18 research outputs found

    Relaxing the Independence Assumption in Relative Survival Analysis

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    Quantifying credible cancer survival in competing risk population-based studies is generally done by disease-specific survival analysis when reliable cause of death information is available. Relative survival analysis may be used to estimate disease-specific survival when cause of death is missing and or subject to misspecification and not reliable for practical usage. This method is popular for population-based cancer survival studies using registry data and does not require cause of death information. The standard estimator under the independence assumption is the ratio of all-cause survival in the cancer cohort group to the known expected survival from a healthy reference population. Disease-specific death competes with other causes of mortality, potentially creating dependence among the causes of death. The standard ratio estimate is only valid when death from disease and death from other causes are independent. To relax the independence assumption, we formulate dependence using a copula-based model. Likelihood-based, nonparametric and parametric regression methods are implemented to fit a parametric, a nonparametric and a regression model to the distribution of disease-specific death respectively without the need for cause of death information. We assumed that the copula is known and the distribution of other cause of mortality is derived from the reference population. Since the dependence structure for disease related and other-cause mortality is nonidentifiable and unverifiable from the observed data, we propose a sensitivity analysis, where the analysis is conducted across a range of assumed dependence structures. We demonstrate the practical utility of our method through simulation studies and an application to French breast cancer data.Doctor of Philosoph

    Intakes of Calcium and Phosphorus and Calculated Calcium-to-Phosphorus Ratios of Older Adults: NHANES 2005–2006 Data

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    Background: High intakes of dietary phosphorus (P), relative to calcium (Ca) intake, are associated with a lower calcium:phosphorus ratio (Ca:P) ratio which potentially has adverse health effects, including arterial calcification, bone loss, and death. A substantial percentage of older adults (50 to 70 and 71 plus years) who have a higher risk of fracture rate than younger adults typically have low intakes of dietary Ca that are dominated by higher intakes of dietary P from natural and fortified foods, and lower Ca:P ratios than desirable. Objective: This investigation was undertaken to examine Ca and P intakes and the resulting Ca:P ratios (by mass) across gender and older adult age groups, using data from the National Health and Nutrition Examination Survey (NHANES) 2005–2006. Design: NHANES data are based on a cross-sectional sample of the non-institutionalized United States (US) population within various regions. This sample is selected to be representative of the entire US population at all ages. National Cancer Institute (NCI) methods and SAS survey procedures were used for analyses. Ca:P ratios were calculated using total Ca from both foods and supplements, whereas P intakes were calculated from food composition values and supplements. The amounts of P additives in processed foods are not available. Results: Mean Ca and P intakes demonstrated lower intakes of Ca and higher intakes of P compared to current Recommended Dietary Allowances (RDAs). The Ca:P ratios in older male and female adults were influenced by both low-Ca and high-P dietary consumption patterns. Conclusions: Both low total Ca intakes and high P amounts contribute to lower Ca:P ratios, i.e., ~0.7:1.0, in the consumption patterns of older adults than is recommended by the RDAs, i.e., ~1.5:1.0. Whether Ca:P ratios lower than recommended contribute to increased risk of bone loss, arterial calcification, and all-cause mortality cannot be inferred from these data. Additional amounts of chemical P additives in the food supply may actually reduce even further the Ca:P ratios of older adults of both genders, but, without P additive data from the food industry, calculation of more precise ratios from NHANES 2005–2006 data is not possible

    A Cluster Randomized Trial of Tailored Breastfeeding Support for Women with Gestational Diabetes

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    Background: Women with gestational diabetes mellitus (GDM) and their infants are at increased risk of developing metabolic disease; however, longer breastfeeding is associated with a reduction in these risks. We tested an intervention to increase breastfeeding duration among women with GDM

    The Efficacy of Plant-Based Dietary Program in Patients with Diabetes: A Pilot Study

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    Dietary choices play a key role in insulin sensitivity among diabetes patients. An 8-week pilot study was conducted to evaluate whether a mostly plant-based dietary program will lead to improvement in biochemical markers in adults with diabetes. The dietary program included educational presentations, weekly cooking demonstrations and small group discussions. A sample of thirty-two adults with diabetes (types 1 and 2) were recruited and seventeen (53%) completed the study. Matched-pair tests and Fishers exact tests were used to compare the changes in means and proportion of the participants’ responses. There were changes in HbA1c, lipids, CRP (mg/L), cholesterol (mg/dL), HDL (mg/dL), triglycerides (mg/dL), LDL (mg/dL), non-HDL (mg/dL), Insulin (uIU/mL), AST (U/L), ALT (U/L), weight (lbs), systolic blood pressure (mmHg), diastolic (mmHg). The mean (std) age for the matched pair participant is 60.5 (11.35). Five type 1 and twelve type 2 diabetes patients showed a significant improvement in HbA1c (p = 0.001), weight (p = 0.002), intake of vegetables per day (p-value = 0.003), intake of plant-based protein (p-value \u3c 0.001) and self-reported reduction in fatigue and improvement in energy levels. Our 8-week dietary program showed an improvement in biochemical markers and positive attitudes toward the adoption of plant-based diets

