Corneal Nerve Morphology, Sensitivity, and Tear Neuropeptides in Contact Lens Wear

Experimental Eye Research, 76(5), 521-542

Dry eye syndrome (DES) is believed to be one of the most common ocular problems in the United States (US), particularly among older women. However, there are few studies describing the magnitude of the problem in women and how this may vary with demographic characteristics. Cross-sectional prevalence survey. we surveyed 39,876 US women participating in the Women's Health Study about a history of diagnosed DES and dry eye symptoms. we defined DES as the presence of clinically diagnosed DES or severe symptoms (both dryness and irritation constantly or often). We calculated the age-specific prevalence of DES and adjusted the overall prevalence to the age distribution of women in the US population. We used logistic regression to examine associations between DES and other demographic factors. The prevalence of DES increased with age, from 5.7% among women or = 75 years old. The age-adjusted prevalence of DES was 7.8%, or 3.23 million women aged > or = 50 in the US. Compared with Whites, Hispanic (odds ratio [OR] = 1.81, confidence interval [CI] = 1.18-2.80) and Asian (OR = 1.77, CI = 1.17-2.69) women were more likely to report severe symptoms, but not clinically diagnosed DES. There were no significant differences by income (P([trend]) =.78), but more educated women were less likely to have DES (P([trend]) =.03). Women from the South had the highest prevalence of DES, though the magnitude of geographic differences was modest. Dry eye syndrome leading to a clinical diagnosis or severe symptoms is prevalent, affecting over 3.2 million American women middle-aged and older. Although the condition is more prevalent among older women, it also affects many women in their 40s and 50s. Further research is needed to better understand DES and its impact on public health and quality of life.

To evaluate the use of tear osmolarity in the diagnosis of dry eye disease. A prospective, observational case series to determine the clinical usefulness of tear osmolarity and commonly used objective tests to diagnose dry eye disease. A multicenter, 10-site study consisting of 314 consecutive subjects between 18 and 82 years of age. Bilateral tear osmolarity, tear film break-up time (TBUT), corneal staining, conjunctival staining, Schirmer test, and meibomian gland grading were performed. Diagnostic performance was measured against a composite index of objective measurements that classified subjects as having normal, mild or moderate, or severe dry eye. The main outcome measures were sensitivity, specificity, area under the receiver operating characteristic curve, and intereye variability. Of the 6 tests, tear osmolarity was found to have superior diagnostic performance. The most sensitive threshold between normal and mild or moderate subjects was found to be 308 mOsms/L, whereas the most specific was found at 315 mOsms/L. At a cutoff of 312 mOsms/L, tear hyperosmolarity exhibited 73% sensitivity and 92% specificity. By contrast, the other common tests exhibited either poor sensitivity (corneal staining, 54%; conjunctival staining, 60%; meibomian gland grading, 61%) or poor specificity (tear film break-up time, 45%; Schirmer test, 51%). Tear osmolarity also had the highest area under the receiver operating characteristic curve (0.89). Intereye differences in osmolarity were found to correlate with increasing disease severity (r(2) = 0.32). Tear osmolarity is the best single metric both to diagnose and classify dry eye disease. Intereye variability is a characteristic of dry eye not seen in normal subjects. Copyright © 2011 Elsevier Inc. All rights reserved.