A Machine Learning Approach Reveals Distinct Predictors of Vaping Dependence for Adolescent Daily and Non-Daily Vapers in the COVID-19 Era.

Since 2016, there has been a substantial rise in e-cigarette (vaping) dependence among young people. In this prospective cohort study, we aimed to identify the different predictors of vaping dependence over 3 months among adolescents who were baseline daily and non-daily vapers. We recruited ever-vaping Canadian residents aged 16-25 years on social media platforms and asked them to complete a baseline survey in November 2020. A validated vaping dependence score (0-23) summing up their responses to nine questions was calculated at the 3-month follow-up survey. Separate lasso regression models were developed to identify predictors of higher 3-month vaping dependence score among baseline daily and non-daily vapers. Of the 1172 participants, 643 (54.9%) were daily vapers with a mean age of 19.6 ± 2.6 years and 76.4% (n = 895) of them being female. The two models achieved adequate predictive performance. Place of last vape purchase, number of days a pod lasts, and the frequency of nicotine-containing vaping were the most important predictors for dependence among daily vapers, while race, sexual orientation and reporting treatment for heart disease were the most important predictors in non-daily vapers. These findings have implications for vaping control policies that target adolescents at different stages of vape use.

Differences in circadian variation in QT interval of the ECG in women compared to men.

BACKGROUND: Measurement of the QT interval in the ECG (QT interval) is important in evaluating risk for cardiac death and for assessing the impact of drugs on the heart. The objective of this study is to determine whether the time of day affects the QT interval, QT interval variability and whether these relationships are influenced by an individual's sex. METHODS: Twenty-four hour ECGs were analyzed in detail on 50 individuals, 49 years of age, without evidence of coronary artery disease, structural heart disease, or significant arrhythmias. Four different QT-heart rate adjustment formulae were calculated and compared. RESULTS: There were significant (P=0.0014) differences between the QT-heart rate relationship during three different time-periods (night 00:00 to 08:00 h, day 08:00 to 14:00 h and evening 14:00 to 24:00 h). Women, compared to men, had a steeper relation of QT to RR interval indicating that when heart rate slows at night, the QT interval is more prolonged which is consistent with a greater susceptibility to fatal arrhythmias. The variability of the QT interval (the SD) was significantly (P<0.01) greater in men than women at night and in the evening but not during the day. There were differences in the ability of different QT heart rate adjustment formulae to blunt the effect of heart rate changes on the QT interval during the day. CONCLUSION: The time of the day that the QT interval is assessed should be considered. The QT heart rate relationship is different in women than in men especially at night. QT interval variability is greater at night especially in men. There are differences in the ability of QT heart rate adjustment formulae to blunt the effect of heart rate on the QT interval. Differences in the QTc at night might be the basis for the higher prevalence of sudden death in women at night.

Iron deficiency and common neurodevelopmental disorders-A scoping review.

BACKGROUND: A wealth of human and experimental studies document a causal and aggravating role of iron deficiency in neurodevelopmental disorders. While pre-, peri-, and early postnatal iron deficiency sets the stage for the risk of developing neurodevelopmental disorders, iron deficiency acquired at later ages aggravates pre-existing neurodevelopmental disorders. Yet, the association of iron deficiency and neurodevelopmental disorders in childhood and adolescence has not yet been explored comprehensively. In this scoping review, we investigate 1) the association of iron deficiency in children and adolescents with the most frequent neurodevelopmental disorders, ADHD, ASD, and FASD, and 2) whether iron supplementation improves outcomes in these disorders. METHOD: Scoping review of studies published between 1994 and 2021 using "iron deficiency / iron deficiency anemia" AND "ADHD" OR "autism" OR "FASD" in four biomedical databases. The main inclusion criterion was that articles needed to have quantitative determination of iron status at any postnatal age with primary iron markers such as serum ferritin being reported in association with ADHD, ASD, or FASD. RESULTS: For ADHD, 22/30 studies and 4/4 systematic reviews showed an association of ADHD occurrence or severity with iron deficiency; 6/6 treatment studies including 2 randomized controlled trials demonstrated positive effects of iron supplementation. For ASD, 3/6 studies showed an association with iron deficiency, while 3/6 and 1/1 systematic literature review did not; 4 studies showed a variety of prevalence rates of iron deficiency in ASD populations; 1 randomized controlled trial found no positive effect of iron supplementation on behavioural symptoms of ASD. For FASD, 2/2 studies showed an association of iron deficiency with growth retardation in infants and children with prenatal alcohol exposure. CONCLUSION: Evidence in favor of screening for iron deficiency and using iron supplementation for pediatric neurodevelopmental disorders comes primarily from ADHD studies and needs to be further investigated for ASD and FASD. Further analysis of study methodologies employed and populations investigated is needed to compare studies against each other and further substantiate the evidence created.

