Prevalence of myopia in open angle glaucoma.

In this study concerning the prevalence of myopia in patients with open angle glaucoma, its distribution was analyzed within the sample tested in relation to the refraction defect size, compared with a control group of non-glaucomatous myopic subjects. The overall myopic rate was 17.2% of the glaucomatous patients; high myopia was more frequent in the subjects with open angle glaucoma (p less than 0.001) than in the myopic patients, thus appearing as a possible risk factor for the development of glaucoma.     

Prevalence of migraine in low-tension glaucoma and primary open-angle glaucoma in Japanese.

We studied the prevalence of migraine in low-tension glaucoma (LTG) and primary open-angle glaucoma (POAG). Seventy seven Japanese patients with LTG, 73 with POAG, and 75 normal subjects were randomly selected and tested with a headache questionnaire. The prevalence of headache with or without typical migrainous features (unilateral headache or ocular pain, nausea, vomiting, and visual disturbance before headache) was 51% in LTG, 42% in POAG, and 44% in normal patients. The prevalence of headache with two migrainous features or more (probable migraine) was 17% in LTG, 11% in POAG, and 12% in normal subjects. The prevalence of headache with three migrainous features (classical migraine) was 5% in LTG, 3% in POAG, and 3% in normal subjects. There was no statistically significant difference in the prevalence of any types of migraine between the three groups of patients (p greater than 0.05). These results suggest there is no significant relationship between migraine and LTG or POAG in Japanese patients.     

The computer in clinical research. Prevalence of glaucoma

The prevalence of glaucoma in a rural population of 6232 people over the age of 40 years, including patients with previously diagnosed glaucoma, was found to be 1.21%. There were 41 cases of open-angle glaucoma compared to 32 cases of angleclosure glaucoma. The prevalence of glaucoma among subjects over the age of 60 years was 3.07%.     

Corticosteroid-induced ocular hypertension. I. Prevalence in closed-angle glaucoma.

Forty-eight eyes with closed-angle glaucoma and 31 eyes at risk were subjected to corticosteroid provocative tests. 65% and 9.7% respectively responded with a change in pressure greater than or equal to 6 mmHg. The responses of the 2 groups were compared with each other and also with the corticosteroid pressure response in normal eyes. The differences in behaviour between the eyes with closed-angle glaucoma and eyes at risk, and the eyes with closed-angle glaucoma and normal eyes, are statistically highly significant. The implication of this are discussed. The prevalence of corticosteroid-induced ocular hypertension in closed-angle glaucoma is higher than previously reported.     

Prevalence of glaucoma in the wroclaw population. The wroclaw epidemiological study

PURPOSE: Primarily to determine the prevalence of various types of glaucoma and ocular hypertension in Wroclaw inhabitants aged 40-79 years. The second aim of the study was to determine the number of undiagnosed glaucoma cases in this population. METHODS: A representative group of the Wroclaw population (4853 people aged from 40 to 79 years) was recruited by a proportional simple random sampling selection with stratification. All participants underwent the first, screening-stage examination, which included a medical history interview, intraocular pressure (IOP) measurement, anterior chamber depth assessment by the Van Herrick technique, and optic nerve head (ONH) assessment by means of indirect ophthalmoscopy (Volk's lens), confocal scanning laser ophthalmoscopy with a Heidelberg Retinal Tomograph (HRT) and scanning laser polarimetry by the GDx Nerve Fiber Analyzer (GDx). The second stage, in glaucoma-suspect patients only, included best corrected visual acuity, static perimetry, 24-hour monitoring of IOP, gonioscopy, and full eye examination with mydriasis. Glaucoma was diagnosed by the presence of any two of the following: characteristic morphological changes in the optic disc, glaucomatous visual field abnormalities, and intraocular pressure greater than 21 mmHg. RESULTS: The overall prevalence of glaucoma was 1.6% (79 subjects). The prevalence increased with age from 0.4% in subjects belonging to the age group 40-49 years to 4.6% in people aged between 70 and 79 years. The prevalence of definite primary open-angle glaucoma was 1.0% (49 subjects). Normal-pressure glaucoma was diagnosed in 13 subjects (0.3%). Ocular hypertension was diagnosed in 92 subjects (1.9%). CONCLUSION: The prevalence of the different types of glaucoma was similar to that found in other white populations. Among the subjects examined, 79 had various forms of glaucoma and 71% of them had not previously been diagnosed. Undiagnosed glaucoma is a serious public health problem in Poland.     

