The projected increase in glaucoma due to the aging population in Austria from 2001 to 2031: results based on data of the Salzburg-Moorfields Collaborative Glaucoma Study.

PURPOSE: The aim of this study is to present the projected increase in definite primary open angle glaucoma (POAG) and related diseases in Austria from 2001 to 2031. METHODS: The present work is based on two data sources: population projections in Austria and detection rates of the Salzburg-Moorfields Collaborative Glaucoma Study for Austrians in the age groups 40-54 years, 55-69 years, and 70 years and above. The estimates of this glaucoma screening program are based on a total of 3419 subjects. Sensitivity analyses were applied to test the effects of higher and lower sets of prevalence assumptions on the extent of the probable projections. RESULTS: The number of Austrians with definite POAG, early POAG, POAG suspects, and ocular hypertension (OHT) is expected to increase until 2031 by 0.5%, 43.1%, and 65.6% in the three age groups specified above, respectively. The overall number of Austrians with POAG at the age of 40 or older is estimated to increase from 67,600 in 2001 to 96,400 in 2031. This corresponds to an increase of 42% from 2001 to 2031 (lower scenario: 37%, upper scenario: 47%). Similar increases are expected for individuals with early POAG, POAG suspects, and OHT. CONCLUSIONS: These projections provide an objective basis to estimate the resources that may be needed by health authorities and care providers such as ophthalmologists in the future and should help to design glaucoma blindness prevention programs or screening studies in Austria. The predicted continuous increase of Europe's older population will prove to become a challenge for public health professionals not only for diagnosis and monitoring, but also for the treatment of glaucoma.

Resource use and costs for a glaucoma screening program in Austria: an 8-year review: a cost-consequence analysis based on the Salzburg-Moorfields Collaborative Glaucoma Study.

PURPOSE: The aim of this study is to report costs, detection rates, and resources needed for detection of primary open angle glaucoma and related diseases in a glaucoma screening program in Salzburg, Austria, over a period of 8 years. METHODS: The Salzburg-Moorfields Collaborative Glaucoma Study performed a complete ophthalmologic examination on a total of 4864 subjects within a study period of approximately 8 years (98 months). The total numbers reported are total number of subjects screened at the initial examination and follow-up examinations; total working hours and estimated working hours per visit for one ophthalmologist and two medical assistants; direct costs per visit; detection rates for subjects; and corresponding costs per true positive case diagnosed with definite primary open angle glaucoma (POAG), early POAG, POAG suspect, ocular hypertension (OHT), and glaucoma artefact. RESULTS: Within the screening period of 98 months, a total of 9427 examinations and second verification checks were performed: 5466 at the initial examination, 404 at the 1-year follow-up, 815 at the 2-year follow-up, 339 at the 3-year follow-up, 225 at the 4-year follow-up, 1059 at the 5-year follow-up, 996 at the 6-year follow-up, 118 at the 7-year follow-up, and 5 at the 8-year follow-up. The total amount of time spent for screening was 23,814 working hours. We estimate the costs per visit at EUR 123 for each initial examination, EUR 28 for each second confirmation check, and EUR 95 per follow-up examination. The following detection rates were observed: definite POAG: 1.7% (95% CI: 1.3-2.2%), early POAG: 2.9% (95% CI: 2.3-3.5%), POAG suspect: 8.5% (95% CI: 7.6-9.4%), OHT: 2.2% (95% CI: 1.7-2.7%), glaucoma artefact or other causes: 5.8% (95% CI: 5.1-6.6%), normal cases: 79% (95% CI: 78-80%). CONCLUSIONS: Direct costs per visit were considerably higher than those reported in the Netherlands or the United Kingdom. If a health care provider decides to perform a glaucoma screening within this setting, the costs for the detection of a new case are EUR 7250 for definite POAG, EUR 4250 for early POAG, EUR 1450 for POAG suspect, EUR 5600 for OHT, EUR 2100 for glaucoma artefact case, and EUR 156 for a normal case.

[Comparison of central corneal thickness in patients participating in a glaucoma screening programme and those who were examined in the glaucoma unit]. / Vergleich der mittleren zentralen Hornhautdicke bei Patienten eines Glaukomvorsorgeprogramms und ambulanten Glaukompatienten.

