Category: Statistics

Public Health Nutr. 2021 Aug 25:1-22. doi: 10.1017/S1368980021003669. Online ahead of print.

ABSTRACT

OBJECTIVE: Neck circumference (NC) is currently used as an embryonic marker of obesity and its associated risks. But its use in clinical evaluations and other epidemiological purposes requires sex and age-specific standardized cut-offs which are still scarce for the Pakistani pediatric population. We therefore developed sex and age- specific growth reference charts for NC for Pakistani children and adolescents aged 2-18 years.

DESIGN: Cross-sectional multi-ethnic anthropometric survey (MEAS) study.

SETTING: Multan, Lahore, Rawalpindi and Islamabad.

PARTICIPANTS: The dataset of 10,668 healthy Pakistani children and adolescents aged 2 to 18 years collected in MEAS were used. Information related to age, sex and NC were taken as study variables. The lambda-mu-sigma (LMS) and quantile regression (QR) methods were applied to develop growth reference charts for NC.

RESULTS: The 5th, 10th, 25th, 50th, 75th, 90th and 95th smoothed percentile values of NC were presented. The centile values showed that neck size increased with age in both boys and girls. During 8 and 14 years of age, girls were found to have larger NC than boys. A comparison of NC median (50th) percentile values with references from Iranian and Turkish populations reveals substantially lower NC percentiles in Pakistani children and adolescents compared to their peers in the reference population.

CONCLUSION: The comparative results suggest that the uses of NC references of developed countries are inadequate for Pakistani children. A small variability between empirical centiles and centiles obtained by QR procedure recommends that growth charts should be constructed by QR as an alternative method.

PMID:34431474 | DOI:10.1017/S1368980021003669

Crit Rev Clin Lab Sci. 2021 Aug 25:1-20. doi: 10.1080/10408363.2021.1956423. Online ahead of print.

ABSTRACT

Peak stimulated growth hormone (GH) levels are known to decrease with increasing body mass index (BMI), possibly leading to overdiagnosis of GH deficiency (GHD) in children with overweight and obesity. However, current guidelines do not guide how to interpret the peak GH values of these children. This systematic review and meta-analysis aimed to study the effect of the BMI standard deviation score (SDS) on stimulated peak GH values in children, to identify potential moderators of this association, and to quantify the extent to which peak GH values in children with obesity are decreased. This systematic review was performed by the PRISMA guidelines. Medline, Embase, Cochrane, Web of Science, and Google Scholar databases were searched for studies reporting the impact of weight status on peak GH in children. Where possible, individual participant data was extracted and/or obtained from authors. Quality and risk of bias were evaluated using the Scottish Intercollegiate Guidelines Network (SIGN) checklists. The primary outcome was the association between peak GH values and BMI SDS. The pooled correlation coefficient r, 95% confidence interval (CI), and heterogeneity statistic I² were calculated under a multilevel, random-effects model. In addition, exploratory moderator analyses and meta-regressions were performed to investigate the effects of sex, pubertal status, presence of syndromic obesity, mean age and mean BMI SDS on the study level. For the individual participant dataset, linear mixed-models regression analysis was performed with BMI SDS as the predictor and ln(peak GH) as the outcome, accounting for the different studies and GH stimulation agents used. In total, 58 studies were included, providing data on n = 5135 children (576 with individual participant data). Thirty-six (62%) studies had high, 19 (33%) medium, and 3 (5%) low risks of bias. Across all studies, a pooled r of -0.32 (95% CI -0.41 to -0.23, n = 2434 patients from k = 29 subcohorts, I² = 75.2%) was found. In meta-regressions, larger proportions of males included were associated with weaker negative correlations (p = 0.04). Pubertal status, presence of syndromic obesity, mean age, and mean BMI SDS did not moderate the pooled r (all p > 0.05). Individual participant data analysis revealed a beta of -0.123 (95% CI -0.160 to -0.086, p < 0.0001), i.e. per one-point increase in BMI SDS, peak GH decreases by 11.6% (95% CI 8.3-14.8%). To our knowledge, this is the first systematic review and meta-analysis to investigate the impact of BMI SDS on peak GH values in children. It showed a significant negative relationship. Importantly, this relationship was already present in the normal range of BMI SDS and could lead to overdiagnosis of GHD in children with overweight and obesity. With the ever-rising prevalence of pediatric obesity, there is a need for BMI (SDS)-specific cutoff values for GH stimulation tests in children. Based on the evidence from this meta-analysis, we suggest the following weight status-adjusted cutoffs for GH stimulation tests that have cutoffs for children with normal weight of 5, 7, 10, and 20 µg/L: for overweight children: 4.6, 6.5, 9.3, and 18.6 µg/L; and for children with obesity: 4.3, 6.0, 8.6, and 17.3 µg/L.

