Added Value of Physical Performance Measures in Predicting Adverse Health-Related Events: Results from the Health, Aging and Body Composition Study

OBJECTIVES: To determine how three different physical performance measures (PPMs) combine for added utility in predicting adverse health events in elders.
DESIGN: Prospective cohort study.
SETTING: Health, Aging and Body Composition Study.
PARTICIPANTS: Three thousand twenty-four well-functioning older persons (mean age 73.6).
MEASUREMENTS: Timed gait, repeated chair stands, and balance (semi- and full-tandem, and single leg stands each held for 30 seconds) tests were administered at baseline. Usual gait speed was categorized to distinguish high- and low-risk participants using the previously established 1-m/s cutpoint. The same population-percentile (21.3%) was used to identify cutpoints for the repeated chair stands (17.1 seconds) and balance (53.0 seconds) tests. Cox proportional hazard analyses were performed to evaluate the added value of PPMs in predicting mortality, hospitalization, and (severe) mobility limitation events over 6.9 years of follow-up.
RESULTS: Risk estimates for developing adverse health-related events were similarly large for each of the three high-risk groups considered separately. Having more PPM scores at the high-risk level was associated with a greater risk of developing adverse health-related events. When all three PPMs were considered, having only one poor performance was sufficient to indicate a highly significantly higher risk of (severe) lower extremity and mortality events.
CONCLUSION: Although gait speed is considered to be the most important predictor of adverse health events, these findings demonstrate that poor performance on other tests of lower extremity function are equally prognostic. This suggests that chair stand and standing balance performance may be adequate substitutes when gait speed is unavailable.     

Effect of short-term isometric handgrip training on blood pressure in middle-aged females

Objective

To determine the effect of isometric handgrip training on blood pressure (BP) in middle-aged women (47.88 ± 1.8 years).

Methods

Isometric handgrip training was performed over five consecutive days. In each session, the treatment group (n = 9) performed four isometric contractions of 45 seconds each at 30% of their maximal grip strength. The control group (n = 9) sat for 15 minutes without exercising, for five consecutive days. Resting systolic (SBP) and diastolic blood pressure (DBP) were measured pre- and post-intervention. Data were analysed using a two-factor ANOVA (p ≤ 0.05).

Results

Blood pressure readings were reduced in both groups (SBP: p = 0.036; DBP: p = 0.0079), however there was no interaction effect for SBP or DBP.

Conclusions

The findings suggest that 15 minutes of sitting per day for five consecutive days is just as effective as isometric handgrip training for reducing BP levels. Future research is required to investigate the optimal isometric handgrip training stimulus required to reduce resting BP levels.     

The influence of physical exercise and leisure activity on neuropsychological functioning in older adults

It has been suggested that leisure activity and physical exercise can be a protective factor for neuropsychological functions and are associated with a reduced risk of dementia. Thus, the purpose of this study was to investigate the influence of physical exercise and leisure on the neuropsychological functions of healthy older adults. The sample was composed of 51 sedentary female volunteers who were 60–70 years old and were distributed into three groups: A—control, B—leisure, and C—training. Volunteers were submitted to a physical and neuropsychological assessment at baseline and after 6 months. Groups A and B were monitored longitudinally three times a week. Group C improved their neuropsychological functioning and oxygen consumption compared to groups A and B (p = <0.05). The neuropsychological functions of groups A and B were significantly worse after 6 months of monitoring (p = <0.05). The data suggest that physical exercise improves neuropsychological functioning, although leisure activities may also improve this functioning. Thus, an aerobic physical fitness program can partially serve as a non-medication alternative for maintaining and improving these functions in older adults; however, leisure activities should also be considered.     

Performance Measures Predict Onset of Activity of Daily Living Difficulty in Community‐Dwelling Older Adults