BACKGROUND: The aim of this study was to compare central corneal thickness (CCT) and intraocular pressure in patients participating in a glaucoma screening programme and patients who were examined in the glaucoma unit. MATERIALS AND METHODS: 406 patients of a glaucoma screening programme (Salzburg-Moorfields collaborative glaucoma study) were included in this study. In addition a group of 406 patients who were admitted to the glaucoma clinic for a detailed glaucoma examination was included (outpatient clinic group). In all participants central corneal thickness (CCT) was measured and possible relations of CCT within the study groups were statistically analysed. RESULTS: In the population screening group the mean central corneal thickness in normal subjects was 536+/-4.3 microm, in patients with ocular hypertension (OHT) 552+/-5.7 microm, patients suffering from a normal tension glaucoma (NTG) showed a mean CCT of 534+/-14.2 microm and those with primary open angle glaucoma (POAG) had a value of 521+/-17.9 microm. In the 'outpatient clinic group' the OHT subgroup had a mean CCT of 553+/-6.8 microm, the NTG subgroup of 529+/-26.5 microm and the one with POAG had a mean of 527+/-19.8 microm. In addition, CCT was measured in all glaucoma patients whose "partner" eye was healthy (544+/-5 microm) and included in this study as part of the normal subgroup. In both groups (screening group and outpatient group), CCT was significantly higher in OHT patients than in normals. In contrast, no statistically significant difference between normals and NTG or POAG patients was detected. Intraocular pressure was significantly lower in the screening groups than in the other ones. CONCLUSIONS: Our data confirm the previously published results concerning OHT and healthy subjects. In this study no significant difference between NTG or POAG subjects and normal eyes was detected. The lower IOP in the screening population can be explained by the fact that patients contacting the screening program are self selected whereas patients of the glaucoma unit are admitted by practising ophthalmologists and are, therefore, rather advanced cases or carrying special risk factors.

[The 'cup-to-disc ratio': a comparison of TopSS, HRT II and subjective findings]. / Die 'Cup-to-Disk Ratio': Ein Vergleich von TopSS, HRT II und subjektiver Befundung.

PURPOSE: One of the major shortcomings of longitudinal studies is the fact that instruments and technologies which were used at the beginning of the sampling might be replaced by others during the course of the study. The aim of the present work is to evaluate the relationship of optic disk parameters assessed with different methods and to test statistical possibilities of transforming these parameters into each other. PATIENTS AND METHODS: The 'cup-to-disc ratio', the 'total disc area' and the 'neuroretinal rim area' of the human optic nerve of 131 eyes of 66 patients participating in the Salzburg-Moorfields Collaborative Glaucoma Study were assessed with two different laser scanning methods (TopSS and HRT II. The 'cup-to-disc ratio' was also determined subjectively by ophthalmologists of the glaucoma department. To compare the three data sets, the method of Bland-Altman, paired t-tests, as well as regression analyses were applied. RESULTS: The 'cup-to-disc ratios' were: HRT II(R): 0.26 (95 % CI: 0.23 - 0.28), subjective assessment of 'cup-to-disc ratio': 0.33 (0.30 - 0.36) and TopSS: 0.43 (0.40 - 0.46). All three results are statistically significantly different (pairwise comparisons, p < 0.00001 each). Bland-Altman analysis shows that the differences of both objective methods exceed a magnitude that can be accepted for clinical purposes. The regression analyses reveal that the slope parameters are significantly different from 1.0. No regression models could be found with sufficiently small differences. DISCUSSION: There are significant differences in the 'cup-to-disc Ratios' observed between the three methods. Therefore the application of a 'correction factor' cannot be advocated. Although such factors allow the means of the samples to agree, the differences of individual measurements still remain too large, to be useful for practical purposes.

[On the relationship between age and prevalence and/or incidence of primary open-angle glaucoma in the "Salzburg-Moorfields Collaborative Glaucoma Study"]. / Uber den Zusammenhang zwischen Lebensalter und Prävalenz sowie Inzidenz des primären Offenwinkelglaukoms in der "Salzburg-Moorfields-Collaborative-Glaucoma"-Studie.

BACKGROUND: It is the aim of this study to describe both the relationship between age and prevalence as well as age and 5-year incidence of primary open angle glaucoma (POAG) for a homogeneous population cohort. The result of the regression model for the prevalence are compared with the models of Tuck-Crick and Quigley-Vitale. In addition, estimations for the number of 5-year incidence cases of POAG are provided for individuals at the age of 40-80 years in Austria for the years in 2001-2006, 2010-2015, 2020-2025 and 2030-2035. PATIENTS AND METHODS: The "Salzburg Moorfields Collaborative Glaucoma Study" (SMCGS) is embedded in a government-supported glaucoma blindness prevention programme in Salzburg county, Austria, which is designed for a screening and follow-up period of at least 10 years. Each subject receives a complete ophthalmological examination. In total, the findings of 853 subjects are analysed and evaluated applying the guidelines of the European glaucoma society. RESULTS: The results of the regression analysis for the prevalences are in good agreement with the models of Tuck-Crick and Quigley-Vitale. The best correlation was found for individuals between 40 and 80 years of age. The 5-year incidences increase is statistically significant (p < 0.001) with increasing age: the 5-year incidences of individuals at the age of 40, 50, 60, 70 and 80 years are 0.07 % (95 % confidence interval: 0.005 - 0.9 %), 0.2 % (0.04 - 1.2 %), 0.7 % (0.3 - 1.9 %), 2.3 % (1 - 5.2 %) and 6.9 % (1.7 - 24.0 %), respectively. CONCLUSION: The age-dependent prevalences in this glaucoma screening program are in good agreement with the regression models of Tuck-Crick and Quigley-Vitale, especially in the age range of 40 - 80 years. The model for the 5-year incidences describes the tight relationship between age and 5-year risk for POAG. We estimate the number of new POAG cases in Austria in 2001-2006, 2010-2015, 2020-2025 and 2030-2035 at the age between 40 and 80 years to reach 49 100, 52 100, 62 000 and 69 600 patients, respectively.