Prevalence of glaucoma in the Israeli Arab population

We describe the prevalence and treatment of glaucoma in a Muslim Arab population in Israel. Based on the medical records of 15 122 persons, the overall prevalence of glaucoma was 3.9%. Prevalence rates of primary open angle glaucoma (POAG) and primary angle-closure glaucoma (PACG) were 3.0% and 0.42%, respectively. Prevalence rates of women were 135% that of men considering all types of glaucoma, 143% for POAG, and 96% for PACG. Prostaglandin analogs and beta blockers, alone or combined with carbonic anhydrase inhibitors, were the preferred medications. Of 68 patients who underwent trabeculectomy, 27 (39.7%) required medications, postoperatively, for treatment of glaucoma; following Ex-Press shunt surgery, 3/11 (27.3%) required medications. During the last three years, 16 (1.3%) individuals with POAG were recorded as legally blind as a result of glaucoma.     

Prevalence of glaucoma. The Beaver Dam Eye Study.

PURPOSE: The purpose of this study is to determine the prevalence of glaucoma in the population participating in the Beaver Dam Eye Study (n = 4926). METHODS: All subjects were examined according to standard protocols, which included applanation tonometry, examination of the anterior chamber, perimetry, grading of fundus photographs of the optic disc, and a medical history interview. Visual field, cup-to-disc ratio, and intraocular pressure (IOP) criteria were used to define the presence of open-angle glaucoma. Definite open-angle glaucoma was defined by the presence of any two or all three of the following: abnormal visual field, large or asymmetric cup-to-disc ratio, high IOP. RESULTS: The overall prevalence of definite open-angle glaucoma was 2.1%. The prevalence increased with age from 0.9% in people 43 to 54 years of age to 4.7% in people 75 years of age or older. There was no significant effect of sex after adjusting for age. Of the 104 cases of definite open-angle glaucoma, 33 had IOPs less than 22 mmHg in the involved eye. Hemorrhage on the optic disc was found in 46 people; 2 of these had glaucoma. Narrow-angle glaucoma was rare, with two definite cases in the population. CONCLUSION: The prevalence of open-angle glaucoma in Beaver Dam is similar to that in other white populations. Findings from this study re-emphasize the notion that estimates of glaucoma prevalence should be based on assessing multiple risk indicators.     

Prevalence of glaucoma in an African population

PURPOSE: To determine the prevalence of primary open-angle glaucoma (POAG) in a Ghanaian population aged 30 years and above and to describe any ethnic variations in glaucoma prevalence in this population. METHOD: A cross-sectional prevalence survey for POAG was carried out on residents of 30 years and above in the Akwapim-South district of Ghana. The principal investigator examined all glaucoma suspects and those diagnosed as glaucoma in the initial screening to determine all definite cases of POAG. All cases had intraocular pressure measurements. Glaucoma cases and suspects and some normal subjects had fundus biomicroscopy with 78 D Volk lens, and Humphrey FDT N-30 visual fields plotted. RESULTS: A total of 1843 people aged 30 years were screened from the population. The standardized age-specific prevalence was 7.7% (30 years and above) and 8.5% (40 years and above). The best-fit trend line for prevalence/age relationship was exponential. No gender or ethnic difference in prevalence was found. CONCLUSIONS: The prevalence of POAG in this population is high and comparable to those in black populations in Barbados and St. Lucia     

Prevalence of debrisoquine oxidation phenotypes in glaucoma patients

The oxidation of debrisoquine, a sympatholytic antihypertensive agent, exhibits genetic polymorphism. The debrisoquine/4-OH-debrisoquine metabolic ratio (MR) separates the population to poor (PM, MR>12.6) and extensive (EM, MR<12.6) metabolizers. 5–10% of the caucasians belong to the PM phenotype. The oxidation of many other drugs, like timolol, correlates with the debrisoquine phenotype.We determined the debrisoquine phenotype in 102 glaucoma patients. The majority of the patients was treated with ophthalmic timolol. Five patients were classified as PMs. However, two of them were on quinidine, a well known inhibitor of debrisoquine oxidation.The prevalence of debrisoquine PM phenotype in glaucoma patients was 2.9% (excluding patients on quinidine) or 4.9% (with patients on quinidine). The figures are slightly lower than the mean value reported for the normal Finnish population. However, both figures lay within the 95% confidence limits of the prevalence of PM phenotype in the normal Finnish population. The beta-blocking activity of oral timolol is increased in PMs. The significance of timolol oxidation phenotype during ocular timolol therapy warrants further investigation.     