PMID:34431447 | DOI:10.1080/10408363.2021.1956423

Neurol Res. 2021 Aug 25:1-8. doi: 10.1080/01616412.2021.1959775. Online ahead of print.

ABSTRACT

BACKGROUND: : Various tools are currently available to quantify the risks of adverse clinical outcomes after an ischemic stroke. This study aimed to validate and compare prognostic scales among Chinese patients with ischemic stroke.

METHODS: : We compared three stroke prognostic scales (Stroke Prognostication using Age and the National Institutes of Health Stroke Scale-100 [SPAN-100], Totaled Health Risks in Vascular Events [THRIVE], and Acute Stroke Registry and Analysis of Lausanne [ASTRAL]) in 3870 Chinese patients with ischemic stroke from the China Antihypertensive Trial in Acute Ischemic Stroke (CATIS). The 2-year primary outcome was a combination of death and major disability (modified Rankin Scale score ≥3).

RESULTS: : Among all the scales, the ASTRAL score had the best accuracy for predicting 2-year prognosis in Chinese patients with ischemic stroke. The C-statistic of the ASTRAL score for the 2-year primary outcome was 0.79 (95% confidence interval [CI]: 0.78-0.80), and the Hosmer-Lemeshow goodness-of-fit test showed that the ASTRAL score fitted Chinese patients with ischemic stroke well (χ² = 9.83, P = 0.277). The incidences of the primary outcome in the <5%, 5%-9.9%, 10%-19.9%, and ≥20% risk groups based on the ASTRAL scores were 3.93%, 7.55%, 14.29%, and 41.81%, respectively (odds ratio: 1.23; 95% CI: 1.21-1.26; P < 0.001).

CONCLUSION: : The ASTRAL score had higher efficacy than the SPAN-100 and THRIVE scores in predicting 2-year adverse outcomes among Chinese patients with ischemic stroke, suggesting that it could be a valuable risk assessment tool for the 2-year prognosis of such patients.

PMID:34431455 | DOI:10.1080/01616412.2021.1959775

Ann Med. 2021 Dec;53(1):1502-1508. doi: 10.1080/07853890.2021.1968027.

ABSTRACT

Objectives: Early fetal demise (absence of cardiac activity in a visible fetus) is a very common event, but there are no reliable biomarkers to predict it. The purpose of the study was to assess the association of platelet parameters with early fetal demise.Methods: In this case-control study, we included women with normal deliveries or those ultrasound diagnosed as early fetal demise. For those who were identified with early fetal demise, the platelet parameters were analyzed before the ultrasound diagnosis, which is based on the absence of either an embryo within a gestational sac or cardiac activity in a visible embryo in the 5-10 weeks of gestation. The association between the risk of early fetal demise with the women’s mean platelet volume (MPV) and platelet counts was calculated by logistic regression. Duplicate measurements of platelet aggregation were performed with VerifyNow. Results: In total, 99 women identified with early fetal demise and 170 women who had an uncomplicated pregnancy with normal delivery from January 2017 and August 2020 were included in the study. We found that platelet counts in the early fetal demise group were significantly higher than healthy pregnancies. In addition, platelet reactivity is higher in the normal delivery group than those in early fetal demise group (p < .05). High levels of platelet counts resulted in an adjusted odds ratio (OR) of 2.075 (95% confidence interval [95% CI], 1.215-3.544; p = .008) for early fetal demise. Conclusions: Increased platelet counts in the first trimester may be a predictor for the risk of early fetal demise.

PMID:34431412 | DOI:10.1080/07853890.2021.1968027

Neurol Res. 2021 Aug 25:1-10. doi: 10.1080/01616412.2021.1967678. Online ahead of print.

