Prevalence,risk factors and association with glycemic levels of presbyopia in South Indian population

Purpose:To determine the prevalence of presbyopia and its association with elevated glycemic levels in subjects ≥40 years of age in the South Indian population of Chennai.Methods:This was a retrospective study. Subjects were included from the Sankara Nethralaya Diabetic Retinopathy Epidemiology And Molecular genetics Study (SN-DREAMS 1). Demographic data, detailed medical and ocular history, comprehensive eye examination, and biochemical investigations were performed. Glycosylated hemoglobin results were categorized as controls (4%–5.6%), prediabetic (5.7%–6.4%), and diabetic (≥6.5%) groups. The given presbyopic correction was divided into two groups as within and outside donders limit. Prevalence rates and mean values were determined and compared among the three glycemic groups. The Student t test, the Chi-square test, and multivariate logistic regression analyses were performed.Results:The overall prevalence of presbyopia from our previously conducted SN-DREAMS 1 population of 1414 patients was 79.77% (95% CI: 0.775–0.818). In total, 1128 participants were included for our current secondary analysis with a mean age of 54.40 years (range: 40–83). The number of subjects within and outside donders limit was 1044 (92.55%) and 84 (7.44%), respectively. In each age group (40–49, 50–59, ≥60) regardless of being within or outside donders limits, an increasing trend in the prevalence of presbyopia was noted based on increasing glycemic levels.Conclusion:Our study demonstrated a high prevalence of presbyopia in the South Indian population of Chennai. Findings show that the prevalence of presbyopia in different age groups increases with worsening diabetes status.     

Prevalence of glaucoma in Thailand: a population based survey in Rom Klao District,Bangkok

AIM: To determine prevalence, demography, mechanism, and visual morbidity of glaucoma in urban Thai people. METHODS: 790 subjects aged 50 years or older from Rom Klao district, Bangkok, Thailand, were enumerated in a population based cross sectional study. Each subject underwent the following investigations: visual acuity, visual field testing, slit lamp examination, applanation tonometry, gonioscopy, and an optic disc examination after mydriasis. Main outcome measures included visual acuity (logMAR), visual fields, intraocular pressure (IOP), gonioscopic characteristics, vertical cup/disc ratio (VCDR), prevalence of types of glaucoma. Glaucoma was diagnosed on the basis of optic disc appearance and visual field defects. In eyes in which the optic disc could not be examined, glaucoma was diagnosed when visual acuity was <3/60 and either IOP >99.5th percentile or there was evidence of previous glaucoma surgery. RESULTS: 701 subjects were examined (response rate 88.7%). In eyes with "normal" suprathreshold visual fields, the mean IOP was 13.3 mm Hg (97.5th percentile = 20 mm Hg). The 97.5th and 99.5th percentiles of VCDR were 0.72 and 0.86 respectively. Of the 701 subjects examined in the clinic, 27 had glaucoma (3.8%, 95% CI: 2.5 to 5.6), 16 had primary open angle glaucoma (POAG, prevalence 2.3%, 95% CI: 1.3 to 3.7), six were primary angle closure glaucoma (PACG, prevalence 0.9%, 95% CI: 0.3 to 1.9), and five were secondary glaucoma (SecG, prevalence 0.7%, 95% CI: 0.2 to 1.7). Among the 43 unilaterally blind subjects, glaucoma was the cause in five subjects (12%). One subject was bilaterally blind due to glaucoma (prevalence 11%, 95% CI: 0.3 to 61.9). 28 people (4%) were glaucoma suspects on the basis of optic disc appearance and six on the basis of visual fields only. 98 subjects (14%) had "occludable angles" in either eye, 22 of whom had primary angle closure (PAC, prevalence 3.1%, 95% CI: 1.9 to 4.7); 14 had peripheral anterior synechiae in either eye and eight had ocular hypertension (OHT). CONCLUSIONS: POAG accounted for 67% of all glaucoma, PACG 21%, and secondary glaucomas 12%. Glaucoma was the second most common cause of severe unilateral visual loss.     

