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Leslie I Katzel

Publications and source records attributed to Leslie I Katzel.

15 recordsLinked to original sources
PubMed2007

Reduction in midthigh low-density muscle with aerobic exercise training and weight loss impacts glucose tolerance in older men.

CONTEXT: Intramuscular lipid content increases with aging and obesity and is directly related to impaired glucose tolerance and insulin resistance. OBJECTIVE: Our purpose was to determine the effects of aerobic exercise training (AEX) with and without weight loss (WL) on midthigh low-density muscle (LDM; a measure of im lipid) and whether changes in LDM impact glucose tolerance in sedentary older men. DESIGN: Forty-six men (60.4 +/- 1.1 yr) completed 6 months of AEX (n = 34) or AEX + WL (n = 12) and had oral glucose tolerance tests (OGTTs) and computed tomography measures of LDM and regional abdominal and thigh fat depot areas. RESULTS: At baseline, LDM area directly correlated with fasting plasma glucose (FPG), 120-min glucose (G(120)), and glucose area under the curve (G(AUC)) during an OGTT (r = 0.44, r = 0.51, and r = 0.54, respectively, P < 0.01). After the interventions, the AEX + WL group had greater decreases in LDM (-13.5 vs. +1.3%, respectively), FPG (-8.3 vs. +2.1%, respectively), G(120) (-22.5 vs. -3.6%, respectively), and G(AUC) (-17.3 vs. - 3.1%, respectively) than the AEX group. In the entire sample, the decreases in LDM correlated with reductions in FPG, G(120), and G(AUC) during an OGTT (r = 0.31, r = 0.34, and r = 0.41, P < 0.05). Changes in other regional fat depots did not independently correlate with glucose tolerance or insulin responses. CONCLUSION: AEX + WL is more efficacious than AEX for reducing LDM and glucose tolerance. The improvement in glucose tolerance may be partially mediated by decreases in LDM in older men.

Blood Glucose↗
PubMed2006

Association of comorbidity with physical disability in older HIV-infected adults.

Comorbidity, aging, and their impact on physical functioning will play an increasingly greater role in HIV medical care as the number of infected adults over 50 years of age grows. The study objective was to investigate the relationship of comorbidity and age with physical functioning in HIV-infected and HIV-negative patients. Eight hundred eighty-nine HIV-infected veterans and 647 HIV-negative veterans from the Veterans Aging Cohort Study conducted between September 2001 and June 2002 were included in the study. Physical functioning was measured by self-reported difficulty with various physical activities. Regression analyses were performed to examine demographic and clinical factors associated with physical functioning. Separate models were used for HIV-infected and HIV negative subjects since these groups differed in demographic makeup. In both patient groups, chronic lung disease, coronary artery disease, hypertension, smoking, and major depression were independently associated with reduced physical functioning in age and race adjusted regression models. Increased age was associated with reduced physical functioning in both HIV-infected and HIV-negative patients. However, when comorbid conditions were entered into the models for both HIV-infected and HIV-negative patients, age coefficients were reduced and were no longer statistically significant. Among the HIV-infected patients, results remained unchanged after controlling for the impact of antiretroviral therapy and HIV disease stage. Our findings demonstrate the important role of general medical comorbidity in physical functioning in both HIV-infected and HIV-negative patients. This suggests the importance of effectively treating comorbid conditions in persons with HIV, in order to reduce the overall impact of disease on physical functioning.

Adult↗
PubMed2005

Treadmill exercise rehabilitation improves ambulatory function and cardiovascular fitness in patients with chronic stroke: a randomized, controlled trial.

