Predicting cardiovascular disease risk using photoplethysmography and deep learning.

Cardiovascular diseases (CVDs) are responsible for a large proportion of premature deaths in low- and middle-income countries. Early CVD detection and intervention is critical in these populations, yet many existing CVD risk scores require a physical examination or lab measurements, which can be challenging in such health systems due to limited accessibility. We investigated the potential to use photoplethysmography (PPG), a sensing technology available on most smartphones that can potentially enable large-scale screening at low cost, for CVD risk prediction. We developed a deep learning PPG-based CVD risk score (DLS) to predict the probability of having major adverse cardiovascular events (MACE: non-fatal myocardial infarction, stroke, and cardiovascular death) within ten years, given only age, sex, smoking status and PPG as predictors. We compare the DLS with the office-based refit-WHO score, which adopts the shared predictors from WHO and Globorisk scores (age, sex, smoking status, height, weight and systolic blood pressure) but refitted on the UK Biobank (UKB) cohort. All models were trained on a development dataset (141,509 participants) and evaluated on a geographically separate test (54,856 participants) dataset, both from UKB. DLS's C-statistic (71.1%, 95% CI 69.9-72.4) is non-inferior to office-based refit-WHO score (70.9%, 95% CI 69.7-72.2; non-inferiority margin of 2.5%, p<0.01) in the test dataset. The calibration of the DLS is satisfactory, with a 1.8% mean absolute calibration error. Adding DLS features to the office-based score increases the C-statistic by 1.0% (95% CI 0.6-1.4). DLS predicts ten-year MACE risk comparable with the office-based refit-WHO score. Interpretability analyses suggest that the DLS-extracted features are related to PPG waveform morphology and are independent of heart rate. Our study provides a proof-of-concept and suggests the potential of a PPG-based approach strategies for community-based primary prevention in resource-limited regions.

The methylome and cell-free DNA: current applications in medicine and pediatric disease.

DNA methylation is an epigenetic mechanism that contributes to cell regulation and development, and different methylation patterns allow for the identification of cell and tissue type. Cell-free DNA (cfDNA) is composed of small circulating fragments of DNA found in plasma and urine. Total cfDNA levels correlate with the presence of inflammation and tissue injury in a variety of disease states. Unfortunately, the utility of cfDNA is limited by its lack of tissue or cell-type specificity. However, methylome analysis of cfDNA allows the identification of the tissue or cell type from which cfDNA originated. Thus, methylation patterns in cfDNA from tissues isolated from direct study may provide windows into health and disease states, thereby serving as a "liquid biopsy". This review will discuss methylation and its role in establishing cellular identity, cfDNA as a biomarker and its pathophysiologic role in the inflammatory process, and the ways cfDNA and methylomics can be jointly applied in medicine. IMPACT: Cell-free DNA (cfDNA) is increasingly being used as a noninvasive diagnostic and disease-monitoring tool in pediatric medicine. However, the lack of specificity of cfDNA limits its utility. Identification of cell type-specific methylation signatures can help overcome the limited specificity of cfDNA. As knowledge of the cfDNA methylome improves, cfDNA will be more broadly applied in medicine, such that clinicians will need to understand the methods and applications of its use.

Virtual Reality after Surgery-A Method to Decrease Pain After Surgery in Pediatric Patients.

BACKGROUND: Virtual Reality (VR) is used as an effective tool for distraction and as an adjunct for pain management. This study was conducted to compare VR to standard iPad use after surgery and examine its effect on pain score and opioid consumption. METHODS: This was a randomized controlled study, with stratification by surgery type, age group (7-12yo, 13-18yo) and gender. Pain and anxiety were assessed with validated scales (STAI, FACES, VAS, FLACC) and outcomes were compared between each group. RESULTS: 50 of the 106 enrolled patients used the VR device. After adjusting for age, gender, and STAI, patients had a decreased FLACC score while using the VR device compared to the iPad group (odds ratio 2.95, P = .021). The younger patients were found to have lower FLACC scores while using the VR device (odds ratio 1.15, p=0.044); this finding was most significant when patients used the VR device for 20-30 minutes (odds ratio 1.67, P = .0003). Additionally, after adjusting for treatment group, gender, and STAI, the younger patients had higher odds of withdrawal or exclusion from the study (odds ratio 1.18, P = .021). No significant difference in opioid consumption between the groups was found. DISCUSSION: Virtual reality was well tolerated and more effective in decreasing pain during the immediate postoperative period than iPad use. Despite a slightly higher withdrawal rate, younger patients benefited more from the intervention.

