The prevalence and incidence of visual impairment in people of age 20-59 years in industrialized countries: a review

[Incidence and causes of visual impairment in the district of Mahdia, in east Tunisia: Retrospective study of 1487 cases]

OBJECTIVE

To study socio-demographic characteristics and main causes related to visual impairment (VI) as a function of age bracket and to analyze their trends over time in the district of Mahdia.

METHOD

A retrospective review was performed on 1487 cases of visual impairment registered with the social authorities in Mahdia, between 1980 and 2013. The social, demographic, vision exam findings and causes were ascertained and analyzed in an SPSS database. Incidence rates of VI and blindness due to various causes were calculated based on the demographic data from the NSI to estimate the time trends using the general linear regression model and Spearman correlation.

RESULTS

Analyses included 1487 participants with a median age of 47 years, 40.6% of cases were aged under 45 years. Children accounted for 11.1% (165 patients), while age was between 16 and 45 years in 29.5% (439 patients), between 46 and 65 years in 31.5% (469 patients) and greater than 65 years in 27.8% (414 patients). The sex-ratio (M/F) was 1.78. Socially, 51% came from rural areas, 62% were illiterate, and 84% were unemployed. We observed blindness in 70% of participants and low vision in 30%. In children, the causes were dominated by congenital cataract and congenital glaucoma, each present in 31 children (18.8%). Between 16 and 45 years, glaucoma and hereditary dystrophies of the retina were found in 62 and 61 patients respectively (14% each). For age between 46 and 65 years, trachoma was responsible for 19.8% of cases of VI, glaucoma in 15.8% and cataract in 15.1%. Beyond 65 years, glaucoma accounted for 30.7% of the causes of VI and cataract 27.8% of cases. Trend analysis shows a significant increase in the incidence rate of visual impairment with an average of 12% per year (P=0.001). The mean age increased by 46% (P=0.003). Trachoma increased by 118% (P<0.0001) between 1980 and 1990, then declined by 42% (P=0.0013) between 1991 and 2013. Incidence of VI significantly increased by 4% for cataract (P=0.001), 23% (P=0.001) for glaucoma and 20% (P=0.02) for diabetic retinopathy, while VI related to refractive errors and AMD showed no significant change.

CONCLUSION

Advanced age, lower educational and socio-economic status were associated with bilateral VI. Age related eye problems are the main causes of VI, and their incidence is tending to increase. Public health policies and procedures should be targeted to risk related populations and age-related diseases in order to control the incidence of visual impairment and avoid its consequences.

Vision impairment and dual sensory problems in middle age

PURPOSE

Vision and hearing impairments are known to increase in middle age. In this study we describe the prevalence of vision impairment and dual sensory impairment in UK adults aged 40-69 years in a very large and recently ascertained data set. The associations between vision impairment, age, sex, socioeconomic status, and ethnicity are reported.

METHODS

This research was conducted using the UK Biobank Resource, with subsets of UK Biobank data analysed with respect to self-report of eye problems and glasses use. Better-eye visual acuity with habitually worn refractive correction was assessed with a logMAR chart (n = 116,682). Better-ear speech reception threshold was measured with an adaptive speech in noise test, the Digit Triplet Test (n = 164,770). Prevalence estimates were weighted with respect to UK 2001 Census data.

RESULTS

Prevalence of mild visual impairment (VA >0.1 logMAR (6/7.5, 20/25) and ≥0.48 (6/18, 20/60)) and low vision (VA >0.48 (6/18, 20/60) and ≥1.3 (6/120, 20/400)) was estimated at 13.1% (95% CI 12.9-13.4) and 0.8% (95% CI 0.7-0.9), respectively. Use of glasses was 88.0% (95% CI 87.9-88.1). The prevalence of dual sensory impairment was 3.1% (95% CI 3.0-3.2) and there was a nine-fold increase in the prevalence of dual sensory problems between the youngest and oldest age groups. Older adults, those from low socioeconomic and ethnic minority backgrounds were most at risk for vision problems.