BACKGROUND AND PURPOSE: Physical inactivity propagates disability after stroke through physical deconditioning and learned nonuse. We investigated whether treadmill aerobic training (T-AEX) is more effective than conventional rehabilitation to improve ambulatory function and cardiovascular fitness in patients with chronic stroke. METHODS: Sixty-one adults with chronic hemiparetic gait after ischemic stroke (>6 months) were randomized to 6 months (3x/week) progressive T-AEX or a reference rehabilitation program of stretching plus low-intensity walking (R-CONTROL). Peak exercise capacity (Vo2 peak), o2 consumption during submaximal effort walking (economy of gait), timed walks, Walking Impairment Questionnaire (WIQ), and Rivermead Mobility Index (RMI) were measured before and after 3 and 6 months of training. RESULTS: Twenty-five patients completed T-AEX and 20 completed R-CONTROL. Only T-AEX increased cardiovascular fitness (17% versus 3%, delta% T-AEX versus R-CONTROL, P<0.005). Group-by-time analyses revealed T-AEX improved ambulatory performance on 6-minute walks (30% versus 11%, P<0.02) and mobility function indexed by WIQ distance scores (56% versus 12%, P<0.05). In the T-AEX group, increasing training velocity predicted improved Vo2 peak (r=0.43, P<0.05), but not walking function. In contrast, increasing training session duration predicted improved 6-minute walk (r=0.41, P<0.05), but not fitness gains. CONCLUSIONS: T-AEX improves both functional mobility and cardiovascular fitness in patients with chronic stroke and is more effective than reference rehabilitation common to conventional care. Specific characteristics of training may determine the nature of exercise-mediated adaptations.

Aged↗
PubMed2005

Stress-induced blood pressure reactivity and cognitive function.

OBJECTIVE: To examine the relation of stress-induced blood pressure (BP) reactivity to cognitive function. METHODS: Ninety-four healthy stroke- and dementia-free middle-aged and older adults (ages 54 to 79; 62% male; 90% white) completed biomedical, psychophysiological, and neuropsychological assessment procedures. RESULTS: After statistical adjustment for age, education, state anxiety, fasting glucose levels, and resting systolic or diastolic BP (depending on the model), greater systolic BP reactivity was associated with decreased performance on Logical Memory-Immediate Recall (r2 = 0.08; p < 0.007), Logical Memory-Delayed Recall (r2 = 0.06; p < 0.02), and Stroop interference scores (r2 = 0.04; p < 0.05). Enhanced diastolic BP reactivity was similarly associated with decreased performance on Logical Memory-Immediate Recall (r2 = 0.06; p < 0.02) and Stroop interference scores (r2 = 0.06; p < 0.02). CONCLUSIONS: Independent of resting clinic blood pressure (BP), systolic and diastolic BP reactivity was associated with diminished performance on tests of immediate and delayed verbal memory and executive function (i.e., response inhibition), accounting for 3 to 8% of the variance in these measures.

Age Factors↗
PubMed2005

Relationship between objective measures of peripheral arterial disease severity to self-reported quality of life in older adults with intermittent claudication.

OBJECTIVES: The aim of this study was to determine the relation between functional measures of peripheral arterial disease (PAD) severity with both disease-specific and generic self-reported health-related quality-of-life (HR-QOL) measures, as well as the relation between the two types of HR-QOL measures. METHODS: This was a cross-sectional observation of participants from the community and primary care or vascular surgery clinics in an academic Veterans Administration medical center. Eighty patients with symptomatic Fontaine stage II PAD provided physiologic measures and self-response questionnaires. Objective measures included the ankle-brachial index (ABI), time to maximum claudication pain on a graded exercise test, and a 6-minute floor-walking distance. Self-reports included the Walking Impairment Questionnaire (WIQ), a disease-specific HR-QOL measure and the Medical Outcomes Study (MOS) Short-Form 36 (SF-36), a generic HR-QOL measure. RESULTS: Patients (mean age 70 +/- 8 [+/- SD] and 85% men) exhibited moderate-to-severe PAD by objective measures of ABI (0.65 +/- 0.19) and time in minutes to maximal claudication on a graded exercise test (7:54 +/- 4:58). Significant correlations were found between these measures and the WIQ distance, MOS-Physical Function, and MOS-Role Limitations due to physical dysfunction. The SF-36 and the WIQ subscales were significantly correlated. CONCLUSION: In older PAD patients with intermittent claudication, objective measures of disease severity are correlated with a self-reported, disease-specific and generic HR-QOL.

Aged↗
PubMed2005

The effect of exercise intensity on the response to exercise rehabilitation in patients with intermittent claudication.

