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W L Haskell

Publications and source records attributed to W L Haskell.

189 records · Page 11Linked to original sources

The role of insulin and body fat in associations of physical activity with lipids and lipoproteins in a biethnic population. The San Luis Valley Diabetes Study.

It has been postulated that the positive effects of physical activity on high density lipoprotein cholesterol (HDL-C) and HDL-C subfraction 2 (HDL-C2) are mediated through insulin action because increased activity lowers insulin levels and lower insulin levels are associated with higher HDL-C. These relations were evaluated in a rural population of Hispanic and non-Hispanic white (NHW) adults in Colorado. Included were 138 men and 152 women with normal glucose tolerance confirmed by World Health Organization criteria. Total physical activity was assessed by 7-day recall interviews. No significant associations were observed among women. Among men, activity was inversely associated with fasting insulin (r = -0.17, p less than 0.05). From analysis of covariance models including the interaction term activity x ethnicity, total HDL-C was 43.4 mg/dl (95% confidence interval [CI] = 39.1, 47.7) in the low tertile of activity and 50.4 mg/dl (95% CI = 46.3, 54.5) in the high tertile for NHW men, after adjustment for fasting insulin, fasting glucose, body mass index (BMI), waist to hip ratio (WHR), and age. For Hispanic men, adjusted HDL-C was 43.4 mg/dl (95% CI = 38.6, 48.2) and 49.1 mg/dl (95% CI = 44.0, 54.2) in the low and high tertiles, respectively. Adjusted HDL-C2 levels were 52% higher in the most compared with the least active NHW men, whereas there was no difference by activity for Hispanic men. Higher adjusted mean levels of HDL-C3 were observed for the high compared with the low activity tertile in both ethnic groups. Ethnicity-specific models showed that for NHW men, activity explained 12% (p = 0.01), fasting insulin explained 5% (p = 0.05), and BMI explained 6% (p = 0.04) of the variability in total HDL-C, after adjustment for fasting glucose, WHR, and age. These models confirmed that effects of insulin and body fat did not explain the observed associations between activity and total HDL-C and its subfractions.

Adipose Tissue↗

Relation of fasting plasma insulin concentration to high density lipoprotein cholesterol and triglyceride concentrations in men.

Low plasma high density lipoprotein (HDL) cholesterol concentration is a risk factor for coronary heart disease (CHD) and is frequently associated with high triglyceride concentration. Both of these abnormalities have been related to insulin resistance as estimated by plasma insulin concentrations and to measures of obesity, regional adiposity, and physical fitness. To determine which of these variables (fasting plasma insulin, obesity as measured by body mass index [BMI], or regional adiposity as measured by waist to hip ratio [WHR]) best identifies men with low HDL cholesterol and high triglyceride concentrations, we divided 83 men, aged 50-65 years, who were free of CHD or diabetes, into tertiles based on BMI, WHR, or fasting plasma insulin concentration. Only for plasma insulin tertiles were there statistically significant differences in HDL cholesterol (tertile 1, mean +/- SEM, 1.34 +/- 0.08 mmol/l; 2, 1.16 +/- 0.05 mmol/l; 3, 1.10 +/- 0.06 mmol/l; p less than 0.03) and triglyceride (tertile 1, 1.05 +/- 0.08 mmol/l; 2, 1.48 +/- 0.12 mmol/l; 3, 1.82 +/- 0.17 mmol/l; p less than 0.005) concentrations. In forward stepwise regressions with HDL cholesterol and triglyceride as dependent variables, fasting insulin concentration but not BMI, WHR, or maximal oxygen uptake (VO2max), a measure of physical fitness, predicted HDL cholesterol (R2 = 0.07, p less than 0.02) and triglyceride (R2 = 0.20, p less than 0.001) concentrations. The data suggest that plasma insulin concentration is an important predictor of HDL cholesterol and triglyceride concentrations independent of BMI, WHR, or VO2max.

Aged↗

Current trends in the integration and reimbursement of complementary and alternative medicine by managed care, insurance carriers, and hospital providers.

OBJECTIVES: To assess the status of managed care and insurance coverage of complementary and alternative medicine (CAM) and the integration of such services offered by hospitals. METHODS: A literature review and information search was conducted to determine which insurers had special policies for CAM and which hospitals were offering CAM. Telephone interviews were conducted with a definitive sample of 18 insurers and a representative subsample of seven hospitals. RESULTS: A majority of the insurers interviewed offered some coverage for the following: nutrition counseling, biofeedback, psychotherapy, acupuncture, preventive medicine, chiropractic, osteopathy, and physical therapy. Twelve insurers said that market demand was their primary motivation for covering CAM. Factors determining whether insurers would offer coverage for additional therapies included potential cost-effectiveness based on consumer interest, demonstrable clinical efficacy, and state mandates. Some hospitals are also responding to consumer interest in CAM, although hospitals can only offer CAM therapies for which local, licensed practitioners are available. Among the most common obstacles listed to incorporating CAM into mainstream health care were lack of research on efficacy, economics, ignorance about CAM, provider competition and division, and lack of standards of practice. CONCLUSIONS: Consumer demand for CAM is motivating more insurers and hospitals to assess the benefits of incorporating CAM. Outcomes studies for both allopathic and CAM therapies are needed to help create a health care system based upon treatments that work, whether they are mainstream, complementary, or alternative.

