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To date, no studies comparing the prevalence of hepatitis E virus (HEV) infection between the general and human immunodeficiency virus 2 (HIV-2) populations are available. With the purpose of filling this gap, this prevalence was assessed in the HIV-2 population from central Portugal. HEV seropositivity was 19.4%, which did not differ significantly from that found in the matched control population, and was not associated with CD4 cell count, HIV-2 viral load, and geographic origin or travel history to regions considered highly endemic for HEV. The results suggest that HIV-2 is not a risk factor for HEV infection, neither for an increased occurrence of chronic HEV infection.
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Patients with coronavirus disease-2019 may be discharged based on clinical resolution of symptoms, and evidence for viral RNA clearance from the upper respiratory tract. Understanding the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral clearance profile is crucial to establish a re-testing plan on discharge and ending isolation of patients. We aimed to evaluate the number of days that a patient needed to achieve undetectable levels of SARS-CoV-2 in upper respiratory tract specimens (nasopharyngeal swab and/or an oropharyngeal swab). The clearance and persistence of viral RNA was evaluated in two groups of positive patients: those who achieved two negative reverse transcription-polymerase chain reaction (RT-PCR) tests and those who kept testing positive. Patients were organized thereafter in two subgroups, mild illness patients discharged home and inpatients who had moderate to severe illness. Results from RT-PCR tests were then correlated with results from the evaluation of the immune response. The study evidenced that most patients tested positive for more than 2 weeks and that persistence of viral RNA is not necessarily associated with severe disease but may result from a weaker immune response instead.
Assuntos
COVID-19/diagnóstico , Alta do Paciente/estatística & dados numéricos , RNA Viral/genética , SARS-CoV-2/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/imunologia , COVID-19/patologia , COVID-19/virologia , Teste para COVID-19/métodos , Criança , Convalescença , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Orofaringe/virologia , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Índice de Gravidade de DoençaRESUMO
Introduction: HIV late presentation (LP) remains excessive in Europe. We aimed to analyze the factors associated with late presentation in the MSM population newly diagnosed with HIV in Portugal between 2014 and 2019. Methods: We included 391 newly HIV-1 diagnosed Men who have Sex with Men (MSM), from the BESTHOPE project, in 17 countrywide Portuguese hospitals. The data included clinical and socio-behavioral questionnaires and the viral genomic sequence obtained in the drug resistance test before starting antiretrovirals (ARVs). HIV-1 subtypes and epidemiological surveillance mutations were determined using different bioinformatics tools. Logistic regression was used to estimate the association between predictor variables and late presentation (LP). Results: The median age was 31 years, 51% had a current income between 501-1,000 euros, 28% were migrants. 21% had never been tested for HIV before diagnosis, with 42.3% of MSM presenting LP. 60% were infected with subtype B strains. In the multivariate regression, increased age at diagnosis, higher income, lower frequency of screening, STI ever diagnosed and higher viral load were associated with LP. Conclusion: Our study suggests that specific subgroups of the MSM population, such older MSM, with higher income and lower HIV testing frequency, are not being targeted by community and clinical screening services. Overall, targeted public health measures should be strengthened toward these subgroups, through strengthened primary care testing, expanded access to PrEP, information and promotion of HIV self-testing and more inclusive and accessible health services.
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Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Adulto , Homossexualidade Masculina , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Portugal/epidemiologia , Europa (Continente)RESUMO
The increasing intake of ultra-processed (UP) foods is causing changes in the profile of food and nutrient consumption, negatively influencing consumer behavior. The present study aimed to evaluate the influence of UP foods on the diet of Brazilian adults, verifying the association between its increasing contribution to total energy and trends in the consumption of other NOVA groups, food subgroups, energy consumption, and macro- and micronutrients. We conducted an observational, cross-sectional study of a probability sample of 921 manufacturing workers in the state of Rio Grande do Norte, Brazil, from a combined stratified and two-stage survey. Trends in consumption across quintiles of UP food contribution to the total energy intake were tested with linear regression. The results showed that higher UP food consumption is associated with a higher intake of energy, carbohydrates and total-, mono- and polyunsaturated fats, saturated fats and trans fats, and the micronutrients calcium, iron and thiamine; and higher consumption of ready-to-eat foods, accompanied by lower consumption of foods that require preparation, such as beans, tubers and roots, vegetables and fruits, which may represent a risk for the development of non-transmissible chronic diseases in this population.
