Predictive Utility of Anthropometric Based Cut-offs in Assessing Excess Adiposity among Preschool Children in a Multiethnic Population

ABSTRACT Objective: Screening for childhood obesity is a necessary step in developing appropriate and effective interventions. We evaluated the diagnostic performance of various recommended international anthropometric cut-offs based on body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), triceps skinfold (TSF), and mid-upper arm circumference (MUAC) in predicting excess adiposity (body fat ≥ 25%) in a random sample of Trinidadian preschoolers. Methods: After obtaining written parental consent, weight, height, WC, TSF, and MUAC were measured in 596 children using standard procedures. These were used to calculate BMI for age, WHtR, TSF-for-age z-scores, and MUAC-for-age z-scores. Percentage body fat was measured using a Tanita-531 foot-to-foot bioelectrical impedance analyser (BIA). Sensitivities, specificities and area under the receiver-operating curve analysis and predictive values were then computed in reference to BIA estimates. Results: The prevalence of excess adiposity was 12.2% and 5.1% among males and females, respectively. Sensitivities for the various cut-offs ranged from 20.0% to 75.0% and 57.1% to 96.9% among males and females, respectively. WHO-BMI recommended cut-offs and those based on MUAC z-scores had significantly higher sensitivities in females than in males. TSF z-scores had significantly lower sensitivities compared to those based on BMI and WHtR among males. Similarly, specificities ranged from 81.3% to 99.9% and 79.8% to 99.9% among males and females, respectively. In girls, cut-offs based on TSF z-scores had a higher likelihood ratio than cut-offs from Centers for Disease Control, International Obesity Task Force and WHtR. Diagnostic performance was not associated with ethnicity. Conclusion: Our results suggest that diagnostic performance was associated with gender and the cut-offs used; however, it was not associated with ethnicity.

Development and validation of a simplified height-specific blood pressure cutoffs table for screening hypertension in Chinese children and adolescents / 中华预防医学杂志

Objective@#To develop and validate a simplified height-specific blood pressure cutoffs table for screening hypertension in Chinese children and adolescents.@*Methods@#We developed a simplified height-specific blood pressure cut offs table according to Chinese Blood Pressure Reference for Children and Adolescents aged 7-18 years (WS/T 610-2018) (hereafter referred to as "complex definition"). Populations from Early Warning, Diagnosis and Treatment of Children Cardiovascular Disease Project ("Ji′nan sample") and Shandong Children Cardiovascular Cohort Study Project ("Zibo sample") were used as validation populations for evaluating the screening effect of the simplified table for elevated blood pressure and hypertension in children and adolescents.@*Results@#We developed simplified height-specific blood pressure cutoffs table including 7 height groups and 28 cutoffs. Both Ji′nan and Zibo samples were selected by convenient sampling method, and the former included 7 233 participants aged 7 to 17 years, among whom 3 790 (52.4%) were boys. Latter population included 1 277 participants aged 7 to 11 years, among whom 681 (53.3%) were boys. The simplified table performed well for identifying elevated blood pressure in Ji′nan sample, with values of area under the receiver operating curve (AUC) (95%CI), sensitivity, specificity, and Kappa statistic as 0.96 (0.95-0.97), 93.0%, 98.5% and 0.91, respectively, which were similar with results in Zibo sample [the values were 0.92 (0.90-0.95), 87.0%, 98.0% and 0.85, respectively]. The simplified table also performed well for identifying hypertension in Ji′nan sample with values of AUC (95%CI), sensitivity, specificity, and Kappa statistic as 0.92 (0.91-0.94), 86.9%, 98.1% and 0.85, respectively, which were similar with results in Zibo sample [the values were 0.94 (0.91-0.96), 88.2%, 98.9% and 0.88, respectively].@*Conclusion@#Screening for elevated and high blood pressure based on simplified height-specific blood pressure cutoffs table is easy to use and it shows satisfying effect.

The methods of exploring obesity cutoffs for screening/diagnosing diabetes / 中华流行病学杂志

It is important to establish an appropriate obesity-cutoff method to identify people with diabetes or at high risk of the disease.Aside from restricted cubic splines and fractional polynomial model,the receiver operating characteristic curve is the most frequently one used to define these cutoffs.In this study,we explored the obesity cutoffs across different ethnic populations and evaluated the merits/demerits of different Methods by reviewing the currently used obesity cutoffs.