CONCLUSIONS

Mild vision impairment is common in middle aged UK adults, despite widespread use of spectacles. Increased likelihood of vision impairment with older age and with ethnic minorities is of concern given ageing and more ethnically diverse populations. Possible barriers to optometric care for those from low socioeconomic and ethnic minority backgrounds may require attention. A higher than expected prevalence of dual impairment suggests that hearing and vision problems share common causes. Optometrists should consider screening for hearing problems, particularly among older adults.

Peripheral autofluorescence and clinical findings in neovascular and non-neovascular age-related macular degeneration

PURPOSE

To characterize peripheral fundus autofluorescence (FAF) abnormalities in patients with age-related macular degeneration (AMD), correlate these with clinical findings, and identify risk factors associated with these FAF abnormalities.

DESIGN

Clinic-based, cross-sectional study.

PARTICIPANTS

A total of 119 consecutive patients: 100 patients with AMD (200 eyes) and 19 patients without AMD (38 eyes).

METHODS

In a prospective study performed at the Doheny Eye Institute, University of Southern California, widefield 200-degree FAF and color images were obtained by the Optos 200Tx Ultra-Widefield device (Optos, Dunfermline, Scotland) using a standardized imaging protocol. The FAF images were captured centered on the fovea, and additional images were captured after steering the field of view inferiorly and superiorly. All FAF and color images were graded independently by 2 masked ophthalmologists with respect to the presence, location, extent, and type of peripheral (defined as outside the central 30 degrees) FAF abnormality.

MAIN OUTCOME MEASURES

Presence and type of peripheral FAF abnormalities.

RESULTS

Peripheral FAF abnormalities were evident in 164 eyes (68.9%), with several distinct FAF patterns identified: granular (46.2%), mottled (34.0%), and nummular (18.1%). A 90% concordance of FAF patterns was observed between both eyes. Abnormal FAF occurred more frequently in neovascular compared with non-neovascular AMD or normal eyes (86% vs. 72.8% vs. 18.4%, respectively, P<0.001). Significant risk factors for peripheral FAF abnormalities were AMD type (neovascular AMD odds ratio [OR], 12.7 and non-neovascular AMD OR, 6.2 compared with normal eyes, P<0.001), older age (OR, 6.5; 95% confidence interval [CI], 2.4-17.8; P<0.001 for the oldest quartile compared with the youngest), and female sex (OR, 4.1; 95% CI, 1.9-8.9; P<0.001). Clinical features on color photography were detected in 174 eyes (73.1%): peripheral drusen (51.7%), retinal pigment epithelium (RPE) depigmentation (34.9%), RPE hyperpigmentation (branching reticular pigmentation) (22.7%), and atrophic patches (16.8%). There was a high correlation between specific FAF and clinical findings: granular FAF with peripheral drusen (P<0.001) and mottled FAF with RPE depigmentation (P<0.001).

CONCLUSIONS

Several distinct patterns of peripheral FAF abnormalities were observed in 68.9% of patients, with AMD type, female sex, and age being independent risk factors. The peripheral FAF patterns correlate strongly with specific clinical features seen in eyes with AMD.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

[Prevalence and burden of visual impairment in Catalonia, Spain]

The aim of this work is to determine the prevalence of visual impairment in Catalonia and analyze inequalities in vision. Cross sectional study in the population having ≥ 15 years of age (7,881 men and 8,045 women) based on data from the Encuesta de Salud de Cataluña 2006. Logistic regression models were used to calculate the adjusted odds ratio by age, civil state, level of studies, income and working situation with a confidence interval (CI) of 95%. A 4.7% (CI 95% 4.4-5.0) of the population of Catalonia, a 5.3% of female (CI 95% 4.8-5.8), and 4.1% of men (CI 95% 3.7-4.5) state that they have poor vision. The most unfavourable situations of self-reported poor vision by the Catalan population correspond to the elderly and women with lower levels of both studies and income.