Assuntos
Fast Foods , Alimento Processado , Adulto , Humanos , Brasil , Estudos Transversais , Valor Nutritivo , Manipulação de Alimentos , Dieta , Ingestão de Energia , MicronutrientesRESUMO
Etravirine (ETR) is a non-nucleoside analogue reverse transcriptase inhibitor (NNRTI) with a high genetic barrier to the development of resistance and with potential activity against Human immunodeficiency virus type 1 (HIV-1) strains resistant to first-generation NNRTIs. The objective of this study was to investigate the prevalence of ETR resistance associated mutations (RAMs) in HIV-1 strains isolated from infected individuals failing efavirenz (EFV), as well as to evaluate possible differences in the distribution of ETR RAMs between subtype B and non-B genetic variants. Nucleotide sequences of the protease and partial reverse transcriptase (RT) coding regions of the pol gene of 55 HIV-1 strains isolated from infected individuals failing EFV on regular follow-up at a reference center in Portugal, were retrospectively analyzed. The most prevalent ETR RAMs observed were L100I, V90I, and K101E, with a prevalence of 16.4% (n = 9), 9.1% (n = 5), and 5.5% (n = 3), respectively. Overall, 47.3% (n = 26) of the nucleotide sequences had at least one ETR RAM: 38.2% (n = 21) had one ETR RAM, 7.3% (n = 4) had two ETR RAMs and 1.8% (n = 1) had three ETR RAMs. No statistically significant differences were found in the distribution of ETR RAMs between subtype B and non-B genetic variants. The results demonstrate that ETR rescue therapy is a viable option in treatment-experienced individuals failing EFV and suggests that ETR may be equally useful in HIV-1 infections caused by different genetic variants.
Assuntos
Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/genética , Piridazinas/farmacologia , Alcinos , Fármacos Anti-HIV/uso terapêutico , Benzoxazinas/uso terapêutico , Ciclopropanos , Genótipo , Infecções por HIV/tratamento farmacológico , Protease de HIV/genética , Transcriptase Reversa do HIV/genética , HIV-1/classificação , HIV-1/isolamento & purificação , Humanos , Proteínas Mutantes/genética , Mutação de Sentido Incorreto , Nitrilas , Portugal , Prevalência , Pirimidinas , Estudos Retrospectivos , Falha de TratamentoRESUMO
Objective: To describe and analyze transmitted drug resistance (TDR) between 2014 and 2019 in newly infected patients with HIV-1 in Portugal and to characterize its transmission networks. Methods: Clinical, socioepidemiological, and risk behavior data were collected from 820 newly diagnosed patients in Portugal between September 2014 and December 2019. The sequences obtained from drug resistance testing were used for subtyping, TDR determination, and transmission cluster (TC) analyses. Results: In Portugal, the overall prevalence of TDR between 2014 and 2019 was 11.0%. TDR presented a decreasing trend from 16.7% in 2014 to 9.2% in 2016 (p for-trend = 0.114). Multivariate analysis indicated that TDR was significantly associated with transmission route (MSM presented a lower probability of presenting TDR when compared to heterosexual contact) and with subtype (subtype C presented significantly more TDR when compared to subtype B). TC analysis corroborated that the heterosexual risk group presented a higher proportion of TDR in TCs when compared to MSMs. Among subtype A1, TDR reached 16.6% in heterosexuals, followed by 14.2% in patients infected with subtype B and 9.4% in patients infected with subtype G. Conclusion: Our molecular epidemiology approach indicates that the HIV-1 epidemic in Portugal is changing among risk group populations, with heterosexuals showing increasing levels of HIV-1 transmission and TDR. Prevention measures for this subpopulation should be reinforced.
