Prevalence of Primary Open Angle Glaucoma in Patients with Hypertension

Prevalence of Primary Open Angle Glaucoma in Patients with Hypertension Archana Pushpakaran, Sedhu P. A, Ashwati Sankar, Cyriac Kurien Associate Professor, SreeNarayana Institute of Medical Sciences, Chalakka, Kochi, 2 Professor, SreeNarayana Institute of Medical Sciences, Chalakka, Kochi, Assistant Professor, SreeNarayana Institute of Medical Sciences, Chalakka, Kochi, Professor & HOD, SreeNarayana Institute of Medical Sciences, Chalakka, Kochi. Background: Glaucoma is the second most common cause of blindness worldwide. It is one of the leading causes of irreversible blindness in the adult population worldwide. Glaucoma is a progressive optic neuropathy. The present study was conducted to assess prevalence of primary open angle glaucoma in patients with hypertension. Subjects and Methods: This crosssectional study was conducted in outpatient department of Sree Narayana Institute of Medical Sciences. A total of 100 patients with hypertension were included in the study. Prevalence of primary open angle glaucoma in patients with HTN was recorded. Results: Out of 100,59 were males and 41 were females. Among the 100 hypertensive patients, 5% of patients had POAG. Among POAG, 3 were males and 2 were females. The percentage of patients with IOP between 8-21 was 95%, I0P >21 was 5% in right eye. The percentage of patients with IOP in between 8-21 was 95%, IOP >21 was 5% in left eye. Conclusion: High myopia, hypertension, diabetes mellitus has been associated with POAG, however, direct and convincing evidences


Introduction
Glaucoma is the second most common cause of blindness worldwide. It is a major global issue, causing significant ocular morbidity and disability due to its progressive nature resulting in an irreversible visual loss. Due to its chronicity, it is often also dubbed as a "silent killer" of the eye. Patients are usually asymptomatic until very advanced stage, making visual loss irrecoverable by the time they present to an ophthalmologist. [1] One of its variant and the most common formprimary open-angle glaucoma (POAG) is a chronic, progressive, and anterior optic neuropathy that is associated with characteristic cupping and atrophy of the optic disc, visual field loss, open angles, and no obvious causative ocular or systemic conditions. POAG accounts for nearly three quarters (74%) of all glaucoma cases. [2] Hypertension (HT) and cardiovascular disorders are the most common systemic diseases seen in glaucoma subjects. Hypertension (HTN) data on the relationship among HTN and intraocular pressure (IOP) are consistent across examination. This relation between POAG and blood pressure (BP) is unpredictable and inadequately understood. [3] Among vascular factors, it has been long postulated that systemic HTN may cause increases in IOP mainly via overproduction from ciliary body or impaired outflow of aqueous humor. However, this relationship remains inconclusive and under debate. While some studies highlight that systemic HTN is a risk factor for glaucoma, other studies indicate that low systemic BP is more dangerous and poses a serious risk for the development and progression of glaucoma. [4] The present study was conducted to assess prevalence of primary open angle glaucoma in patients with hypertension.

subjects and Methods
The present cross-sectional study was conducted in outpatient department of Sree Narayana Institute of Medical Sciences. It comprised of 100 patients with hypertension. The study was approved by the institutional ethics committee. Data such as name, age, gender etc. was recorded. In all thorough physical examination was performed. Best corrected visual acuity (BCVA) was assessed using an illuminattxSnellen's chart. Near vision was assessed, using Jaeger's near vision chart. Colour vision was checked using Ishihara's pseudo-isochromatic charts. BCVA was checked by Skiascopy or streak retinoscopy. Slit lamp examination was performed to rule out anterior segment pathology. Gonioscopy was done with Goldmann's three mirror goniolens and the anterior chamber angle was graded according to modified Shaffer's grading.

Pushpakaran et al; Primary Open Angle Glaucoma in Patients with Hypertension
Dilated fundus examination by indirect ophthalmoscopy, followed by a slit lamp biomicroscopic evaluation with 78 D lens and 90 D lens to evaluate the posterior pole including the optic disc was done. Patients were evaluated for some parameters such as C:D ratio, 10P, visual fields, each eye separately. Data was presented as mean and standard deviation for continuous variables. Statistical significance was considered when P was < 0.05.     Table 3 shows that 3 were males and 2 were females. Figure  1 shows that the percentage of patients with IOP in RE between 8-21 was 95%, I0P >21 was 5%. Figure 2 shows that the percentage of patients with IOP in LE between 8-21 was 95%, IOP >21 was 5%.

Discussion
In addition to the effect of these systemic illnesses on glaucoma, the interplay of multiple medications used to manage these co-existing ocular and systemic diseases needs to be taken into consideration both by the treating physician and ophthalmologist. [5] While in some cases systemic medications may decrease the intraocular pressure (IOP)-lowering effect of the topical medications, the simultaneous use of some ocular and systemic medications may lead to more sinister effects like metabolic disorders and cardio respiratory depression. [6] The present study was conducted to assess prevalence of primary open angle glaucoma in patients with hypertension.
In this study, out of 100, 59 were males and 41 were females. Among the 100 hypertensive patients, 5% of patients had POAG. Bonomi et al, [7] conducted a study to record the prevalence and systemic control and evaluate the adequacy of therapy of hypertension (HT) in glaucoma patients.

Pushpakaran et al; Primary Open Angle Glaucoma in Patients with Hypertension
cannot be overemphasized. [9] Conclusion Glaucoma, one of the leading causes of irreversible blindness in the adult population worldwide, is a progressive optic neuropathy. Primary open angle glaucoma (POAG) is the most commonly reported type of glaucoma in population based prevalence studies worldwide. Many studies found that high myopia, hypertension, diabetes mellitus has been associated with POAG, however, direct and convincing evidences are still lacking.