Blindness and low vision in The Netherlands from 2000 to 2020-modeling as a tool for focused intervention

PURPOSE

To estimate the magnitude and causes of blindness and low vision in The Netherlands from 2000 to 2020.

METHODS

Recent population-based blindness surveys in established market economies were reviewed. Age and gender specific prevalence and causes of blindness and low vision were extracted and calculated for six population subgroups in The Netherlands. A mathematical model was developed to relate the epidemiologic data with demographic data for each subgroup for each year between 2000 and 2020.

RESULTS

In 2008 an estimated 311,000 people are visually impaired in The Netherlands: 77,000 are blind and 234,000 have low vision. With the current intervention the number may increase by 18% to 367,000 in 2020. Visual impairment is most prevalent among residents of nursing homes and care institutions for the elderly, intellectually disabled persons and people aged 50+ living independently. Of all people with visual impairment 31% is male (97,000) and 69% female (214,000). More than half of all visual impairment (56%; 174,000 persons) is avoidable. A variation of around 20% might be applied to the numbers in these estimates.

CONCLUSIONS

The aim of VISION 2020: The Right to Sight to reduce avoidable visual impairment is also relevant for developed countries like The Netherlands. Vision screening and awareness campaigns focusing on the identified risk groups can reduce avoidable blindness considerably. Regular updates of the model will ensure that the prognoses remain valid and relevant. With appropriate demographic data, the model can also be used in other established market economies.

Prevalence and Causes of Blindness & Low Vision; Before and Five Years After ‘VISION 2020’ Initiatives in Oman: A Review

BACKGROUND

A prevalence survey of blindness and low vision was conducted in Oman in 2005. Here, we present the prevalence and determinants of blindness and low vision among the population >or= 40 years of age. The results are then compared with those of the survey in 1997 and the changes following the 'VISION 2020' initiatives are assessed.

METHODS

The survey covered 24 randomly selected clusters (75 houses in each). Teams assessed the distance vision of subjects while wearing glasses. The ophthalmologists examined the anterior segment and fundus to determine the causes of disability. The visual field was tested in those suspected of glaucoma. The prevalence rates of blindness (< 3/60 on presentation), legal blindness (< 6/60) and low vision (< 6/18) were calculated. The data from the 1997 survey was then analyzed to obtain similar rates in the population >or= 40 years of age.

RESULTS

The prevalence of blindness was 8.25% (95% CI 7.14-9.36) in the >or= 40 year-old population in 2005. The rate would be 6.95% (95% CI 5.92-7.98) if blindness were defined as vision with best possible correction. The prevalence of legal blindness and low vision were 12% and 45.12%, respectively. In the 1997 survey, the prevalence of blindness in same age group was 7.23% (95% CI 5.91-8.55). Between the two surveys, the prevalence of blindness due to corneal pathology declined from 1.9% to 1.1% but that of blindness due to unoperated cataract increased from 1.8% to 2.3%.

CONCLUSIONS

The rate of disability has declined but the number of blind people has increased in Oman. The causes of blindness have changed from communicable/avoidable eye diseases to non-curable/chronic eye diseases, and the number with visual disabilities has increased. An increasing number of operations for cataract and improvements in the care for glaucoma and diabetic retinopathy are recommended.

Symptom burden in persons with spinal cord injury

OBJECTIVE

To determine (1) the frequency, severity, and reported course of 7 symptoms in persons with spinal cord injury (SCI) and (2) the association between these symptoms and patient functioning.

DESIGN

Postal survey.

SETTING

Community.

INTERVENTION

A survey that included measures of the frequency, severity, and recalled course of pain, fatigue, numbness, weakness, shortness of breath, vision loss, and memory loss, as well as a measure of community integration and psychologic functioning was mailed to a sample of persons with SCI. One hundred forty-seven usable surveys were returned (response rate, 43% of surveys mailed).