Functional presbyopia in a rural Kenyan population: the unmet presbyopic need

Background: Presbyopia is the most common reason for requiring spectacles in low‐income regions, although the unmet need for presbyopic spectacles in these regions is very high. The aim of this study was to estimate the prevalence of presbyopia, and the functional impairment and spectacle use among persons with presbyopia in a rural Kenyan population. Methods: A cross‐sectional study was carried out in the Rift Valley, Kenya. Clusters were selected through probability‐proportionate to size sampling, and people aged ≥50 years within the clusters were identified through compact segment sampling. Within the context of this survey, 130 eligible participants were selected for interview and underwent near‐vision testing. Functional presbyopia was defined as requiring at least +1.00 dioptre in order to read the N8 optotype at a distance of 40 cm in the participant's usual visual state. Participants were corrected to the nearest 0.25 dioptre in order to see N8. Unmet and met presbyopic need, and presbyopic correction coverage were calculated. Results: Functional presbyopia was found in 111 participants (85.4%). Mean age was lower in those with presbyopia (64.1 years vs. 71.5 years, P = 0.004). Increasing degree of addition required to see N8 was significantly associated with increased difficulty with reading (P = 0.04), sewing (P = 0.03), recognizing small objects (P = 0.02) and harvesting grains (P = 0.05). Among participants with functional presbyopia, 5.4% wore reading glasses and 25.2% had prior contact with an eye care professional. The unmet presbyopic need was 80.0%, met presbyopic need was 5.4% and presbyopic correction coverage was 6.3%. Cost was cited as the main barrier to spectacle use in 62% of participants with presbyopia. Conclusion: In low‐income regions, there is a high prevalence of uncorrected presbyopia, which is associated with near‐vision functional impairment. Provision of spectacles for near vision remains a priority in low‐income regions.     

Glaucoma in southwest Nigeria: clinical presentation,family history and perceptions

International Ophthalmology - Knowledge of the presentation pattern of glaucoma helps in providing more understanding of the disease, leading to better control. The aim of this study was to...     

Prevalence of Trachoma in Jigawa State,Northwestern Nigeria

ABSTRACT

Purpose: To determine the magnitude of trachoma and the prevalent forms of the disease, and to provide baseline data for the establishment of a trachoma control program in Jigawa State, northwestern Nigeria.

Methods: A population-based cross-sectional survey was conducted in Jigawa State in May 2007 using a 2-stage cluster random sampling technique to select 4598 persons from 40 villages based on probability proportional to size. All participants were examined using a penlight and a 2.5?×?binocular loupe for signs of trachoma, and graded using the World Health Organization (WHO) simplified grading system.

Results: A total of 4598 people were seen with 99.96% coverage. Of these, 2460 (53.5%) were female and 2138 (46.5%) were male. Mean age was 21.6 years (?±?19.8 years). The prevalence of follicular trachoma in children aged ≤9 years was 20.5% (95% confidence interval, CI, 18.7–22.4%) with no difference between the sexes. The prevalence of trichiasis in adults aged ≥15 years was 5%, and the prevalence was higher in females than males (odds ratio 2.60, 95% CI 2.06–3.28; p?<?0.001).

Conclusion: Trachoma is a major problem in Jigawa State; there is a need to train trichiasis surgeons and empower them to carry out community-based surgery. District-level prevalence of trachoma needs to be determined to know which aspects of the WHO SAFE strategy (surgery, antibiotics, facial cleanliness and environmental improvements) need to be emphasized in each district.     

Prevalence and risk factors for primary open-angle glaucoma in a rural northeast China population: a population-based survey in Bin County, Harbin

Purpose

To estimate the prevalence and associated risk factors of primary open-angle glaucoma (POAG) in a rural population in northeast China.

Methods

A population-based survey was conducted within Bin County, Harbin of northeast China. Glaucoma was diagnosed using International Society of Geographical and Epidemiological Ophthalmology criteria. All the subjects underwent a complete ophthalmic examination.

Results

A total of 4956 (86.0%) of 5762 subjects aged 40 years or older were examined. The mean intraocular pressure (IOP) of right eyes was 14.0 (95% confidence interval (CI), 13.9 to 14.1) mm Hg. The prevalence of POAG was 0.71% (35/4956, 95% CI, 0.47 to 0.93). In these POAG subjects, 17 (48.6%) had elevated IOP >21 mm Hg in either eye, 3 (8.8%) participants had been treated by laser trabeculoplasty or trabeculectomy and were known to have POAG. Vision impairment to varying degrees was present in 20 subjects (58.8%) with 1 subject blind in both eyes and 8 subjects blind in one eye. On multivariate analysis, age, family history of glaucoma, systemic hypertension, and IOP were regarded as significant independent risk factors.

