Blindness and Low Vision in Germany 1993–2009

Sensory Dysfunction in Old Age

BACKGROUND

The senses serve as the crucial interface between the individual and the environment. They are subject to aging and disease processes.

METHODS

This review is based on pertinent publications retrieved by a selective search in the Medline and Cochrane Library databases.

RESULTS

Approximately 40% of persons aged 70 to 79 manifest dysfunction in at least one, and more than 25% in multiple senses. Sensory changes are accompanied by diverse comorbidities which depend on the particular sense(s) affected. The presence of sensory deficits is associated with an increased risk of developing dementia (OR: 1.49 [95% confidence interval: 1.12; 1.98] for dysfunction in a single sensory modality, 2.85 [1.88; 4.30] for dysfunction in three or more sensory modalities). The risk of developing depressive symptoms is elevated as well (OR 3.36 [2.28; 4.96]). The individual's ability to cope with the demands of everyday life is largely determined by the ability to carry out multisensory integration, in which the perceptions of the different senses are bound together. This function itself is subject to age-related changes that can be either adaptive or maladaptive; it can, therefore, serve as an indicator for pathological aging processes.

CONCLUSION

Sensory dysfunction in old age should be detected as early as possible. This implies the need for close collaboration of all of the involved disciplines. It would be desirable to develop sensory screening tests as well as a procedure for testing multisensory integration in routine clinical practice.

Schuster A, M. Elflein H, Nickels S, Schulz A, S. Wild P, E. Beutel M, Blettner M, Münzel T, J. Lackner K, Pfeiffer N. The Prevalence of Visual Impairment in the Adult Population

BACKGROUND

The distribution of visual impairment is an indicator of the health status of the population and for the frequency of diseases of the eye.

METHODS

The Gutenberg Health Study (GHS) is a population-based cohort study in Germany concerning adults aged 35 to 74. 15 010 subjects from the Mainz-Bingen region underwent general medical and ophthalmological examination, with measurement of the distance-corrected visual acuity in each eye separately. As per the World Health Organization criteria, visual impairment was defined as an acuity below 0.3 in the better eye, and blindness as an acuity below 0.05. All patients who were found to be visually impaired or blind underwent further individual study with clinical history-taking, split-lamp examination, and fundus photography.

RESULTS

Data from 14 687 subjects were evaluated. The mean age of the partici- pants was 55.0 years (standard deviation, 11.1 years). The prevalence of visual im- pairment was 0.37% (95% confidence interval [0.28; 0.49]) (n = 55) and was higher in women (0.44%) than in men (0.31%). Blindness was present in 0.05% [0.03; 0.11] (n = 8) of the subjects. The prevalence of visual impairment from age 65 on- ward was 0.79%, three times higher than in the younger age groups. 54.5% of the visually impaired subjects had multiple underlying ophthalmological pathologies.

CONCLUSION

The causes of visual impairment are manifold. Loss of vision is often the combined effect of multiple pathological factors. The etiology of visual impair- ment is thus a more complex matter than is commonly assumed.

Paediatric vision screening by non-healthcare volunteers: evidence based practices

BACKGROUND

The purpose of this study was to test the sensitivity and specificity of eight undergraduate volunteer examiners conducting vision screening tests in a community setting, in order to determine if non-eye care professionals were able to be trained to an appropriate level of skill.

METHODS

Eight undergraduate volunteer examiners were trained to conduct vision screening tests to address a gap in pediatric community eye care. Phase I of the study was implemented in the pediatric ophthalmology clinic, and phase II was conducted in nine local schools. Phase I consisted of 40 h of training for each volunteer regarding specific vision tests. Phase II consisted of screening children at nine local schools.

RESULTS

A total of 690 children from nine local schools were screened by both the volunteer examiners and the optometrist during the course of this study. Volunteer examiners had a screening sensitivity of 0.80 (95%CI 0.66-0.90) and screening specificity of 0.75 (95%CI 0.71-0.78) when compared to the study optometrist. The overall accuracy of volunteer examiners was 75%. The resulting positive likelihood ratio was 3.24 (95%CI 2.6-3.9), indicating that a child with vision impairment was 3.2 times more likely to fail the vision test performed by the volunteer examiners compared to a child with no vision impairment.

