenance during cardiac rehabilitation: A randomized, controlled trial. Am J Phys Med Rehabil 2005;84:313–321. Objective:To evaluate the effect of the self-monitoring approach (SMA) on self-efficacy for physical activity (SEPA), exercise maintenance, and objective physical activity level over a 6-mo period after a supervised 6-mo cardiac rehabilitation (CR) program. Design:We conducted a randomized, controlled trial with 45 myocardial infarction patients (38 men, seven women; mean age, 64.2 yrs) recruited after completion of an acute-phase, exercise-based CR program. Patients were randomly assigned to an SMA group (n = 24) or control group (n = 21). Along with CR, the subjects in the SMA group self-monitored their weight and physical activity for 6 mos. The SMA used in this study was based on Bandura’s self-efficacy theory and was designed to enhance confidence for exercise maintenance. The control group participated in CR only. All patients were evaluated with the SEPA assessment tool. Exercise maintenance, SEPA scores, and objective physical activity (average steps per week) as a caloric expenditure were assessed at baseline and during a 6-mo period after the supervised CR program. Results:Mean period from myocardial infarction onset did not differ significantly between the SMA and control groups (12.1 ± 1.3 vs. 12.2 ± 1.2 mos, P = 0.692). All patients maintained their exercise routine in the SMA group. Mean SEPA score (90.5 vs. 72.7 points, P < 0.001) and mean objective physical activity (10,458.7 vs. 6922.5 steps/wk, P < 0.001) at 12 mos after myocardial infarction onset were significantly higher in the SMA than control group. SEPA showed significant positive correlation with objective physical activity (r = 0.642, P < 0.001). Conclusions:SMA during supervised CR may effectively increase exercise maintenance, SEPA, and objective physical activity at 12 mos after myocardial infarction onset.

Long-term exercise maintenance, physical activity, and health-related quality of life after cardiac rehabilitation

Izawa KP, Yamada S, Oka K, Watanabe S, Omiya K, Iijima S, Hirano Y, Kobayashi T, Kasahara Y, Samejima H, Osada N: Long-term exercise maintenance, physical activity, and health-related quality of life after cardiac rehabilitation. Am J Phys Med Rehabil 2004;83:884–892. Objective:The purpose of this study was to determine exercise maintenance rate, leisure-time objective physical activity level, and health-related quality of life in relation to exercise maintenance over the 6-mo period after a supervised 5-mo recovery-phase cardiac rehabilitation program in acute myocardial infarction patients. The study also investigated whether exercise maintenance resulted in reproducible health-related quality-of-life outcomes comparable with those of the Japanese normal population. Design:This observational study comprised 109 acute myocardial infarction patients (89 men, 20 women; mean age, 63.5 ± 10.1 yrs). Physiologic outcomes (peak oxygen uptake, handgrip, and knee-extension strength) measured at 1 and 6 mos after acute myocardial infarction onset were compared. Completed exercise maintenance and health-related quality-of-life questionnaires and results of electronic pedometer recordings to evaluate leisure-time objective physical activity level were assessed 6 mos after cardiac rehabilitation. Results:The mean period from acute myocardial infarction to evaluation of outcomes was 18.8 ± 3.4 mos. Ninety of 109 patients (82.6%) continued exercise for >6 mos after cardiac rehabilitation (exercise group); 19 patients (17.4%) quit exercise after cardiac rehabilitation (nonexercise group). Improvement in physiologic outcomes was noted at 6 mos vs. those at 1 mo, but outcomes were not significantly different between groups. The exercise group performed significantly better than the nonexercise group for leisure-time objective physical activity level and scored significantly higher than the nonexercise group for seven of eight health-related quality of life measures, attaining scores similar to those of the Japanese normal population. Conclusions:At >18 mos after acute myocardial infarction, the exercise maintenance rate in our patients remains high, and exercise maintenance may be one of the factors contributing to improvement of health-related quality of life and leisure-time objective physical activity level.

Handgrip strength as a predictor of prognosis in Japanese patients with congestive heart failure.

