Improvement in Specificity of [14C]d-Xylose Breath Test for Bacterial Overgrowth

The aim of the study was to determine whetherthe specificity of the [¹⁴C]d-xylose breathtest could be improved, by excluding false-positivetests due to premature colonic metabolism of the[¹⁴C]d-xylose caused by rapid colonictransit. Forty-seven patients with suspected small bowelbacterial overgrowth were investigated by (1) aspirationand culture of duodenal fluid and (2) a[¹⁴C]d-xylose breath test. Those with either a positiveduodenal culture or breath test had a repeat[¹⁴C]d-xylose breath test given with one ofthree transit markers (barium, Gastrografin or^99mTc-labeled tin colloid) to determine if the site of metabolism was inthe small bowel or colon. Fourteen patients had positiveduodenal cultures, four of whom had a negative[¹⁴C]d-xylose breath test, 15 patients had apositive [¹⁴C]d-xylose breath test, three ofwhich were due to colonic metabolism of the xylose.Where transit markers were used, ¹⁴C wasdetectable in the breath and serum before barium hadentered the small bowel, thus the barium did not comigrate withthe xylose. Gastrografin accelerated small boweltransit, leading to malabsorption of the xylose in thesmall intestine and subsequent colonic metabolism of the xylose. ^99mTc-labeled tincolloid had no obvious disadvantages and appeared to bethe marker of choice. The use of a transit markerincreased the specificity of the[¹⁴C]d-xylose breath test from 85% to 94%. The specificity of the[¹⁴C]d-xylose breath test for the detectionof small bowel bacterial overgrowth is improved togreater than 90% by the use of an appropriate transitmarker.     

Feasibility of determining myocardial infarction type from medical record review

BACKGROUND

Hospital discharge data are used extensively in health research. Given the clinical differences between ST segment elevation myocardial infarction (STEMI) and non-ST segment elevation myocardial infarction (NSTEMI), it is important that these entities be distinguishable in a medical record. The authors sought to determine the extent to which the type of MI is recorded in medical records, as well as the consistency of this designation within individual records.

METHODS

Records of all MI patients admitted to a tertiary care centre in Canada from April 1, 2000, to March 31, 2001, were reviewed. Documentation and consistency of the use of the terms STEMI (Q wave, ST elevation or transmural MI) or NSTEMI (non-Q wave, subendocardial or nontransmural MI) were assessed in the admission history, progress notes, coronary care unit summary and discharge summary sections of each record.

RESULTS

Missing data were common; each chart section mentioned MI type in fewer than one-half of charts. When information was combined, it was possible to determine the type of MI in 81.1% of cases. MI type was consistently described as STEMI in 48.7% of cases, and as NSTEMI in 32.4%. Of concern, MI type was discrepant across sections in 10.5% of cases and missing entirely in 8.4% of cases.

CONCLUSIONS

The designation of MI cases as STEMI or NSTEMI is both incomplete and inconsistent in hospital records. This has implications for health services research conducted retrospectively using medical record data, because it is difficult to comprehensively study processes and outcomes of MI care if the type cannot be retrospectively determined.     

Chromosome 15q25.1 genetic markers associated with level of response to alcohol in humans

As with other genetically complex common psychiatric and medical conditions, multiple genetic and environmental components contribute to alcohol use disorders (AUDs), which can confound attempts to identify genetic components. Intermediate phenotypes are often more closely correlated with underlying biology and have often proven invaluable in genetic studies. Level of response (LR) to alcohol is an intermediate phenotype for AUDs, and individuals with a low LR are at increased risk. A high rate of concurrent alcohol and nicotine use and dependence suggests that these conditions may share biochemical and genetic mechanisms. Genetic association studies indicate that a genetic locus, which includes the CHRNA5-CHRNA3-CHRNB4 gene cluster, plays a role in nicotine consumption and dependence. Genetic association with alcohol dependence was also recently shown. We show here that two of the markers from the nicotine studies also show an association (multiple testing corrected P < 0.025) with several LR phenotypes in a sample of 367 siblings. Additional markers in the region were analyzed and shown to be located in a 250-kb expanse of high linkage disequilibrium containing three additional genes. These findings indicate that LR intermediate phenotypes have utility in genetic approaches to AUDs and will prove valuable in the identification of other genetic loci conferring susceptibility to AUDs.     

Using the Coriell Personalized Medicine Collaborative Data to conduct a genome‐wide association study of sleep duration

Sleep is critical to health and functionality, and several studies have investigated the inherited component of insomnia and other sleep disorders using genome‐wide association studies (GWAS). However, genome‐wide studies focused on sleep duration are less common. Here, we used data from participants in the Coriell Personalized Medicine Collaborative (CPMC) (n = 4,401) to examine putative associations between self‐reported sleep duration, demographic and lifestyle variables, and genome‐wide single nucleotide polymorphism (SNP) data to better understand genetic contributions to variation in sleep duration. We employed stepwise ordered logistic regression to select our model and retained the following predictive variables: age, gender, weight, physical activity, physical activity at work, smoking status, alcohol consumption, ethnicity, and ancestry (as measured by principal components analysis) in our association testing. Several of our strongest candidate genes were previously identified in GWAS related to sleep duration (TSHZ2, ABCC9, FBXO15) and narcolepsy (NFATC2, SALL4). In addition, we have identified novel candidate genes for involvement in sleep duration including SORCS1 and ELOVL2. Our results demonstrate that the self‐reported data collected through the CPMC are robust, and our genome‐wide association analysis has identified novel candidate genes involved in sleep duration. More generally, this study contributes to a better understanding of the complexity of human sleep. © 2015 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics Published by Wiley Periodicals, Inc.     

Applying the Verona coding definitions of emotional sequences (VR-CoDES) in the dental context involving patients with complex communication needs: An exploratory study

Objective

The VR-CoDES has been previously applied in the dental context. However, we know little about how dental patients with intellectual disabilities (ID) and complex communication needs express their emotional distress during dental visits. This is the first study explored the applicability of the VR-CoDES to a dental context involving patients with ID.

Methods

Fourteen dental consultations were video recorded and coded using the VR-CoDES, assisted with the additional guidelines for the VR-CoDES in a dental context. Both inter- and intra-coder reliabilities were checked on the seven consultations where cues were observed.

Results

Sixteen cues (eight non-verbal) were identified within seven of the 14 consultations. Twenty responses were observed (12 reducing space) with four multiple responses. Cohen's Kappa were 0.76 (inter-coder) and 0.88 (intra-coder).

Conclusion

With the additional guidelines, cues and responses were reliably identified. Cue expression was exhibited by non-verbal expression of emotion with people with ID in the literature. Further guidance is needed to improve the coding accuracy on multiple providers’ responses and to investigate potential impacts of conflicting responses on patients.

Practice implications

The findings provided a useful initial step towards an ongoing exploration of how healthcare providers identify and manage emotional distress of patients with ID.