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The aim of this study was to analyze the spatial distribution of excess weight in Brazil and its correlation with household food insecurity, purchase of foods by type of processing, and Human Development Index (HDI). An ecological study was undertaken using data from three surveys conducted by the Brazilian Institute of Geography and Statistics. Spatial analysis techniques were used to perform univariate and bivariate analysis. The prevalence of excess weight was 34.2% (CI 95% 33.8-34.6%). Excess weight showed a moderate and significant spatial autocorrelation (0.581; p = 0.01), with higher prevalence in states in the South, Southeast and Center-West regions. A positive moderate spatial correlation was shown between the prevalence of excess weight and HDI (0.605; p < 0.05) and purchase of ultra-processed foods (0.559; p < 0.05), while a negative moderate spatial correlation was observed between prevalence of excess weight and household food insecurity (-0.561; p < 0.05). It can be concluded that there is an unequal distribution of excess weight across Brazil. The highest prevalence rates were found in states in the Southeast, South, and Center-West regions, associated with higher HDI values and higher ultra-processed food purchases as a proportion of overall household food purchases.
O objetivo foi analisar a distribuição espacial da prevalência de excesso de peso e sua correlação com insegurança alimentar, aquisição de alimentos por tipo de processamento e Índice de Desenvolvimento Humano (IDH), no Brasil. Estudo ecológico, com dados de três inquéritos do Instituto Brasileiro de Geografia e Estatística (IBGE). Utilizou-se técnicas de estatística espacial para análise univariada e bivariada. A prevalência de excesso de peso encontrada para o Brasil foi de 34,2% (IC95% 33,8-34,6%). O excesso de peso apresentou autocorrelação espacial moderada (0,581; p = 0,01) e maiores prevalências nos estados das regiões Sul, Sudeste e Centro-Oeste. As prevalências de excesso de peso apresentaram correlação espacial positiva e moderada com o IDH (0,605; p< 0,05), proporção de aquisição domiciliar de produtos alimentícios ultraprocessados (0,559; p< 0,05); e correlação negativa e moderada com a prevalência de domicílios em insegurança alimentar (-0,561; p< 0,05). Conclui-se que a ocorrência de excesso de peso encontrava-se desigualmente distribuída no território brasileiro. As prevalências mais elevadas foram encontradas nos estados do Sudeste, Sul e Centro-Oeste, associadas a maiores valores de IDH e proporções de aquisição de produtos alimentícios ultraprocessados.
Assuntos
Comportamento do Consumidor/estatística & dados numéricos , Fast Foods/estatística & dados numéricos , Abastecimento de Alimentos/estatística & dados numéricos , Sobrepeso/epidemiologia , Adolescente , Adulto , Peso Corporal , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Prevalência , Análise Espacial , Adulto JovemRESUMO
Changes in eating behavior of adolescents are associated with high consumption of processed and ultra-processed foods. This study evaluated the association between these foods and the prevalence of inadequate micronutrient intake in adolescents. A cross-sectional study was conducted with 444 adolescents from public schools in the city of Natal, northeastern Brazil. The adolescents' habitual food consumption was evaluated using two 24-hour dietary recalls. Foods were categorized according to the degree of processing (processed and ultra-processed) and distributed into energy quartiles, using the NOVA classification system. Inadequacies in micronutrient intake were assessed using the estimated average requirement (EAR) as the cutoff point. Multivariate logistic regression models were used to estimate the relationship between energy percentage from processed and ultra-processed foods and prevalence of inadequate micronutrient intake. The mean (Standard Deviation (SD)) consumption of total energy from processed foods ranged from 5.8% (1.7%) in Q1 to 20.6% (2.9%) in Q4, while the mean consumption of total energy from ultra-processed foods ranged from 21.4% (4.9%) in Q1 to 61.5% (11.7%) in Q4. The rates of inadequate intake of vitamin D, vitamin E, folate, calcium, and selenium were above 80% for both sexes across all age groups. Energy consumption from processed foods was associated with higher prevalence of inadequate selenium intake (p < 0.01) and lower prevalence of inadequate vitamin B1 intake (p = 0.04). Energy consumption from ultra-processed foods was associated with lower prevalence of inadequate zinc and vitamin B1 intake (p < 0.01 and p = 0.03, respectively). An increase in the proportion of energy obtained from processed and ultra-processed foods may reflect higher prevalence of inadequate selenium intake and lower prevalence of vitamin B1 and zinc inadequacy.