OBJECTIVES: To assess the predictive value of five performance‐based measures for the onset of difficulty in activities of daily living (ADLs). DESIGN: A prospective cohort study; home visits every 6 months for 18 months. SETTING: Community‐based. PARTICIPANTS: Community‐dwelling older adults, n=110, (mean age 80.3±7.0; range 67–98) who reported no difficulty in basic ADLs. MEASUREMENTS: The Short Physical Performance Battery (SPPB), gait speed, Berg Balance Scale (BBS), grip strength, and Timed Up and Go Test (TUG) were evaluated at baseline. Seven ADL items were assessed at baseline and 6, 12, and 18 months. The onset of ADL disability was self‐report of difficulty in any of the seven ADL items. Logistic regression models were fitted for each of the physical performance measures to predict onset of ADL difficulty at 6, 12, and 18 months. RESULTS: After controlling for age, comorbid conditions, and sex, the BBS was the most consistent and best predictor for the onset of ADL difficulty over an 18‐month period (6 months, c‐statistic=0.725, (95% confidence interval (CI)=0.60–0.85; 12 months, c‐statistic=0.840 95% CI=0.75, 0.93; 18 months, c‐statistic=0.821, 95% CI=0.71, 0.93). The SPPB showed excellent predictive value for the onset of difficulty at 12 months. Ninety‐five, 89, and 75 older adults completed the 6, 12, and 18‐month follow‐up visits, respectively. CONCLUSION: BBS, followed by SPPB, TUG, gait speed, and grip strength, were predictive of the onset of ADL difficulty over an 18‐month period in community‐dwelling older adults. Screening nondisabled older adults with simple performance tests could allow clinicians to identify those at risk for ADL difficulty and may help to detect early functional decline.     

Effects of smoking and physical activity on body weight: developments in Sweden between 1980 and 1989

Abstract. Objectives . To study the effects of changes in smoking and exercise habits on body weight in Sweden. Design . Analysis of factors affecting relative body weight by construction of regression equations using two models: one adjusted for age, education, socioeconomic group, geographical region and nationality, the other further adjusted for cigarette smoking and leisure-time physical activity. Setting . Cross-sectional interview data derived from the ‘Undersökning om LevnadsFörhållanden’ (Living Conditions) survey 1980–81 and 1989–89. Subjects . Nationally representative samples of Swedish men and women aged 16–84. Main outcome measures . Changes in body-mass index (BMI) in Sweden during the 1980s. Results . Using the first model, an increase in the BMI of 0.23 kg/m² in men and 0.17 kg/m² in women, from 1980 to 1989, was found. When controlling for smoking and physical activity, these values were 0.20 and 0.18 kg/m², respectively, (P at least < 0.003). Conclusions . These findings indicate that the reported decrease in smoking and changes in physical activity during the 1980s only marginally explain the BMI increase in the adult Swedish population. The health programmes launched during the 1980s seem to have little beneficial effects on body-weight development, in particular in younger generations of both sexes.     

Physical activity as a determinant of change in mobility performance: the Longitudinal Aging Study Amsterdam

OBJECTIVES: This study examined the association of (change in) physical activity and decline in mobility performance in older men and women. DESIGN: A 3-year prospective study using data of the Longitudinal Aging Study. SETTING: Netherlands. PARTICIPANTS: Two thousand one hundred nine men and women aged 55 to 85. MEASUREMENTS: Total physical activity (expressed as hours per day and kilocalories per day) and sports participation were measured using a validated, interviewer-administered questionnaire. Mobility performance was assessed using two timed tests: 6-meter walk and repeated chair stands. RESULTS: Mobility performance declined for 45.6% of the sample. At baseline, the mean time +/- standard deviation spent on total physical activity was 3.0 +/- 2.1 h/d or 719 +/- 543 kcal/d, and 56.6% of the sample participated in sports. Sports participation and a higher level of total physical activity, walking, or household activity were associated with a smaller mobility decline. After 3 years, total physical activity declined, and only 53.4% of those reporting sports at baseline continued doing so. Continuation of physical activity over time was associated with the smallest decline in mobility. The observed associations were similar for those with and without chronic disease (P> 0.3). The conclusions did not change after adjustment for potential confounders, including demographic and lifestyle variables, depression, and cognitive status. CONCLUSIONS: Physical activity, and especially a regularly active lifestyle, may slow the decline in mobility performance. A beneficial effect was observed for sports and nonsports activities, independent of the presence of chronic disease.     

Pharmacological inhibition of TRalpha1 receptor potentiates the thyroxine effect on body weight reduction in rats: potential therapeutic implications in controlling body weight

It has been previously reported that thyroid hormone receptor alpha1 (TRalpha1) is involved in the regulation of food intake and heart rhythm. Herein, we show that pharmacological inhibition of TRalpha1 by dronedarone, an amiodarone like compound (shown to antagonize thyroid hormone binding to TRalpha1), prevented the thyroid hormone induced increase in food intake and heart rate acceleration in rats. This resulted in a marked reduction in body weight. It is likely that thyroid analogs may prove potential therapeutic agents for controlling body weight.     