CONCLUSIONS

Non-healthcare professionals can be trained to an acceptable degree of accuracy to perform vision screening tests on children, which may assist in mitigating existing gaps in paediatric eye care.

Assessing accuracy of non-eye care professionals as trainee vision screeners for children

OBJECTIVE

To determine the level of agreement between non-eye care trainees and a trainer (ophthalmologist) in a vision screening program.

DESIGN

Prospective, observational study carried out in 3 phases (Phase I-III).

PARTICIPANTS

Study population included 1228 children, aged 6-14 years, at 5 elementary schools in the city of Hamilton.

METHODS

In Phase I, 1228 children were screened by the trainee screeners, of which 273 children failed the vision testing. Of these 273 children, 170 consented to enrolment into Phase II and were examined by an ophthalmologist, who confirmed that 105 of these children were true positives. On retesting (Phase III), the ophthalmologist passed 158 of the 163 randomly selected children who passed in Phase I.

RESULTS

Overall, trainee screeners had a sample sensitivity of 95.5% and sample specificity of 70.8% in detecting children who should fail vision screening. When we used the positive and negative prediction values obtained, 198 of the 1228 children had vision impairment-providing an estimated prevalence of 16.1%, or 161 children per 1000 population.

CONCLUSIONS

Non-eye care professionals can be trained to an acceptable degree of accuracy to perform certain vision screening tests on children. Such screening methods may be a useful approach to address existing gaps in provision of eye care for many Canadian children, thereby ensuring that all children receive timely vision screening.

Effect of reduced visual acuity on precision of two-dimensional tracing movements

PURPOSE

We intended to assess consequences of reduced visual acuity for performance in a natural simple motor task (tracing) using objective kinematic performance measures. Specifically, we intended to elucidate the kind of relationship between the task performance and best corrected binocular visual acuity and to determine the threshold of visual acuity when task performance starts to deteriorate.

METHODS

Ninety-five individuals with different best corrected visual acuity participated in the study (age 49±12 years, mean±SD, 27 men and 68 women). The participants manually traced maze-like visual patterns of different spatial complexity presented on the screen of a portable notebook computer using Clinical Kinematic Assessment Tool software. Tracing error was computed as performance measure in each trial with a spatial pattern matching technique - rigid point set registration method.

RESULTS

The segmented linear regression analysis showed that the relation between visual acuity and tracing errors was best described with a regression function having a break point between two data segments. Tracing performance was unaffected by values of visual acuity below 0.2 on logMAR scale, but when logMAR values increased above this critical limit (i.e. when visual acuity is further reduced), tracing errors linearly increased. The rate of the increase of the tracing error correlated with the complexity of visual stimulus shape.

CONCLUSION

Testing of fine motor functions with objective kinematic measures during visuomotor tasks may help differentiating between actual effects of reduced visual acuity on eye-hand coordination in individuals with similar levels of impairment of visual acuity.

Danish Rural Eye Study: Epidemiology of Adult Visual Impairment

PURPOSE

To examine the frequency and causes of visual impairment (VI) in a select population of Danish adults.

METHODS

A total of 3843 adults aged 20-94 years from the Danish General Suburban Population Study (GESUS) were included in the population-based, cross-sectional ophthalmological study, Danish Rural Eye Study (DRES). All DRES participants received a comprehensive general health examination preceding their eye examination, including measurement of best-corrected visual acuity (BCVA) for each eye, bilateral 45° retinal fundus photographs and further ophthalmological examination where indicated.

RESULTS

Overall, 3826 of 3843 participants (99.6%) had bilateral visual acuity measurements. The overall frequency of VI (BCVA <20/40 in the better-seeing eye) was 0.4% (95% confidence interval, CI, 0.2-0.7%; n = 15) among all DRES participants, 0.6% (95% CI 0.3-1.0%; n = 15) among participants >50 years and 3.7% (95% CI 2.1-6.5%; n = 11) in participants >80 years. The primary causes of VI in the better-seeing eye were age-related macular degeneration (AMD) in 46.7% (7/15) and cataract in 26.7% (4/15). A total of 43.3% (n = 115) of participants >80 years were pseudophakic in one or both eyes. The frequency of diabetes (HbA1c ≥ 48 mmol/mol or self-reported diagnosis) was 5.9% (n = 227), including 1.3% (n = 51) newly diagnosed in the GESUS. Of participants determined to have VI due to exudative AMD, 50% had received anti-vascular endothelial growth factor (VEGF) treatment.