Conclusions

POAG is a disease of serious consequence and of low diagnosis and treatment rates in rural northeast China. Age, family history of glaucoma, systemic hypertension, and IOP remain as significant independent risk factors for POAG.     

Prevalence of blindness and low vision in a rural population in northern china: preliminary results from a population-based survey

Purpose: To investigate the prevalence of visual impairment in a rural northern Chinese population. Methods: A cross-sectional, population-based survey was conducted in 2010 in Ci County, Hebei Province in northern China. Residents aged 7 years and older in Lucunying Town, located within Ci County, underwent presenting visual acuity (VA) testing at home; those with presenting VA <20/60 were invited to participate in further examination at the local hospital. Population-weighted prevalences of blindness and low vision were determined according to World Health Organization definitions. Results: Among the 24,539 residents aged older than 7 years, 20,298 (82.7%) participated in the study, and 20,072 (98.9%) of these had valid VA data. The population-weighted prevalence rates of presenting bilateral blindness and bilateral low vision were 0.3% and 2.4% for the entire population, 0% and 0.5% for residents 7-39 years of age, and 0.8% and 6.4% for residents 40 years and older, respectively. Based on best-corrected VA, the corresponding prevalence rates of bilateral blindness and bilateral low vision were 0.2% and 1.4% for the entire population, 0% and 0.1% for residents 7-39 years, and 0.6% and 4.0% for residents 40 years and older, respectively. Prevalence rates of blindness and low vision were generally higher among women than men. Blindness and low vision increased with age among residents 40 years and older. Conclusion: Our findings highlight the need for eye healthcare services for visual impairment in rural China.     

An international survey of contact lens prescribing for presbyopia

Purpose: The aim was to determine world‐wide patterns of fitting contact lenses for the correction of presbyopia. Methods: Up to 1,000 survey forms were sent to contact lens fitters in each of 38 countries between January and March every year over five consecutive years (2005 to 2009). Practitioners were asked to record data relating to the first 10 contact lens fittings or refittings performed after receiving the survey form. Results: Data were received relating to 16,680 presbyopic (age 45 years or older) and 84,202 pre‐presbyopic (15 to 44 years) contact lens wearers. Females are over‐represented in presbyopic versus pre‐presbyopic groups, possibly reflecting a stronger desire for the cosmetic benefits of contact lenses among older women. The extent to which multifocal and monovision lenses are prescribed for presbyopes varies considerably among nations, ranging from 79 per cent of all soft lenses in Portugal to zero in Singapore. There appears to be significant under‐prescribing of contact lenses for the correction of presbyopia, although for those who do receive such corrections, three times more multifocal lenses are fitted compared with monovision fittings. Presbyopic corrections are most frequently prescribed for full‐time wear and monthly replacement. Conclusions: Despite apparent improvements in multifocal design and an increase in available multifocal options in recent years, practitioners are still under‐prescribing with respect to the provision of appropriate contact lenses for the correction of presbyopia. Training of contact lens practitioners in presbyopic contact lens fitting should be accelerated and clinical and laboratory research in this field should be intensified to enhance the prospects of meeting the needs of presbyopic contact lens wearers more fully.     

Couching in Nigeria: Prevalence,Risk Factors and Visual Acuity Outcomes

Purpose: Couching is an ancient treatment for cataract which is still practiced in some of the poorer developing countries, particularly in sub-Saharan Africa. The purpose of this study is to describe risk factors for couching and visual acuity outcomes in a nationally representative sample of adults aged 40 years and above in Nigeria.

Methods: Probability in proportion size methods were used to identify a representative sample. Of the 15,375 adults enumerated, 13,582 were interviewed and examined. Examination included logMar acuities, slit lamp examination and dilated fundoscopy with digital fundus imaging.

Results: Almost half of the 583 eyes undergoing a procedure for cataract had been couched (249 eyes, 42.7%). Individuals living in rural areas (P?=?0.033) and in the two underserved northern administrative zones (P?=?0.33; P?=?0.002) were more likely to have been couched. Visual outcomes were poor according to World Health Organization categories, with 55.8% of people and 73.1% of eyes having a presenting visual acuity of less than 3/60 and only 9.7% and 2.4% of people and eyes respectively having a good outcome (6/18 or better). None were wearing an aphakic correction, and with correction acuities improved but 42.6% of eyes were still blind (< 3/60).

