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  1. Article ; Online: Synthesis and characterization of noble metal/metal oxide nanoparticles and their potential antidiabetic effect on biochemical parameters and wound healing

    Elobeid Mai A. / Awad Manal A. / Virk Promy / Ortashi Khalid M. / Merghani Nada M. / Asiri Atheer M. / Bashir Emadeldin Abdeljabar Ali

    Green Processing and Synthesis, Vol 11, Iss 1, Pp 106-

    2022  Volume 115

    Abstract: The study assessed the antidiabetic effect of Solenostemma argel and its nanoformulations with silver/gold nanocomposites (CNPs), zinc oxide nanoparticles (ZnONPs), and metaformin drug. Experimental groups consisted of normal control, diabetic control, ... ...

    Abstract The study assessed the antidiabetic effect of Solenostemma argel and its nanoformulations with silver/gold nanocomposites (CNPs), zinc oxide nanoparticles (ZnONPs), and metaformin drug. Experimental groups consisted of normal control, diabetic control, and four diabetic groups treated with metformin, CNPs, ZnONPs, and bulk argel leaf extract (So-argel). Transmission electron microscopy characterization showed that the synthesized CNPs and ZnONPs were of variable sizes and dimensions and were quasi-spherical in shape. Particle sizes measured by dynamic light scattering were 106 and 139 nm for CNPs and ZnONPs, respectively. Also, the polydispersity index values were 0.473 and 0.269 for CNPs and ZnONPs, respectively. The biochemical parameters were as follows: the group treated with bulk So-argel (105.00 ± 4.041 mg·dL−1) and CNPs (109.00 ± 8.373 mg·dL−1) showed a more profound anti-hyperglycemic effect and were comparable to the control (88.40 ± 2.249). Liver and kidney functions (p ≤ 0.05) improved with So-argel and its nanoformulations compared to metformin. However, bulk argel (170.33 ± 20.431 and 38.00 ± 3.05 U·L−1) and the nanocomposite (228.33 ± 11.464 and 48.00 ± 5.291 U·L−1) were efficacious in lowering serum levels of liver enzymes (AST and ALT, respectively). No significant difference was observed between urea levels. Nevertheless, bulk So-argel (0.26 ± 0.007) and CNPs (0.24 ± 0.018) were more effective than ZnONPs (0.41 ± 0.289) on serum creatinine. Nanotreatment exhibited a reduction in lesions size/healing. Overall, nanoparticles may offer a safe potential for Type 2 diabetes management.
    Keywords a diabetic lesion ; diabetes mellitus ; nanoparticles ; solenostemma argel ; Chemistry ; QD1-999
    Subject code 571
    Language English
    Publishing date 2022-01-01T00:00:00Z
    Publisher De Gruyter
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Putative environmental-endocrine disruptors and obesity: a review.

    Elobeid, Mai A / Allison, David B

    Current opinion in endocrinology, diabetes, and obesity

    2008  Volume 15, Issue 5, Page(s) 403–408

    Abstract: Purpose of review: There has been a substantial increase in the prevalence of obesity in the last several decades. Recent evidence suggests that endocrine-disrupting chemicals, for example halogenated aromatic hydrocarbons, may cause perturbations in ... ...

    Abstract Purpose of review: There has been a substantial increase in the prevalence of obesity in the last several decades. Recent evidence suggests that endocrine-disrupting chemicals, for example halogenated aromatic hydrocarbons, may cause perturbations in endogenous hormonal regulation and alter other mechanisms involved in weight homeostasis, which may lead to weight gain by increased volume of adipose tissue. Synthetic chemicals derived from industrial processes are suspected to play a contributory role. Yet of the approximately 70,000 documented synthetic chemicals, few have been examined to determine their effects on the endocrine system.
    Recent findings: The present study examines prior laboratory, epidemiological and experimental research findings. Data demonstrate migration of endocrine disruptors in the environment and are beginning to catalogue their effects on adiposity. We present postulated relationships between these chemicals, their mechanisms of action, and the obesity epidemic.
    Summary: Endocrine disruptors may adversely impact human and environmental health by altering the physiological control mechanism. Obesity, which is known to increase medical costs and reduce quality and length of life, may be increasing as a function of endocrine disruptor exposure. This merits concern among scientists and public health officials and warrants additional vigorous research in this area.
    MeSH term(s) Animals ; Endocrine Disruptors/adverse effects ; Endocrine Disruptors/chemistry ; Environmental Exposure/adverse effects ; Environmental Pollutants/adverse effects ; Hormones ; Humans ; Obesity/epidemiology ; Obesity/etiology
    Chemical Substances Endocrine Disruptors ; Environmental Pollutants ; Hormones
    Language English
    Publishing date 2008-09-04
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Review
    ZDB-ID 2272017-0
    ISSN 1752-2978 ; 1752-296X
    ISSN (online) 1752-2978
    ISSN 1752-296X
    DOI 10.1097/MED.0b013e32830ce95c
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Endocrine disruptors and obesity: an examination of selected persistent organic pollutants in the NHANES 1999-2002 data.

