Risk Factors of Age-Related Macular Degeneration in a Population-Based Study: Results from SHIP-TREND-1 (Study of Health in Pomerania-TREND-1).

BACKGROUND Age-related macular degeneration (AMD) is the most common cause of visual impairment in the elderly population in industrialized countries. The Study of Health in Pomerania (SHIP) with its cohort SHIP-TREND was designed to investigate risk factors and clinical disorders in the general population of northeast Germany. This work focused on the first follow-up of SHIP-TREND and determined associated modifiable risk factors of AMD. Modifying risk factors is important to slow the progression of early AMD as there is currently no treatment for the late stage of geographic atrophy. Understanding AMD-associated risk factors also plays an important role in the development of therapeutic concepts. MATERIAL AND METHODS Between 2016 and 2019, data were collected from a total of 2507 initially randomly selected subjects from the general population aged 28 to 89 years. Non-mydriatic fundus photography of the right eye was performed in 2489 subjects. Grading of AMD was performed using the Rotterdam classification system. RESULTS We included 1418 gradable fundus photographs in the analysis. The risk of AMD changes increased with age and was positively correlated with HDL cholesterol, fT3, and low educational level. In men, BMI and cigarette smoking were also positively associated with AMD changes. CONCLUSIONS This study emphasizes the consideration of various metabolic pathways for the development of therapeutic concepts.

Glaucoma Patients Have a Lower Abundance of Butyrate-Producing Taxa in the Gut.

Purpose: Glaucoma is an eye disease that is the most common cause of irreversible blindness worldwide. It has been suggested that gut microbiota can produce reactive oxygen species and pro-inflammatory cytokines that may travel from the gastric mucosa to distal sites, for example, the optic nerve head or trabecular meshwork. There is evidence for a gut-eye axis, as microbial dysbiosis has been associated with retinal diseases. We investigated the microbial composition in patients with glaucoma and healthy controls. Moreover, we analyzed the association of the gut microbiome with intraocular pressure (IOP; risk factor of glaucoma) and vertical cup-to-disc ratio (VCDR; quantifying glaucoma severity). Methods: The discovery analyses included participants of the Rotterdam Study and the Erasmus Glaucoma Cohort. A total of 225 patients with glaucoma and 1247 age- and sex-matched participants without glaucoma were included in our analyses. Stool samples were used to generate 16S rRNA gene profiles. We assessed associations with 233 genera and species. We used data from the TwinsUK and the Study of Health in Pomerania (SHIP) to replicate our findings. Results: Several butyrate-producing taxa (e.g. Butyrivibrio, Caproiciproducens, Clostridium sensu stricto 1, Coprococcus 1, Ruminococcaceae UCG 007, and Shuttleworthia) were less abundant in people with glaucoma compared to healthy controls. The same taxa were also associated with lower IOP and smaller VCDR. The replication analyses confirmed the findings from the discovery analyses. Conclusions: Large human studies exploring the link between the gut microbiome and glaucoma are lacking. Our results suggest that microbial dysbiosis plays a role in the pathophysiology of glaucoma.

Variability of biomarkers used for the classification of metabolic syndrome: A repeated measurements study.

BACKGROUND AND AIMS: The definition of the metabolic syndrome consists of five components. The underlying measurements are subject to intra-individual variability. This repeated measurements study investigated the impact of intra-individual measurement variability on the stability of the diagnosis of metabolic syndrome over 12 months. METHODS AND RESULTS: Twenty-five employees of the University Medicine Greifswald aged 22-70 years were examined once a month over one year. Examinations included blood sampling and anthropometric and blood pressure measurements. Laboratory measurements included glucose, cholesterol (high-density lipoprotein [HDL], and low-density lipoprotein [LDL]), and triglycerides. The metabolic syndrome was defined according to the International Diabetes Federation modified for non-fasting blood samples. Variations in continuous metabolic markers were assessed using coefficients of variation (CV) and intra-class correlation coefficients (ICC). Overall eight participants (32%) were categorized at least once within 12 months as having a metabolic syndrome; in none of those metabolic syndrome was found consistently over the study follow-ups. The Cohen's Kappa for metabolic syndrome was 0.57. CV was highest for triglycerides (27.5%) followed by glucose (10.1%), LDL- (9.5%), and HDL-cholesterol (8.6%). ICC's were lowest for glucose (0.51), triglycerides (0.65), systolic (0.68), and diastolic blood pressure (0.69). CONCLUSION: We showed that the measurement of biomarkers defining the metabolic syndrome is a time-varying condition with implications for the concept of the metabolic syndrome. To account for this uncertainty in prevalence studies we propose to identify uncertain cases according to the current definition of the metabolic syndrome. For analysing associations we recommend to apply probabilistic sensitivity analyses.