Melatonin reduces body weight in goldfish (Carassius auratus): effects on metabolic resources and some feeding regulators

Abstract:  The objective of the present study was to analyze the effects of chronic melatonin (10 μg/g body weight) on body weight and the main energetic reserves, particularly hepatic and muscle content of proteins, lipids and glycogen in goldfish. In addition, we studied plasma leptin and ghrelin, and hypothalamic content of neuropeptide Y (NPY) and monoamines after chronic melatonin treatment in order to elucidate a possible interplay between melatonin and these feeding regulators on the body weight regulation in this species. Body weight gain and specific growth rate were reduced (74% and 76%, respectively) after chronic (10 days) intraperitoneal (i.p.) treatment with melatonin. The carbohydrate and lipid metabolism was regulated by melatonin in goldfish, because this indoleamine reduced muscle glycogen stores and increased lipid mobilization. A suppressive trend, but not statistically significant, in circulating ghrelin was observed after chronic treatment with melatonin. Chronic melatonin administration significantly reduced noradrenergic metabolism and increased dihydroxiphenylacetic acid content in the hypothalamus, without significant modifications in the serotoninergic system. Thus, it could be suggested that melatonin may mediate its action on energy balance in fish, at least in part, via interactions with hypothalamic catecholaminergic system. Plasma leptin and hypothalamic NPY remained unaltered after melatonin treatment, suggesting that these feeding regulators may not be involved in the effects of melatonin on energy homeostasis in fish.     

Physical activity, quality of life and symptoms of depression in community-dwelling and institutionalized older adults

This study was aimed to investigate in a sample of Spanish elderly whether measures of physical activity are related to health-related quality of life (HRQoL) and symptoms of depression in community dwelling and institutionalized elderly. The sample was a cohort of 436 elderly (234 women and 202 men, aged 60-98 years) from the North of Spain. 58% were community-dwellers and 42% were institutionalized in senior residences. Participants completed measures of physical activity (Yale Physical Activity Survey, YPAS), HRQoL (Medical Outcomes Study 36-item Short Form Health Survey, SF-36) and symptoms of depression (Geriatric Depression Scale, GDS). All SF-36 domains, except role-emotional, were significantly correlated with the YPAS activity dimension summary index. Physical function, role-physical, general health and vitality correlated with total time activity, and correlations were observed between weekly energy expenditure and physical function, role physical, vitality and mental health. Depressive symptom scores correlated significantly with the YPAS activity dimension summary index and the weekly energy expenditure. Scores for various domains of the SF-36 and for depressive symptoms significantly differed among less and more active individuals of the same sex and institutionalization category. Differences generally reached a higher extent in institutionalized subjects in comparison to community dwellers. In conclusion, physical activity was related to different domains of both the physical and mental components of HRQoL and to decreased depressive symptoms. Results emphasize the positive effects of physical activity in both community-dwelling and institutionalized older adults.     

An investigation of factors influencing self-care behaviors in young and middle-aged adults with hypertension based on a health belief model

Objectives

To explore whether five variables of the health belief model were factors influencing self-care behaviors in young and middle-aged adults with hypertension.

The effect of body weight on the induction of mild hypothermia in a rabbit model of asphyxia cardiac arrest

Objective To investigate the effect of body weight on the induction of mild hypothermia in a rabbit model of asphyxia cardiac arrest. Methods Twenty-four rabbits were randomized into two groups： the ice bag group and the intravenous 4℃ saline group. Cardiac arrest was induced and after 3 minutes of cardiac arrest, cardiopulmonary resuscitation was begun. Simultaneously, mild hypothermia was induced by putting an ice bag over the abdomen or infusion of 4℃ saline via an ear vein. A 2℃ decrease of rectal temperature was considered as the completion of hypothermia induction. Induction times were recorded, compared, and analyzed with respect to body weight. Results All rabbits had restoration of spontaneous circulation （ROSC） and ROSC lasted during the experiment. Induction time in the ice bag group was significantly shorter than that in the intravenous 4℃ saline group （22.8 ± 4.7 min VS 42.5 ± 4.0 min, P〈 0.001）. Induction time significantly correlated with body weight in the ice bag group （Pearson Correlation： r = 0.725, P = 0.029）, but not in the intravenous 4℃ saline group （Pearson Correlation： P = 0.418）. Conclusions In a rabbit model, induction of mild hypothermia with an ice bag is faster than with intravenous 4~C saline; induction time positively correlates with body weight when an ice bag is used, but not when intravenous 4℃ saline used. The effect of body weight should be considered when choosing an appropriate method to achieve early induction of mild hypothermia     

Melatonin effect on rat body weight regulation in response to high-fat diet at middle age