    Benefits for African American and white low-income 7–10-year-old children and their parents taught together in a community-based weight management program in the rural southeastern United States

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    Abstract Background Low-income children and parents are at increased risk for developing overweight and obesity. Therefore, the purpose of this exploratory study was to compare whether African American and white children and parents benefitted equally from a community-based weight management intervention delivered in two rural counties in southeastern North Carolina (N.C.). Methods We compared the efficacy of the Family Partners for Health intervention for African American and white children and their parents by testing the three-way interaction of the intervention group according to visit and race. Results African American children in the intervention group weighed significantly (P = 0.027) less than those in the control group, while white children in the intervention group weighed less than those in the control group, but the difference did not reach statistical significance. African American and white parents in the intervention group weighed less than their respective control groups across all three data collections, but the difference was only significant in the group of white parents (P = 0.010) at the completion of the study. At the completion of the study, African American children in the intervention group received significantly (P = 0.003) more support for physical activity than African American children in the control group. At both time points, white children in the intervention group were not significantly different from those in the control group. African American parents in the intervention group scored slightly worse in the stress management assessment compared to those in the control group, while white parents in the intervention group showed a significantly (P = 0.041) better level of stress management than those in the control group. At the completion of the study, African American parents in the intervention group scored somewhat worse in emotional eating self-efficacy compared to the scores of the African American parents in the control group, while white parents in the intervention group scored significantly (P < 0.001) better than those in the control group. Conclusions We were successful in affecting some outcomes in both African American and white children and parents using the same intervention. Trial registration NCT01378806 Registered June 22, 2011

    Correction to: A cluster randomized controlled trial for child and parent weight management: children and parents randomized to the intervention group have correlated changes in adiposity

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    Erratum After publication of the original article [1] that the surname of author Reuben Adatorwovor was incorrectly typeset as Adatorwover. These errors were introduced during typesetting; thus the publisher apologizes for this error. Additionally, the original manuscript has also been updated to amend this error

    A cluster randomized controlled trial for child and parent weight management: children and parents randomized to the intervention group have correlated changes in adiposity

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    Abstract Background Studies have suggested that obesity is linked within families and that successful interventions involve both the parent and child with obesity. However little information exists regarding similarities in adiposity and weight loss between the parent and child, especially in low socio-economic ethnically diverse households. Methods The purpose of this study was to examine the relationships between the changes from baseline over time in adiposity, weight, health behaviors, and self-efficacy in children (n = 184) and parents (n = 184) participating in an 18-month weight loss program. Within the intervention group only and for each post-baseline time point, Pearson correlation coefficients were computed for children’s changes (from baseline) in adiposity, weight, health behaviors, and self-efficacy, with their parents’ corresponding changes from baseline, to determine how strongly the dyads were correlated. Results At the completion of 18 months, the intervention group parents demonstrated strong positive correlations between parent and child change in waist circumference (r = 0.409, p < 0.001), triceps (r = 0.332, p < 0.001), and subscapular (r = 0.292, p = 0.002) skinfolds. There were no significant correlations between weight, health behaviors, eating, and exercise self-efficacy. Conclusions The results suggest that in the Southern United States low-income parents and their children with obesity are strongly correlated. Trial registration NCT01378806 Retrospectively Registered on June 22, 2011

    A Randomized Trial of Sitagliptin and Spironolactone With Combination Therapy in Hospitalized Adults With COVID-19

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    COVID-19 may cause respiratory distress syndrome and death. Treatment of COVID-19 to prevent complications remains a priority. Objective Our investigation sought to determine whether combination of spironolactone and sitagliptin could reduce mortality for inpatients with SARS-CoV-2 infection. Methods This single-blind, 4-arm, prospective randomized clinical trial was conducted at Shiraz and Bushehr University of Medical Sciences hospitals between December 2020 and April 2021. We randomized hospitalized adult patients with COVID-19 pneumonia into 4 groups: control, combination therapy, sitagliptin add-on, or spironolactone add-on. The primary outcome was the clinical improvement of the patients in the hospital as measured on an 8-point numerical scale. The secondary outcomes included intubation, ICU admission, end organ damages, CT findings, and paraclinical information. Results A total of 263 admitted patients were randomly assigned to control group (87 patients), combination group (60 patients), sitagliptin group (66 patients), and spironolactone group (50 patients). There were no significant differences in baseline characteristics, except for higher age in control group. The intervention groups, especially combination therapy, had better clinical outcomes (clinical score on fifth day of admission: 3.11 ± 2.45 for controls, 1.33 ± 0.50 for combination, 1.68 ± 1.02 for sitagliptin, and 1.64 ± 0.81 for spironolactone; P = 0.004). However, the mortality rate was lower in patients who received spironolactone (21.84% control, 13.33% combination, 13.64% sitagliptin, 10.00% spironolactone; P = 0.275). Our intervention reduced lung infiltration but not the area of involvement in lungs. Conclusion Sitagliptin and spironolactone can potentially improve clinical outcomes of hospitalized COVID-19 patients

