The association of environmental, meteorological, and pollen count variables with asthma-related emergency department visits and hospitalizations in the Bronx.

Objective: To better understand how meteorological variables, air quality variables, and pollen counts collectively contribute to asthma-related emergency department visits (AREDV) and asthma-related hospitalizations (ARH) among pediatric and adult patients in the New York City borough of the Bronx. Methods: The numbers of daily adult and pediatric AREDV and ARH from 2001 to 2008 were obtained from three Bronx hospitals. After removing outliers, interpolating missing data, and standardizing variable values by scaling the data using z-scores, data were analyzed using Spearman rank tests and linear regression models for the full year and each season. Results: There were a total of 42,065 AREDV and 1,664 ARH at both Bronx hospitals. With the exception of a spring peak in AREDVs, AREDVs and ARHs follow a cyclical pattern, climbing in the fall, plateauing in the winter, dropping in the spring, and reaching a low in the summer. Among the 11 air quality, meteorological, and pollen count variables, temperature and tree pollen made the greatest contribution to AREDV with scaled coefficients of -0.337 and 0.311 respectively; equating to an additional AREDV for every 5.0-unit decrease in temperature and an additional AREDV for every 186.0-unit increase in tree pollen. These two variables were confirmed to have independent associations with AREDV prior to the data interpolation. Grass pollen was also found to have a relatively large contribution to AREDV during the summer with a scaled coefficient of 0.314, equating to an additional AREDV for every 2.3-unit increase in grass pollen. Conclusion: There are distinct peaks of increased AREDVs that are closely associated with increased tree pollen counts in the spring and decreasing temperatures in the fall. Early anticipation of these air quality, meteorological, and pollen factor changes based on ongoing surveillance could potentially guide clinical practice and minimize AREDVs in the Bronx.

The association between pollutant levels and asthma-related emergency department visits in the Bronx after the World Trade Center attacks.

Objective: To examine the potential impact of the World Trade Center (WTC) attacks on asthma-related emergency department visits (AREDV) in the New York City borough of the Bronx. Methods: We obtained daily nitrogen dioxide (NO2), sulfur dioxide (SO2) and ozone (O3) values from the National Climatic Data Center's collection station in the Bronx from 1999 and 2002, a year before and after the WTC attacks. We compared daily AREDV and pollutant levels between 1999 and 2002 using the Wilcoxon signed rank sum test. We considered each season separately due to seasonal variations of AREDV and pollutants. We then used multiple linear regression models to assess the relationships between the changes in AREDV and the changes in pollutants from 1999 to 2002 in each season. Results: There were statistically significant increases from 1999 to 2002 in the daily NO2 in the summer. Significant increases for daily SO2 and O3 values from 1999 to 2002 occurred in all seasons. Significant increases occurred in daily AREDV values in the spring and fall. Multiple linear regression analyses showed that increases in the daily O3 values were significantly associated with increases in AREDV from 1999 to 2002 in the summer season. Conclusion: We observed a possible association between the WTC attacks and significant increases in O3 and SO2 for all seasons, and NO2 for the summer. AREDV significantly increased following the WTC attacks. Increases in daily O3 values were significantly associated with increases in AREDV in the summer season.

The association between asthma-related emergency department visits and pollen and mold spore concentrations in the Bronx, 2001-2008.

BACKGROUND: The incidence of asthma morbidity and mortality is highest among minority inner-city populations. Among New York City's five boroughs, the Bronx has the highest rate of asthma-related hospitalizations and mortality. Outdoor air pollutants have been associated with increased asthma-related ED visits (AREDV) in this borough. OBJECTIVE: To better understand the contribution of pollen and mold to asthma severity in the Bronx. METHODS: The numbers of daily adult and pediatric AREDV and asthma-related hospitalizations (ARH) from 2001 to 2008 were obtained from two Bronx hospitals. AREDV and ARH data were acquired retrospectively through the Clinical Looking Glass data analysis software. Daily counts for tree, grass and weed pollen and mold spore counts from March 2001 to October 2008 were obtained from the Armonk counting station. All data were statistically analyzed and graphed as daily values. RESULTS: There were a total of 42 065 AREDV and 10 132 ARH at both Bronx hospitals. There were spring and winter peaks of increased AREDV. Tree pollen counts significantly correlated with total AREDV (rho = 0.3639, p < 0.001), and pediatric (rho = 0.33, p < 0.001) and adult AREDV (rho = 0.28, p < 0.001). ARH positively correlated with tree pollen counts (Spearman rho = 0.2389, p < 0.001). CONCLUSIONS: There exists a significant association between spring AREDV and ARH and tree pollen concentrations in a highly urbanized area such as the Bronx. Early anticipation of spring pollen peaks based on ongoing surveillance could potentially guide clinical practice and minimize asthma-related ED visits in the Bronx.

Methamphetamine alters blood brain barrier permeability via the modulation of tight junction expression: Implication for HIV-1 neuropathogenesis in the context of drug abuse.

The pathogenesis of human immunodeficiency virus (HIV) associated encephalopathy is attributed to infiltration of the central nervous system (CNS) by HIV-1 infected mononuclear cells that transmigrate across the blood brain barrier (BBB). The endothelial tight junctions (TJ) of the blood brain barrier (BBB) play a critical role in controlling cellular traffic into the CNS. Neuropathogenesis of HIV-1 is exacerbated by drugs of abuse such as methamphetamine (Meth) which are capable of dysregulating BBB function. HIV-1 viral proteins like gp120 are both neurotoxic and cytotoxic and have been implicated in the development of HIV-1 dementia (HAD). We hypothesize that gp120 in synergy with Meth can alter BBB permeability via the modulation of tight junction expression. We investigated the effect of Meth and/or gp120 on the basal expression of TJ proteins ZO-1, JAM-2, Occludin, Claudin-3 and Claudin-5, using in vitro cultures of the primary brain microvascular endothelial cells (BMVEC). Further, the functional effects of TJ modulation were assessed using an in vitro BBB model, that allowed measurement of BBB permeability using TEER measurements and transendothelial migration of immunocompetent cells. Our results show that both Meth and gp120 individually and in combination, modulated TJ expression, and these effects involved Rho-A activation. Further, both Meth and gp120 alone and in combination significantly decreased transendothelial resistance across the in vitro BBB and the enhanced transendothelial migration of immunocompetent cells across the BBB. An understanding of the mechanisms of BBB breakdown that lead to neurotoxicity is crucial to the development of therapeutic modalities for Meth abusing HAD patients.

Successful Graded Dose Challenge to Iodixanol Radiocontrast Media in a Patient With Delayed Anaphylaxis to Iohexol.

We present a case of an 82-year-old male with known radiocontrast media (RCM) hypersensitivity who was admitted to our hospital with gangrene of his right toe. The plan for revascularization of his lower extremity required an angiogram. This presented a management challenge as the patient had experienced 2 episodes of delayed anaphylaxis to Omnipaque (iohexol) RCM, and based on a literature review, there was no known or established precedent on a safe procedure in these situations. The patient was premedicated and given a graded dose challenge of an alternative RCM (iodixanol) prior to the radiographic study. He was given 1% of the total expected dose 1 hour before to the procedure and an additional 10% for the 30 minutes prior. He was then given the final dose in the operating room. Following angiogram, the patient was monitored for 18 hours in the postanesthesia care unit, with no adverse reactions. He was placed on a prednisone taper for 1 week, with daily diphenhydramine. The patient remained asymptomatic throughout the hospital course. This novel approach to RCM hypersensitivity management lends itself to a hope that graded dose challenges may play a greater role in the management of these patients.