    Elobeid, Mai A / Padilla, Miguel A / Brock, David W / Ruden, Douglas M / Allison, David B

    International journal of environmental research and public health

    2010  Volume 7, Issue 7, Page(s) 2988–3005

    Abstract: Recent evidence suggests that endocrine disrupting chemicals (EDCs) may cause perturbations in endogenous hormonal regulation that predispose to weight gain. Using data from NHANES (1999-2002), we investigated the association between body mass index (BMI) ...

    Abstract Recent evidence suggests that endocrine disrupting chemicals (EDCs) may cause perturbations in endogenous hormonal regulation that predispose to weight gain. Using data from NHANES (1999-2002), we investigated the association between body mass index (BMI), waist circumference (WC) and selected persistent organic pollutants (POPs) via multiple linear regressions. Consistent interaction was found between gender, ln oxychlordane and ln p,p' DDT. Also, we found an association between WC and ln oxychlordane and ln hpcdd in subjects with detectable levels of POPs, whereas an association between WC and ln p,p' DDT was observed in all subjects. Furthermore, ln Ocdd showed an increase with higher WC and BMI, whereas, ln trans-nonachlor decreased with higher BMI. Hence, BMI and WC are associated with POPs levels, making the chemicals plausible contributors to the obesity epidemic.
    MeSH term(s) Adolescent ; Adult ; Body Mass Index ; Child ; Cross-Sectional Studies ; Dioxins/adverse effects ; Endocrine Disruptors/adverse effects ; Female ; Humans ; Hydrocarbons, Chlorinated/adverse effects ; Male ; Nutrition Surveys ; Obesity/etiology ; Public Health ; Regression Analysis ; United States ; Waist-Hip Ratio ; Young Adult
    Chemical Substances Dioxins ; Endocrine Disruptors ; Hydrocarbons, Chlorinated
    Language English
    Publishing date 2010-07-23
    Publishing country Switzerland
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2175195-X
    ISSN 1660-4601 ; 1661-7827
    ISSN (online) 1660-4601
    ISSN 1661-7827
    DOI 10.3390/ijerph7072988
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Bisphenol A induces hepatotoxicity through oxidative stress in rat model.

    Hassan, Zeinab K / Elobeid, Mai A / Virk, Promy / Omer, Sawsan A / ElAmin, Maha / Daghestani, Maha H / AlOlayan, Ebtisam M

    Oxidative medicine and cellular longevity

    2012  Volume 2012, Page(s) 194829

    Abstract: Reactive oxygen species (ROS) are cytotoxic agents that lead to significant oxidative damage. Bisphenol A (BPA) is a contaminant with increasing exposure to it and exerts both toxic and estrogenic effects on mammalian cells. Due to limited information ... ...