Conclusions: Couching is still widely practiced in Nigeria and visual outcomes are very poor. The population needs to be made aware of the risks associated with the procedure, and services for high quality, affordable cataract surgery need to be expanded, particularly in rural areas and in the north of the country.     

A retrospective study on presbyopia onset and progression in a Hispanic population.

BACKGROUND: This study evaluates differences in age and presbyopia progression between an ethnic Hispanic and a non-Hispanic patient population. METHODS: Patient records from the Optometric Center of Los Angeles were examined retrospectively from 1998 through 2001. The first part of the study compared ages at onset and progression of presbyopia as a function of ethnicity. The second part of the study compared the amplitude of accommodation for the cohort of patients to Hofstetter's expected norms. RESULTS: A total of 332 patient records were evaluated: 61% (n = 203) Hispanic and 39% (n = 129) non-Hispanic. For an add power of +0.75 D, presbyopia developed in the reviewed Hispanic population at 39.31 years of age in comparison to development in non-Hispanics at 40.22 years. Hispanics also had a similar progression of reading add power (0.105 D/year) as compared to non-Hispanics (0.097 D/year) (t= 0.798, p = 0.43). The progression of amplitude of accommodation for the Hispanic (amplitude = 11.2 - 0.132 x age) and non-Hispanic populations (amplitude = 9.72 - 0.18 x age) (t= 0.0997, p = 0.92) were comparable, but both groups show a slower decline of amplitude when compared to Hofstetter's norms (p< 0.001). CONCLUSIONS: No statistically significant difference in the age at onset and progression of presbyopia was found between Hispanic and non-Hispanic patients; however, both groups of patients have a later onset and slower progression of presbyopia when compared to Hofstetter's norms.     

Visual impairment in a Taiwanese population: Prevalence,causes, and socioeconomic factors

PURPOSE We sought to estimate the prevalence of visual impairment among an elderly population in urban Taiwan, determine the causes of visual impairment, and gain information about certain socioeconomic factors associated with visual impairment.

METHODS A population-based survey of ocular diseases in residents aged 50 years or older was conducted in Peitou Precinct, Taipei, Taiwan. All participants underwent a comprehensive ophthalmic examination, including visual acuity measurement, using standardized protocols. Demographic data, marital status, employment status, and educational level were gathered through an interview.

RESULTS A total of 2034 participants completed the visual acuity measurements. The prevalence of visual impairment (defined as best-corrected visual acuity in the better eye <6/18) among this population was 2.75% (95% confidence intervals: 2.04%–3.46%). Three major causes of visual impairment were cataract (30.4%), high myopic macular degeneration (25.0%), and age-related macular degeneration (14.3%). In multivariate analysis, age was positively correlated with visual impairment (P < 0.001), and higher education level was associated with a significant decrease in the odds of being visually impaired (P < 0.001). No relation was found between visual impairment and sex, or marital and employment status.

CONCLUSIONS This study provides the first information about the prevalence and causes of visual impairment in Taiwan, and identifies age and educational level as the most important factors related to visual impairment. Additional educational programs should be developed to improve individual awareness of age-related ocular diseases and the availability of current ophthalmic intervention.     

Prevalence of Trachoma in Katsina State,Nigeria: Results of 34 District-Level Surveys

ABSTRACT

Purpose: To determine the local government area (LGA)-level prevalence of trachoma in all 34 LGAs of Katsina State.

Methods: A population-based prevalence survey was conducted in each LGA of Katsina State, using the Global Trachoma Mapping Project methodology. We used a 3-stage cluster random sampling strategy to select 25 households from each of 25 clusters. We examined all residents of selected households aged 1 year and older for the clinical signs of trachomatous inflammation–follicular (TF), trachomatous inflammation–intense and trichiasis, using the World Health Organization (WHO) simplified grading scheme.

Results: We examined 129,281 persons. Six LGAs had a TF prevalence ≥10%, and another six LGAs had a TF prevalence between 5% and 9.9%; all 12 require mass drug administration with azithromycin plus other interventions. The prevalence of trichiasis was ≥1.0% in 13 LGAs, and there is a need to perform trichiasis surgery in over 26,000 persons to reach targets set by the WHO for elimination of trichiasis.