ABSTRACT

To systematically compare 27 ICH models with regard to mortality and functional outcome at 1-month, 3-month and 1-year after ICH. The validation cohort was derived from the Beijing Registration of Intracerebral Hemorrhage. Poor functional outcome was defined as modified Rankin Scale score (mRS) ≥3 at 1-month, 3-month and 1-year after ICH, respectively. The area under the receiver operating characteristic curve (AUROC) and Hosmer-Lemeshow goodness-of-fit test were used to assess model discrimination and calibration. A total number of 1575 patients were included. The mean age was 57.2 ± 14.3 and 67.2% were male. The median NIHSS score on admission was 11 (IQR: 3-21). For predicting mortality at 3-month after ICH, AUROC of 27 ICH models ranged from 0.604 to 0.856. In pairwise comparison, the ICH-FOS (0.856, 95%CI = 0.835-0.878, P < 0.001) showed statistically better discrimination than other models for mortality at 3-month after ICH (all P < 0.05). For predicting poor functional outcome (mRS≥3) at 3-month after ICH, AUROC of 27 ICH models ranged from 0.602 to 0.880. In pairwise comparison with other prediction models, the ICH-FOS was superior in predicting poor functional outcome at 3-month after ICH (all P < 0.001). The ICH-FOS showed the largest Cox and Snell R-square. Similar results were verified for mortality and poor functional outcome at 1-month and 1-year after ICH. Several risk models are externally validated to be effective for risk stratification and outcome prediction after ICH, especially the ICH-FOS, which would be useful tools for personalized care and clinical trial in ICH.

PMID:34431446 | DOI:10.1080/01616412.2021.1967678

Nutr Hosp. 2021 Aug 25. doi: 10.20960/nh.03606. Online ahead of print.

ABSTRACT

IIntroduction: Vitamin D maintains the concentration of calcium and phosphorus within the physiological range allowing normal metabolism and bone mineralization. Recently, vitamin D deficiency has been related not only with rickets, but also with increased risk of other pathologies. The aim of this descriptive observational cross-sectional study was to know vitamin D concentration levels in a healthy pediatric population and the current situation of prophylaxis. Vitamin D determination was measured by serum 25-hydroxyvitamin D (25(OH)D) concentration.

METHODS: 258 healthy patients between 3 months to 15 years were enrolled (6.77 ± 3.95 years; 73,6% male).

RESULTS: The mean value of 25-hydroxyvitamin D was 26.60 ng/ml ± 8.02 ng/ml, and up to 20.9% of the population showed deficient level. Statistical significant differences of vitamin D levels were observed between ages (p= 0.002), ethnicity groups (p= 0.038) and skin types (p= 0.000). In addition, a higher prevalence of vitamin D deficiency in children who had never received vitamin D supplementation previously (41.6%) was observed compared to those that had taken supplementation in the first year of life (16.7%).

CONCLUSION: Our study shows a high prevalence of vitamin D deficiency among healthy children and the benefit of vitamin D supplement prophylaxis.

PMID:34431303 | DOI:10.20960/nh.03606

J Am Heart Assoc. 2021 Aug 25:e020717. doi: 10.1161/JAHA.120.020717. Online ahead of print.

ABSTRACT

Background The prevalence of obesity in the population has increased in parallel with increasing rates of adverse pregnancy outcomes (APOs). Quantifying contemporary trends in prepregnancy obesity and associations with interrelated APOs (preterm birth, low birth weight, and pregnancy-associated hypertension) together and individually can inform prevention strategies to optimize cardiometabolic health in women and offspring. Methods and Results We performed a serial, cross-sectional study using National Center for Health Statistics birth certificate data including women aged 15 to 44 years with live singleton births between 2013 and 2018, stratified by race/ethnicity (non-Hispanic White, non-Hispanic Black, Hispanic, and non-Hispanic Asian). We quantified the annual prevalence of prepregnancy obesity (body mass index ≥30.0 kg/m²; body mass index ≥27.5 kg/m² if non-Hispanic Asian). We then estimated adjusted associations using multivariable logistic regression (odds ratios and population attributable fractions) for obesity-related APOs compared with normal body mass index (18.5-24.9 kg/m²; 18.5-22.9 kg/m² if non-Hispanic Asian). Among 20 139 891 women, the prevalence of prepregnancy obesity increased between 2013 and 2018: non-Hispanic White (21.6%-24.8%), non-Hispanic Black (32.5%-36.2%), Hispanic (26.0%-30.5%), and non-Hispanic Asian (15.3%-18.6%) women (P-trend < 0.001 for all). Adjusted odds ratios (95% CI) for APOs associated with obesity increased between 2013 and 2018, and by 2018, ranged from 1.27 (1.25-1.29) in non-Hispanic Black to 1.94 (1.92-1.96) in non-Hispanic White women. Obesity was most strongly associated with pregnancy-associated hypertension and inconsistently associated with preterm birth and low birth weight. Population attributable fractions of obesity-related APOs increased over the study period: non-Hispanic White (10.6%-14.7%), non-Hispanic Black (3.7%-6.9%), Hispanic (7.0%-10.4%), and non-Hispanic Asian (7.4%-9.7%) women (P-trend < 0.01 for all). Conclusions The prevalence of prepregnancy obesity and burden of obesity-related APOs have increased, driven primarily by pregnancy-associated hypertension, and vary across racial/ethnic subgroups.

