BackgroundAcute exposure to ambient air pollution has been associated with acute changes in cardiac outcomes, often within hours of exposure.ObjectivesWe examined the effects of air pollutants on heart-rate–corrected QT interval (QTc), an electrocardiographic marker of ventricular repolarization, and whether these associations were modified by participant characteristics and genetic polymorphisms related to oxidative stress.MethodsWe studied repeated measurements of QTc on 580 men from the Veterans Affairs Normative Aging Study (NAS) using mixed-effects models with random intercepts. We fitted a quadratic constrained distributed lag model to estimate the cumulative effect on QTc of ambient air pollutants including fine particulate matter ≤ 2.5 μm in aerodynamic diameter (PM2.5), ozone (O3), black carbon (BC), nitrogen dioxide (NO2), carbon monoxide (CO), and sulfur dioxide (SO2) concentrations during the 10 hr before the visit. We genotyped polymorphisms related to oxidative stress and analyzed pollution–susceptibility score interactions using the genetic susceptibility score (GSS) method.ResultsAmbient traffic pollutant concentrations were related to longer QTc. An interquartile range (IQR) change in BC cumulative during the 10 hr before the visit was associated with increased QTc [1.89 msec change; 95% confidence interval (CI), −0.16 to 3.93]. We found a similar association with QTc for an IQR change in 1-hr BC that occurred 4 hr before the visit (2.54 msec change; 95% CI, 0.28–4.80). We found increased QTc for IQR changes in NO2 and CO, but the change was statistically insignificant. In contrast, we found no association between QTc and PM2.5, SO2, and O3. The association between QTc and BC was stronger among participants who were obese, who had diabetes, who were nonsmokers, or who had higher GSSs.ConclusionsTraffic-related pollutants may increase QTc among persons with diabetes, persons who are obese, and nonsmoking elderly individuals; the number of genetic variants related to oxidative stress increases this effect.

Background: The Philippines is facing a rapidly rising HIV epidemic among young men who have sex with men (MSM). Testing rates among young populations is poor. HIV self-testing (HIVST) is a promising strategy to address this testing gap. The study's purpose was to explore the perceived acceptability, feasibility and programmatic challenges of HIVST among key informants and target users. Method: A qualitative study involving semi-structured interviews and focus group discussions (FGD). We interviewed 15 key informants involved with HIV testing programs or policies and 42 target users in six FGD in Metro Manila. We held separate discussions with high socioeconomic MSM (n = 12), urban poor MSM (n = 15) and transgender women (TGW) (n = 15). Results were analysed using a thematic framework approach. Results: MSM and TGW welcomed the convenience and privacy HIVST could provide. They preferred an inexpensive accurate blood-based kit attained from reputable sites. Key informants at national and local level equally welcomed HIVST but identified a number of policy and regulatory issues. Both groups articulated the challenge of enrolling those who test reactive using HIVST to further testing and treatment in an environment characterised by acute stigma around HIV. Conclusions: HIVST was found to be highly acceptable to target users and was welcomed as an additional testing approach at national level. Strategic alliances are now needed between stakeholders to proactively deliver a patientcentred HIVST program that could provide an effective, safe means of increasing testing coverage in this escalating context.

BackgroundThe major causes of maternal and neonatal mortality in the Philippines are hemorrhages and obstructed labor due to placental implantation abnormalities (PIAs), twin pregnancies and fetal malpresentations. All of which are all easily detected by ultrasound. However, women in rural areas and low-income groups do not have access to ultrasound during their prenatal care. We aimed to provide additional evidence on the benefits of handheld ultrasound (HU) for screening pregnancy related abnormalities in order to avert maternal and neonatal deaths.MethodsUsing a HU, we trained community healthcare workers (CHWs) to identify 5 obstetrical conditions: fetal viability and number, placental localization, amniotic fluid volume (AFV) and fetal presentation. Women, between 20th and 24th weeks age of gestation from 2 regions of the Philippines, were scanned using the HU and the GE Logic 5 Premium ultrasound machine for validation. Maternal and neonatal deaths averted were estimated as health outcome measures of the study.ResultsFour hundred sixty women were scanned of which 146 (31.7%) showed abnormal ultrasound readings consisting of 17 PIAs, 123 fetal malpresentation, 3 twins and 3 AFV abnormalities. The use of HU could have possibly averted 29 (6.3%) maternal deaths and 14.6% neonatal deaths at the time of delivery. Thirty-two out of the 460 women (~7%) delivered at home and 93% in hospitals or birthing facilities/lying–in centers. We observed approximately 95% agreement between the ultrasound readings of the trainees and the trainers, and 99% agreement between the readings made from the HU with the validation machine.ConclusionCHWs could be trained in the use of HU for scanning 5 obstetrical parameters. Early detection of abnormalities in these 5 obstetrical parameters can lead to early referral to facilities that are better equipped to manage obstetrical emergencies. Prenatal ultrasound can be an excellent point of care test for screening pregnant women at risk for possible complications and even death during labor and delivery.Trial registrationThai Clinical Trial Registry identification number TCTR20171128004, retrospectively registered November 28, 2017.

High-level arsenic exposure is consistently associated with QT prolongation, a risk factor for arrhythmia and sudden cardiac death. Arsenic may act on QT by increasing cardiac calcium currents. The authors hypothesized that low-level arsenic exposure would be associated with QT duration and that this effect would be stronger among persons not using calcium channel blockers. They performed a cross-sectional analysis in elderly men from the Normative Aging Study to analyze associations between toenail arsenic and QT and heart rate-corrected QT (QTc) durations and to examine effect modification by calcium channel blocker use, using linear regression and adjusting for potential confounders. Participants were examined in Boston, Massachusetts, between 2000 and 2002 or in 2006. An interquartile range increase in arsenic concentration was associated with a 3.8-millisecond increase in QT (95% confidence interval: 0.82, 6.8) and a 2.5-millisecond increase in QTc (95% confidence interval: 0.11, 4.9). There was no evidence of effect modification by medication use for either QT (P = 0.93) or QTc (P = 0.58). The authors observed positive associations between a biomarker of arsenic exposure and QT duration but found no evidence of effect modification by calcium channel blocker use, possibly because of modest power.

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