Wanda H Howell

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• Howell, W., Earthman, C. P., Reid, P. M., Harper, I. T., Ravussin, E., & Howell, W. H. (0). Body cell mass repletion and improved quality of life in HIV-infected individuals receiving oxandrolone. JPEN. Journal of parenteral and enteral nutrition, 26(6).
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  The aim of this study was to measure changes in body cell mass (BCM) and quality of life in HIV-infected individuals undergoing oxandrolone therapy. Previous studies on oxandrolone have neither quantified changes in BCM using criterion methods nor quality of life using an HIV-specific instrument.
• Howell, W. (2011). Nutrition in Diabetic Wound Healing. Proceedings of the Diabetic Foot Global Conference.
• Howell, W. H. (2009). Advancing the practice of dietetic education. Topics in Clinical Nutrition, 24(3), 206-210.
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  Abstract: A valid and reliable credentialing mechanism may advance the practice of the dietetic educator. Efforts to accomplish this have been thwarted by the complex variety of roles assumed by dietetics professionals, especially dietetic educators. Research in higher education provides insight that can be useful in our pursuit of the characteristics and skill sets that define advanced-level practice in dietetic education. Particularly useful is the "meta- profession" of teaching paradigm. This reconceptualization of college teaching provides a framework from which dietetic educators can begin to define levels of practice and the core value of their professional activity. © 2009 Lippincott Williams & Wilkins, Inc.
• Earthman, C., Traughber, D., Dobratz, J., & Howell, W. (2007). Bioimpedance spectroscopy for clinical assessment of fluid distribution and Body cell mass. Nutrition in Clinical Practice, 22(4), 389-405.
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  PMID: 17644693;Abstract: Body composition assessment has been used to evaluate clinical interventions in research trials, and has the potential to improve patient care in the clinical setting. Body cell mass (BCM) is an important indicator of nutrition status; however, its measurement in the clinic has been limited. BCM can be estimated by the measurement of intracellular water (ICW). The assessment of extracellular water (ECW) is also important because many clinical populations undergo alterations in fluid distribution, particularly individuals with wasting, those receiving dialysis, and obese individuals. Bioimpedance spectroscopy (BIS) is a unique bioimpedance approach that differs in underlying basis from the more readily recognized single-frequency bioelectrical impedance analysis (SF-BIA) in that it does not require the use of statistically derived, population-specific prediction equations. It has the potential advantage of not only measuring total body water (TBW), as does SF-BIA, but also offering the unique capacity to differentiate between ECW and ICW and, thus, to provide an estimate of BCM. This literature review was conducted to compare available BIS devices to multiple dilution for measuring fluid compartments or BCM in a number of populations. Variable results regarding the ability of BIS to measure absolute volumes, as well as the observation of wide limits of variation, make BIS problematic for individual assessment in the clinic, particularly in populations with abnormal fluid distribution or body geometry. BIS has been found to be more accurate for measuring changes in fluid volumes or BCM, particularly in postsurgical and human immunodeficiency virus (HIV)-infected individuals. It is certainly possible that populationspecific adjustments may improve the accuracy of BIS for assessing individuals in the clinical setting; however, additional research and development is needed before the method can be accepted for routine clinical use. © 2007 American Society for Parenteral and Enteral Nutrition.
• Howell, W., Higgins, K. J., Reid, P. M., Going, S. B., & Howell, W. H. (2007). Validation of bioimpedance spectroscopy to assess acute changes in hydration status. Medicine and science in sports and exercise, 39(6).
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  To validate bioimpedance spectroscopy (BIS) as a field method for measuring small, acute changes in extracellular water (ECW) during a fluid fast/rehydration manipulation.
• Teitelbaum, D., Guenter, P., Howell, W. H., Kochevar, M. E., Roth, J., & Seidner, D. L. (2005). Definition of terms, style, and conventions used in A.S.P.E.N. guidelines and standards. Nutrition in Clinical Practice, 20(2), 281-285.
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  PMID: 16207664;
• Cordero-MacIntyre, Z. R., Peters, W., Libanati, C. R., España, R. C., Abila, S. O., Howell, W. H., & Lohman, T. G. (2002). Reproducibility of DXA in obese women. Journal of Clinical Densitometry, 5(1), 35-44.
