Using Wearable Biosensors to Predict Length of Stay for Patients with IBD After Bowel Surgery

Digestive Diseases and Sciences - It remains unknown whether ambulation or sleep predicts postoperative length of stay for patients with IBD. We aim to identify the utility of wearable biosensors...     

Clinical effects of antiplatelet drugs and statins on D‐dimer levels

Background

Acute pulmonary embolism may be ruled out by combining nonhigh clinical probability and a normal D‐dimer level. Both antiplatelet drugs and HMG‐CoA reductase inhibitors (statins) have been associated with effects on thrombus formation, potentially influencing D‐dimer levels in this setting, leading to a higher rate of false‐negative tests. Therefore, we determined whether D‐dimer levels in patients with suspected pulmonary embolism are affected by concomitant use of antiplatelet drugs and/or statins and evaluated whether the effect of antiplatelet drugs or statins might affect diagnostic accuracy.

Materials and methods

We performed a posthoc analysis in the YEARS diagnostic study, comparing age‐ and sex‐adjusted D‐dimer levels among users of antiplatelet drugs, statins and nonusers. We then reclassified patients within the YEARS algorithm by developing a model in which we adjusted D‐dimer cut‐offs for statin use and evaluated diagnostic accuracy.

Results

We included 156 statins users, 147 antiplatelet drugs users and 726 nonusers of either drugs, all with suspected pulmonary embolism . Use of antiplatelet drugs did not have a significant effect, whereas statin use was associated with 15% decrease in D‐dimer levels (95% CI, ?28% to ?0.6%). An algorithm with lower D‐dimer thresholds in statin users yielded lower specificity (0.42 compared to 0.33) with no difference in false‐negative tests.

Conclusions

We conclude that use of statins but not of antiplatelet agents is associated with a modest decrease in D‐dimer levels. Adjusting D‐dimer cut‐offs for statin use did, however, not result in a safer diagnostic strategy in our cohort.

     

Cognitive alterations in groups at risk for psychosis: neutral markers of genetic risk or indicators of social disability?

OBJECTIVE: To investigate whether cognitive alterations associated with vulnerability to psychosis, are associated with expression of psychopathology and functional outcome in groups at different levels of risk for psychotic illness. METHOD: Neurocognition, psychopathology and functional outcome were measured in subjects with variable risk for psychosis: i) 29 patients with psychotic disorder, ii) 46 subjects at familial risk, iii) 41 subjects at psychometric risk and iv) 54 control subjects. RESULTS: Dose-response relationships between cognitive dysfunction and increasing risk for psychosis were found. Cognitive alterations were predicted by negative symptoms in patients and by positive psychotic experiences in the familial risk group. In both at risk groups, cognitive speed was associated with functional outcome. CONCLUSION: Some cognitive impairments serve as neutral endophenotypic marker across the psychosis continuum. However, other cognitive alterations associated with transmission of psychosis may have a direct impact on the pathway from risk to psychopathology and alterations in functioning.     

Social cognition and neurocognition as independent domains in psychosis

Patients with psychosis display alterations in social cognition as well as in the realm of neurocognition. It is unclear, however, to what degree these cognitive domains represent two separate dimensions of liability or the pleiotropic expression of a single deficit. The purpose of the present study was to investigate (i) to what extent alterations in social cognition represent an independent area of vulnerability to psychosis, separate from neurocognitive deficits and (ii) whether social cognition is one construct or can be divided into several subcomponents. Five social cognition and three neurocognitive tasks were completed by 186 participants with different levels of vulnerability for psychosis: 44 patients with psychotic disorder; 47 subjects at familial risk; 41 subjects at psychometric risk and 54 control subjects. The social cognition tasks covered important basic subcomponents of social cognition, i.e. mentalisation (or theory of mind), data gathering bias (jumping to conclusions), source monitoring and attribution style. Neurocognitive tasks assessed speed of information processing, inhibition, cognitive shifting and strategy-driven retrieval from semantic memory. The results of factor analysis suggested that neurocognition and social cognition are two separate areas of vulnerability in psychosis. Furthermore, the social cognition measures lacked significant overlap, suggesting a multidimensional construct. Cognitive liabilities to psychosis are manifold, and include key processes underlying basic person-environment interactions in daily life, independent of cognition quantified by neuropsychological tests.     

Maternal inheritance of familial hypercholesterolemia caused by the V408M low-density lipoprotein receptor mutation increases mortality

Objective

Fetal exposure to maternal hypercholesterolemia increases the extent of fatty-streak formation in fetal aortas as well as the rate of progression, and may therefore increase coronary heart disease (CHD) risk later in life. We hypothesized that the risk of CHD in untreated individuals with familial hypercholesterolemia (FH) is more extreme when the disease is transmitted maternally.

Methods

In a large Dutch pedigree carrying the V408M mutation in the low-density lipoprotein (LDL) receptor gene, 161 individuals over seven generations were identified for which FH status and parent of origin of FH were known. We calculated standardized mortality ratios (SMR) and compared the consequences of maternal and paternal inheritance of FH by Poisson regression analysis.

Results

Maternally inherited FH was associated with significantly higher excess mortality than FH transmitted by fathers (relative risk 2.2; p = 0.048): the SMR of maternal inheritance was 2.49 (95% confidence interval (CI) 1.45–3.99; p = 0.001), whereas it was not significantly increased in paternally inherited FH (SMR 1.30, 95% CI 0.65–2.32; p = 0.234).

Conclusion

Mortality rates are more increased when FH is inherited through the mother, supporting the fetal origin of adulthood disease hypothesis with all cause death, the most indisputable outcome measure. Future research should explore safe options for cholesterol-lowering therapy of pregnant women with FH in order to prevent unfavourable (epigenetic) consequences leading to atherosclerosis in their children.     

fMRI item analysis in a theory of mind task

Conventional analyses of functional magnetic resonance imaging (fMRI) data compare the brain's response to stimulus categories (e.g., pictures of faces, stories about beliefs) across participants. In order to infer that effects observed with the specific items (a particular set of pictures or stories) are generalizable to the entire population (all faces, or all stories about beliefs), it is necessary to perform an "item analysis." Item analyses may also reveal relationships between secondary (non-hypothesized) features of the items and functional activity. Here, we perform an item analysis on a set of stories commonly used for localizing brain regions putatively involved in Theory of Mind (ToM): right and left temporo-parietal junction (RTPJ/LTPJ), precuneus (PC), superior temporal sulcus (STS) and medial prefrontal cortex (MPFC). We address the following questions: Do brain regions that comprise the ToM network respond reliably across items (i.e. different stories about beliefs)? Do these brain regions demonstrate reliable preferences for items within the category? Can we predict any region's response to individual items, by using other features of the stimuli? We find that the ToM network responds reliably to stories about beliefs, generalizing across items as well as subjects. In addition, several regions in the ToM network have reliable preferences for individual items. Linguistic features of the stimuli did not predict these item preferences.