PURPOSE: The purpose of this randomized trial was to compare the efficacy of a low-intensity exercise rehabilitation program vs a high-intensity program in changing physical function, peripheral circulation, and health-related quality of life in peripheral arterial disease (PAD) patients limited by intermittent claudication. METHODS: Thirty-one patients randomized to low-intensity exercise rehabilitation and 33 patients randomized to high-intensity exercise rehabilitation completed the study. The 6-month exercise rehabilitation programs consisted of intermittent treadmill walking to near maximal claudication pain 3 days per week at either 40% (low-intensity group) or 80% (high-intensity group) of maximal exercise capacity. Total work performed in the two training regimens was similar by having the patients in the low-intensity group exercise for a longer duration than patients in the high-intensity group. Measurements of physical function, peripheral circulation, and health-related quality of life were obtained on each patient before and after the rehabilitation programs. RESULTS: After the exercise rehabilitation programs, patients in the two groups had similar improvements in these measures. Initial claudication distance increased by 109% in the low-intensity group (P < .01) and by 109% in the high-intensity group (P < .01), and absolute claudication distance increased by 61% (P < 0.01) and 63% (P < .01) in the low-intensity and high-intensity groups, respectively. Furthermore, both exercise programs elicited improvements (P < .05) in peak oxygen uptake, ischemic window, and health-related quality of life. CONCLUSION: The efficacy of low-intensity exercise rehabilitation is similar to high-intensity rehabilitation in improving markers of functional independence in PAD patients limited by intermittent claudication, provided that a few additional minutes of walking is accomplished to elicit a similar volume of exercise.

Aged↗
PubMed2005

Diagnosis of hypertension and high blood pressure levels negatively affect cognitive function in older adults.

BACKGROUND: Hypertension is associated with diminished performance on tests of cognitive function. The degree to which those diagnosed with hypertension have controlled blood pressure (BP) levels may be a critical determinant of cognitive outcomes. Persons with hypertension and poorly controlled BP are likely to display the worst performance on cognitive tests. PURPOSE: The purpose is to examine potential interactive relations of hypertension diagnostic status and current BP levels to cognitive function. METHODS: Participants were 101 healthy older adults (ages 53-84, 62% male, 90% White, 29% diagnosed with hypertension) who engaged in biomedical and neuropsychological assessment. RESULTS: After statistical adjustment for age and education, persons with high BP performed more poorly than those with normal BP on the Visual Reproductions-Immediate and Delayed Recall and the Grooved Pegboard tests. Diagnosed hypertension was related to poorer performance on the Grooved Pegboard tests. An interaction of diagnosed hypertension and BP level revealed that those diagnosed with hypertension and also having poorly controlled BP levels performed least well on the Grooved Pegboard tests and the Trail Making Test-Part A. CONCLUSION: Irrespective of prior diagnostic status, individuals with high BP displayed compromised performance on tests of nonverbal memory, motor speed, and manual dexterity. However, as compared to the other groups, those diagnosed with hypertension and also having poorly controlled BP elevation were most vulnerable to difficulties on tests of perceptuo-motor speed, motor speed, and manual dexterity. These findings suggest the need for increased attention to preventative efforts with respect to BP assessment and control in older adults to help preserve cognitive function.

Aged↗
PubMed2004

Stress-induced blood pressure reactivity and silent cerebrovascular disease.

BACKGROUND AND PURPOSE: Exaggerated blood pressure (BP) responses to mental stress, an index of autonomic dysregulation, have been related to enhanced risk for stroke. This study examined cross-sectional relations of stress-induced BP reactivity to silent cerebrovascular disease assessed by magnetic resonance imaging (MRI) in healthy older adults. METHODS: Sixty-seven nondemented, community-dwelling older adults (ages 55 to 81; 75% male) free of major medical, neurological, or psychiatric disease, engaged in: (1) clinical assessment of resting systolic and diastolic BP; (2) assessment of systolic and diastolic BP responses to 3 laboratory-based mental stressors; and (3) MRI. MRIs were rated for small silent infarcts (> or =3 mm), infarct-like lesions (<3 mm), and periventricular and deep white matter hyperintensities (WMH). RESULTS: After adjustment for age, gender, resting clinic BP, and fasting glucose levels, higher systolic BP reactivity was associated with an increased number of small silent infarcts (r2=0.14; P=0.004) and greater severity ratings of periventricular (r2=0.08; P<0.04) and deep WMH (r2=0.06; P<0.05). Higher diastolic BP reactivity was similarly associated with an increased number of small silent infarcts (r2=0.08; P<0.04), and greater severity ratings of periventricular (r2=0.08; P<0.04) and deep WMH (r2=0.11; P=0.009). CONCLUSIONS: These results indicate that greater stress-induced BP reactivity is associated with enhanced silent cerebrovascular disease on MRI in healthy asymptomatic older adults independent of resting BP levels. Exaggerated stress-induced BP reactivity warrants further examination as a potential biobehavioral risk factor for cerebrovascular disease.