CONCLUSION

We report a relatively low frequency of VI among Danish adults over 59 years of age compared with that observed 10-15 years ago, which is both consistent with other recent Scandinavian studies and reflective of our relatively healthy and mobile population sample.

[Increase in examinations for cataracts, glaucoma, diabetic retinopathy and age-related macular degeneration : Comparative cross-sectional study between 2010 and 1997 in ophthalmological practices]

BACKGROUND

The importance of the four most commonly occurring vision-threatening diseases, age-related macular degeneration (AMD), glaucoma, diabetic retinopathy and cataract in ophthalmological practices has changed due to demographic developments, medical progress and transference of inpatient treatment to the outpatient area of private practice.

METHODS

In the fourth quarter year of 2010 a survey of 15,125 patients (approximately 10%) from 96 private ophthalmology practices (mean 149 patients per ophthalmologist, range 45-376) was carried out. The results for the four most commonly occurring vision-threatening diseases were compared with the result from a previous survey carried out for the fourth quarter year of 1997.

RESULTS

Compared to 1997 there was an increase in the age-adjusted proportion of examinations in 2010 for cataracts by 29 %, for glaucoma by 21 %, for diabetic retinopathy by 39 % and for vitreoretinal diseases by 19 %. The number of AMD examinations in the age group over 70 years old showed a particularly high increase.

CONCLUSIONS

The number of patients examined for the four most commonly occurring vision-threatening diseases increased from 1997 to 2010 not only in absolute numbers but also in relation to age. In the future financial and personnel resources must be made available for the early and guidelines-conform detection, diagnostics and therapy by ophthalmologists.

The prevalence and causes of visual impairment and blindness among older adults in the city of Lodz, Poland

To investigate the prevalence and causes of visual impairment and blindness in a sample of Polish older adults. The study was designed in a cross-sectional and observational manner. Data concerning the vision status were assessed in 2214 eyes from 1107 subjects of European Caucasian origin; most of whom live in the city of Lodz, in central Poland. Visual impairment was defined as distance visual acuity <20/40 in the worse-seeing eye. Low vision was defined as best-corrected visual acuity (BCVA) <20/40 but >20/200 in better-seeing eye, and blindness was defined as BCVA ≤20/200 in both eyes (United States criteria). Visual impairment was found in 27.5% subjects in the worse-seeing eye. Multiple regression analysis showed that increasing age (OR 0.98, 95% CI 0.97-0.99) and female gender (OR 1.47, 95% CI 1.11-1.93) were independent risk factors. No association was found between visual impairment and socioeconomic status of subjects. Noncorrectable visual impairment was found in 7.0% of subjects, including 5.2% of subjects with unilateral and 1.8% of subjects with bilateral visual impairment. Low vision and blindness accounted for 1.3% and 0.5%, respectively, and were only associated with older age (OR 1.05, 95% CI 1.02-1.10). Retinal diseases represented the major cause of noncorrectable visual impairment and accounted for more than half of causes of blindness. Provision of appropriate refractive correction improves visual acuity in 75% subjects presenting with visual impairment. Retinal diseases are a major cause of noncorrectable visual impairment and blindness in this older population.

[Outcomes and health services research in ophthalmology]

This article describes the role of outcomes and health services research in the field of ophthalmology in Germany. First, the need for more information and data on the performance of ophthalmic care in Germany is explored. The concept, goals and methods of outcomes and health services research are explained and illustrated by examples of already existing research projects in ophthalmology. Future topics for research projects are highlighted. The article also describes how the field of outcomes and health services research can become a more important part within the scientific ophthalmological community in Germany.

Problems and perspectives of ophthalmic research in Germany: results from a national survey

PURPOSE

To identify and describe the most relevant obstacles to carrying out ophthalmic research in Germany.

METHODS

Two research methods were used to assess current problems in ophthalmic research. First, 55 expert interviews were conducted with major stakeholders in ophthalmic research, and key problems were identified. An online questionnaire was then sent to 3,080 German ophthalmologists, of whom 927 responded by evaluating the current research situation within ophthalmology in Germany. We devised a score to rank areas of concern by multiplying the responders' rate, ranging between -3 ('I disagree completely') and +3 ('I fully agree'), with the percentage of response frequencies. The maximum possible score was 300.

