The Role of Temperature Change, Ambient Temperature, and Relative Humidity in Allergic Conjunctivitis in a US Veteran Population.

PURPOSE: Studies have implicated temperature and humidity in the pathogenesis of allergic conjunctivitis (AC), as these conditions facilitate air particulate and aeroallergen dispersion and tear film instability. Research also suggests that variation in temperature is associated with risk of asthma, but similar data are limited for AC. This study examined associations between several meteorologic conditions, including temperature variation, and AC visit risk. DESIGN: Retrospective, case-crossover study. METHODS: Data on individuals diagnosed with AC (via International Classification of Diseases-Ninth Edition [ICD-9]) at a Veterans Affairs clinic from January 2010-December 2013 was extracted. Local climate data were obtained from the National Climactic Data Center. Utilizing a case-crossover design, all cases were assigned a random control date 90-250 days prior to diagnosis. Daily time-lagged exposures were computed for 30-day lags. The associations between temperature, temperature variation (standard deviation [SD] of temperature), relative humidity (RH), and temperature-RH interaction with visit risk were examined via multivariate logistic regression models both at the national level and across domestic climate regions. RESULTS: Overall, 74,951 subjects made 116,162 visits for AC. Prevalence was highest in spring (>10% April-May) in the Northeast (NE) and Southeast (SE) (>15%), and lowest in winter (<6.1% December-February) in the Pacific Northwest (PNW) (<5%). AC visit risk was positively associated with temperature (OR 1.028, P < .001), SD of temperature (OR 1.054, P < .01), and temperature-RH interaction (OR 1.0003, P < .01), whereas it was negatively associated with RH (OR 0.998, P < .001). Regionally, the PNW, NE, and Lower Midwest (LMW) accounted for the strongest associations. CONCLUSION: Temperature, temperature variation, and RH associated with AC visit risk. Observed associations were strongest in northern regions, like the PNW.

Human Ocular Surface Particulate Composition in the Clinical Versus Home Environment.

PURPOSE: Our eyes are chronically exposed to airborne particulate matter shown to adversely affect the ocular surface. This research examines size, type (organic vs. inorganic), and elemental composition of particles recovered from the ocular surface in 2 environments and their associations with dry eye (DE) metrics. METHODS: Particles were recovered from the right eye using Schirmer strips obtained both in the clinic and home environments 9 ± 8 days apart. Particle size and elemental composition were assessed using scanning electron microscopy and energy dispersive spectroscopy. The paired t test was used to evaluate the differences in the size and types of ocular surface particles recovered from the clinic and home settings. Associations of particle size and type with home environmental conditions and DE measures were evaluated using correlation analyses. RESULTS: The mean age of the 15 patients was 56 years, standard deviation (±) 12 years; 93% were men and 53% self-identified as white. Size, type, and elemental composition did not vary significantly between clinic and home. Particle surface area was marginally associated with home indoor temperature (25 °C ± 2, ρ=-0.53, P = 0.06) and significantly associated with the select DE signs: tear osmolality (304 mOsm/L ± 14, ρ= -0.60, P = 0.02), inflammation (0.7 ± 0.8, ρ = 0.53, P = 0.04), and tear breakup time (7 seconds ± 3, ρ = 0.56, P = 0.03). CONCLUSIONS: Ocular surface particles were consistently detected across 2 different environments. Greater particle area detected on Schirmer strips correlated with some DE measures, suggesting that particles detected on the ocular surface may affect eye health.

Understanding health care personnel's attitudes toward mandatory influenza vaccination.

BACKGROUND: This study investigated the factors influencing influenza vaccination rates among health care personnel (HCP) and explored HCP's attitudes toward a policy of mandatory vaccination. METHODS: In September 2012, a 33-item Web-based questionnaire was administered to 3,054 HCP employed at a tertiary care hospital in metropolitan Detroit. RESULTS: There was a significant increase in the rate of influenza vaccination, from 80% in the 2010-2011 influenza season (before the mandated influenza vaccine) to 93% in 2011-2012 (after the mandate) (P < .0001). Logistic regression showed that HCP with a history of previous influenza vaccination were 7 times more likely than their peers without this history to receive the vaccine in 2011-2012. A pro-mandate attitude toward influenza vaccination was a significant predictor of receiving the vaccine after adjusting for demographics, history of previous vaccination, awareness of the hospital's mandatory vaccination policy, and patient contact while providing care (P = .01). CONCLUSIONS: The increased rate of influenza vaccination among HCP was driven by both an awareness of the mandatory policy and a pro-mandate attitude toward vaccination. The findings of this study call for better education of HCP on the influenza vaccine along with enforcement of a mandatory vaccination policy.