Glaucoma Study – FISH April-May 2010 Jamaica

A look at the available knowledge suggests that: the World Health Organization (WHO) considers Glaucoma to be the third leading cause of blindness around the World.  In the United States, Open Angle Glaucoma is considered to be the leading cause of blindness among persons of African descent. The Barbados Eye Study confirms that the disease is a major cause of blindness in the country with a prevalence of more than 9% in persons over fifty years of age. In Jamaica, not much is known about the public’s understanding about the: Causes, symptoms, diagnosis, social and psychological   implications of the disease.

2.1       WHO’S Definition of Glaucoma

According to the Bulletin of the World Health Organization (WHO) A major difficulty with glaucoma and the blindness that it can lead to is the lack of a uniformed case definition, (WHO, 2005).

This International Public Health Organization confirms that “Glaucoma commonly refers not to a single disease, but to a group of disorders that have certain common features, in particular:

–       Cupping and atrophy of the optic nerve head;

–       Characteristic visual field loss; and

–       Often, but not invariably, increased intraocular pressure.” WHO (2005).

In emphasizing the contribution of glaucoma to blindness around the world, WHO noted that:  If available data on blindness from 1984 are updated to the 1990 global population, it can be assumed that there are currently 35 million blind persons in the world, applying the international definition of blindness as the inability to count fingers at a distance of 3 meters or 10 feet, (WHO, (2005). the organization makes the point that,  Of the above estimate, 5.2 million individuals are blind due to glaucoma indicating that this condition is responsible for 15% of global blindness. This implies that glaucoma is the third most important global cause of blindness, after cataract and trachoma, (WHO, 2005).

2.2       Impact of Glaucoma on Black People:

Glaucoma is the leading cause of incurable bilateral blindness among persons who are black and over forty years of age. In her article entitled Screening for Glaucoma, Mary Calvagna noted that:  In black people, open-angle glaucoma is the leading cause of blindness, and is six to eight times more common than in Caucasians. In addition, the risk among black people increases after age 40, (Calvagna M., 2005).

Glaucoma develops – largely without symptoms. As the leading cause of incurable blindness among persons who are black, glaucoma is often without symptoms, until it approaches what is known as “end-stage” glaucoma. In her article, Calvagna argues that:   In the early stages of the disease, most cases of open-angle glaucoma present no noticeable signs or symptoms. Vision stays normal and there is no pain but even without symptoms, irreversible damage can be happening to your optic nerve, (Calvagna M., 2005).

She makes the point that, the main symptom of glaucoma is loss of peripheral vision. This means that you can see things clearly in front of you, but objects to the side and out of the corner of your eye may be missed, (Calvagna, M. 2005).

Glaucoma is difficult to diagnose and treat. To that end, diagnosis, treatment and prognosis of the condition are complex, but critical steps in the management of the disease. The National Eye Institute, a division of the National Institutes of Health (USA), is a leading supporter of research and related activities to manage and control Glaucoma. The Institute produces regular bulletins on the disease. In a publication posted on its Website, it was noted that the management of Glaucoma includes the following stages:

–           Visual acuity test.

–           Visual field test.

–           Dilated eye exam.

–           Tonometry (The measurement of the pressure inside the eye.)

–           Tachymetry (Use of an ultrasonic wave instrument, to measure the thickness of the patient’s cornea, (National Institutes of Health USA).

2.3       The Barbados Eye Study (BES)

Prior to 1988, meaningful population-based research on glaucoma was not undertaken in any country in the English-speaking Caribbean. Between 1988 and 1992, the National Eye Institute (USA) and the Ministry of Health (Barbados) undertook a population-based study of Open-Angle Glaucoma (OAG). The study was entitled, The Barbados Eye Study, Prevalence of Open Angle Glaucoma.

The study consisted of a simple random sample of Barbadian-born citizens 40 through 84 years old. Some of the conclusions of this study included:  To our knowledge, the Barbados Eye Study is the largest glaucoma study ever conducted in a black population and identified more people with OAG than did any previous population study.