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Ingestão de Energia , Fast Foods/efeitos adversos , Selênio/metabolismo , Deficiência de Tiamina/epidemiologia , Tiamina/metabolismo , Zinco/metabolismo , Adolescente , Fenômenos Fisiológicos da Nutrição do Adolescente , Brasil , Criança , Fast Foods/estatística & dados numéricos , Feminino , Humanos , Masculino , Recomendações Nutricionais , Instituições Acadêmicas/estatística & dados numéricos , Selênio/deficiência , População Urbana/estatística & dados numéricos , Zinco/deficiênciaRESUMO
The objective of this study was to assess whether the Brazilian Workers' Food Program (WFP) is associated with changes in the nutritional status of workers in the transformation industry. We conducted a cross-sectional, observational, comparative study, based on prospectively collected data from a combined stratified and two-stage probability sample of workers from 26 small and medium size companies, 13 adherent and 13 non-adherent to the WFP, in the food, mining and textile sectors. Study variables were body mass index (BMI), waist circumference (WC), and dietary intake at lunch obtained by 24-hour dietary recall. Data were analyzed with nested mixed effects linear regression with adjustment by subject variables. Sampling weights were applied in computing population parameters. The final sample consisted of 1069 workers, 541 from WFP-adherent and 528 from WFP non-adherent companies. The groups were different only in education level, income and in-house training. Workers in WFP-adherent companies have greater BMI (27.0 kg/m2 vs. 26.0 kg/m2, p = 0.002) and WC (87.9 cm vs. 86.5, p = 0.04), higher prevalence of excessive weight (62.6% vs. 55.5%, p<0.001) and of increased WC (49.1% vs. 39.9%). Workers of WFP companies have lower intake of saturated fat (-1.34 g, p<0.01) and sodium (-0.3 g, p<0.01) at lunch. In conclusion, this study showed that workers of companies adherent to the Brazilian WFP have greater rates of excessive weight and increased cardiovascular risk-a negative finding-as well as lower intake of sodium and saturated fat-a positive finding. Therefore, the WFP needs to be revisited and its aims redefined according to the current epidemiological status of the target population of the program.
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Assistência Alimentar/normas , Indústria Manufatureira , Estado Nutricional , Local de Trabalho , Adulto , Índice de Massa Corporal , Brasil/epidemiologia , Estudos Transversais , Dieta , Feminino , Abastecimento de Alimentos/estatística & dados numéricos , Fidelidade a Diretrizes/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Serviços de Saúde do Trabalhador/normas , Circunferência da Cintura , Recursos HumanosRESUMO
Resumo O objetivo foi analisar a distribuição espacial da prevalência de excesso de peso e sua correlação com insegurança alimentar, aquisição de alimentos por tipo de processamento e Índice de Desenvolvimento Humano (IDH), no Brasil. Estudo ecológico, com dados de três inquéritos do Instituto Brasileiro de Geografia e Estatística (IBGE). Utilizou-se técnicas de estatística espacial para análise univariada e bivariada. A prevalência de excesso de peso encontrada para o Brasil foi de 34,2% (IC95% 33,8-34,6%). O excesso de peso apresentou autocorrelação espacial moderada (0,581; p = 0,01) e maiores prevalências nos estados das regiões Sul, Sudeste e Centro-Oeste. As prevalências de excesso de peso apresentaram correlação espacial positiva e moderada com o IDH (0,605; p< 0,05), proporção de aquisição domiciliar de produtos alimentícios ultraprocessados (0,559; p< 0,05); e correlação negativa e moderada com a prevalência de domicílios em insegurança alimentar (-0,561; p< 0,05). Conclui-se que a ocorrência de excesso de peso encontrava-se desigualmente distribuída no território brasileiro. As prevalências mais elevadas foram encontradas nos estados do Sudeste, Sul e Centro-Oeste, associadas a maiores valores de IDH e proporções de aquisição de produtos alimentícios ultraprocessados.
