Investigating possible effects of aryl hydrocarbon receptor G1661A polymorphism on asthma severity in adults

Aryl hydrocarbon Receptor (AhR) is a ligand-activated transcription factor with an important role in lung health. The association of AhR polymorphisms with asthma severity has not been yet investigated. We analyzed the association of G1661A, the most prevalent polymorphism of AhR, with the asthma stages in a population-based study including 555 asthmatics (Intermittent: 93, Mild: 240, Moderate: 158, and Severe: 64). The SNP was genotyped using allele-specific PCR. Obtained data were analyzed using the Generalized-Ordered Logit Estimates. Genotypes GA (OR: 0.53, CI: 0.32-0.90, P=0.019) and AA (OR: 0.22, CI: 0.06-0.76, P=0.017) were associated with decreased risk of Severe, Moderate, Mild vs. Intermittent stage; and Severe, Moderate, vs. Mild, Intermittent stages respectively. However, Genotype GA (OR: 1.90, CI: 1.05-3.44, P=0.033), dominant model GA+AA (OR: 2.04, CI: 1.17-3.57, P=0.012), and allele A (OR: 1.68, CI: 1.06-2.66, P=0.027) were associated with increased risk of Severe stage vs. Moderate, Mild, Intermittent stages. Also, male sex and higher age were associated with an increased odds ratio for severe asthma. Furthermore, significant associations with asthma stages were found for the interactions of the SNP and sex, smoking, and alcohol consumption. In conclusion, we revealed that the mutant allele of AhR-G1661A may interact with independent variables and act as a protective factor against lower stages of asthma but it may increase the risk of severe asthma.

Polymorphism (-499C/G) in DDAH2 promoter may act as a protective factor for metabolic syndrome: A case-control study in Azar-Cohort population

ABSTRACT Objective: Globally developing metabolic syndrome (MetS) prevalence as a major health problem can be related to multiple factors of genetic and environmental. Dimethylaminohydrolase 2 (DDAH2) is the main enzyme implicated in the cardiovascular system, which regulates the nitric oxide pathway. This study investigated the association of DDAH2 polymorphism −499C/G (rs805305) with the risk of MetS among the Azar-Cohort population. Subjects and methods: The occurrence of SNP rs805305 in the DDAH2 gene was tested using the PCR-RFLP method in 332 MetS cases and 294 healthy controls. Afterward, the association of the allele and genotypes with the risk of MetS and its components were examined. Results: The G allele and GC genotype were significantly associated with a reduced risk of MetS (P ≤ 0.001). Also, the dominant genetic model (GG+GC) significantly decreased the risk of MetS (P = 0.001), however, in sex subtypes MetS risk was significantly reduced in males before and in females after adjustment for age (P ≤ 0.02). Conclusion: The −499C/G polymorphism of DDAH2 may play a protective role and reduce MetS risk among the Azar-Cohort population.

Obstructive sleep apnea syndrome: complaints and housing characteristics in a population in the United States / Sindrome de apneia obstrutiva do sono: queixas e caracteristicas da habitacao em uma populacao dos Estados Unidos da America

CONTEXT AND OBJECTIVE Obstructive sleep apnea syndrome (OSAS) is one of the leading causes of morbidity and mortality in adults. Early detection of the disorder and discovery of risk factors through standardized questionnaires will lead to reduction of the OSAS burden. The main aim of this study was to estimate the prevalence of OSAS symptoms and examine their association with housing characteristics. DESIGN AND SETTING Cross-sectional study at a medical school. METHODS Demographic, housing and body measurement data on 5,545 individuals aged 16 years and over of various races were selected from the National Health and Nutrition Examination Survey. We analyzed the probability of OSAS based on habitual snoring combined with daytime sleepiness and/or witnessed apnea. Univariate and multiple linear regression were used. RESULTS 9.8% of the men and 6.9% of the women reported symptoms suggestive of OSAS (habitual snoring, daytime sleepiness and/or apnea). The following prevalences of symptoms were found among males and females respectively: frequent snoring 35.1%, 22.3%, excessive daytime sleepiness 6.4%, 3.4% and frequent apnea 14.9%, 20.6%. Using multiple linear regression, OSAS symptoms were correlated with gender, age, body mass index (BMI), marital status and education. Regarding housing characteristics, mildew or musty smell and pets in the environment were associated with a high probability of OSAS. CONCLUSION OSAS symptoms were more prevalent than in developing countries. The environment was an important risk factor, but environmental factors are easier to control and manage than other variables like BMI or socioeconomic status. .

CONTEXTO E OBJETIVO Síndrome de apneia obstrutiva do sono (SAOS) é uma das principais causas de morbidade e mortalidade em adultos. Detecção precoce da doença e descoberta de fatores de risco com questionários padronizados levarão a redução dos danos por SAOS. O principal objetivo deste estudo foi estimar a prevalência de sintomas de SAOS e examinar sua associação com características da habitação. TIPO DE ESTUDO E LOCAL Estudo transversal em faculdade de medicina. MÉTODOS Dados demográficos, habitacionais e de medidas corporais sobre 5.545 indivíduos de 16 anos ou mais, de diversas raças, foram selecionados do National Health and Nutrition Examination Survey. Analisamos a probabilidade de SAOS com base no ronco habitual combinada com sonolência diurna e/ou apneia testemunhada. Análise univariada e regressão linear múltipla foram usadas. RESULTADOS 9,8% dos homens e 6,9% das mulheres relataram sintomas sugestivos de SAOS (ronco habitual, sonolência diurna e/ou apneia). A prevalência de sintomas em homens e mulheres, respectivamente, foi: ronco frequente 35,1%, 22,3%, sonolência excessiva diurna 6,4%, 3,4% e apneia frequente 14,9%, 20,6%. Através de regressão linear múltipla, sintomas de SAOS foram relacionados com gênero, idade, índice de massa corpórea (IMC), estado civil e educação. Das características da habitação, mofo ou cheiro de mofo e animais de estimação no ambiente foram associados com alta probabilidade de SAOS. CONCLUSÃO Sintomas de SAOS foram mais prevalentes do que nos países em desenvolvimento. O meio ambiente foi um fator de risco importante, porém é mais fácil controlar e manejar fatores ambientais do que outras variáveis, como IMC ou status socioeconômico. .