The study found that “The prevalence of OAG was high, especially at older ages, and in men. Among participants 50 years or older, 1 in 11 had OAG, and prevalence increased to one in six at age 70 years or older, (Barbados Eye Study, 1994).  The researchers concluded that, the results highlight the public health importance of OAG in the Afro-Caribbean region and have implications for other populations, (Barbados Eye Study, 1994).

Perhaps one of the most challenging features of glaucoma management is to prevent blindness from the condition; and not to improve vision. The whole purpose of treatment is to prevent further loss of vision. This is imperative as loss of vision due to glaucoma is irreversible, (Glaucoma foundation USA).

2.4       Psychological State of Persons with a Chronic Ailment that may lead to blindness

Although the researcher was unable to find empirical data on the psychological and social effects of glaucoma, the scientific literature has quite useful data and conclusions on the psychological state of persons diagnosed with diabetes.

Because (like glaucoma) diabetes is a chronic condition   which causes permanent blindness (among other disabilities) it is likely that the psychological and social effects may be similar to mental health and social consequences which may arise from a diagnosis of glaucoma.

Therefore, in an effort to establish a  (possible) grounding in   psychology  for this study, this researcher examined two studies with varying conclusions regarding the psychological implications of a diagnosis of diabetes. In a randomized controlled trial of 461 outpatients with diabetes who were randomly assigned to standard care or to the monitoring condition a team of researchers in Holland investigated,  whether monitoring and discussing psychological well-being in outpatients with diabetes improves mood, glycemic control, and the patient’s evaluation of the quality of diabetes care, (Francois Pouwer et al, 2001).

Interestingly, the researchers found that some patients who indicated abnormal psychological states, following a diagnosis of diabetes, benefited from counseling and other types of mental health interventions. The monitoring group reported better mood compared with the standard care group, as indicated by significantly lower negative well-being and significantly higher levels of energy, higher general well-being, better mental health, and a more positive evaluation of the quality of the emotional support received from the diabetes nurse, (Francis Pouwer et al, 2001).

Similar (but not identical) results were reported   in a study undertaken in two outpatient diabetes mellitus clinics in Pretoria, South Africa. The objective of that study was given as:   To determine the underlying dimensions of a social support measure and investigate the effects of social support on health, well-being and management of diabetes mellitus (metabolic control and blood pressure) BP) control,  (Margaret S. Westaway, John R. Seager et al,  2005).

This researcher considers the findings of that study, most pertinent to the Jamaican situation, because of the race profile of the participants, and the likelihood of some genetic and basic cultural factors which could have resonance in the Jamaican context. It is noteworthy that the participants were 263 black diabetes mellitus outpatients (174 women and 89 men), aged between 16 and 89 years, (Margaret S. Westaway, John R. Seager, et al, 2005).

Interestingly, but not surprisingly, the study found in favour of benefits to be derived from higher levels of support to persons diagnosed with diabetes. Patients with lower levels of social support had poorer general health and well-being than patients with higher levels of social support, (Margaret S. Westaway, John R. Seager, et al, 2005).

The broader findings of this study seem to point the way toward more in depth studies, regarding the effects of psychological, social and in-kind support, on persons diagnosed with a range of chronic non-communicable conditions, including glaucoma. The study demonstrated that: (1) socio-emotional and tangible support was the underlying dimensions of social support; (2) socio-emotional support is an important determinant of health and well-being; and (3) social support is beneficial for one aspect of diabetes mellitus management, namely, blood pressure control, (Margaret S. Westaway, John R. Seager, Et Al, 2005).

While the literature is silent regarding the possible social and psychological effects of a diagnosis of glaucoma, the data seem to suggest that, persons diagnosed with diabetes, are at risk of some degree of psychological and social deficit. This study will seek to narrow the search for evidence specifically relating to persons diagnosed with glaucoma, and attending the Foundation for International Self Help Medical Center, in Jamaica.

Chapter 3 – Methodology

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