Abstract The aim of this study was to analyze the spatial distribution of excess weight in Brazil and its correlation with household food insecurity, purchase of foods by type of processing, and Human Development Index (HDI). An ecological study was undertaken using data from three surveys conducted by the Brazilian Institute of Geography and Statistics. Spatial analysis techniques were used to perform univariate and bivariate analysis. The prevalence of excess weight was 34.2% (CI 95% 33.8-34.6%). Excess weight showed a moderate and significant spatial autocorrelation (0.581; p = 0.01), with higher prevalence in states in the South, Southeast and Center-West regions. A positive moderate spatial correlation was shown between the prevalence of excess weight and HDI (0.605; p < 0.05) and purchase of ultra-processed foods (0.559; p < 0.05), while a negative moderate spatial correlation was observed between prevalence of excess weight and household food insecurity (-0.561; p < 0.05). It can be concluded that there is an unequal distribution of excess weight across Brazil. The highest prevalence rates were found in states in the Southeast, South, and Center-West regions, associated with higher HDI values and higher ultra-processed food purchases as a proportion of overall household food purchases.
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Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Adulto Jovem , Comportamento do Consumidor/estatística & dados numéricos , Sobrepeso/epidemiologia , Fast Foods/estatística & dados numéricos , Abastecimento de Alimentos/estatística & dados numéricos , Peso Corporal , Brasil/epidemiologia , Prevalência , Análise Espacial , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Temporal trends in dietary patterns reveal associations between food consumption and increased prevalence of non-communicable chronic disease. OBJECTIVES: This study characterized dietary patterns in adolescents in urban area located in northeast of Brazil, relating it to the markers of a healthy diet. METHODS: A cross-sectional study used two 24-hour recalls to assess dietary intake in 430 public school students from Natal-RN, Brazil. Principal component analysis was used to derive dietary patterns according to consumption of food based on weight (grams), energy (Kcal), or fiber (grams). The analysis results yielded 3 distinct principal components: 7, 8, and 4 (cumulative variance >70%; factor loadings >0.4). The association between independent variables and the factor scores of all components obtained was determined by the Prevalence Ratio (CI 95%). RESULTS: The dietary patterns derived were: (1) Pure Traditional Food System, the highly representative pattern in young adolescents and the first component of the analytical models, (2) Combined and Risk Food System; extraction of total food weight and energy revealed markers of unhealthy diets based on high sugar, saturated fat, and salt consumption, and (3) Modified Traditional Food System represented by fiber; pattern 1 was observed within this model too. The associations observed, predominantly from the TFSm pattern, distinguished by sex, age and nutritional status. CONCLUSIONS: Patterns 1 and 3 are characterized by preserved regional food practices that prevent chronic disease, whereas pattern 2 is characterized by health risks. These inter-sectorial findings should be considered in the development of health care policies for children and adolescents.
Introducción: Estudios nacionales de evolución temporal encuentran que la tendencia del consumo alimentario se asocia con aumento de la prevalencia de las enfermedades crónicas. Objetivos: Caracterizar los hábitos alimentarios de los adolescentes en un área urbana del Noreste de Brasil, relacionándolos con los marcadores dietéticos saludables. Métodos: Estudio transversal con adolescentes (n=430) de las escuelas públicas de Natal-RN, Brasil. El consumo alimentario se evaluó mediante dos recordatorios 24h. La técnica de Análisis de Componentes Principales fue utilizada para derivar patrones dietéticos, de acuerdo con: alimentos en gramos (g), la energía en Kcal y la fibra en gramos, lo que resulta, respectivamente, en 3 componentes principales distintos: 7, 8 y 4 (varianza acumulada >70%; cargas factoriales >0,4). La asociación entre las variables independientes y los escores de los factores de todos los componentes obtenidos, se determinó por la razón de prevalencia (IC 95%). Resultados: Los patrones dietéticos fueron: el (1) Sistema Alimentario Tradicional puro representó el primero componente de los modelos; el (2) Sistema Alimentario Combinado y de riesgo reveló marcadores de alimentación no saludables, debido a la alta frecuencia de azucares refinados, grasas saturadas y sal; y el (3) Sistema Alimentario Modificado fue identificado en el modelo de las fibras, el patrón 1 de nuevo fue observado en este patrón. Las asociaciones observadas, en particular del patrón SATm, distinguen por sexo, edad y estado nutricional. Conclusiones: Los patrones dietéticos 1 y 3 se caracterizaron por la preservación de las prácticas regionales de alimentos, muy saludables, desde el punto de vista de la prevención de las enfermedades crónicas, mientras que el 2 representó alerta y riesgo para la salud. Los hallazgos pueden subvencionar Políticas de Atención a la Salud para infancia y adolescencia en carácter intersectorial.
