• Cornea/External Disease, Refractive Mgmt/Intervention

    Review of: The role of temperature change, ambient temperature, and relative humidity in allergic conjunctivitis in a U.S. veteran population

    Patel S, Kaplan C, Galor A, et al. American Journal of Ophthalmology, in press

    Using national health and weather datasets, researchers examined the relationship between meteorological conditions and risk of a visit for allergic conjunctivitis (AC).

    Study design

    This retrospective, case-crossover study included patient data from 74,951 individuals from a Veterans Affairs clinic and local climate data from the National Climactic Data Center. All patients were assigned a random control date prior to diagnosis and the daily time-lagged exposures were computed for 30-day lags. Investigators calculated associations between temperature, temperature variation, relative humidity, temperature-humidity interactions and visit risk.

    Outcomes

    Prevalence of AC visits was highest in spring (>10% April–May) in the Northeast and Southeast, and lowest in winter (<6.1% December–February) in the Pacific Northwest. Risk of an AC visit was positively tied to temperatures, temperature variation and temperature-relative humidity interaction and negatively linked with relative humidity. The associations were strongest in the Pacific Northwest, Northeast and Lower Midwest.

    Limitations

    The study was limited to a veteran population older than typical allergic conjunctivitis patients such as those undergoing cataract or refractive surgery.

    Clinical significance

    This is an interesting study that looked at clinical visits for allergic conjunctivitis among various regional populations. The authors used a very large dataset that could be mirrored in a younger population undergoing refractive surgery.