Background Whether upper-extremity and lower-extremity muscle strength can predict a prognosis of congestive heart failure (CHF) patients is unclear. This study evaluated the impact of muscle strength on long-term mortality in patients with CHF. Design Prospective observational study of male Japanese CHF patients. Methods Clinical characteristics (age, body mass index, left ventricular ejection fraction, heart failure etiology, and medications) were obtained from hospital records of 148 male outpatients with stable CHF. Brain natriuretic peptide was determined as an index of disease severity. Peak oxygen uptake ( V . O 2 ), handgrip, and knee extensor muscle strength were also determined. Results After 1331.9 ± 700.3 days of follow-up, 13 cardiovascular-related deaths occurred, and the patients were divided into two groups: survival (n = 135) and nonsurvival (n = 13). No significant differences were found between the groups in clinical characteristics, brain natriuretic peptide levels, and knee extensor muscle strength. Peak ( V . O 2 ) (P = 0.011) and handgrip strength (P = 0.008) were significantly lower in the nonsurvival versus survival group. Left ventricular ejection fraction, peak ( V . O 2 ), and handgrip strength were found by univariate Cox proportional hazards analysis to be significant prognostic indexes of survival. Multivariate analysis, however, revealed handgrip strength to be an independent predictor of prognosis. A handgrip strength cutoff value of 32.2 kgf was determined by the analysis of receiver-operating characteristics and was assessed. Kaplan-Meier survival curves after log-rank test showed significant prognostic difference between the two groups (P = 0.008). Conclusion Handgrip strength may be useful for forecasting prognosis in patients with CHF. Eur J Cardiovasc Prev Rehabil 16:21-27

Muscle strength in relation to disease severity in patients with congestive heart failure.

Izawa KP, Watanabe S, Yokoyama H, Hiraki K, Morio Y, Oka K, Osada N, Omiya K: Muscle strength in relation to disease severity in patients with congestive heart failure. Am J Phys Med Rehabil 2007;86:893–900. Objective:Indices of exercise capacity such as peak oxygen uptake (&OV0312;O2peak) and muscle strength are important in association with reduced mortality. The present study compared differences in &OV0312;O2peak and muscle strength indices (grip strength and knee extensor and flexor muscle strength) with disease severity and investigated the relation of these variables in congestive heart failure (CHF) patients. Design:The study comprised 102 patients with stable CHF (93 men, age 61.4 ± 10.2 yrs) with left ventricular ejection fraction (LVEF) <40% by echocardiography. We used New York Heart Association (NYHA) functional class to index disease severity. &OV0312;O2peak, grip strength, knee extensor, and flexor muscle strength were determined. Patients were divided into three groups by NYHA class: class I (n = 39), class II (n = 49), and class III (n = 14). Results:Age, sex, and LVEF did not differ according to NYHA class. &OV0312;O2peak and all muscle strength indices decreased with increases in NYHA class (P < 0.05). &OV0312;O2peak correlated positively with all muscle strengths (P < 0.05). Stepwise linear regression analysis revealed that grip and knee extensor strength were important in predicting &OV0312;O2peak. Conclusions:Exercise capacity and disease severity in CHF patients may be influenced not only by lower-limb but also upper-limb muscle strength.

Three-dimensional echocardiographic assessments of exercise-induced changes in left ventricular shape and dyssynchrony in patients with dynamic functional mitral regurgitation

AIMS Left ventricular (LV) shape and LV dyssynchrony are two cofactors associated with functional mitral regurgitation (MR) in patients with heart failure. Both can be accurately examined by real-time three-dimensional echocardiography (3DE). We examined the relationship between dynamic MR and exercise-induced changes in LV shape and synchronicity using 3DE. METHODS AND RESULTS Fifty patients with systolic LV dysfunction underwent 2D and 3D quantitative assessment of LV function, shape, and synchronicity at rest and during symptom-limited exercise test. According to the magnitude of change in MR, patients were divided into EMR group (15 patients, 30%), if the degree of MR increased during test, and NEMR group. During exercise, the changes in LV volumes and ejection fraction were similar in both groups, whereas changes in mitral valvular deformation parameters, in LV sphericity index, and in the extent of LV dyssynchrony were more pronounced in the EMR group. At rest, only the 3D sphericity index could distinguish the two groups. By stepwise multiple regression model, dynamic changes in the systolic dyssynchrony index, sphericity index, and coaptation distance were associated with dynamic MR (r(2) = 0.45, P = 0.012). CONCLUSION Dynamic MR during exercise is related to the 3D changes in LV shape and in LV synchronicity.