Tracking neonicotinoids following their use as cotton seed treatments.

Neonicotinoids are a leading class of insecticides on the global market, accounting for nearly 25%. They are widely used in both agricultural and residential settings. Causing neuron failure by irreversibly binding to the insect nicotinic acetylcholine receptor, neonicotinoids offer broad spectrum efficacy against a variety of pests. However, because they are non-selective with regard to insect species, there has been some concern with neonicotinoid use over threats to pollinators such as honeybees, and potential indirect effects to migratory waterfowl as a result of invertebrate prey population depletion. In order to study occurrence and fate of neonicotinoids (thiamethoxam and imidacloprid), we analyzed cotton leaves on plants grown from neonicotinoid-treated seeds and corresponding soil samples between cotton rows. Neonicotinoid concentration data from cotton leaves appears to be consistent with the claim that seed treatments protect plants for 3-4 weeks; by 30 days post-planting, neonicotinoid concentrations fell, in general, to 200 ng/g or lower. This represents about a 10-fold decrease from plant concentrations at approximately 2 weeks post-planting. It was found that neonicotinoids used as seed treatments remained present in the soil for months post planting and could be available for runoff. To that end, 21 playa wetlands were sampled; 10 had at least one quantifiable neonicotinoid present, three of which were classified as grassland or rangeland playas, two were urban, and the remaining five were cropland playas. In several instances, neonicotinoid concentrations in playas exceeded EPA chronic benchmarks for aquatic invertebrates.

Soda Consumption Among Methamphetamine Users in the USA: Impact on Oral Health.

PURPOSE: Dental disease is associated with methamphetamine (MA) use and partly attributed to excessive consumption of sugared sodas. Hence, the purpose of this study was to verify patterns of sugared soda intake and their relationship to oral health. MATERIALS AND METHODS: Detailed assessments with 541 MA users at two dental clinics were conducted. Assessment included a lifetime history of methamphetamine use, sugared soda consumption and a dental exam. RESULTS: Subjects were predominantly male (80.8%; mean age 44.4 years), on average had used MA for 11.6 years and drank an average of 35.3 sodas per month. Number of days of MA use over the past 30 days was significantly associated with soda consumption. Increased years of MA use was associated with the likelihood of users reporting less overall satisfaction with life because of their teeth, specifically difficulty eating, and dry mouth. This is the first study to show a statistically significant association between MA use and sugared soda consumption. CONCLUSIONS: MA users' consumption of sugared sodas is higher than in the adult general population, and this is the first study to show a statistically significant association between MA use and sugared soda consumption. In addition, increased soda consumption was associated with more dental problems among MA users.

A Comparison of Methamphetamine Users to a Matched NHANES Cohort: Propensity Score Analyses for Oral Health Care and Dental Service Need.

Dental problems are among the most frequently reported health issues of drug users. This study describes, among the largest population of methamphetamine (MA) users to date (N = 459, including both HIV-negative and HIV-positive participants) oral hygiene practice, dental care access, and dental quality of life. A matched control group from the Third National Health and Nutrition Examination Survey was utilized. Findings conclusively establish that MA users have severe oral health deficits compared to the general population: they are 3.5 times more likely to experience painful toothaches, 6.6 times to experience difficulty eating, and 8.6 times to be self-conscious due to dental appearance. HIV-positive users were more likely to have regular dental visits than HIV-negative users. Severity of use (both high-frequency use as well as injection as the method) was associated with poorer oral health care. Despite the magnitude of the need, few MA users receive the needed care.