Modeling transcriptomic age using knowledge-primed artificial neural networks.

The development of 'age clocks', machine learning models predicting age from biological data, has been a major milestone in the search for reliable markers of biological age and has since become an invaluable tool in aging research. However, beyond their unquestionable utility, current clocks offer little insight into the molecular biological processes driving aging, and their inner workings often remain non-transparent. Here we propose a new type of age clock, one that couples predictivity with interpretability of the underlying biology, achieved through the incorporation of prior knowledge into the model design. The clock, an artificial neural network constructed according to well-described biological pathways, allows the prediction of age from gene expression data of skin tissue with high accuracy, while at the same time capturing and revealing aging states of the pathways driving the prediction. The model recapitulates known associations of aging gene knockdowns in simulation experiments and demonstrates its utility in deciphering the main pathways by which accelerated aging conditions such as Hutchinson-Gilford progeria syndrome, as well as pro-longevity interventions like caloric restriction, exert their effects.

Variability of Thyroid Measurements from Ultrasound and Laboratory in a Repeated Measurements Study.

BACKGROUND: Variability of measurements in medical research can be due to different sources. Quantification of measurement errors facilitates probabilistic sensitivity analyses in future research to minimize potential bias in epidemiological studies. We aimed to investigate the variation of thyroid-related outcomes derived from ultrasound (US) and laboratory analyses in a repeated measurements study. SUBJECTS AND METHODS: Twenty-five volunteers (13 females, 12 males) aged 22-70 years were examined once a month over 1 year. US measurements included thyroid volume, goiter, and thyroid nodules. Laboratory measurements included urinary iodine concentrations and serum levels of thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fT4), and thyroglobulin. Variations in continuous thyroid markers were assessed as coefficient of variation (CV) defined as mean of the individual CVs with bootstrapped confidence intervals and as intraclass correlation coefficients (ICCs). Variations in dichotomous thyroid markers were assessed by Cohen's kappa. RESULTS: CV was highest for urinary iodine concentrations (56.9%), followed by TSH (27.2%), thyroglobulin (18.2%), thyroid volume (10.5%), fT3 (8.1%), and fT4 (6.3%). The ICC was lowest for urinary iodine concentrations (0.42), followed by fT3 (0.55), TSH (0.64), fT4 (0.72), thyroid volume (0.87), and thyroglobulin (0.90). Cohen's kappa values for the presence of goiter or thyroid nodules were 0.64 and 0.70, respectively. CONCLUSION: Our study provides measures of variation for thyroid outcomes, which can be used for probabilistic sensitivity analyses of epidemiological data. The low intraindividual variation of serum thyroglobulin in comparison to urinary iodine concentrations emphasizes the potential of thyroglobulin as marker for the iodine status of populations.

Association between cardiorespiratory fitness and handgrip strength with age-related macular degeneration: a population-based study.

AIM: To assess whether cardiorespiratory fitness (CRF) and handgrip strength, two objective markers of physical fitness, are associated with age-related macular degeneration (AMD). METHODS: We analysed cross-sectional data from the population-based Study of Health in Pomerania (2008-2012) including 1173 adult men and women aged 20-79 years. Fundus photography of the central retina was recorded with a non-mydriatic camera, and images were graded according to an established clinical AMD classification scale by an experienced reader. CRF was measured using peak oxygen uptake (peakVO2), oxygen uptake at the anaerobic threshold (VO2@AT), and maximum power output (Wmax) from standardised cardiopulmonary exercise testing on a bicycle ergometer according to a modified Jones protocol. Handgrip strength was assessed using a handheld dynamometer. Adjusted prevalence ratios (PR) for the associations of peakVO2, VO2@AT, Wmax and handgrip strength with AMD were derived from multivariable Poisson regression models. RESULTS: PeakVO2, VO2@AT, Wmax and handgrip strength were not associated with AMD. Adjusted PR for AMD associated with a 1-SD increment in peakVO2, VO2@AT, Wmax and handgrip strength were 1.05 (95% CI 0.82 to 1.34), 0.96 (95% CI 0.78 to 1.18), 1.10 (95% CI 0.86 to 1.41) and 1.01 (95% CI 0.79 to 1.30), respectively. These associations were not modified by age, sex, smoking, body mass index and diabetes. Estimates in sensitivity analysis for confounding, selection bias and missing data were similar. CONCLUSION: In our study, CRF and handgrip strength were not associated with AMD. Nevertheless, longitudinal studies with bigger sample sizes are needed to furtherly examine these associations.

