Phenotyping Down syndrome: discovery and predictive modelling with electronic medical records.

BACKGROUND: Individuals with Down syndrome (DS) have a heightened risk for various co-occurring health conditions, including congenital heart disease (CHD). In this two-part study, electronic medical records (EMRs) were leveraged to examine co-occurring health conditions among individuals with DS (Study 1) and to investigate health conditions linked to surgical intervention among DS cases with CHD (Study 2). METHODS: De-identified EMRs were acquired from Vanderbilt University Medical Center and facilitated creating a cohort of N = 2282 DS cases (55% females), along with comparison groups for each study. In Study 1, DS cases were one-by-two sex and age matched with samples of case-controls and of individuals with other intellectual and developmental difficulties (IDDs). The phenome-disease association study (PheDAS) strategy was employed to reveal co-occurring health conditions in DS versus comparison groups, which were then ranked for how often they are discussed in relation to DS using the PubMed database and Novelty Finding Index. In Study 2, a subset of DS individuals with CHD [N = 1098 (48%)] were identified to create longitudinal data for N = 204 cases with surgical intervention (19%) versus 204 case-controls. Data were included in predictive models and assessed which model-based health conditions, when more prevalent, would increase the likelihood of surgical intervention. RESULTS: In Study 1, relative to case-controls and those with other IDDs, co-occurring health conditions among individuals with DS were confirmed to include heart failure, pulmonary heart disease, atrioventricular block, heart transplant/surgery and primary pulmonary hypertension (circulatory); hypothyroidism (endocrine/metabolic); and speech and language disorder and Alzheimer's disease (neurological/mental). Findings also revealed more versus less prevalent co-occurring health conditions in individuals with DS when comparing with those with other IDDs. Findings with high Novelty Finding Index were abnormal electrocardiogram, non-rheumatic aortic valve disorders and heart failure (circulatory); acid-base balance disorder (endocrine/metabolism); and abnormal blood chemistry (symptoms). In Study 2, the predictive models revealed that among individuals with DS and CHD, presence of health conditions such as congestive heart failure (circulatory), valvular heart disease and cardiac shunt (congenital), and pleural effusion and pulmonary collapse (respiratory) were associated with increased likelihood of surgical intervention. CONCLUSIONS: Research efforts using EMRs and rigorous statistical methods could shed light on the complexity in health profile among individuals with DS and other IDDs and motivate precision-care development.

Vitamin D receptor variants and uncontrolled asthma.

Summary: Background. Asthma is a common childhood respiratory disease, affecting around 20% of Irish children. In other populations, vitamin D receptor (VDR) polymorphisms have been associated with asthma risk. We aimed to investigate the association between 2 VDR polymorphisms and uncontrolled paediatric asthma. Methods. 44 asthmatic children and 57 healthy volunteers were studied. The VDR TaqI gene variant in exon 9 (T/C) (rs731236) and ApaI (rs7975232) in intron 8 (C/T) were determined, using TaqMan® Assays. The lung function, serum 25-hydroxyvitamin D (25OHD) levels and other biomarkers of allergy, immunity, airway and systemic inflammation were as-sessed. Results. The distribution of T and C alleles and genotype frequencies differed significantly between asthmatics and controls for both polymorphisms (p < 0.05). A significant association was found between both TaqI [OR = 2.37, 95% CI (1.27 - 4.45), p = 0.007] and ApaI polymorphisms, and asthma risk [OR = 2.93, 95% CI (1.62 - 5.3), p = 0.0004]. No association was observed between genotypes and 25OHD levels, lung function and other biomarkers, with the exception of Interleukin-10 (IL-10) and white blood cells count (WBC). IL-10 levels were lower in asthmatics with TC genotype for TaqI polymorphism (p < 0.01) and were higher in patients with TT genotype for ApaI (p < 0.01). WBC were higher in patients with TC and CC genotypes for TaqI (p < 0.05) and lower in TT genotype for ApaI (p < 0.05). Conclusion. TaqI and ApaI polymorphisms are associated with asthma in Irish children. Further studies are warranted to investigate the importance of decreased IL-10 levels in paediatric asthmatics with specific genotypes.

Nitrate-rich beetroot juice selectively lowers ambulatory pressures and LDL cholesterol in uncontrolled but not controlled hypertension: a pilot study.

BACKGROUND: Dietary nitrate has been shown to increase nitrate/nitrite levels in multiple populations, with potential blood pressure lowering effects. However, there are few reports among hypertensives. AIMS: We aimed to assess the effect of daily nitrate in subjects with controlled hypertension vs. uncontrolled hypertension. METHODS: On day 0, hypertensives wore an ambulatory BP monitor (ABPM) for 24 h and fasting blood was taken. Subjects then consumed concentrated beetroot juice (12.9 mmol nitrate) for 14 consecutive days. On day 14 subjects consumed their last nitrate dose after fasting blood was drawn and again had an ABPM for 24 h. RESULTS: According to baseline ABPM, 11 subjects had controlled BP while 8 had uncontrolled BP. There were similar, significant increases in serum nitrate/nitrite in both groups. We observed little change in BP variables among controlled hypertensives. However, there were reductions in BP variables in uncontrolled hypertensives where decreases in nighttime DBP (-6 ± 4.8 mmHg), arterial stiffness (-0.08 ± 0.03 ambulatory arterial stiffness index) and LDL (-0.36 ± 0.42 mmol/L) reached significance (p = 003, 0.05 and 0.046, respectively). CONCLUSIONS: Our results support the existing data suggesting an anti-hypertensive effect of nitrate-containing beetroot juice, but only among those with uncontrolled hypertension.

The Association Between 25 Hydroxyvitamin D and Airway Obstruction in Asthma.

Since Vitamin D has anti-inflammatory effects we wondered whether the association between low serum 25OHD and airway obstruction in moderate persistent asthma might be explained by inflammatory pathways that worsen asthma. All subjects examined were Irish Caucasians with moderate persistent asthma and none took systemic steroid therapy. In addition to computerized spirometry, we measured BMI, serum 25-hydroxyvitamin D (25OHD), total IgE, Eosinophil Cationic Protein (ECP), and high sensitive C- reactive protein (hs-CRP). One hundred (47 male) subjects completed the testing. Within single level of asthma severity, 25OHD levels were related to post-bronchodilator FEV1/FVC (r = 0.26, p< 0.01), but multiple linear regression analysis demonstrated that the association was not explained by obesity or inflammatory markers. We find a relationship exists between airway obstruction and 25OHD levels in asthmatic adults, and the effect is not explained by the presence of potential confounders such as obesity, allergy and systemic inflammation.