Dental disease patterns in methamphetamine users: Findings in a large urban sample.

BACKGROUND: The authors used a large community sample of methamphetamine (MA) users to verify the patterns and severity of dental disease and establish a hierarchy of caries susceptibility by tooth type and tooth surface. METHODS: Using a stratified sampling approach, 571 MA users received comprehensive oral examinations and psychosocial assessments. Three calibrated dentists characterized dental and periodontal disease by using National Health and Nutrition Examination Survey protocols. The authors also collected data on substance use history and other attributes linked to dental disease. RESULTS: On all dental outcome measures, MA users evidenced high dental and periodontal disease, with older (≥ 30 years) and moderate or heavy MA users disproportionately affected. Women had higher rates of tooth loss and caries, as well as a greater prevalence of anterior caries. Current cigarette smokers were more likely to manifest 5 or more anterior surfaces with untreated caries and 3 or more teeth with root caries. Nearly 3% were edentulous, and a significant percentage (40%) indicated embarrassment with their dental appearance. CONCLUSIONS: MA users have high rates of dental and periodontal disease and manifest a dose-response relationship, with greater levels of MA use associated with higher rates of dental disease. Women and current cigarette smokers are affected disproportionately. The intraoral patterns and hierarchy of caries susceptibility in MA users are distinctive. PRACTICAL IMPLICATIONS: The prevalence and patterns of dental and periodontal disease could be used to alert dentists to possible covert MA use and to plan treatment. Concerns about dental appearance have potential as triggers for behavioral interventions.

Performance of a quality assurance program for assessing dental health in methamphetamine users.

BACKGROUND: Systematic characterization of the dental consequences of methamphetamine (MA) abuse presupposes a rigorous quality assurance (QA) program to ensure the credibility of the data collected and the scientific integrity and validity of the clinical study. In this report we describe and evaluate the performance of a quality assurance program implemented in a large cross-sectional study of the dental consequences of MA use. METHODS: A large community sample of MA users was recruited over a 30 month period during 2011-13 and received comprehensive oral examinations and psychosocial assessments by site examiners based at two large community health centers in Los Angeles. National Health and Nutrition Examination Survey (NHANES) protocols for oral health assessments were utilized to characterize dental disease. Using NHANES oral health quality assurance guidelines, examiner reliability statistics such as Cohen's Kappa coefficients and inter-class correlation coefficients were calculated to assess the magnitude of agreement between the site examiners and a reference examiner to ensure conformance and comparability with NHANES practices. RESULTS: Approximately 9% (n = 49) of the enrolled 574 MA users received a repeat dental caries and periodontal examination conducted by the reference examiner. There was high concordance between the reference examiner and the site examiners for identification of untreated dental disease (Kappa statistic values: 0.57-0.75, percent agreement 83-88%). For identification of untreated caries on at least 5 surfaces of anterior teeth, the Kappas ranged from 0.77 to 0.87, and percent agreement from 94 to 97%. The intra-class coefficients (ICCs) ranged from 0.87 to 89 for attachment loss across all periodontal sites assessed and the ICCs ranged from 0.79 to 0.81 for pocket depth. For overall gingival recession, the ICCs ranged from 0.88 to 0.91. When Kappa was calculated based on the CDC/AAP case definitions for severe periodontitis, inter-examiner reliability for site examiners was low (Kappa 0.27-0.67). CONCLUSION: Overall, the quality assurance program confirmed the procedural adherence of the quality of the data collected on the distribution of dental caries and periodontal disease in MA-users. Examiner concordance was higher for dental caries but lower for specific periodontal assessments.

Saliva sampling method affects performance of a salivary α-amylase biosensor.