We previously demonstrated that daily melatonin administration to middle-aged rats to restore youthful plasma melatonin levels also decreased body weight, visceral fat, plasma leptin, and plasma insulin to more youthful levels, without detectable changes in consumption of chow diet. We now evaluate: (a) whether melatonin alters consumption of a more precisely quantifiable liquid diet similar in high-fat content to the typical American diet; (b) differences between melatonin-induced endocrine responses in the fasted vs fed state; and (c) time course of these responses. Ten-month-old male Sprague- Dawley rats received liquid diet containing either 0.2 μg/mL melatonin (MELATONIN) or vehicle (CONTROL) (n=14/treatment); the diet was available throughout each night, but was removed for the final 10 h of each daytime. MELATONIN rats gained 4% body weight during the first 2 wk and then stabilized, whereas CONTROL rats continued to gain for an additional week, achieving 8% gain (p<0.05 vs MELATONIN). During the first 3 wk, afternoon tail-blood leptin, but not insulin, levels decreased in melatonin-treated rats (p<0.05 vs CONTROL). After 8 wk, half of the rats were killed at the midpoint of the dark period (NIGHT; fed) and half at the end of the light period (DAYTIME; fasted). NIGHT but not DAYTIME plasma leptin levels were decreased in MELATONIN rats, whereas DAYTIME but not NIGHT plasma insulin levels were decreased (p<0.05 vs CONTROL). Melatonin treatment did not alter cumulative food consumption. Thus, melatonin decreased weight gain in response to high-fat diet, decreased plasma leptin levels within 3 wk—before decreasing plasma insulin—and exerted these metabolic effects independent of total food consumption.     

The effects of water-based exercise in combination with blood flow restriction on strength and functional capacity in post-menopausal women

Water-based exercise and low-intensity exercise in combination with blood flow restriction (BFR) are two methods that have independently been shown to improve muscle strength in those of advancing age. The objective of this study was to assess the long-term effect of water-based exercise in combination with BFR on maximum dynamic strength and functional capacity in post-menopausal women. Twenty-eight women underwent an 8-week water-based exercise program. The participants were randomly allocated to one of the three groups: (a) water exercise only, (b) water exercise + BFR, or (c) a non-exercise control group. Functional capacity (chair stand test, timed up and go test, gait speed, and dynamic balance) and strength testing were tested before and after the 8-week aquatic exercise program. The main findings were as follows: (1) water-based exercise in combination with BFR significantly increased the lower limb maximum strength which was not observed with water-based exercise alone and (2) water-based exercise, regardless of the application of BFR, increased functional performance measured by the timed up and go test over a control group. Although we used a healthy population in the current study, these findings may have important implications for those who may be contraindicated to using traditional resistance exercise. Future research should explore this promising modality in these clinical populations.     

The role of smoking and other modifiable lifestyle risk factors in maintaining and restoring lower body mobility in middle-aged and older Americans: results from the HRS and AHEAD. Health and Retirement Study. Asset and Health Dynamics Among the Oldest Old

OBJECTIVES: To analyze the effect of smoking, smoking cessation, and other modifiable risk factors on mobility in middle-aged and older Americans. DESIGN: Panel study; secondary data analysis. SETTING: United States (national sample). PARTICIPANTS: The Health and Retirement Study (HRS) includes data on 12,652 Americans aged 50 to 61 in four waves (1992-1998). The Asset and Health Dynamics Among the Oldest Old (AHEAD) survey followed 8,124 community-dwelling people aged 70 years and older in three waves (1993-1998). MEASUREMENTS: The relationships between the primary outcome measure, lower body mobility (ability to walk several blocks and walk up one flight of stairs without difficulty), and smoking, exercise (HRS only), body mass index (BMI), and alcohol use were estimated in bivariate and multivariate analyses. RESULTS: Not smoking was strongly positively related to mobility, and the relative effects were similar in both panels. Among those with impaired mobility at baseline, not smoking was also strongly related to recovery. In the middle aged, there were consistent dose-response relationships between amount smoked and impaired mobility. Fifteen years after quitting, the risk of impaired mobility returned to that of never smokers. There was also a strong dose-response relationship between level of exercise and mobility. Inverted U-shaped relationships with mobility were observed for BMI and alcohol consumption. CONCLUSIONS: The relationships between not smoking and lower body mobility in middle-aged and older Americans are strong and consistent. Interventions aimed at reducing smoking have the potential to preserve mobility and thereby prolong health and independence in later life.     