Aged↗
PubMed2004

Response to exercise rehabilitation in smoking and nonsmoking patients with intermittent claudication.

BACKGROUND: The purpose was to compare the changes in claudication pain, ambulatory function, daily physical activity, peripheral circulation, and health-related quality of life following a program of exercise rehabilitation in smoking and nonsmoking patients with peripheral arterial disease (PAD) limited by intermittent claudication. Methods and results Thirty-nine smokers (63 +/- 4 pack-year smoking history; mean +/- SE) and 46 nonsmokers (former smokers who had a 51 +/- 7 pack-year smoking history who quit 14 +/- 2 years prior to investigation) completed the study. The 6-month exercise rehabilitation program consisted of intermittent treadmill walking to near maximal claudication pain 3 days per week, with progressive increases in walking duration and intensity during the program. Measurements were obtained on each patient before and after rehabilitation. Following exercise rehabilitation the smokers and nonsmokers had similar improvements in these measures, as initial claudication distance increased by 119% in the smokers (P <.001) and by 97% in the nonsmokers (P <.001), and absolute claudication distance increased by 82% (P <.001) and 59% (P <.001) in the smokers and nonsmokers, respectively. Furthermore, exercise rehabilitation improved (P <.05) ambulatory function, daily physical activity, peripheral circulation, and health-related quality of life in the smokers and nonsmokers. CONCLUSION: Exercise rehabilitation is an effective therapy to improve functional independence in both smoking and nonsmoking patients with PAD limited by intermittent claudication. Therefore, smokers with intermittent claudication are prime candidates for exercise rehabilitation because their relatively low baseline physical function does not impair their ability to regain lost functional independence to levels similar to nonsmoking patients with PAD.

Aged↗
PubMed2004

Gender differences in the relation of hypertension to cognitive function in older adults.

Here we examined potential interactive relations of hypertension and gender to cognitive function in 98 healthy, older adults (ages 55-83 years; 64% male; 92% White). After statistical adjustment for age and education, hypertensives performed significantly more poorly than normotensives on tests of motor speed and manual dexterity (p < 0.05). The adverse consequences of hypertension in older adults was more pronounced for female than male hypertensives on tests of delayed visual memory, visual attention and working memory, visuoconstructional ability, motor speed and manual dexterity for the non-dominant hand (p < 0.05); these are dimensions of performance for which female gender may be a relative disadvantage. The findings suggest the need to further examine subgroups that are vulnerable to the cognitive correlates of hypertension. The results also highlight the need for increased attention to blood pressure control in older adults for the preservation of cognitive function.

Aged↗
PubMed2003

Cerebral blood flow and anxiety in older men: an analysis of resting anterior asymmetry and prefrontal regions.

Asymmetric resting blood flow in prefrontal and hemispheric regions, assessed by single photon emission computed tomography (SPECT), was examined as a potential biological marker for enhanced trait and state anxiety in 30 older men (ages 55-81). Average and asymmetric perfusion in dorsolateral, medial, and orbital regions of the prefrontal lobes was also assessed. Results indicated a significant association between lower levels of resting dorsolateral blood flow and greater state anxiety responses to a series of stressful provocations (measured on a separate occasion). A significant curvilinear (U-shaped) relation between asymmetric dorsolateral perfusion and state anxiety was also identified; increased asymmetric blood flow favoring either the right or the left dorsolateral region related to higher levels of state anxiety. However, this association was attenuated by age and systolic blood pressure. Resting perfusion in the dorsolateral region may represent a more reliable biological marker for state anxiety than trait anxiety in older men.

Aged↗
PubMed2002

Sleep-disordered breathing and insulin resistance in middle-aged and overweight men.