RESULTS

The lack of opportunities to combine clinical work and research (score: 231.8) as well as unattractive career perspectives (175.7) were identified as the most relevant problems. Further barriers were difficulties in acquiring research funds (155.7), organizational problems at the local level (143.7) and a lack of support for women (24.1; among women: 122.3). Potential improvement was expected in particular from exemption from clinical work for scientific purposes; this was found to be more appealing than more prestigious awards for research achievements. A widely held position was that research projects should focus more closely on common eye diseases, and that vision research needs a more prominent profile among politicians and in the public arena.

CONCLUSION

Our findings may help to initiate improvements in both research performance and outcomes.

[Preservatives from the perspective of glaucoma surgery]

Trabeculectomy is still the gold standard in the surgical treatment of glaucoma patients. Development of a bleb is the primary goal of this procedure and the conjunctival status is therefore decisive. Only a good functioning bleb renders good intraocular pressure (IOP) control. Scar tissue formation leads to bleb failure which is quite common despite the use of antiproliferative agents, such as mitomycin C and 5 fluoruracil. Wound healing is important and is influenced and impaired by the chronic use of topical antiglaucoma drugs. Therefore, complete abstinence is recommended from 4-6 weeks prior to a planned trabeculectomy; however, it seems mandatory to completely abolish preservatives such as drops containing benzalkonium chloride to enhance trabeculectomy success rates.

Current status of epibulbar anti-glaucoma drainage devices in glaucoma surgery

BACKGROUND

The term "glaucoma" covers a heterogeneous group of progressive optic neuropathies that are accompanied by characteristic visual-field defects. Primary open-angle glaucoma, the most common type, progresses insidiously and causes blindness if untreated. All current forms of treatment aim at lowering the intraocular pressure (IOP) in patients whose IOP is elevated. The implantation of anti-glaucoma drainage systems is one of the available options for surgical treatment.

METHODS

This review is based on pertinent literature retrieved by a selective search, including glaucoma treatment guidelines from Germany and abroad.

RESULTS

A paradigm shift is currently underway regarding the indications for the implantation of anti-glaucoma drainage systems. Trabeculectomy (a "fistulating" operation in which the aqueous humor is led out of the eye under the conjunctiva) is still considered the surgical gold standard, but drainage systems have been implanted with increasing frequency in recent years. Studies have shown that these systems are more likely to be beneficial the earlier they are implanted in the course of the patient's disease. Five-year follow-up data from the randomized, multicenter Tube Versus Trabeculectomy (TVT) study have now revealed that anti-glaucoma drainage systems are equivalent to trabeculectomy with respect to long-term IOP reduction, complication rates, and absolute and relative clinical success rates.

CONCLUSION

Glaucoma is a major clinical and socio-economic problem whose surgical treatment increasingly involves the implantation of anti-glaucoma drainage systems.

Blindness and visual impairment in Germany: a slight fall in prevalence

BACKGROUND

Some 70% of all cases of blindness in Germany are due to diseases of old age. As the population at large is aging, the prevalence of blindness and visual impairment would be expected to rise. To assess this, we studied prevalence trends in Germany over the past three decades.

METHODS

We calculated the age- and sex-standardized prevalence of blindness in Germany using data from the archive of the blind registry of the Rhineland Regional Council (Landschaftsverband Rheinland, LVR) for the years 1978 to 2006. We then validated the findings with the aid of data on blindness and visual impairment from the Statistics on Severe Disability (Schwerbehindertenstatistik, SBS) that are published periodically by the German Federal Statistical Office.

RESULTS

The number of registered blind persons in the Rhineland increased from 10,665 in 1978 to 12,706 in 1987 and 15,766 in 1997, but it changed little thereafter, remaining at 15,725 in 2006. There was a corresponding trend in the prevalence of blindness in the Rhineland, which rose from 116.8 to 165.6 per 100,000 persons from 1978 to 1997 but was roughly the same, at 163.1 per 100,000 persons, in 2006. The SBS data on blindness and visual impairment reveal a decline in prevalence from 392 to 372 per 100,000 persons between 1987 and 2005. The standardized prevalence rates for blindness and visual impairment in Germany have been declining slowly since about 1997.

DISCUSSION

Blindness and visual impairment have become slightly less common in Germany, even though the population is aging. This may be due, at least in part, to better eye health care.