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  PMID: 11940727;Abstract: Dual-energy X-ray absorptiometry (DXA) measurements were analyzed using two versions of software (Hologic V8.1a and V8.21) to compare the short- and long-term precisions of the measurements. Software V8.21 was designed by the manufacturer to better address magnification effects on estimations of soft tissue lean mass. Twenty weight-stable, obese postmenopausal Caucasian women aged 40-70 yr participated in the study. Total and regional body composition measurements were obtained at baseline and after 3 mo, using a fan beam Hologic QDR 4500A absorptiometer. For the estimation of precision, duplicate scans obtained on the same day for nine women were analyzed using both versions of the software. The correlations between duplicate scans ranged from 0.886 to 0.998 and were similar between software versions. The CVs for fat and lean weights and bone mineral content (BMC) were 1.2%, 1.1%, and 1.7%, respectively, for software V8.21 compared to 1.3%, 1.3%, and 2.1%, respectively, for V8.1a. Systematic differences were found between software versions with higher values for fat and lean weights for software version V8.21. The 3-mo, long-term reproducibility of body composition estimates from DXA was only slightly less than short-term reproducibility for both software versions (coefficient of variation [CV] range from 1.3% for BMC weight to 11.0% for arm fat). Software V8.21 yielded smaller percentage mean differences between scale and DXA-estimated weights (-2.4% and -7.2% at baseline and -2.9% and -7.6% at 3 mo, respectively) and higher fat and lean weights (49.12 and 47.1 kg and 49.6 and 44.6 kg, respectively) than V8.1a. Reproducibility of all variables was comparable between software versions.
• Earthman, C. P., Reid, P. M., Harper, I. T., Ravussin, E., & Howell, W. H. (2002). Body cell mass repletion and improved quality of life in HIV-infected individuals receiving oxandrolone. Journal of Parenteral and Enteral Nutrition, 26(6), 357-365.
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  PMID: 12405647;Abstract: Background: The aim of this study was to measure changes in body cell mass (BCM) and quality of life in HIV-infected individuals undergoing oxandrolone therapy. Previous studies on oxandrolone have neither quantified changes in BCM using criterion methods nor quality of life using an HIV-specific instrument. Methods: Twenty-five HIV-infected patients (15 with an AIDS diagnosis) on standard antiretroviral and nutrition management were studied before and an average of 18.6 weeks after the initiation of oxandrolone therapy, as prescribed by their primary care physician for the treatment of weight loss. BCM was estimated from intracellular water measured by multiple dilution. Lean soft-tissue mass (LTM) was measured by dual-energy X-ray absorptiometry. Quality of life was evaluated by the Functional Assessment of HIV Infection (FAHI) questionnaire. Results: Significant gains in body weight (2.6 ± 3.0 kg; p < .0001), BCM (3.6 ± 3.0 kg; p < .0001), and LTM (3.0 ± 2.9 kg; p < .0001) occurred over an average course of 18.6 weeks of treatment. Overall quality of life improved (p = .056) and appetite improved (p = .032), both of which were positively associated with weight gain (p = .040 and p = .022, respectively). Conclusions: This is the first study involving oxandrolone therapy in HIV infection to document changes in quality of life and BCM, the metabolically active component of lean body mass that reflects nutritional status better than other more global body composition parameters. Nutritional status and quality of life can improve in HIV-infected individuals receiving a combined therapeutic approach that includes oxandrolone.
• Rogers, D., Leonberg, B. L., Broadhurst, C. B., Conklin, M. T., Howell, W. H., Lewis, C. L., Mattes, R., Parraga, I. M., Pfeiffer, M. M., Pringle, L. W., Reidy, C., Manger-Hague, K., Mitchell, B., & Bryk, J. (2002). 2000 Commission on dietetic registration dietetics practice audit. Journal of the American Dietetic Association, 102(2), 270-292.
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  PMID: 11846126;
• Swanson, G. D., Staten, L. K., Taren, D. L., Howell, W. H., Tobar, M., Poehlman, E. T., Hill, A., Reid, P. M., & Ritenbaugh, C. (2002). The Arizona activity frequency questionnaire using doubly labeled water [2]. Medicine and Science in Sports and Exercise, 34(7), 1217-.