Changes in mitral regurgitation and left ventricular geometry during exercise affect exercise capacity in patients with systolic heart failure.

AIMS exercise may dramatically change the extent of functional mitral regurgitation (MR) and left ventricular (LV) geometry in patients with chronic heart failure (CHF). We hypothesized that dynamic changes in MR and LV geometry would affect exercise capacity. METHODS AND RESULTS this study included 30 CHF patients with functional MR who underwent symptom-limited bicycle exercise stress echocardiography and cardiopulmonary exercise testing for quantitative assessment of MR (effective regurgitant orifice; ERO), and pulmonary artery systolic pressure (PASP). LV sphericity index was obtained from real-time three-dimensional echocardiograms. The patients were stratified into exercised-induced MR (EMR; n = 10, an increase in ERO by ≥13 mm(2)) or non-EMR (NEMR; n = 20, an increase in ERO by <13 mm(2)) group. At rest, no differences in LV volume and function, ERO, and PASP were found between the two groups. At peak exercise, PASP and sphericity index were significantly greater (all P < 0.01) in the EMR group. The EMR group revealed lower peak oxygen uptake (peak VO(2); P = 0.018) and greater minute ventilation/carbon dioxide production slope (VE/VCO(2) slope; P = 0.042) than the NEMR group. Peak VO(2) negatively correlated with changes in ERO (r = -0.628) and LV sphericity index (r = -0.437); meanwhile, VE/VCO(2) slope was well correlated with these changes (r = 0.414 and 0.364, respectively). A multivariate analysis identified that the change in ERO was the strongest predictor of peak VO(2) (P = 0.001). CONCLUSION dynamic changes in MR and LV geometry contributed to the limitation of exercise capacity in patients with CHF.

The exercise training effects of skeletal muscle strength and muscle volume to improve functional capacity in patients with myocardial infarction

BACKGROUND No previous studies have fully investigated the exercise training effect on the skeletal muscle strength and volume to improve the exercise capacity in patients with myocardial infarction (MI). The present study was performed based on a hypothesis that the relationship between exercise capacity, skeletal muscle strength and volume might be changed by the amount of skeletal muscle volume in MI patients up to 3 months after the onset. METHODS Seventy patients with MI underwent symptom-limited cardiopulmonary exercise testing using a treadmill. The lower limb muscle volume (MV) was evaluated according to electrical impedance analysis and the maximal knee extension strength (Peak torque: PT) was measured by a Biodex. All patients participated in 12-week exercise training program. The subjects were divided into 2 groups on the basis of MV: Group H, MV>==22 kg; Group L, MV<22 kg. Delta values were calculated as follows: the value at 3 months minus the value at 1 month. RESULTS A positive and significant correlation was observed between the delta PT and delta peak VO(2) (r=0.50, p<0.005) only in the L group. No significant correlation was observed between the delta peak VO(2) and the delta lower limb MV or between the delta lower limb MV and the delta PT in the 2 groups. CONCLUSIONS Cardiac rehabilitation program combined with resistance and aerobic training improved exercise capacity and increased not the skeletal muscle volume but the skeletal muscle strength in patients with MI in their recovery phase. It was presumed that the improvement of exercise capacity was determined by the skeletal muscle strength not by the muscle volume especially in MI patients with low muscle volume.

Age-related differences in physiologic and psychosocial outcomes after cardiac rehabilitation.