Puntos de corte de 17-hidroxiprogesterona en la detección de Hiperplasia Suprarrenal Congénita / Cut offs levels of 17-hydroxyprogesterone in screening of Congenital Adrenal Hyperplasia / Pontos de corte da 17-hidroxiprogesterona na detecção de Hiperplasia Adrenal Congênita

El presente estudio investiga la utilidad de determinar puntos de corte ajustados según la edad gestacional y el peso al nacer de neonatos (2-100 días) en la cuantificación de 17-hidroxiprogesterona en muestras de sangre seca en papel de filtro. Se analizaron los resultados de 6.266 determinaciones realizadas en el marco del Programa Nacional de Fortalecimiento de la Detección Precoz de Enfermedades Congénitas. Los datos se dividieron en cuatro grupos; Grupo 1: recién nacido pretérmino con bajo peso; Grupo 2: recién nacido pretérmino con peso normal; Grupo 3: recién nacido a término con bajo peso y Grupo 4: recién nacido a término con peso normal. Se establecieron puntos de corte diferentes a partir del cálculo del percentilo 99 de la distribución de frecuencias. Basado en este análisis se realizó la comparación de la tasa de resultados falsos positivos que se obtuvieron según el punto de corte establecido por el fabricante y los obtenidos en el estudio. Los nuevos puntos de corte obtenidos fueron: 217,72 nmol/L, 102,14 nmol/L, 61,62 nmol/L y 82,38 nmol/L para los grupos 1, 2, 3 y 4 respectivamente. Se evidenció una tasa total de falsos positivos del 1% con los nuevos puntos de corte, significativamente menor a la tasa del 6,2% obtenida al utilizar el punto de corte del fabricante. Esto puso en evidencia que el uso de puntos de corte adecuadamente establecidos para la población en estudio reduce significativamente las complicaciones derivadas de las repeticiones de análisis y eventualmente la tasa de recitaciones, lo cual es una importante contribución a la Salud Pública.

The present work studies the usefulness of determining adjusted cut-offs for the quantification of 17-hydroxyprogesterone in dried blood samples on filter paper, taking into account the gestational age and weight of the neonates. The results of 6266 determinations made within the framework of the National Program of Strengthening Early Detection of Congenital Disease were analysed. Data were divided into groups, Group 1: early established from the calculation of the 99 percentiles of the frequency distribution. New cutoff points were: 217.72 nmol/L, 102.14 nmol/L, 61.62 nmol/L and 82.38 nmol/L for groups 1, 2, 3 and 4 respectively. It showed a total rate of 1% false positives with the new cut-off points, which was significantly lower than the rate of 6.2% obtained using the manufacturer's cutoff. This revealed that the use of properly established cut-offs for the study of population reduces significantly the complications derived fromn analysis repetitions and eventually the recitation rate, which is an important contribution to Public Health.

O presente estudo investiga a utilidade de determinar pontos de corte estabelecidos conforme a idade gestacional e o peso ao nascer de neonatos (2-100 dias) na quantificação da 17-hidroxiprogesterona em amostras de sangue seco em papel filtro. Foram analisados os resultados de 6.266 determinações feitas no âmbito do Programa Nacional de Fortalecimento da Detecção Precoce de Doenças Congênitas. Os dados foram divididos em quatro grupos; Grupo 1: recém-nascido pré-termo com baixo peso, Grupo 2: recém-nascido pré-termo com peso normal, Grupo 3: recém-nascido a termo com baixo peso e Grupo 4: recém-nascido a termo com peso normal e foram estabelecidos pontos de corte diferentes a partir do cálculo do percentil 99 da distribuição de frequências. Com base nesta análise foi realizada a comparação da taxa de resultados falsos positivos obtidos conforme o ponto de corte estabelecido pelo fabricante e os obtidos no estudo. Os novos pontos de corte obtidos foram: 217,72 nmol/L, 102,14 nmol/L, 61,62 nmol/L e 82,38 nmol/L para os grupos 1, 2, 3 e 4, respectivamente. Tornou-se evidente uma taxa total de 1% de falsos positivos, com os novos pontos de corte significativamente menor do que a taxa de 6,2% obtida utilizando o ponto de corte do fabricante. Isto revelou que o uso de pontos de corte de forma adequada estabelecidos para a população em estudo reduz significativamente as complicações decorrentes das repetições de análises e eventualmente a taxa de repetição de novos encontros, o que é uma importante contribuição para a saúde pública.

Screening high-risk population for hypertension and type 2 diabetes among Thais.