    Abstract Reactive oxygen species (ROS) are cytotoxic agents that lead to significant oxidative damage. Bisphenol A (BPA) is a contaminant with increasing exposure to it and exerts both toxic and estrogenic effects on mammalian cells. Due to limited information concerning the effect of BPA on liver, this study investigates whether BPA causes hepatotoxicity by induction of oxidative stress in liver. Rats were divided into five groups: The first four groups, BPA (0.1, 1, 10, 50 mg/kg/day) were administrated orally to rats for four weeks. The fifth group was taken water with vehicle. The final body weights in the 0.1 mg group showed a significant decrease compared to control group. Significant decreased levels of reduced glutathione, superoxide dismutase, glutathione peroxidase, glutathione-S-transferase, glutathione reductase and catalase activity were found in the 50 mg BPA group compared to control groups. High dose of BPA (50 mg/kg) significantly increased the biochemical levels of ALT, ALP and total bilirubin. BPA effect on the activity of antioxidant genes was confirmed by real time PCR in which the expression levels of these genes in liver tissue were significantly decrease compared to control. Data from this study demonstrate that BPA generate ROS and reduce the antioxidant gene expression that causes hepatotoxicity.
    MeSH term(s) Animals ; Benzhydryl Compounds ; Bilirubin/metabolism ; Biomarkers/metabolism ; Body Weight/drug effects ; Disease Models, Animal ; Gene Expression Regulation, Enzymologic/drug effects ; Liver/drug effects ; Liver/enzymology ; Liver/pathology ; Liver Diseases/enzymology ; Liver Diseases/genetics ; Liver Diseases/pathology ; Male ; Nitrosation/drug effects ; Organ Size/drug effects ; Oxidative Stress/drug effects ; Phenols/toxicity ; Rats ; Rats, Wistar
    Chemical Substances Benzhydryl Compounds ; Biomarkers ; Phenols ; bisphenol A (MLT3645I99) ; Bilirubin (RFM9X3LJ49)
    Language English
    Publishing date 2012-07-24
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2455981-7
    ISSN 1942-0994 ; 1942-0994
    ISSN (online) 1942-0994
    ISSN 1942-0994
    DOI 10.1155/2012/194829
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Waist Circumference Values Are Increasing Beyond Those Expected From BMI Increases

    Elobeid, Mai A / Desmond, Renee A / Thomas, Olivia / Keith, Scott W / Allison, David B

    Obesity research. 2007 Oct., v. 15, no. 10

    2007  

    Abstract: OBJECTIVE: The objective of this investigation was to examine the relationship between BMI and waist circumference (WC) by gender and race subgroups from U.S. population-based data from 1959 to 2004 and to investigate the trend in WC over calendar time. ... ...

    Abstract OBJECTIVE: The objective of this investigation was to examine the relationship between BMI and waist circumference (WC) by gender and race subgroups from U.S. population-based data from 1959 to 2004 and to investigate the trend in WC over calendar time. RESEARCH METHODS AND PROCEDURES: Demographic and anthropometric cross-sectional data on 30,730 participants 18 to 79 years old across five national surveys were included. We regressed WC on BMI while controlling for age in each time period for blacks and whites by gender. RESULTS: The relationship between BMI and WC as characterized by the slope of the linear regression of WC on BMI does not seem to be changing significantly over time. A small (range, 0.08 to 0.27 cm/yr) increase in WC over time was observed. DISCUSSION: The implications of these findings for public health and for understanding any extant changes in the BMI-mortality rate relationship remain to be elucidated.
    Keywords adults ; temporal variation ; waist circumference ; body mass index ; men ; women ; gender differences ; ethnic differences ; demography ; age ; Blacks ; Whites ; public health ; United States
    Language English
    Dates of publication 2007-10
    Size p. 2380-2383.
    Publishing place The North American Association for the Study of Obesity
    Document type Article
    ZDB-ID 1201744-9
    ISSN 1550-8528 ; 1071-7323
    ISSN (online) 1550-8528
    ISSN 1071-7323
    Database NAL-Catalogue (AGRICOLA)

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  6. Article: Waist circumference values are increasing beyond those expected from BMI increases.

    Elobeid, Mai A / Desmond, Renee A / Thomas, Olivia / Keith, Scott W / Allison, David B

    Obesity (Silver Spring, Md.)

    2007  Volume 15, Issue 10, Page(s) 2380–2383

    Abstract: Objective: The objective of this investigation was to examine the relationship between BMI and waist circumference (WC) by gender and race subgroups from U.S. population-based data from 1959 to 2004 and to investigate the trend in WC over calendar time.! ...