PMID:34431359 | DOI:10.1161/JAHA.120.020717

J Am Heart Assoc. 2021 Aug 25:e022087. doi: 10.1161/JAHA.121.022087. Online ahead of print.

ABSTRACT

Background White matter abnormalities are a common feature of aging and Alzheimer disease, and tend to be more severe among Black individuals. However, the extent to which white matter abnormalities relate to amyloid deposition, a marker of Alzheimer pathology, remains unclear. This cross-sectional study examined the association of white matter abnormalities with cortical amyloid in a community sample of older adults without dementia and examined the moderating effect of race. Methods and Results Participants from the ARIC-PET (Atherosclerosis Risk in Communities-Positron Emission Tomography) study underwent brain magnetic resonance imaging, which quantified white matter hyperintensity volume and microstructural integrity using diffusion tensor imaging. Participants received florbetapir positron emission tomography imaging to measure brain amyloid. Associations between measures of white matter structure and elevated amyloid status were examined using multivariable logistic regression. Among 322 participants (43% Black), each SD increase in white matter hyperintensity volume was associated with a greater odds of elevated amyloid (odds ratio [OR], 1.37; 95% CI, 1.03-1.83) after adjusting for demographic and cardiovascular risk factors. In race-stratified analyses, a greater white matter hyperintensity volume was more strongly associated with elevated amyloid among Black participants (OR, 2.00; 95% CI, 1.15-3.50), compared with White participants (OR, 1.29; 95% CI, 0.89-1.89). However, the race interaction was not statistically significant (P interaction=0.09). We found no association between white matter microstructure and elevated amyloid. Conclusions The results suggest a modest positive relationship between white matter hyperintensity and elevated amyloid in older adults without dementia. Although the results indicate that this association is nonsignificantly stronger among Black participants, these findings will need to be confirmed or refuted using larger multiracial cohorts.

PMID:34431373 | DOI:10.1161/JAHA.121.022087

J Assoc Physicians India. 2021 Jul;69(7):11-12.

ABSTRACT

INTRODUCTION: The term post TB sequelae is usually used to describe the destructive lung parenchymal changes due to pulmonary tuberculosis, which occur over years, and cause chronic airway obstruction as well as restriction. Furthermore, post TB sequelae and COPD are common causes of acute exacerbation with respiratory failure in Indian setting.

AIM OF THE STUDY: To compare the outcome of patients with post TB sequelae and COPD admitted with respiratory failure Methodes: 62 Post TB sequelae and 79 COPD patients admitted in respiratory failure were treated as per standard ICU protocols. Outcome of these patients in these groups were compared with respect to mortality, morbidity and requirement of type ventilatory support.

RESULTS: It was observed that duration of stay, morbidity and mortality in these groups was comparable and difference was not statistically significant.

CONCLUSION: The presentation and outcome of COPD and Post TB destroyed lung patients is similar, so Post TB Destroyed lung patients should be treated as per COPD guidelines.

PMID:34431271

ACS Synth Biol. 2021 Aug 25. doi: 10.1021/acssynbio.1c00244. Online ahead of print.

ABSTRACT

Chemical reaction networks (CRNs) based on DNA strand displacement (DSD) can be used as an effective programming language for solving various mathematical problems. In this paper, we design three chemical reaction modules by using the DNA strand displacement reaction as the basic principle, with a weighted reaction module, sum reaction module, and threshold reaction module. These modules are used as basic elements to form chemical reaction networks that can be used to solve 0-1 integer programming problems. The problem can be solved through the three steps of weighting, sum, and threshold, and then the results of the operations can be expressed through a single-stranded DNA output with fluorescent molecules. Finally, we use biochemical experiments and Visual DSD simulation software to verify and evaluate the chemical reaction networks. The results have shown that the DSD-based chemical reaction networks constructed in this paper have good feasibility and stability.

PMID:34431290 | DOI:10.1021/acssynbio.1c00244