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  PMID: 12131267;
• Staten, L. K., Taren, D. L., Howell, W. H., Tobar, M., Poehlman, E. T., Hill, A., Reid, P. M., & Ritenbaugh, C. (2001). Validation of the Arizona activity frequency questionnaire using doubly labeled water. Medicine and Science in Sports and Exercise, 33(11), 1959-1967.
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  PMID: 11689750;Abstract: Purpose: Physical activity questionnaires (PAQs) are considered the most cost-efficient method to estimate total energy expenditure (TEE) in epidemiological studies. However, relatively few PAQs have been validated using doubly labeled water (DLW) in women or in samples with diverse ethnic backgrounds. This study was conducted to validate the Arizona Activity Frequency Questionnaire (AAFQ) for estimation of TEE and physical activity energy expenditure (PAEE) over 1 month using DLW as a reference method. Methods: Thirty-five relatively sedentary women completed the AAFQ before participating in an 8-d DLW protocol to measure TEE. TEE and PAEE were estimated from the AAFQ by calculating resting metabolic rate (RMR) using the equation of Mifflin et al. (AAFQmif), by measuring RMR using indirect calorimetry (AAFQic), and using MET conversion (AAFQmet). A predictive equation for TEE was generated. Results: The mean = SD for TEE and PAEE from DLW were 9847 ± 2555 kJ·d-1 and 5578 ± 2084 kJ·d-1, respectively. Formulas using RMR to calculate the TEE and PAEE from the AAFQ tended to underestimate TEE and PAEE, whereas those that included only weight tended to overestimate TEE and PAEE. On the basis of the Mifflin et al. equation, the AAFQ tends to underestimate PAEE by 13%. This underestimation may be explained by the low lean body mass of the sample population and by effectiveness of the METs/RMR ratio in the obese. The following predictive equation was calculated: TEE (kJ·d -1) = (86.0*average total daily METs) + (2.23 * RMRmif) - 6726. When the predictive equation is used, TEE calculated from the AAFQ is highly correlated with DLW TEE (adjusted r2 = 0.70, P < 0.001). Conclusion: The AAFQ is an effective tool too] for the prediction of TEE and PAEE in epidemiological studies.
• Cordero-MacIntyre, Z. R., Lohman, T. G., Rosen, J., Peters, W., España, R. C., Dickinson, B., Reid, P. M., Howell, W. H., & Fernandez, M. L. (2000). Weight loss is correlated with an improved lipoprotein profile in obese postmenopausal women. Journal of the American College of Nutrition, 19(2), 275-284.
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  PMID: 10763910;Abstract: Background: Changes in plasma lipid and lipoprotein distributions that occur after menopause increase the risk of cardiovascular disease in women, especially in those who are overweight. Objective: The purpose of this study was to evaluate the impact of a nine-month weight reduction program on plasma lipids, dietary intake and abdominal fat obesity. Design: A partial crossover design was used to study a weight loss treatment consisting of Phentermine hydrochloride (Fastin®, SmithKline Beecham Pharmaceuticals, Philadelphia, PA) therapy plus a low energy diet (5040 kJ/d). Forty-seven obese, postmenopausal Caucasian women (BMI of 30-38 kg/m2) were randomized into two groups, both of which received drag and diet treatment over six months. However, Group I started the intervention program three months later than Group II. Plasma total, HDL and LDL cholesterol and triacylglycerol were measured, body composition was assessed by anthropometry and dual energy x- ray absorptiometry, and food frequency records were collected at four timepoints. Results: Over nine months, women in Group II reduced body weight (14.4%), lowered plasma concentrations of LDL cholesterol (14% to 26%) and triacylglycerol (15%) and raised plasma HDL cholesterol concentration (15%). These plasma lipid changes decreased the total cholesterol/HDL cholesterol ratio from 4.3 to 3.2. All subjects decreased abdominal fat measurements and energy and cholesterol intakes, as well as percentage of energy derived from total and saturated fat during the study. Most subjects also increased dietary fiber consumption. Conclusion: Both weight loss and diet modifications are associated with an improved plasma lipid profile in obese postmenopausal women.