    Abstract Objective: The objective of this investigation was to examine the relationship between BMI and waist circumference (WC) by gender and race subgroups from U.S. population-based data from 1959 to 2004 and to investigate the trend in WC over calendar time.
    Research methods and procedures: Demographic and anthropometric cross-sectional data on 30,730 participants 18 to 79 years old across five national surveys were included. We regressed WC on BMI while controlling for age in each time period for blacks and whites by gender.
    Results: The relationship between BMI and WC as characterized by the slope of the linear regression of WC on BMI does not seem to be changing significantly over time. A small (range, 0.08 to 0.27 cm/yr) increase in WC over time was observed.
    Discussion: The implications of these findings for public health and for understanding any extant changes in the BMI-mortality rate relationship remain to be elucidated.
    MeSH term(s) Adolescent ; Adult ; Age Factors ; Aged ; Body Mass Index ; Female ; Humans ; Male ; Middle Aged ; Sex Factors ; Waist-Hip Ratio
    Language English
    Publishing date 2007-10-09
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2230457-5
    ISSN 1930-739X ; 1930-7381 ; 1071-7323
    ISSN (online) 1930-739X
    ISSN 1930-7381 ; 1071-7323
    DOI 10.1038/oby.2007.282
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Olive oil oleuropein has anti-breast cancer properties with higher efficiency on ER-negative cells.

    Elamin, Maha H / Daghestani, Maha H / Omer, Sawsan A / Elobeid, Mai A / Virk, Promy / Al-Olayan, Ebtesam M / Hassan, Zeinab K / Mohammed, Osama B / Aboussekhra, Abdelilah

    Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association

    2013  Volume 53, Page(s) 310–316

    Abstract: Breast cancer constitutes a major health problem for women worldwide. However, its incidence varies between populations and geographical locations. These variations could be diet-related, since there are several carcinogenic compounds in the modern diet, ...

    Abstract Breast cancer constitutes a major health problem for women worldwide. However, its incidence varies between populations and geographical locations. These variations could be diet-related, since there are several carcinogenic compounds in the modern diet, while natural products contain various anti-cancer elements. Several lines of evidence indicate that, in addition to their clear preventive effect, these compounds could also be used as therapeutic agents. In the present report we have shown that oleuropein, a pharmacologically safe natural product of olive leaf, has potent anti-breast cancer properties. Indeed, oleuropein exhibits specific cytotoxicity against breast cancer cells, with higher effect on the basal-like MDA-MB-231 cells than on the luminal MCF-7 cells. This effect is mediated through the induction of apoptosis via the mitochondrial pathway. Moreover, oleuropein inhibits cell proliferation by delaying the cell cycle at S phase and up-regulated the cyclin-dependent inhibitor p21. Furthermore, oleuropein inhibited the anti-apoptosis and pro-proliferation protein NF-κB and its main oncogenic target cyclin D1. This inhibition could explain the great effect of oleuropein on cell proliferation and cell death of breast cancer cells. Therefore, oleuropein warrants further investigations to prove its utility in preventing/treating breast cancer, especially the less-responsive basal-like type.
    MeSH term(s) Antineoplastic Agents/pharmacology ; Apoptosis/drug effects ; Breast Neoplasms/drug therapy ; Cell Cycle ; Cell Proliferation/drug effects ; Cyclin D1/metabolism ; Cyclin-Dependent Kinase Inhibitor p21/genetics ; Cyclin-Dependent Kinase Inhibitor p21/metabolism ; Electrophoresis, Polyacrylamide Gel ; Female ; Flow Cytometry ; Humans ; Iridoids ; MCF-7 Cells ; Mitochondria/metabolism ; NF-kappa B/genetics ; NF-kappa B/metabolism ; Olive Oil ; Plant Oils/pharmacology ; Pyrans/pharmacology ; Receptors, Estrogen/metabolism ; Up-Regulation
    Chemical Substances Antineoplastic Agents ; Cyclin-Dependent Kinase Inhibitor p21 ; Iridoids ; NF-kappa B ; Olive Oil ; Plant Oils ; Pyrans ; Receptors, Estrogen ; Cyclin D1 (136601-57-5) ; oleuropein (2O4553545L)
    Language English
    Publishing date 2013-03
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 782617-5
    ISSN 1873-6351 ; 0278-6915
    ISSN (online) 1873-6351
    ISSN 0278-6915
    DOI 10.1016/j.fct.2012.12.009
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Oleuropein induces anti-metastatic effects in breast cancer.

