As dedicated eye care practitioners, it is our responsibility to be vigilant during ocular examinations—to not only scan for eye problems, but also associated morbidity secondary to systemic disease. This is certainly true for any contact lens/anterior segment examination, something we are often called upon to perform several times each day.

In the past, epidemiological studies and careful clinical observation have detected many conditions that were found in tandem. For example, a recent publication by Arie Y. Nemet, M.D., and colleagues highlights the need to consider associated morbidity with one common ocular complication—blepharitis.1 The authors noticed that a significantly higher tendency to develop blepharitis occurs demographically in populations of a lower socioeconomic class, populations living in urban settings and Ashkenazi Jews.1

From a systemic standpoint, the authors notice a significant association with several inflammatory diseases (gastritis, rosacea, peptic ulcer, asthma, arthropathy and ulcerative colitis), psychologic conditions (anxiety, irritable bowel syndrome, neurosis and depression), hormonal anomalies (hypothyroidism and benign prostatic hypertrophy), cardiovascular diseases (carotid artery disease, hypertension, hyperlipidemia and ischemic heart disease) and other eye conditions (chalazion and pterygium).1 It’s important to emphasize that detecting an association of blepharitis with other systemic conditions or diseases does, in no way, establish causality.

Systemic conditions may be indirectly associated with some eye diseases—like blepharitis—through an inflammatory, hormonal or infectious cause, but a direct link is always possible, as cited above.1-6

How do we get from coronary artery disease, hyperlipidemia and ischemic heart disease to a commonly seen eye condition like blepharitis? What might appear to be a really big leap, may actually make sense anatomically. For example, associated cardiovascular disease may have a link to blepharitis. The eyelids and meibomian glands have a rich blood supply and likely affect the function of the glands directly.1

On a related note, a new research frontier has emerged looking at what role different micro-organisms (viruses, fungi and bacteria) play in acquiring diseases and any associated morbidity or co-diseases. A few significant examples include: H. pylori causing peptic ulcers, coronary artery disease and myocardial damage from bacterial infection and the enteroviral infection of beta cells in childhood diabetes.2-4 Additional research is needed to establish cause and effect, mechanisms and ultimately, a cure.

On a higher order, surrogates like Demodex have been implemented in rosacea infectivity—possibly due to the organism carrying the bacteria, Bacillus oleronius.5 In addition, amoebae are the natural host by proxy for Legionella pneumophilia and play an essential role in bacterial ecology and infection in humans.6

Understanding these complex pathophysiologic associations between diseases and their triggers may eventually help practitioners recognize, treat and manage various conditions. Avoiding the possible triggers or blocking the responsible pathways should improve the prognosis and minimize associated morbidity that is commonly encountered in many of these conditions.

Remember to always practice with your eyes wide open in order to recognize the connections between clinically seen ailments to systemic diseases, even when they may not make a lot of sense at first glance. This is all part of our job as we attempt to “crack the code.” 

1. Nemet AY, Vinker S, Kaiserman I. Associated morbidity of blepharitis. Ophthalmology. 2011 Jun;118(6):1062-8.
2. U.S. Department of Health and Human Services. National Digestive Diseases Information Clearinghouse. NIH Publication No. 10-4225. 2010 Apr. Available at: (accessed July 2011).
3. Stollberger C, Molzer G, Finsterer J. Seroprevalence of antibodies to microorganisms known to cause arterial and myocardial damage in patients with or without coronary stensosis. Clin Diagn Lab Immunol. 2001 Sep;8(5):997-1002.
4. Kahn M. Studies point to viruses as cause of diabetes. Reuters. 2009 Mar 5. Available at: (accessed July 2011).
5. Pascoe D. Where the rosacea community meets to support each other. Rosacea Support Group. 2007 Jul. Available at: (accessed July 2011).
6. Garcia MT, Jones S, Pelaz C, et al. Acanthamoeba polyphaga resuscitates viable non-culturable Legionella pneumophilia after disinfection. Environ Microbiol. 2007 May;9(5):1267-77.