Latest glaucoma research

Nov 10 2008

Glaucoma-related highlights of today's scientific program of the 2008 Joint Meeting of the American Academy of Ophthalmology (Academy) and European Society of Ophthalmology (SOE) include a study that correlates optic nerve damage in glaucoma patients with carotid artery narrowing and potentially elevated risk for stroke, and a survey that looks at how the practice of fasting, common to the world's seven major religions, may affect patient compliance with treatment for glaucoma and other eye diseases.

Damage to Optic Nerve in Glaucoma Patients May Indicate Significant Carotid Artery Narrowing

Glaucoma is often associated with elevated pressure inside the eye (intraocular pressure, or IOP) which can damage the optic nerve, leading to vision loss and even blindness. Medication and/or surgery allow patients to control their IOP, thus preventing the development of vision loss. Mostafa Elgohary, MD, of Essex County and Broomfield Hospitals in the UK and his colleagues were concerned when several patients who had been under their care for several years continued to lose their vision in one or both eyes even though their IOP had been kept within normal limits either through medicine or surgery.

The authors reviewed 16 retrospective case reports to determine if there was a possible association of internal carotid artery narrowing, or stenosis, with the development of glaucoma or glaucoma-like damage to the optic nerve. The internal carotid arteries are the main arteries in the neck that carry the blood to the brain and the eye. On further investigation, the authors found that six of those patients had significant carotid artery narrowing (greater than 60 percent of the artery lumen) and some even had total blockage of the artery on the same side as the eye with the glaucoma, or on both sides. One patient showed improvement in the visual field after undergoing surgery to remove the blockage. The authors then extended their investigation by prospectively collecting data for 58 patients who were referred with similar optic nerve or visual field changes and carotid artery stenosis as part of the hospital audit system and found that 17 percent of these patients had significant carotid artery narrowing.

The study results are significant because they add to the evidence for the role of reduced blood flow to the optic nerve as a possible cause or predisposing factor for glaucoma or glaucoma-like optic nerve damage. Moreover, the results indicate a possible association with significant carotid artery narrowing which is a potentially serious condition as it carries the risk of stroke. " The study is of a small scale and will obviously need further research to confirm the findings, " the authors say. " However, in the meantime it may be prudent to consider referring patients with progressive or asymmetric glaucoma despite normal eye pressure -- especially in the presence of cardiovascular risk factors such as hypertension, hypercholesterolemia or ischemia heart disease -- for carotid artery Doppler scan to pick up those who could be at high risk for stroke and may benefit from carotid artery treatment. "

Could Religious Beliefs Affect Compliance with Ocular Treatment?

For people of strong faith, religious beliefs and related cultural taboos can have a powerful impact on how they care for their health, including the medical treatments they choose to accept. Increasingly, ophthalmologists (Eye M.D.s) in the US and other countries, care for patients of diverse backgrounds. This is accelerating the need for reliable information on the interaction of religious beliefs and compliance with prescribed treatments. The effectiveness of glaucoma treatment, in particular, often depends on patients ' ability and willingness to self-administer eye drop medications on a regular schedule over months or years. Glaucoma patients often notice no symptoms in the early stages of the disease, which poses challenges for physicians in motivating patients to stick to treatment regimens. If patients neglect treatment until their vision noticeably declines, the damage is often irreversible.

Many of the world's religions practice obligatory or voluntary fasting -- abstaining from food and often also fluid -- during periods that can last from a few days to more than a month, on an annual basis. Researchers led by Nishant Kumar, MBBS, of the University Hospital, Liverpool, UK, studied patient compliance in relation to fasting by analyzing 350 surveys completed by members of the worlds ' major faiths: Islam, Hinduism, Jainism, Christianity, Judaism, Bahai, and Buddhism (50 surveys per religion) - the first study of its kind, the researchers believe. Population reports show that approximately 20 percent of the world's people are Muslim and about 15 percent are Hindu; fasting is important to both religions. It is mandatory during the daylight hours of the month of Ramadan for Muslims; for Hindus fasting is generally voluntary.

Dr. Kumar's team previously surveyed Muslim patients on their use of prescribed eye drops during Ramadan and concluded that treatment compliance was significantly reduced in patients who kept the fast. If patients reduced or stopped their glaucoma treatment for an extended period, such as the month of Ramadan or other continuous fasting periods, their vision could be adversely affected.

In the new survey, the majority of patients self-identified as Hindus, Muslims and Jains stated that the use of eye drops during their fasting hours would break their fast, and therefore they would not use drops while fasting. However, these patient groups said they would be more likely to use drops while fasting for painful eye conditions or if vision was affected. The majority of Christian, Buddhist, Bahai and Jewish survey respondents did not believe that using drops would break their fasts, and stated that they would use eye drops during their fasting periods.

Dr. Kumar concludes: " A broad awareness among ophthalmologists regarding the religious beliefs of the patient groups they treat will allow them to formulate management plans in keeping with these beliefs without compromising care. " He adds that medical specialties such as hematology, neurology, endocrinology, in the treatment of diabetes, have led the way in developing such management strategies.