MAIN OUTCOME MEASURES

The frequency and average severity of each symptom was computed, and the frequencies of each type of reported course were noted. Analyses estimated the associations among the symptoms, and between symptom severity and measures of patient functioning.

RESULTS

The most common symptoms were pain, weakness, fatigue, and numbness. All symptoms were reported to remain the same or to get worse more often than they were reported to improve once they began. Pain, weakness, fatigue, and memory loss were the symptoms most closely associated with patient functioning.

CONCLUSIONS

Patients with SCI must deal with a number of secondary complications in addition to any disability caused by the injury itself. Of 7 symptoms studied, pain, weakness, and fatigue appeared to be most common and most closely linked to patient social and mental health functioning. Research is needed to identify the causal relationships between perceived symptoms and quality of life in patients with SCI and to identify effective treatments for those symptoms shown to impact patient functioning.

Optometric practice in Norway: a cross-sectional nationwide study

PURPOSE

To describe optometric practitioners and their encountering patients.

METHODS

All members of the Norwegian Association of Optometrists working in the community (n = 761) were invited to participate in a questionnaire survey; questionnaire responders (n = 508) were asked to take part in a practice registration. Data collection was carried out between November 2004 and May 2005 using a questionnaire and a practice registration form.

RESULTS

Five hundred and eight optometrists responded to the questionnaire; of these 212 participated in the practice registration, in which 4052 patient encounters were recorded. All optometrists reported taking patient history in the areas of vision and ocular health; 55% asked questions about general health for all patients. More than 80% collaborated with general practitioners and ophthalmologists. The patient encounters were with 1699 men and 2216 women; 60% of patients were aged 45 years or older. Patients reported a history of ocular disease and other conditions of relevance for ocular health in 12% and 17% of encounters, respectively. One per cent had low vision [best corrected visual acuity (BCVA) < 0.33] and 2% were visually impaired (BCVA < 0.5). Ophthalmoscopy was performed for 88% of patients; dilated fundus examinations were carried out for 2%; clinical findings of cataract were reported for 11%; and retinopathy was suspected in 3%. Six per cent of patients were referred to a general practitioner or ophthalmologist.

CONCLUSION

Optometrists generally collaborate with general practitioners and ophthalmologists. They take history, investigate and assess patients with ocular problems. A significant number of patients had primary or secondary ocular disease. This illustrates the role of optometrists as healthcare workers.

High Myopia Progression and Visual Impairment in a Nonselected Group of Danish 14-Year-Olds Followed Over 40 Years

PURPOSE

The purpose of this study was to document the adult age progression of myopia and the incidence of visual impairment in a representative sample of Danish adolescents with high myopia.

METHODS

This study consisted of a scheduled regular ophthalmic follow-up over 40 years of 39 otherwise unselected Copenhagen 14 year olds with uni- and bilateral myopia of at least -6 D, as screened from a 1948 birth-year school cohort comprising 9243 pupils. Thirty-six of the 39 had satisfactory refractive and corrected visual acuity data for a longitudinal analysis.

RESULTS

Myopia progression for the full period ranged from 0 to 14 D, and the peak myopia value increased from -14 to -26 D. The mean progression from age 16 to 26 years was 2.09 D, and from age 26 and on it was 1 D. Using both eyes and relevant correction, at the preliminary end point of 54 years, 32 of the 36 had a corrected visual acuity (VA) of 0.5 or better. Four had a corrected VA of < or = 0.3, but the visual loss was partly explained by other eye pathology. Significant visual reduction in single eyes mainly affected the subgroup of eyes with unilateral high myopia (n = 9).

CONCLUSIONS

With only a slight overrisk recorded as associated with high myopia (in three or four of 36 subjects), the adult visual prognosis for working age appeared better than usually claimed. There seems to be a correlation between degree of myopia at age 14 and consecutive visual loss, but it was not possible to identify subjects at high risk at that early age.