Complementary Therapies↗

Current trends in the integration and reimbursement of complementary and alternative medicine by managed care organizations (MCOs) and insurance providers: 1998 update and cohort analysis.

OBJECTIVES: To assess the status of managed care and insurance coverage of complementary and alternative medicine (CAM) and the integration of such services into conventional medicine. METHODS: A literature review and information search was conducted to determine which insurers had special policies for CAM. Telephone interviews were conducted with a definitive sample of 9 out of 10 new MCOs or insurers identified in 1998 and a cohort of eight MCOs and insurers who responded both to the original survey in 1997 and again in 1998 to determine trends. RESULTS: This study constitutes the results of the second year of a 3-year ongoing survey. For 1998, 10 MCOs and insurance carriers initiated CAM coverage. Survey results are analyzed for these 10 new providers as well as the results of a cohort of eight insurers surveyed in both 1997 and 1998 to determine current trends. A majority of the insurers interviewed offer some coverage for the following: nutrition counseling, biofeedback, psychotherapy, acupuncture, preventive medicine, chiropractic, osteopathy, and physical therapy. All new MCOs and insurers said that market demand was their primary motivation for covering CAM. Factors determining whether insurers would offer coverage for additional therapies included potential cost-effectiveness, consumer interest, demonstrable clinical efficacy, and state mandates. Among the most common obstacles listed to incorporating CAM into mainstream health care were lack of research on efficacy, economics, ignorance about CAM, provider competition and division, and lack of standards of practice. CONCLUSIONS: Consumer demand for CAM is motivating more MCOs and insurance companies to assess the benefits of incorporating CAM. Outcomes studies for both conventional and CAM therapies are needed to help create a health care system based upon treatments that work, whether they are conventional, complementary, or alternative.

Cohort Studies↗

The energy expenditure index: a method to quantitate and compare walking energy expenditure for children and adolescents.

We used heart rate and walking speed to calculate an energy expenditure index (EEI), the ratio of heart rate per meter walked, for 102 normal subjects, age 6-18 years. Heart rate was measured at self-selected slow, comfortable, and fast walking speeds on the floor and on a motor-driven treadmill. At slow walking speeds (37 +/- 10 m/min) the EEI was elevated (0.71 +/- 0.32 beats/m), indicating poor economy. At comfortable speeds (70 +/- 11 m/min) the EEI values decreased to the maximum economy (0.47 +/- 0.13 beats/m). At fast speeds (101 +/- 13 m/min), the EEI increased (0.61 +/- 0.17 beats/m), indicating poor economy relative to comfortable speeds. A graph of the EEI versus walking speed provides a way to evaluate and compare energy expenditure in a clinical setting.

Adolescent↗

Energy cost of walking in normal children and in those with cerebral palsy: comparison of heart rate and oxygen uptake.

The rate of oxygen uptake can be used to assess energy expenditure during walking, but the necessary instrumentation is cumbersome, expensive, and usually unavailable in the clinical setting. Heart rate is an easily measured parameter, but its use as an index of energy expenditure in children has not been validated previously. We found that the relationship between oxygen uptake and heart rate was linear throughout a wide range of walking speeds for both children with cerebral palsy and normal children. There was no significant difference between the slope or the gamma-intercept of the lines for the two groups. These findings validate the use of heart rate as an index of energy expenditure for normal children and for children with cerebral palsy.

Adolescent↗

Physical activity and exercise to achieve health-related physical fitness components.

To improve health and fitness effectively through physical activity or exercise, we need to understand how this comes about. For many of these changes, the stimulus has been grossly defined in terms of type, intensity, duration, and frequency of exercise, but for others a dose-response relationship has not been determined. Physical activity that appears to provide the most diverse health benefits consists of dynamic, rhythmical contractions of large muscles that transport the body over distance or against gravity at a moderate intensity relative to capacity for extended periods of time during which 200 to 400 kilocalories (or 4 kilocalories per kilogram of body weight) are expended. For optimal health benefits, such activity should be performed daily or at least every other day and should be supplemented with some heavy resistance and flexibility exercises. The greatest benefits are achieved when the least active individuals become moderately active; much less benefit is apparent when the already active individual becomes extremely active. Overexertion or inappropriate exercise can produce significant health risks. Research is needed to characterize better the health-promoting features of physical activity and exercise.

Adolescent↗