Prevalence of glaucoma in treated multibacillary Hansen disease

PURPOSE: To determine the prevalence of glaucoma in a population of patients with multibacillary Hansen disease who had completed treatment. PATIENTS AND METHODS: The authors examined 386 of 446 patients with treated multibacillary Hansen disease residing in a geographically limited area. A complete ophthalmic examination including slit-lamp, applanation tonometry, gonioscopy, ophthalmoscopy, and stereobiomicroscopic examination of the optic disc was performed in all subjects. Glaucoma suspects were invited to the base hospital for further examination including automated perimetry. RESULTS: The overall prevalence of glaucoma was 3.6% (CI 1.9-5.3); 1.3% had primary open-angle glaucoma, 7% were primary angle-closure suspects (occludable angles), 1.8% had primary angle-closure glaucoma, and 0.5% had secondary glaucoma. CONCLUSION: The prevalence of primary glaucoma in patients with treated multibacillary Hansen disease was similar to that in the general population, and secondary glaucoma was rare.     

Prevalence of normal-tension glaucoma and primary open-angle glaucoma in patients with collagen diseases

PURPOSE: To investigate the prevalence of normal-tension glaucoma (NTG) and primary open-angle glaucoma (POAG) in patients with collagen diseases and determine whether an immunocompromised condition is present in a subset of glaucoma patients. METHODS: Three glaucoma specialists prospectively examined patients with collagen diseases. The diagnostic process included applanation tonometry, slit-lamp examination, gonioscopy, direct ophthalmoscopy, and automated static perimetry. Twenty-four-hour intraocular pressure monitoring was done when necessary. Using the results of a population-based survey conducted in Japan, we calculated an expected number of cases of NTG and POAG, and compared these with the actual number of cases. RESULTS: Of the 153 patients with collagen diseases examined, we found 6 patients with NTG and 2 patients with POAG. Of these 8 patients, 2 with progressive systemic sclerosis (PSS), one with NTG, and the other, POAG, had a history of being on systemic steroidal therapy. The prevalence of NTG and POAG was significantly higher in women patients having collagen diseases as compared with normal women (P = .027). CONCLUSION: Women patients with collagen diseases are highly susceptible to NTG and POAG.     

Prevalence of glaucoma in an eye hospital in Nigeria

A study of glaucoma prevalence in Nigeria was undertaken using data from the eye clinic records of 622 females aged between 4 and 80 years and 1055 males aged between 5 and 95 years who attended the Evangelical Churches of West Africa Eye Hospital, Kano, northern Nigeria, in January, 1985. Glaucoma occurred in 8.6% of the patients. Comparative analysis of glaucoma prevalence studies from different parts of the world and using different sampling techniques showed a marked variation.     

The middle-Norway eye-screening study. II. Prevalence of simple and capsular glaucoma

In this population-based screening study, dealing with 1941 persons above 64 years of age from three different municipalities, the overall open-angle glaucoma prevalence was found to be 8.3%. The prevalence in the separate areas (7.0%, 8.6%, and 9.5%) were not statistically different. Roughly 30% of the population with pseudo-exfoliation syndrome had glaucoma, and 4.2% had ocular hypertension, whereas the corresponding figures for those without pseudo-exfoliation were 4% and 0.8%, respectively. The high glaucoma rates are partly due to the high pseudo-exfoliation prevalence in the area. The prevalence of the capsular glaucoma increased towards a maximum between 75 and 79 years of age, whereafter the curve declined. This may indicate reduced survival time of glaucomatous patients.     