Dietary supplementation of tetradecylthioacetic acid increases feed intake but reduces body weight gain and adipose depot sizes in rats fed on high-fat diets

Aim: The pan-peroxisome proliferator-activated receptor (PPAR) ligand and fatty acid analogue tetradecylthioacetic acid (TTA) may reduce plasma lipids and enhance hepatic lipid metabolism, as well as reduce adipose tissue sizes in rats fed on high-fat diets. This study further explores the effects of TTA on weight gain, feed intake and adipose tissue functions in rats that are fed a high-fat diet for 7 weeks.
Methods: The effects on feed intake and body weight during 7 weeks' dietary supplement with TTA (∼200 mg/kg bw) were studied in male Wistar rats fed on a lard-based diet containing ∼40% energy from fat. Adipose tissue mass, body composition and expression of relevant genes in fat depots and liver were measured at the end of the feeding.
Results: Despite higher feed intake during the final 2 weeks of the study, rats fed on TTA gained less body weight than lard-fed rats and had markedly decreased subcutaneous, epididymal, perirenal and mesenteric adipose depots. The effects of TTA feeding with reduced body weight gain and energy efficiency (weight gain/feed intake) started between day 10 and 13. Body contents of fat, protein and water were reduced after feeding lard plus TTA, with a stronger decrease in fat relative to protein. Plasma lipids, including Non-Esterified Fatty Acids (NEFA), were significantly reduced, whereas fatty acid β-oxidation in liver and heart was enhanced in lard plus TTA-fed rats. Hepatic UCP3 was expressed ectopically both at protein and mRNA level (>1900-fold), whereas Ucp1 mRNA was increased ∼30-fold in epididymal and ∼90-fold in mesenteric fat after lard plus TTA feeding.
Conclusion: Our data support the hypothesis that TTA feeding may increase hepatic fatty acid β-oxidation, and thereby reduce the size of adipose tissues. The functional importance of ectopic hepatic UCP3 is unknown, but might be associated with enhanced energy expenditure and thus the reduced feed efficiency.     

Prognostic effect of exercise capacity on mortality in older adults with diabetes mellitus

OBJECTIVES: To investigate the prognostic effect of exercise capacity in older individuals with diabetes mellitus. DESIGN: Retrospective data review in a clinic‐based cohort. SETTING: Veterans Affairs Medical Centers in Washington, District of Columbia, and Palo Alto, California. PARTICIPANTS: Two thousand eight hundred sixty‐seven men aged 50 to 87 with type 2 diabetes mellitus. MEASUREMENTS: Exercise tolerance testing with fitness categories based on peak metabolic equivalents of task (METs) achieved adjusted for age. All‐cause mortality in age groups 50 to 65 (Group 1; n=1,658) and older than 65 (Group 2; n=1,209) was analyzed using adjusted Cox proportional hazards models. RESULTS: After a mean ± standard deviation follow‐up period of 7.8 ± 5.1 years, there were 324 deaths in Group 1 (20%) and 464 in Group 2 (38%). For each 1‐MET increase in exercise capacity, mortality was 18% lower for the entire cohort (hazard ratio (HR)=0.82, 95% confidence interval (CI)=0.79–0.86), 23% lower for Group 1 (HR=0.77, 95% CI=0.73–0.82), and 16% lower for Group 2 (HR=0.84, 95% CI=0.8–0.89). When fitness categories were considered, the mortality risk was 30% to 80% lower for those who achieved more than 4 METs in both age groups. CONCLUSION: Augmented exercise capacity is associated with lower risk of mortality in people with type 2 diabetes mellitus aged 50 to 65 as well as in those older than 65. Thus, physical fitness, as represented by exercise capacity, lowers mortality risk in people with diabetes mellitus irrespective of age. These findings suggest that healthcare providers should be cognizant of the level of exercise capacity in individual patients and encourage a physically active lifestyle regardless of age.     

Physical activity and functional fitness in institutionalized vs. independently living elderly: a comparison of 70-80-year-old city-dwellers

The purpose of the study was to compare the level of energy expenditure due to physical activity (EEPA) and functional fitness (FF) in 59 women and 82 men aged 70-80 years, divided into three groups: permanent residents in assisted-living facilities (ALFs), participants in adult day care centers (DCCs) and older people living independently, members in community senior centers (CSCs). EEPA and FF were analyzed taking into consideration sex differences. The energy expenditure tended to be lower in DCCs and ALFs subjects than in CSCs members, but significant differences were obtained only in women. Women in different living settings differed only in endurance. In men, the differences were clear in most tests (endurance, strength, agility/dynamic balance) except for flexibility. Institutionalization was connected with a significantly lower level of FF and equalization of sex differences. Education seemed to be an important factor influencing the level of FF in men.