Background: waist circumference (WC) and body mass index (BMI) are simple screening tools for hypertension (HT) and type 2 diabetes (DM). Cutoffs of WC for BMI for Asians have been discussed. This study aimed to assess the accuracy of screening tools and associations of WC, BMI with HT and DM. Methods: Data from the national screening programme for metabolic syndrome conducted in 2010 in 21 provinces in the central region of Thailand were analysed. A total of 10 748 participants aged >35 years were included in the analysis with cutoffs of WC set at 90 cm for men, 80 cm for women, and BMI at 23 kg/m2 for both sexes. Results: WC produced low sensitivity and high specificity among male participants, and moderate sensitivity and specificity among female participants, while BMI produced moderate sensitivity and specificity in both sexes. Significant associations were found among those who had high WC only, high BMI only, and both high WC and BMI with HT and DM in both sexes. (males for HT, OR=1.63, 95%CI: 1.15–2.33, OR=1.22, 95%CI: 1.03–1.44 and OR=2.03, 95%CI: 1.07–2.42; males for DM, OR=1.39, 95%CI: 1.05–1.83), OR=1.77, 95%CI: 1.07–2.94 and OR= 2.05, 95%CI: 1.57–2.69, females for HT, OR=1.69: 95%CI 1.38–2.07, OR=1.32; 95%CI: 1.09–1.60 and OR=2.54, 95%CI: 2.11–2.91; females for DM, OR=1.45, 95%CI: 1.08–1.94, OR=1.45, 95%CI: 1.09–1.91 and OR=1.70, 95%CI: 1.39–2.09). When the cutoff WC was lowered among male participants to 85 cm, sensitivity increased, and significant strengths of associations with HT and DM were nearly the same. Conclusion: For Thailand, WC and BMI with appropriate cutoffs can be effective screening tools to recruit high-risk populations into health promotion programmes. However, WC and BMI should be implemented with other screening tools for other risk factors because of their moderate accuracy.

The mini mental state examination: review of cutoff points adjusted to schooling in a large Southern Brazilian sample / Mini exame do estado mental: revisão de pontos de corte ajustados para a escolaridade em uma grande amostra do sul do Brasil

The increase in life expectancy can influence the prevalence of dementias in the population. Instruments that evaluate cognitive functions such as the Mini Mental State Examination (MMSE) are necessary for the investigation of dementia. The supposition that patient score on the MMSE can be influenced by academic level points to the need for establishing cut-off values that take into account educational level. The aim of this study was to review MMSE cut-off values adjusted for schooling in a large southern Brazilian sample. Method: Demographic data and MMSE scores of 968 subjects, of which 162 were dementia patients and 806 healthy participants, were analyzed. The sample was grouped according to education. The cut-off values were established by ROC Curve analysis. Results: The total sample mean age was 70.6±7.3 years, and the mean years of education was 7.2±5.3. The cut-off score of 23 points (sensitivity=86%, specificity=83%) was observed as the optimal level to detect dementia on the MMSE instrument for the overall sample. Regarding level of schooling, the cut-off values were: 21 for the illiterate group (sensitivity=93%, specificity=82%), 22 for the low education group (sensitivity=87%, specificity=82%), 23 for the middle education group (sensitivity=86%, specificity=87%) and 24 for the high education group (sensitivity=81%, specificity=87%). Conclusions: The cut-off values revealed by this analysis, and adjusted for level of schooling, can improve the clinical evaluation of cognitive deficits.

A elevação da expectativa de vida pode influenciar na prevalência das demências na população. Instrumentos que avaliem as funções cognitivas, como o Mini Exame do Estado Mental (MEEM), são necessários para a investigação de demência. A suposição de que o resultado do MEEM de um paciente pode ser influenciado pelo nível de escolaridade demonstra a necessidade do estabelecimento de pontos de corte que levem em consideração a escolaridade. O objetivo deste estudo foi revisar os pontos de corte do MEEM ajustados para a escolaridade em uma grande amostra do sul do Brasil. Método: Dados demográficos e escores do MEEM de 968 indivíduos, 162 pacientes com demência e 806 participantes saudáveis foram analisados. A amostra foi agrupada de acordo com a educação. Para estabelecer os pontos de corte foi utilizada a Curva ROC. Resultados: A média de idade da amostra total foi 70,6±7,3 e a média de anos de estudo foi 7,2±5,3. O ponto de corte 23 (sensibilidade=86%), (especificidade=83%) foi o ponto que melhor detectou demência na amostra total. Considerando o nível de escolaridade, os pontos de corte foram: 21 no grupo de analfabetos (sensibilidade=93%, especificidade=82%), 22 no grupo de baixa escolaridade (sensibilidade=87%, especificidade=82%), 23 no grupo de média escolaridade (sensibilidade=86%, especificidade=87%) e 24 no grupo de alta escolaridade (sensibilidade=81%, especificidade=87%). Conclusões: Os pontos de corte, quando se considera a escolaridade, podem aperfeiçoar a avaliação clínica dos déficits cognitivos.