OBJECTIVES: Prompted by the discordance between a standardized salivary alpha-amylase (sAA) biosensor applied in clinical settings and a reference laboratory analyzer, we examined the impact of the saliva sampling method on the analytic performance of the biosensor. METHODS: Direct mouth readings using the biosensor from 31 normal, healthy volunteers were compared to biosensor and conventional assay readings obtained from saliva samples collected concurrently by passive drool and processed in three different ways (unprocessed, thawed, and thawed and centrifuged). RESULTS: The direct readings from the mouth showed consistently lower sAA values (Ps < 0.01) compared to all other combinations of sample processing and quantification platforms (biosensor vs. conventional assay). Readings obtained from passive drool saliva were strongly correlated with one another, and Bland-Altman plots of agreement indicated a smaller discrepancy between conventional and biosensor readings obtained with passive drool when compared to the direct mouth readings. CONCLUSIONS: Our study indicates that the analytical performance of the sAA biosensor is influenced significantly by the saliva sampling method. In contrast to the relatively imprecise direct mouth measurements, biosensor sAA levels established indirectly from passive drool saliva samples provide more accurate estimation of sAA levels, even after intermediary processing steps (e.g., freezing, thawing, centrifugation).

Feasibility of recruiting peer educators for an online social networking-based health intervention.

OBJECTIVE: This study aims to determine the feasibility of recruiting peer leaders to deliver a community-based health intervention using social media. METHOD: We recruited sixteen African American and Latino men who have sex with men (MSM) as peer leaders for either an HIV prevention or general health intervention using social media. Inclusion criteria required that peer leaders were African American or Latino MSM health communication experts experienced using social media. To receive certification, peer leaders attended 3 training sessions on using social media for public health. Questionnaires asking about health knowledge and comfort using social media to discuss health-related topics were provided at baseline and post-training to ensure that peer leaders were qualified post-training. Repeated measures ANOVA models and χ2 tests tested for differences in peer leader knowledge and comfort using social media pre- and post-training. RESULTS: After training, peer leaders were significantly more comfortable using social media to discuss sexual positions. There were no significant differences pre- and post-training on other comfort or knowledge measures, as at baseline, almost all peer leaders were already comfortable using social media. CONCLUSION: Results suggest that peer leaders can be recruited who are qualified to conduct health interventions without needing additional training. The discussed training plan can further ensure that any unqualified peer leaders will be prepared after training. To our knowledge, this is the first study to suggest that peer leaders can be recruited as peer health educators to communicate using social media.

Utility of a salivary biosensor for objective assessment of surgery-related stress.

PURPOSE: To evaluate the clinical utility of a salivary α-amylase (sAA) biosensor for assessing oral surgery-related stress responses and the differential effect of the personality trait of pain catastrophizing. PATIENTS AND METHODS: A prospective cohort study was conducted in 76 healthy subjects who underwent elective removal of their third molars. Along with subjects' self-reports of anxiety and pain, biosensor-facilitated measurements of sAA levels were obtained at multiple time points during the preoperative consult, surgery, and postsurgical follow-up visits. In addition, subjects completed the Pain Catastrophizing Scale at baseline. Mixed-effect regression models examined changes in sAA levels and self-report ratings within and across visits and the contribution of pain catastrophizing. RESULTS: The sAA levels were lower during surgery and postsurgical follow-up compared with the consult visit (P < .01). The sAA levels decreased during the surgery visit (P < .05) and did not change during the consult or follow-up visits. Individuals who reported greater helplessness to pain manifested higher sAA levels during the surgery visit (P < .05). Self-reported anxiety ratings were highest during the surgery visit, and pain ratings were highest during the follow-up visit. CONCLUSIONS: The sAA levels did not show the predicted increases during the surgery visit compared with the consult and postsurgical follow-up visits or increases during the surgery visit. However, individuals who reported responding to pain with helplessness had higher sAA levels in anticipation of surgery, providing proof of concept for the value of point-of-care assessments of surgery-induced stresses and the differential effect of personality traits.