• Cordero-MacIntyre, Z. R., Peters, W., Libanati, C. R., España, R. C., Howell, W. H., & Lohman, T. G. (2000). Reproducibility of body measurements in very obese postmenopausal women. Annals of the New York Academy of Sciences, 904, 536-538.
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  PMID: 10865800;
• Cordero-Macintyre, Z. R., Peters, W., Libanati, C. R., España, R. C., Howell, W. H., & Lohman, T. G. (2000). Effect of a weight-reduction program on total and regional body composition in obese postmenopausal women. Annals of the New York Academy of Sciences, 904, 526-535.
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  PMID: 10865799;
• Earthman, C. P., Matthie, J. R., Reid, P. M., Harper, I. T., Ravussin, E., & Howell, W. H. (2000). A comparison of bioimpedance methods for detection of body cell mass change in HIV infection. Journal of Applied Physiology, 88(3), 944-956.
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  PMID: 10710390;Abstract: The maintenance of body cell mass (BCM) is critical for survival in human immunodeficiency virus (HIV) infection. Accuracy of bioimpedance for measuring change (Δ) in intracellular water (ICW), which defines BCM, is uncertain. To evaluate bioimpedance-estimated ΔBCM, the ICW of 21 weight- losing HIV patients was measured before and after anabolic steroid therapy by dilution (total body water by deuterium - extracellular water by bromide) and bioimpedance. Multiple-frequency modeling- and dilution-determined ΔICW did not differ. The ΔICW was predicted poorly by 50-kHz parallel reactance, 50- kHz impedance, and 200 5-kHz impedance. The ΔICW predicted by 500 - 5-kHz impedance was closer to, but statistically different from, dilution- determined ΔICW. However, the effect of random error on the measurement of systematic error in the 500 5-kHz method was 12-13% of the average measured ΔICW; this was nearly twice the percent difference between obtained and threshold statistics. Although the 500 - 5-kHz method cannot be fully rejected, these results support the conclusion that only the multiple- frequency modeling approach accurately monitors ΔBCM in HIV infection.
• Chernoff, R., Bruner, D., Fitz, P., Gannon, J., Glade, M., Hansman, P., Howell, W. H., Jensen, G., Stallings, V., Wallach, S., & Zeisel, S. (1997). Credentials available in human clinical nutrition: a report of the Intersociety Committee on Nutrition Certification.. Journal of the American College of Nutrition, 16(2), 184-188.
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  PMID: 9100221;
• Chernoff, R., Bruner, D., Fitz, P., Gannon, J., Glade, M., Hausman, P., Howell, W. H., Jensen, G., Stallings, V., Wallach, S., & Zeisel, S. (1997). Credentials available in human clinical nutrition: A report of the Intersociety Committee on Nutrition Certification. American Journal of Clinical Nutrition, 65(5), 1562-1566.
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  PMID: 9157790;
• Howell, W. H., McNamara, D. J., Tosca, M. A., Smith, B. T., & Gaines, J. A. (1997). Plasma lipid and lipoprotein responses to dietary fat and cholesterol: A meta-analysis. American Journal of Clinical Nutrition, 65(6), 1747-1764.
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  PMID: 9174470;Abstract: Quantitative relations between dietary fat and cholesterol and plasma lipid concentrations have been the subject of much study and some controversy during the past 40 y. Previous meta-analysis have focused on the most tightly controlled, highest-quality experiments. To test whether the findings of these investigations are generalizable to broader experimental settings and to the design of practical dietary education interventions. Data from 224 published studies on 8143 subjects in 366 independent groups including 878 diet-blood lipid comparisons were subjected to weighted multiple-regression analysis. Inclusion criteria specified intervention studies published in English between 1966 and 1994 reporting quantitative data on changes in dietary cholesterol and fat and corresponding changes in serum cholesterol, triacylglycerol, and lipoprotein cholesterol concentrations. Regression models are reported for serum total cholesterol, triacylglycerol, and low- density-, high-density-, and very-low-density-lipoprotein cholesterol, with multiple correlations of 0.74, 0.65, 0.41, 0.14, and 0.34, respectively. Interactions of dietary factors, initial dietary intakes and serum concentrations, and study and subject characteristics had little effect on these models. Predictions indicated that compliance with current dietary recommendations (30% of energy from fat, < 10% from saturated fat, and < 300 mg cholesterol/d) will reduce plasma total and low-density-lipoprotein- cholesterol concentrations by ≃5% compared with amounts associated with the average American diet.