    Intakes of Calcium and Phosphorus and Calculated Calcium-to-Phosphorus Ratios of Older Adults: NHANES 2005–2006 Data

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    Background: High intakes of dietary phosphorus (P), relative to calcium (Ca) intake, are associated with a lower calcium:phosphorus ratio (Ca:P) ratio which potentially has adverse health effects, including arterial calcification, bone loss, and death. A substantial percentage of older adults (50 to 70 and 71 plus years) who have a higher risk of fracture rate than younger adults typically have low intakes of dietary Ca that are dominated by higher intakes of dietary P from natural and fortified foods, and lower Ca:P ratios than desirable. Objective: This investigation was undertaken to examine Ca and P intakes and the resulting Ca:P ratios (by mass) across gender and older adult age groups, using data from the National Health and Nutrition Examination Survey (NHANES) 2005–2006. Design: NHANES data are based on a cross-sectional sample of the non-institutionalized United States (US) population within various regions. This sample is selected to be representative of the entire US population at all ages. National Cancer Institute (NCI) methods and SAS survey procedures were used for analyses. Ca:P ratios were calculated using total Ca from both foods and supplements, whereas P intakes were calculated from food composition values and supplements. The amounts of P additives in processed foods are not available. Results: Mean Ca and P intakes demonstrated lower intakes of Ca and higher intakes of P compared to current Recommended Dietary Allowances (RDAs). The Ca:P ratios in older male and female adults were influenced by both low-Ca and high-P dietary consumption patterns. Conclusions: Both low total Ca intakes and high P amounts contribute to lower Ca:P ratios, i.e., ~0.7:1.0, in the consumption patterns of older adults than is recommended by the RDAs, i.e., ~1.5:1.0. Whether Ca:P ratios lower than recommended contribute to increased risk of bone loss, arterial calcification, and all-cause mortality cannot be inferred from these data. Additional amounts of chemical P additives in the food supply may actually reduce even further the Ca:P ratios of older adults of both genders, but, without P additive data from the food industry, calculation of more precise ratios from NHANES 2005–2006 data is not possible

    Intakes of Calcium and Phosphorus and Calculated Calcium-to-Phosphorus Ratios of Older Adults: NHANES 2005–2006 Data

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    Background: High intakes of dietary phosphorus (P), relative to calcium (Ca) intake, are associated with a lower calcium:phosphorus ratio (Ca:P) ratio which potentially has adverse health effects, including arterial calcification, bone loss, and death. A substantial percentage of older adults (50 to 70 and 71 plus years) who have a higher risk of fracture rate than younger adults typically have low intakes of dietary Ca that are dominated by higher intakes of dietary P from natural and fortified foods, and lower Ca:P ratios than desirable. Objective: This investigation was undertaken to examine Ca and P intakes and the resulting Ca:P ratios (by mass) across gender and older adult age groups, using data from the National Health and Nutrition Examination Survey (NHANES) 2005–2006. Design: NHANES data are based on a cross-sectional sample of the non-institutionalized United States (US) population within various regions. This sample is selected to be representative of the entire US population at all ages. National Cancer Institute (NCI) methods and SAS survey procedures were used for analyses. Ca:P ratios were calculated using total Ca from both foods and supplements, whereas P intakes were calculated from food composition values and supplements. The amounts of P additives in processed foods are not available. Results: Mean Ca and P intakes demonstrated lower intakes of Ca and higher intakes of P compared to current Recommended Dietary Allowances (RDAs). The Ca:P ratios in older male and female adults were influenced by both low-Ca and high-P dietary consumption patterns. Conclusions: Both low total Ca intakes and high P amounts contribute to lower Ca:P ratios, i.e., ~0.7:1.0, in the consumption patterns of older adults than is recommended by the RDAs, i.e., ~1.5:1.0. Whether Ca:P ratios lower than recommended contribute to increased risk of bone loss, arterial calcification, and all-cause mortality cannot be inferred from these data. Additional amounts of chemical P additives in the food supply may actually reduce even further the Ca:P ratios of older adults of both genders, but, without P additive data from the food industry, calculation of more precise ratios from NHANES 2005–2006 data is not possible
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