    Hassan, Zeinab K / Elamin, Maha H / Daghestani, Maha H / Omer, Sawsan A / Al-Olayan, Ebtesam M / Elobeid, Mai A / Virk, Promy / Mohammed, Osama B

    Asian Pacific journal of cancer prevention : APJCP

    2012  Volume 13, Issue 9, Page(s) 4555–4559

    Abstract: Breast cancer causes death due to distant metastases in which tumor cells produce matrix metalloproteinase (MMP) enzymes which facilitate invasion. Oleuropein, the main olive oil polyphenol, has anti-proliferative effects. This study aimed to investigate ...

    Abstract Breast cancer causes death due to distant metastases in which tumor cells produce matrix metalloproteinase (MMP) enzymes which facilitate invasion. Oleuropein, the main olive oil polyphenol, has anti-proliferative effects. This study aimed to investigate the effect of oleuropein on the metastatic and anti-metastatic gene expression in the MDA human breast cancer cell line. We evaluated the MMPs and TIMPs gene expression by semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) in treated and untreated cells. This study demonstrated that OL may induce anti-metastatic effects on human breast cancer cells. We found that TIMP1,-3, and -4 were over-expressed after all periods of incubation in treated cancer cells compared to untreated cells, while MMP2 and MMP9 genes were down-regulated, at least initially. Treatment of breast cancer cells with oleuropein could help in prevention of cancer metastasis by increasing the TIMPs and suppressing the MMPs gene expressions.
    MeSH term(s) Analysis of Variance ; Antineoplastic Agents/pharmacology ; Breast Neoplasms/genetics ; Breast Neoplasms/pathology ; Cell Line, Tumor ; Down-Regulation/drug effects ; Gene Expression Regulation, Neoplastic/drug effects ; Humans ; Iridoid Glucosides ; Iridoids ; Matrix Metalloproteinase 2/genetics ; Matrix Metalloproteinase 9/genetics ; Neoplasm Metastasis ; Pyrans/pharmacology ; RNA, Messenger/genetics ; RNA, Messenger/metabolism ; Tissue Inhibitor of Metalloproteinase-1/genetics ; Tissue Inhibitor of Metalloproteinase-3/genetics ; Tissue Inhibitor of Metalloproteinases/genetics ; Up-Regulation/drug effects ; Tissue Inhibitor of Metalloproteinase-4
    Chemical Substances Antineoplastic Agents ; Iridoid Glucosides ; Iridoids ; Pyrans ; RNA, Messenger ; TIMP1 protein, human ; TIMP3 protein, human ; Tissue Inhibitor of Metalloproteinase-1 ; Tissue Inhibitor of Metalloproteinase-3 ; Tissue Inhibitor of Metalloproteinases ; oleuropein (2O4553545L) ; Matrix Metalloproteinase 2 (EC 3.4.24.24) ; Matrix Metalloproteinase 9 (EC 3.4.24.35)
    Language English
    Publishing date 2012-11-20
    Publishing country Thailand
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2218955-5
    ISSN 2476-762X ; 1513-7368
    ISSN (online) 2476-762X
    ISSN 1513-7368
    DOI 10.7314/apjcp.2012.13.9.4555
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Sample size in obesity trials: patient perspective versus current practice.

    Allison, David B / Elobeid, Mai A / Cope, Mark B / Brock, David W / Faith, Myles S / Vander Veur, Stephanie / Berkowitz, Robert / Cutter, Gary / McVie, Theresa / Gadde, Kishore M / Foster, Gary D

    Medical decision making : an international journal of the Society for Medical Decision Making

    2009  Volume 30, Issue 1, Page(s) 68–75

    Abstract: Objective: To evaluate patient opinions on acceptable risks in exchange for a given degree of weight loss and their implications for sample size determination in obesity randomized clinical trials (RCTs).: Design: . Survey of patients entering RCTs ... ...