[The Salzburg-Moorfields Collaborative Glaucoma Study: first results of the prevalence and 5-year incidences in this prospective, population-based longitudinal study]. / Die Salzburg-Moorfields-Collaborative-Glaucoma Study: Erste Ergebnisse der Prävalenzen und 5-Jahres-Inzidenzen in dieser prospektiven, bevölkerungsbasierten Longitudinalstudie.

BACKGROUND: This prospective, population-based longitudinal study describes prevalences and 5-year incidences of individuals with normal findings, ocular hypertension (OHT) and primary open-angle glaucoma (POAG) admitted to the Salzburg-Moorfields Collaborative Glaucoma Study (SMCGS). PATIENTS AND METHODS: The SMCGS is embedded in a government-supported glaucoma blindness prevention programme in Salzburg (Austria) which is designed for a minimum of 10-years follow-up. Each subject receives a complete ophthalmological examination. In total, the findings of 853 subjects with complete data sets were analysed and evaluated. RESULTS: The prevalence of participants with normal findings was 75 % (95 % CI: 72 - 78 %) at the initial examination, decreasing to 64 % (95 % CI: 60 - 67 %) at the 5-year follow-up. The prevalence of OHT at the initial exam of 2.3 % (95 % CI: 1.4 - 3.6 %) increased to 3.5 % (95 % CI: 2.4 - 5.0 %) at the 5-year follow-up exam with an incidence of 1.2 % (95 % CI: 0.6 - 2.2 %). Finally, the prevalence of POAG of 0.6 % (95 % CI: 0.2 - 1.4 %) increased to 1.6 % (0.9 - 2.7 %) at the 5-year exam which corresponds to a 5-year incidence of POAG of 1.0 % (0.5 - 2.0 %). CONCLUSION: The prevalence of POAG increases statistically significantly when compared at the initial and 5-year follow up exam (p = 0,002). Our results confirm the positive relation between age and the prevalence of POAG (odds ratio = 0.89, 95 % CI: 0.81 - 0.98). The prevalence and 5-year incidence rates in this glaucoma prevention study are similar to those of other population-based studies.

[Driving habits of patients with glaucoma]. / Fahrgewohnheiten von Patienten mit Glaukom.

BACKGROUND: Central visual field defects due to glaucoma are common, increasing with old age. Impaired visual processing, for instance caused by glaucoma, may play a role in the aetiology of car accidents involving older drivers which can result in personal injury. Mandatory eye exams with assessment of the visual field in elderly people holding a driving licence will become more and more important, especially in a continuously ageing and increasingly mobile population. MATERIALS AND METHODS: In this prospective study, 80 patients with overt glaucoma and 52 patients without glaucoma, all holders of a valid driving licence, were enrolled. For each patient, the best corrected visual acuity was recorded and an examination of the central visual field was performed with automatic perimetry. In addition, a detailed questionnaire about the current driving habits of the patient was requested. RESULTS: In summary, 29 patients (36 %; 95 % CI: 26 - 48 %) of 80 glaucoma patients were driving a motor vehicle with binocular congruent scotomata within the central 30 degrees visual field, which is not sufficient to meet current legal requirements in Austria. In addition, 3 out of 29 impaired patients had a visual acuity that was below the mandatory legal requirements. A total of 39 patients (49 %; 95 % CI: 37 - 60 %) of the glaucoma patients fulfilled legal requirements. Examination of these patients showed only monocular or binocular central visual field defects that were not congruent. However, 12 (15 %; 95 % CI: 8 - 25 %) patients were holders of a valid driving licence, but had stopped driving some time ago. Based on the prevalence of glaucoma and the number of driving licence holders, the projected number of actively driving glaucoma patients who do not meet the legal requirements regarding the visual field is probably around 15,400 (7,400 - 29,500) in Austria and around 163,500 (79,000 - 313,500) in Germany. CONCLUSIONS: Time limits for the validity of the driving licence within the European Community have been set. In addition, the legal requirements for driving a motor vehicle should also be clearly defined, especially the requirements regarding the visual field and the acceptable dimensions of central scotomata. In addition, a mandatory eye exam for older drivers to be performed by ophthalmologists should be considered in order to detect persons posing a safety risk in traffic.