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Comportamento Alimentar , Adolescente , Brasil , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Estado Nutricional , População Urbana , Adulto JovemRESUMO
INTRODUCTION: In June 2009, the World Health Organization declared an influenza pandemic associated with the pandemic (H1N1) 2009 strain. It was summer in the northern hemisphere, and therefore travelling and vacation time, which also provided an increased opportunity for the dissemination of respiratory diseases. METHODOLOGY: We reviewed the paper case report forms from all the patients with influenza-like illnesses with nasopharyngeal samples submitted for laboratory diagnosis of pandemic (H1N1) 2009 infection during the first wave of pandemic influenza that occurred between June and August 2009, in the central region of Portugal. RESULTS: From all the patients with influenza-like illnesses, one third was found positive for pandemic (H1N1) 2009. Individuals under the age of 29 (75%) were the most affected. Most of the patients (91%) presented with fever. A group of symptoms were positively correlated with the probability of pandemic (H1N1) 2009 infection: cough, epistaxis, lack of dyspnea or vomiting, fever, headache and myalgia. CONCLUSIONS: During the first wave of the pandemic influenza, young individuals were the most affected, and in the ambulatory setting, presentation was of a mild febrile illness without complications.
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Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Febre , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pandemias , Portugal/epidemiologia , Fatores de Risco , Adulto JovemRESUMO
OBJECTIVE: The aim of this study was to describe the sources of dietary variance, and determine the variance ratios and the number of days needed for estimating the habitual diet of adolescents. METHODS: Two 24 hour food recalls were used for estimating the energy, macronutrient, fatty acid, fiber and cholesterol intakes of 366 adolescents attending Public Schools in Natal, Rio Grande do Norte, Brazil. The variance ratio between the intrapersonal and interpersonal variances, determined by Analysis of Variance, was calculated. The number of days needed for estimating the habitual intake of each nutrient was given by the hypothetical correlation (r)>0.9 between the actual and observed nutrient intakes. RESULTS: Sources of interpersonal variation were higher for all nutrients and in both genders. Variance ratios were <1 for all nutrients and higher in women. Two 24 hour dietary recalls were enough to assess energy, carbohydrate, fiber and saturated and monounsaturated fatty acid intakes accurately. However, the accurate assessment of protein, lipid, polyunsaturated fatty acid and cholesterol intakes required three 24 hour recalls. CONCLUSION: Interpersonal dietary variance in adolescents was greater than intrapersonal variance for all nutrients, resulting in a variance ratio of less than 1. Two to three 24 hour recalls, depending on gender and the study nutrient, are necessary for estimating the habitual diet of this population.
OBJETIVO: O objetivo deste estudo foi descrever as fontes de variância da dieta, determinar as razões de variâncias e o número de dias necessários para estimar a dieta habitual em adolescentes. MÉTODOS: A ingestão de energia, macronutrientes, ácidos graxos, fibra e colesterol foram estimadas por meio de dois recordatórios de 24 horas, aplicados em 366 adolescentes de escolas públicas de Natal, Rio Grande do Norte. A razão de variância foi calculada entre o componente da variância intrapessoal e interpessoal, determinada pela Análise de Variância. A definição do número de dias para a estimativa da ingestão habitual de cada nutriente foi obtida considerando a correlação hipotética de (r)>0,9, entre a verdadeira ingestão de nutrientes e a observada. RESULTADOS: As fontes de variância interpessoal foram maiores para todos os nutrientes e em ambos os sexos. As razões de variâncias foram <1 para todos os nutrientes, e mais elevadas no sexo feminino. Dois dias de recordatórios de 24 horas seriam suficientes para avaliar com precisão o consumo de energia, carboidratos, fibra, ácidos graxos saturados e monoinsaturados, exceto para proteínas, lipídeos, ácidos graxos poliinsaturados e o colesterol, que necessitariam de três dias. CONCLUSÃO: A variância interpessoal da dieta dos adolescentes foi maior do que a intrapessoal, para todos os nutrientes, repercutindo em uma razão de variância menor que 1. Para estimar a dieta habitual nesta população, uma variação de dois a três dias é necessária considerando o sexo e o nutriente avaliado.