• Mcnamara, D. J., & Howell, W. H. (1992). Epidemiologic data linking diet to hyperlipidemia and arteriosclerosis. Seminars in Liver Disease, 12(4), 347-355.
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  PMID: 1334574;Abstract: There is little debate that an elevated plasma cholesterol level, specifically an elevated plasma LDL cholesterol level, increases cardiovascular disease risk.2,4 Data from inter- and intrapopulation studies have clearly demonstrated that as total and LDL cholesterol levels increase, cardiovascular disease risk increases. Although this relationship is generally accepted, the specifics of the relationship generate debate. Relevant questions pertain to the actual level of plasma cholesterol at which cardiovascular disease risk is increased, whether the relationship holds true across all age groups and both sexes, and what contributions plasma HDL levels and the plasma LDL/HDL ratio make to cardiovascular disease risk independent of plasma LDL levels. Irrespective of these uncertainties, the evidence that elevated plasma LDL cholesterol levels constitute an independent risk factor for cardiovascular disease has been a major component in studying the genetic and environmental factors involved in hypercholesterolemia. Epidemiologic data reveal relationships between a number of dietary elements and elevated plasma cholesterol levels with the strongest relationships between dietary fatty acids, plasma cholesterol levels, and cardiovascular disease incidence. The data from a variety of epidemiologic investigations, both cross-cultural and cross-sectional, indicate that plasma total cholesterol levels are increased by saturated fat intake and obesity. HDL cholesterol levels are decreased by intakes of low-tat, high-carbohydrate diets, a high BMI, and lack of activity and increased by intake of dietary fat, alcohol, and physical activity. Controlled clinical trials have provided verification of these epidemiologic observations in practically every case. Based on the available data, it can be predicted that for every 1% decrease in saturated fat calories and 1% increase in carbohydrate calories, plasma total cholesterol levels will decrease 1.7 mg/dl (0.8%) and HDL cholesterol levels will fall 0.3 mg/dl (0.7%). In contrast, for every 1 kg/m2 decrease in the BMI (a weight loss of approximately 3 kg), total cholesterol levels will decrease 2.8 mg/dl (1.3%) and HDL levels will increase 0.6 mg/dl (1.3%). There have been numerous dietary recommendations provided to the public as part of a population based coronary heart disease risk reduction program,9-12 and in general they have a similar message: reduce total and saturated fat intake to 30% of calories, reduce dietary cholesterol intake, maintain ideal body weight, and exercise. Finally, studies of genetic variations and polymorphisms in the apolipoproteins, the enzymes involved in the intravascular processing of the lipoproteins, and the lipoprotein receptors are essential in order to define the metabolic heterogeneity of the plasma lipoprotein responses to dietary factors. Studies of how various patterns of metabolic responses relate to the role of dietary factors in coronary heart disease risk and to the efficacy of dietary interventions in reducing cardiovascular disease risk in different subgroups of the population are also crucial.80-83 The genetic heterogeneity within populations no doubt contributes to the difficulties in defining the effects of various dietary factors on plasma lipoprotein levels and cardiovascular disease incidence within those populations. It also possibly accounts for the relatively small percentage of the variances in plasma cholesterol levels that can be attributed to the dietary variables observed in many epidemiologic studies.24 What conclusions can one draw from the large amount of epidemiologic data available relating diet, hyperlipidemia, and arteriosclerosis? First, it is important to note that the data from epidemiologic studies do not provide evidence to justify excluding any food items from the diet; no studies document good foods or bad foods relative to plasma cholesterol levels or coronary heart disease risk. Second, the conclusions that can be drawn from the data are fairly straightforward and very logical: eat a variety of foods in moderation, which will result in a dietary pattern relatively low in saturated fat and high in complex carbohydrates and fiber, maintain a healthy relative body weight by balancing caloric intake with caloric expenditure, sustain a level of physical active consistent with good health,84 and enjoy a glass or two of wine with meals.