    Abstract Objective: To evaluate patient opinions on acceptable risks in exchange for a given degree of weight loss and their implications for sample size determination in obesity randomized clinical trials (RCTs).
    Design: . Survey of patients entering RCTs for weight loss in a university-based clinical research setting and power calculations based on their responses. Participants. Men (n = 8) and women (n = 66) between 24 and 73 years of age with body mass indices ranging from 26.8 to 40.5 kg/m(2). Measurements. Survey responses to questions assessing the added risk of serious adverse events (SAEs) or death one is willing to assume for a given degree of weight loss.
    Results: For 5% and 10% weight loss against risk for death per se, the mean acceptable risk tended to be about 3.5%, but the median (0.00) and mode (0.00) suggested that for most individuals, only a risk of < or = 1% would be acceptable. Figures, estimated dropout rates, and base rates of SAEs (including deaths) from recent obesity trials indicate that 1-year 2-group obesity RCTs would need tens of thousands of participants per group to have 80% power to detect risks that are meaningful to patients at the 2-tailed 0.05 alpha level.
    Conclusion: Patient education is needed to explain which risks are realistically detectable in RCTs so that patients may provide truly informed consent, or RCT standards should be modified to meet patients' implicit expectations.
    MeSH term(s) Adult ; Aged ; Data Collection ; Female ; Humans ; Informed Consent ; Male ; Middle Aged ; Obesity ; Patients/psychology ; Randomized Controlled Trials as Topic ; Risk Assessment ; Sample Size ; Weight Loss/physiology ; Young Adult
    Language English
    Publishing date 2009-08-12
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 604497-9
    ISSN 1552-681X ; 0272-989X
    ISSN (online) 1552-681X
    ISSN 0272-989X
    DOI 10.1177/0272989X09340583
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Missing data in randomized clinical trials for weight loss: scope of the problem, state of the field, and performance of statistical methods.

    Elobeid, Mai A / Padilla, Miguel A / McVie, Theresa / Thomas, Olivia / Brock, David W / Musser, Bret / Lu, Kaifeng / Coffey, Christopher S / Desmond, Renee A / St-Onge, Marie-Pierre / Gadde, Kishore M / Heymsfield, Steven B / Allison, David B

    PloS one

    2009  Volume 4, Issue 8, Page(s) e6624

    Abstract: Background: Dropouts and missing data are nearly-ubiquitous in obesity randomized controlled trails, threatening validity and generalizability of conclusions. Herein, we meta-analytically evaluate the extent of missing data, the frequency with which ... ...

    Abstract Background: Dropouts and missing data are nearly-ubiquitous in obesity randomized controlled trails, threatening validity and generalizability of conclusions. Herein, we meta-analytically evaluate the extent of missing data, the frequency with which various analytic methods are employed to accommodate dropouts, and the performance of multiple statistical methods.
    Methodology/principal findings: We searched PubMed and Cochrane databases (2000-2006) for articles published in English and manually searched bibliographic references. Articles of pharmaceutical randomized controlled trials with weight loss or weight gain prevention as major endpoints were included. Two authors independently reviewed each publication for inclusion. 121 articles met the inclusion criteria. Two authors independently extracted treatment, sample size, drop-out rates, study duration, and statistical method used to handle missing data from all articles and resolved disagreements by consensus. In the meta-analysis, drop-out rates were substantial with the survival (non-dropout) rates being approximated by an exponential decay curve (e(-lambdat)) where lambda was estimated to be .0088 (95% bootstrap confidence interval: .0076 to .0100) and t represents time in weeks. The estimated drop-out rate at 1 year was 37%. Most studies used last observation carried forward as the primary analytic method to handle missing data. We also obtained 12 raw obesity randomized controlled trial datasets for empirical analyses. Analyses of raw randomized controlled trial data suggested that both mixed models and multiple imputation performed well, but that multiple imputation may be more robust when missing data are extensive.
    Conclusion/significance: Our analysis offers an equation for predictions of dropout rates useful for future study planning. Our raw data analyses suggests that multiple imputation is better than other methods for handling missing data in obesity randomized controlled trials, followed closely by mixed models. We suggest these methods supplant last observation carried forward as the primary method of analysis.
    MeSH term(s) Data Interpretation, Statistical ; Humans ; Obesity/therapy ; Randomized Controlled Trials as Topic ; Weight Loss
    Language English
    Publishing date 2009-08-13
    Publishing country United States
    Document type Journal Article ; Meta-Analysis ; Research Support, N.I.H., Extramural
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0006624
    Database MEDical Literature Analysis and Retrieval System OnLINE

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