Conclusion: The prevalence of TF is generally low in Katsina state, but urgent steps must be taken to implement the full SAFE strategy (surgery, antibiotics, facial cleanliness, environmental improvement) in at least 12 LGAs while also stepping up efforts to provide community-based trichiasis surgery throughout the whole state, in order to make trachoma elimination by 2020 a reality.     

Prevalence of refractive error,presbyopia, and unmet need of spectacle coverage in a northern district of Bangladesh: Rapid Assessment of Refractive Error study

Purpose: To determine the prevalence of refractive error (RE), presbyopia, spectacle coverage, and barriers to uptake optical services in Bangladesh.

Method: Rapid assessment of refractive error (RARE) study following the RARE protocol was conducted in a northern district (i.e., Sirajganj) of Bangladesh (January 2010–December 2012). People aged 15–49 years were selected, and eligible participants had habitual distance and near visual acuity (VA) measured and ocular examinations were performed in those with VA<6/18. Those with phakic eyes with VA <6/18, but improving to ≥6/18 with pinhole or optical correction, were considered as RE and people aged ≥35 years with binocular unaided near vision of <N8 were considered presbyopic.

Result : A total of 3,043 people were examined, of which 143 had RE (4.7%, 95% CI: 3.9–5.5). Among people aged ≥35 years (n = 1402), 869 had presbyopia (62.0, 95% CI: 59.4–64.5). Spectacle coverage for RE and presbyopia were 13.3% (95% CI 7.7–18.9) and 3.2% (95% CI 2.2–4.6), respectively. “Unaware of the problem” was the main reason for not utilizing any optical services among the people with RE (92.8%) and presbyopia (89.5%). Extrapolating the survey findings to the 2011 national census data, the magnitude of RE among people aged 15–49 years in Bangladesh is estimated to be 3,493,980 people (95% CI 2,899,260–4,088,700), of whom 3,029,280 people do not use any spectacles.

Conclusion : The burden of RE and presbyopia is substantial in Bangladesh. Improving awareness and availability of refraction services is required to correct REs and presbyopia in Bangladesh.     

Ocular hypotension in a population survey

Summary 75 people found to have low ocular tensions were examined for ocular or systemic disease which could have been the cause of hypotension. Errors of refraction or local eye disease could not be incriminated. A history of systemic disease which could possibly be associated with ocular hypotension was found in about one-quarter of those examined. Anaemia was the commonest single condition encountered. It is concluded that ocular tensions of 10 mm Hg or less may still be within the physiological range.

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Zusammenfassung 75 Fälle, bei denen während einer Massenuntersuchung niedriger intra-okulärer Augendruck gefunden wurde, wurden wiederholt untersucht. Wir haben Augenkrankheiten oder Allgemeinkrankheiten zu finden gesucht, die Ursachen des niedrigen Augeninnendruckes sein könnten; Refraktionsfehler und lokale Augenkrankheiten können nicht beschuldigt werden. Eine Systemkrankheit war in einem Viertel der Untersuchten vorhanden. Blutarmut war die häufigste Ursache, die in Betracht gezogen werden konnte. Zusammenfassend kann gesagt werden, dass ein Augeninnendruck von 10 mm Hg oder weniger noch als physiologisch angesehen werden kann.

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Résumé 75 personnes ayant une hypotension oculaire ont été examinées pour se rendre compte, si une maladie oculaire ou générale pouvait être la cause d'une hypotension. On n'a pas pu considérer comme responsables des vices de réfraction ou une maladie oculaire locale. Chez un quart des personnes examinées il se trouvait une maladie générale qui pouvait être mise en rapport avec l'hypotension oculaire. La plus fréquente était l'anémie. On conclut qu'une tension oculaire de 10 mm Hg ou moins pourrait encore entrer dans les limites physiologiques.

     

Automatic perimetry in a population survey

Automatic perimetry was performed in 2998 eyes of 1511 subjects comprising 78% of all persons born 1907--1921 and resident in a certain small area. Unreliable or abnormal tests were repeated. The average number of tests per person was 2.25. About 90% of all tests in normal eyes were performed in less than 3 min. The screening was considered negative in 2887 eyes, incomplete in 20 eyes and positive in 91 eyes (3%). Eighteen of the positives were previously unknown glaucomatous defects. There was only one unexplained "false positive". We concluded that the method is quick, sensitive, specific and dependable. The apparatus is simple to manage and cheap to run.