Prevalence of glaucoma in rural Myanmar: the Meiktila Eye Study

AIM: To determine the prevalence of glaucoma in the Meiktila district of central, rural Myanmar. METHODS: A cross-sectional, population-based survey of inhabitants > or =40 years of age from villages in Meiktila district, Myanmar, was performed; 2481 eligible participants were identified and 2076 participated in the study. The ophthalmic examination included Snellen visual acuity, slit-lamp examination, tonometry, gonioscopy, dilated stereoscopic fundus examination and full-threshold perimetry. Glaucoma was classified into clinical subtypes and categorised into three levels according to diagnostic evidence. RESULTS: Glaucoma was diagnosed in 1997 (80.5%) participants. The prevalence of glaucoma of any category in at least one eye was 4.9% (95% CI 4.1 to 5.7; n = 101). The overall prevalence of primary angle-closure glaucoma (PACG) was 2.5% (95% CI 1.5 to 3.5) and of primary open-angle glaucoma (POAG) was 2.0% (95% CI 0.9 to 3.1). PACG accounted for 84% of all blindness due to glaucoma, with the majority due to acute angle-closure glaucoma (AACG). CONCLUSION: The prevalence of glaucoma in the population aged > or =40 years in rural, central Myanmar was 4.9%. The ratio of PACG to POAG was approximately 1.25:1. PACG has a high visual morbidity and AACG is visually devastating in this community. Screening programmes should be directed at PACG, and further study of the underlying mechanisms of PACG is needed in this population.     

Prevalence of open-angle glaucoma in Greece: the Thessaloniki Eye Study

PURPOSE: To estimate the prevalence of open-angle glaucoma (OAG) in a population-based sample of subjects 60 years of age or older in Thessaloniki, Greece. DESIGN: Cross-sectional population-based study. METHODS: Subjects randomly identified from municipality registers in Thessaloniki underwent a complete ophthalmologic examination. Glaucoma was defined in two ways. Definition 1 was based on the presence of both glaucomatous optic disk and confirmed glaucomatous visual field defect. Subjects also were classified as having glaucoma when the clinical judgment was strongly in favor of the presence of glaucoma even though the strict criteria were not fulfilled (definition 2). RESULTS: Of the 3,617 eligible subjects, 2,554 (71%) participated. The prevalence of OAG was 3.8% and 5.5% by definitions 1 and 2, respectively. The prevalence of primary OAG was 2.7% and 3.8% by definitions 1 and 2, respectively, and the prevalence of pseudoexfoliation glaucoma (PEXG) was 1.1% and 1.7% by definitions 1 and 2, respectively. Pseudoexfoliation was present in 11.9% of participants, whereas 15.2% among those with pseudoexfoliation had PEXG. CONCLUSIONS: The prevalence of OAG in the Thessaloniki Eye Study (TES) is similar or slightly higher compared with other population-based studies in White persons. The overall slightly higher prevalence of OAG in the TES compared with other studies may be attributed to the high prevalence of PEXG in the TES.     

Prevalence of glaucoma in a rural East African population

PURPOSE: To determine the prevalence of glaucoma in an adult population in rural central Tanzania. METHODS: Six villages were randomly selected from eligible villages in the Kongwa district, and all residents more than 40 years of age were enumerated and invited to a comprehensive eye examination including presenting visual acuity, refraction, automated 40-point Dicon (San Diego, CA) suprathreshold screening field test, Tono-Pen (Bio-Rad, Inc., Boston, MA) intraocular pressure (IOP) measurement, and standardized examination by an ophthalmologist of anterior segment, optic nerve head, and retina after pupil dilation. Gonioscopy and Glaucoma-Scope (Ophthalmic Imaging Systems, Sacramento, CA) optic disc imaging were performed on those with IOP higher than 23 mm Hg and cup-to-disc ratio (c/d) more than 0.6 and on a 20% random sample of participants. RESULTS: Of 3641 eligible persons, 3268 (90%) underwent ophthalmic examination. The prevalence of glaucoma of all types was 4.16% (95% confidence interval [CI] = 3.5, 4.9%). Primary open-angle glaucoma (OAG) was diagnosed in 3.1% (95% CI = 2.5, 3.8%), primary angle-closure glaucoma (ACG) in 0.59% (95% CI = 0.35, 0.91%), and other forms of glaucoma in 0.49%. The prevalence of glaucoma was found to be sensitive to changes in the diagnostic criteria. CONCLUSIONS: The high prevalence of OAG in this group was similar to that of African-derived persons in the United States but less than in African-Caribbean populations. ACG was more prevalent in east Africans than suggested by anecdotal reports.