Role of computed tomography (CT) in identifying foreign body ingestion in an individual with autism - A case report.

Foreign body ingestions are quite common and most often will uneventfully pass in stool, however, some ingestions, can lead to complications such as obstruction. If left untreated, this can lead to perforation and fistula formation. Hence, threshold for intervention should be low and diagnostic imaging can assist with treatment decisions. We present to you a case of 17-year-old male with non-verbal autism with an unusual hollow foreign body ingestion leading to small bowel obstruction.

Circadian variation of the QT interval and heart rate variability and their interrelationship.

BACKGROUND: Whether the QT interval displays circadian rhythm after heart rate correction is unresolved and the relationship of QT interval to heart rate variability (HRV) is uncertain. OBJECTIVES: To test the hypothesis that there is a circadian rhythm to QT interval and HRV and determine the relationship between QTc and HRV. METHODS: The hourly average ECG data from 24-h ECGs were examined in individuals (50 without medications and 9 on beta blockers only) with no evidence of coronary artery disease or structural heart disease. The QT duration of normal QRS complexes from a series of 30-s windows was measured. The presence of circadian rhythm was tested by the data analytic approach of goodness of fit to a cosine function. RESULTS: QT interval with and without heart rate correction showed a circadian rhythm for five heart rate adjustment formulae except for the Bazett formula. HRV also showed circadian rhythm but with different acrophages and nadirs depending on the HRV component. There were significant (p < 0.05) positive correlations of QTc with pNN50 rms-SD and SDNN and significant (p < 0.05) negative correlations with SDANN and Tri. The beta blocker group did not generally show circadian rhythm for QT interval or HRV. CONCLUSION: QT, after heart rate adjustment, and HRV have circadian rhythmicity. There are significant correlations between QT interval and HRV indices. Circadian rhythm was blunted with beta blockers. The data are consistent with the concept of a predominance of parasympathetic activity to increase QTc and sympathetic activity to shorten QTc, even after 'correction' of the QT interval for heart rate.

Iron deficiency and sleep - A scoping review.

Iron deficiency (ID) is associated with sleep disorders, but standardized assessment of iron status in the diagnostic work-up and iron supplementation as treatment have not been considered in clinical practice. We investigated associations of ID with type and severity of sleep disorders and whether iron supplementation improves sleep-related symptoms. In 2017, we conducted a scoping review for the period 1972-2016 using the terms "iron deficiency anemia" and "sleep" on biomedical database search engines, and in 2019, we updated our review with an ad-hoc search. Among the 93 articles meeting our inclusion criteria, 74/93 studies investigated restless legs syndrome (RLS), 8/93 periodic limb movements in sleep (PLMs), 3/93 sleep disordered breathing (SDB), 6/93 general sleep disturbances (GSD), and 2/93 attention-deficit/ hyperactivity disorder related sleep disorders (ADHD-SDs). A statistically supported positive association with ID was found in 22/42 RLS, 3/8 PLMs, 1/2 SDB, 3/4 GSD, and 1/2 ADHD-SDs association studies. The ad-hoc literature search revealed eight additional association studies with a statistically supported positive association in 2/5 RLS, 1/1 SDB, 1/1 ADHD-SDs, and 1/1 restless sleep disorder (RSD) studies. Iron supplementation was beneficial in 29/30 RLS (including five randomized controlled trials [RCTs]), 1/1 SDB, and 2/2 GSD treatment studies. Iron supplementation was also beneficial in 2/2 RLS (including two RCTs), 1/1 GSD (RCT), and 1/1 RSD studies identified in the ad-hoc search. In pediatric populations, 1/1 RLS, 1/1 SDB, 2/5 PLMs, 2/3 GSD and 1/2 ADHD-SDs studies found positive associations, and 6/6 RLS and 2/2 GSD studies demonstrated a benefit with iron supplementation. In conclusion, iron investigation and supplementation should be considered in patients presenting with sleep disorders. To investigate the role of ID in sleep in the future, a harmonization of study designs, including outcome measures and standardized iron and inflammation status is necessary.