Introduction: Primary liver cancer is a significant cause of cancer-related death in both the United States and the world at large. Hepatocellular carcinoma comprises 90% of these primary liver cancers and has numerous known etiologies. Evaluation of these identified etiologies and other traditional risk factors cannot explain the high incidence rates of hepatocellular carcinoma in Texas. Texas is home to the second largest petrochemical industry and agricultural industry in the nation; industrial activity and exposure to pathogenic chemicals have never been assessed as potential links to the state's increased incidence rate of hepatocellular carcinoma. Methods: The association between the county-level concentrations of 4 air pollutants known to be linked to liver cancer, vinyl chloride, arsenic, benzene, and 1,3-butadiene, and hepatocellular carcinoma rates was evaluated using nonparametric generalized additive logistic regression and gamma regression models. Hepatocellular carcinoma incidence rates for 2000-2013 were evaluated in comparison to 1996 and 1999 pollution concentrations and hepatocellular carcinoma rates for the subset of 2006-2013 were evaluated in comparison to 2002 and 2005 pollution concentrations, respectively. Results: The analysis indicates that the relationship between the incidence of liver cancer and air pollution and risk factors is nonlinear. There is a consistent significant positive association between the incidence of liver cancer and hepatitis C prevalence rates (gamma all years, p < 0.05) and vinyl chloride concentrations (logistic 2002 and 2005, p < 0.0001; gamma 2002 and 2005, p < 0.05). Conclusions: This study suggests that vinyl chloride is a significant contributor to the incidence of liver cancer in Texas. The relationship is notably nonlinear. Further, the study supports the association between incidence of liver cancer and prevalence of hepatitis B.

Interventions to prevent asthma emergencies should be targeted in the high rate area and towards groups identified most at risk. Consideration should be given to improved access to care after normal doctor office hours in these locations. While ambulance treatment reflects the most urgent care needs, these interventions are also expected to reduce the need for emergency room visits.

Introduction: This study presents a framework for identifying "high-risk" days for asthma attacks associated with elevated concentrations of criteria pollutants using local information to warn citizens on days when the concentrations differ from Environmental Protection Agency Air Quality Index (AQI) warnings. Studies that consider the unique mixture of pollutants and the health data specific to a city provide additional information for asthma self-management. This framework is applied to air pollution and asthma data to identify supplemental warning days in Houston, Texas. Methods: A four-step framework was established to identify days with pollutant levels that pose meaningful increased risk for asthma attacks compared with baseline. Historical associations between 18,542 ambulance-treated asthma attacks and air pollutant concentrations in Houston, Texas (2004−2016; analyzed in 2018), were analyzed using a case-crossover study design with conditional logistic regression. Days with historically high associations between pollution and asthma attacks were identified as supplemental warning days. Results: Days with 8-hour maximum ozone >66.6 parts per billion for the 3 previous days and same-day 24-hour nitrogen dioxide >19.3 parts per billion pose an RR of 15% above baseline; concentrations above these levels pose an increased risk of 15% (RR=1.15, 95% CI=1.14, 1.16) and 30% (RR=1.30, 95% CI=1.29, 1.32), respectively. These warnings add an additional 12% days per year over the AQI warnings. Conclusions: Houston uses this framework to identify supplemental air quality warnings to improve asthma self-management. Supplemental days reflect risk lower than the National Ambient Air Quality Standards and consecutive poor air quality days, differing from the AQI.

Context: Houston policy is to dual dispatch medically trained firefighters, in addition to emergency medical services (EMS) units to out-of-hospital cardiac arrest (OHCA) cases. While believed to improve public health outcomes, no research exists supporting the policy that when firefighters respond before a better-equipped EMS unit, they increase the probability of survival. Objective: To inform EMS policy decisions regarding the effectiveness of dual dispatch by determining the impact of medically trained firefighter dispatch on return of spontaneous circulation (ROSC), a measure of survivability, in OHCA 911 calls while controlling for the subsequent arrival of an EMS unit. Design: This retrospective study uses logistic regression to determine the association between ROSC and response time for fire apparatus first responders controlling for arrival of the EMS unit. Setting: Out-of-hospital cardiac arrest cases in Houston between May 2008 and April 2013 when dual dispatch was used. Participants: A total of 6961 OHCA cases with the complete data needed for the analysis. Main Outcome Measures: Logistic regression of the dependence of OHCA survival using the indicator ROSC, as related to the fire first responder response times controlling for subsequent arrival of the EMS. Results: Fire apparatus arrived first in 46.7% of cases, a median value of 1.5 minutes before an EMS unit. Controlling for subsequent arrival time of EMS has no effect on ROSC achieved by the fire first responder. If the firefighters had not responded, the resulting 1.5-minute increase in response time equates to a decrease in probability of attaining ROSC of 20.1% for cases regardless of presenting heart rhythm and a 47.7% decrease for ventricular fibrillation cases in which bystander cardiopulmonary resuscitation was initiated. Conclusions: The firefighter first responder not only improved response time but also greatly increased survivability independent of the arrival time of the better-equipped EMS unit, validating the public health benefit of the dual dispatch policy in Houston.