Izawa KP, Watanabe S, Oka K, Hiraki K, Morio Y, Kasahara Y, Osada N, Omiya K, Iijima S: Age-related differences in physiologic and psychosocial outcomes after cardiac rehabilitation. Objective:To examine differences in physiologic and psychosocial outcomes between age groups after an exercise-based supervised-recovery phase II cardiac rehabilitation outpatient program. Design:This is a longitudinal observational study. The study assessed 442 consecutive cardiac patients. Patients were divided into the middle-aged group (<65 yrs, n = 242) and older-age group (≥65 yrs, n = 200). Peak oxygen uptake, handgrip and knee extensor muscle strength, upper- and lower-body self-efficacy for physical activity, and physical component summary and mental component summary scores as assessed by SF-36 were measured at 1 and 3 mos after the onset of acute myocardial infarction or cardiac surgery and were compared. Results:All physiologic and psychosocial outcomes increased significantly between months 1 and 3 in both groups. However, increases were greater in the middle-aged vs. older-aged group in peak oxygen uptake (+13.1% vs. +8.7%, P < 0.01), knee extensor muscle strength (+17.6% vs. +13.3%, P = 0.01), lower-body self-efficacy for physical activity (+17.3% vs. +12.7%, P = 0.02), and physical component summary score (+5.4% vs. +2.7%, P = 0.02). Conclusions:Age-related differences in various physiologic and psychosocial measures indicated greater improvement from an exercise-based supervised recovery-phase II cardiac rehabilitation outpatient program in middle-aged vs. older-aged patients. Older adults may derive equal mental or emotional benefit from such a cardiac rehabilitation program but do not experience as much improvement in physiologic outcomes as middle-aged adults.

The relation between Geriatric Nutritional Risk Index and muscle mass, muscle strength, and exercise capacity in chronic heart failure patients.

a Graduate School of Health Sciences, Kobe University, Kobe, Japan b Department of Rehabilitation Medicine, St. Marianna University School of Medicine Hospital, Kawasaki, Japan c Department of Physical Therapy, Tokushima Bunri University, Tokushima, Japan d Faculty of Sport Sciences, Waseda University, Tokorozawa, Japan e Division of Cardiology, St. Marianna University Toyoko Hospital, Kawasaki, Japan f Department of Cardiology, St. Marianna University Yokohama City Seibu Hospital, Yokohama, Japan g Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC, USA h Department of Orthopedic Surgery, St. Marianna University School of Medicine, Kawasaki, Japan i Division of Cardiology, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan

Relationship between sleep apnea syndrome and sleep blood pressure in patients without hypertension.

BACKGROUND AND PURPOSE Ambulatory blood pressure monitoring (ABPM) provides an accurate assessment of blood pressure (BP) and shows non-dipper BP pattern in many sleep apnea syndrome (SAS) patients with hypertension (HTN); however, little information is available on the relationship between the severity of SAS and circadian BP changes in SAS patients without HTN. This study investigated whether SAS patients without HTN would have different BP courses in the severity of SAS. METHODS AND SUBJECTS Seventy-four consecutive outpatients without HTN [systolic BP (BPs) at clinic <140mmHg and/or diastolic BP (BPd) at clinic <90mmHg], who received no antihypertensives, underwent overnight polysomnography (PSG) and ABPM. The apnea-hypopnea index (AHI) was calculated from the PSG results; patients were stratified into the following 4 groups based on their AHI: non-SAS, mild-, moderate-, or severe-SAS. RESULTS The diurnal BPs and BPd showed no differences in the severity of SAS; however, the sleep BPs, lowest BPs, and pre-awake BPs were significantly higher in the severe-SAS group than the non-SAS group (p=0.02, p=0.04, and p=0.006, respectively). The sleep BPd and pre-awake BPd were significantly higher in the severe-SAS than the non-SAS (p=0.01 and p=0.0003, respectively) and mild-SAS (p=0.01 and p=0.008, respectively) groups. CONCLUSIONS The results of this study suggested that SAS affected nocturnal BP elevation even in SAS patients without HTN. The diurnal BP showed no difference in the severity of SAS; however, the severe-SAS group revealed significant nocturnal BP elevation.