Sleep-disordered breathing is a prevalent condition associated with impairment of daytime function and may predispose individuals to metabolic abnormalities independent of obesity. The primary objective of this study was to determine the metabolic consequences and community prevalence of sleep-disordered breathing in mildly obese, but otherwise healthy, individuals. One hundred and fifty healthy men, without diabetes or cardiopulmonary disease, were recruited from the community. Measurements included polysomnography, a multiple sleep latency test, an oral glucose tolerance test, determination of body fat by hydrodensitometry, and fasting insulin and lipids. The prevalence of sleep-disordered breathing, depending on the apnea-hypopnea index (AHI) cutoff, ranged from 40 to 60%. After adjusting for body mass index (BMI) and percent body fat, an AHI gt-or-equal, slanted 5 events/h was associated with an increased risk of having impaired or diabetic glucose tolerance (odds ratio, 2.15; 95% CI, 1.05-4.38). The impairment in glucose tolerance was related to the severity of oxygen desaturation (DeltaSa(O(2))) associated with sleep-disordered breathing. For a 4% decrease in oxygen saturation, the associated odds ratio for worsening glucose tolerance was 1.99 (95% CI, 1.11 to 3.56) after adjusting for percent body fat, BMI, and AHI. Multivariable linear regression analyses revealed that increasing AHI was associated with worsening insulin resistance independent of obesity. Thus, sleep-disordered breathing is a prevalent condition in mildly obese men and is independently associated with glucose intolerance and insulin resistance.

Adult↗
PubMedDate not supplied

Effects of long-term exercise rehabilitation on claudication distances in patients with peripheral arterial disease: a randomized controlled trial.

PURPOSE: To determine if improvements in physical function and peripheral circulation after 6 months of exercise rehabilitation could be sustained over a subsequent 12-month maintenance exercise program in older patients with intermittent claudication. METHODS: Seventeen patients randomized to exercise rehabilitation and 14 patients randomized to usual care control completed this 18-month study. Patients exercised three times per week during the first 6 months of a progressive exercise program, followed by two times per week during the final 12 months of a maintenance program. Patients were studied at baseline, 6 months, and 18 months during the study. RESULTS: Eighteen months of exercise rehabilitation increased the initial claudication distance by 373 meters (189%) (P <.001), the absolute claudication distance by 358 meters (80%) (P <.001), walking economy by 11% (P <.001), 6-minute walk distance by 10% (P <.001), daily physical activity by 31%, and maximal calf blood flow by 18% (P <.001). These changes were similar to those found after 6 months of exercise rehabilitation (P = NS), and were significantly greater than the changes in the control group throughout the study (P <.05). CONCLUSION: Improvements in claudication distances, walking economy, 6-minute walk distance, physical activity level, and peripheral circulation after 6 months of exercise rehabilitation are sustained for an additional 12 months in older patients with intermittent claudication using a less frequent exercise maintenance program.

Aged↗
PubMedDate not supplied

Peripheral arterial disease and cognitive function.

OBJECTIVE: Peripheral arterial disease (PAD) is associated with comorbid atherosclerosis of the coronary and carotid arteries and is a significant risk factor for stroke. However, cognitive function in PAD patients before clinically evident stroke remains poorly characterized. Here we hypothesized that, on neuropsychological testing, PAD patients would perform more poorly than healthy control subjects, and persons with mild cardiovascular disease (essential hypertension), but better than stroke patients, thus reflecting a continuum of cognitive impairment associated with increased severity of vascular disease. METHOD: The cognitive performance of 38 PAD patients (mean ankle-brachial index=0.67, Fontaine Class II) was contrasted with that of 23 healthy normotensive controls, 20 essential hypertensives, and 26 anterior ischemic stroke patients on twelve neuropsychological tests. RESULTS: PAD patients performed significantly more poorly than hypertensives and normotensives, but better than stroke patients, on seven tests of nonverbal memory, concentration, executive function, perceptuo-motor speed, and manual dexterity. Hypertensives displayed poorer performance than normotensives on tests of nonverbal memory and manual dexterity. These findings were independent of age, education, and depression scores. Higher diastolic blood pressure and plasma glucose levels predicted poorer performance of select cognitive tests by PAD patients. Eight to 67% of PAD patients displayed impaired performance (< 5(th) percentile of normotensive controls) on the seven aforementioned cognitive tests. CONCLUSIONS: PAD patients exhibit diminished performance across a variety of domains of cognitive function. Findings also suggest a continuum of cognitive impairment associated with increasingly severe manifestations of cardiovascular disease, thus emphasizing the need for enhanced preventative measures to avert functional declines.

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