Age-Related Macular Degeneration and Associated Risk Factors in the Population-Based Study of Health in Pomerania (SHIP-Trend).

BACKGROUND Age-related macular degeneration (AMD) is the leading cause of visual impairment in developed countries, especially in the older population. The Study of Health in Pomerania (SHIP) is a population-based study designed to investigate risk factors and clinical disorders in the general population. In the present study, we analysed the AMD prevalence and risk factors in the north-eastern German population. MATERIAL AND METHODS From 2008 to 2012, we collected data among participants ages 29-79 years. The study population consisted of 4420 individuals. Non-mydriatic retinal photographs were taken of 3934 participants. AMD stages were graded according to the Rotterdam Classification System and the International Classification System. RESULTS Photographs from 1854 participants were available for grading. The baseline examinations showed small hard drusen (<63 µm, stage 0b and 0c) were present in 10.7% of the participants (stage 0b in 7.5% and stage 0c in 3.2%). Earliest signs of AMD were detected in 28.68% (stage 0b in 7.5% and stage 1b in 21.18%). Late AMD (geographic atrophy and neovascular AMD, stages 4a and 4b) were identified in 0.43% (stage 4a in 0.16% and stage 4b 0.27%). Risk of AMD increased significantly with age and higher body mass index, waist circumference, hip circumference, and weight-waist-ratio. Smoking, sex, systolic and diastolic blood pressure, HbA1c, cholesterol, HDL-cholesterol, LDL-cholesterol, and triglyceride were not associated with AMD in this study. CONCLUSIONS The prevalence of AMD increases with age and obesity-associated factors. These results must be verified in the follow-up. Data concerning the incidence of AMD will be available after the 5- and 10-year follow-ups.

Prevalence of impaired functional reading ability and its association with quality of life, daily activity, mobility and social participation among general older adults in Germany.

BACKGROUND: The prevalence of visual impairment and of impaired functional reading ability rapidly increase with age. However, functional reading ability is essential for an autonomous lifestyle. We analyzed the prevalence of impaired functional reading ability in the general elderly population and the association of impaired functional reading ability with quality of life, daily activities, mobility, and social participation. METHODS: Cross-sectional data from a population-based cohort were analyzed. Participants aged ≥65 years were tested for their functional reading ability using (1) Nieden charts (cognitive reading ability) and (2) a test in which a telephone number had to be found (reading comprehension). Prevalences of impaired functional reading ability were calculated. In multivariable regression models, the associations of cognitive reading ability (1) with quality of life, daily activities, mobility, and social participation were examined. RESULTS: 60 of 780 participants (7.69%) were able to read the third last text of the Nieden test (good cognitive reading ability), whereas 7 participants (0.9%) were unable to read any of the texts. 716 participants (91.8%) identified the phone book entry successfully (good reading comprehension). Multivariable regression models revealed no significant associations of the cognitive reading ability (1) with quality of life, daily activities, social participation, and mobility. CONCLUSION: Our results showed a high prevalence of impaired cognitive reading ability (1). Reading comprehension (2) was slightly affected. The loss of cognitive reading ability usually progresses over years; signs and symptoms might remain unrecognized when compensated by other functions.

Association of anthropometric markers with globe position: A population-based MRI study.

PURPOSE: Exophthalmometry is a common examination in ophthalmology. For example it is relevant for diagnosis or follow-up of thyroid eye disease. However, exophthalmometry is affected by several factors such as ethnicity, sex and age. The purpose of this study was to determine the globe position by magnetic resonance imaging (MRI) and to investigate its correlates among the general Northeast German adult population. METHODS: A total of 3030 subjects aged between 20 and 89 from the population-based Study of Health in Pomerania (SHIP) underwent a standardised whole-body MRI. Axial length and globe position were determined in axial T1-weighted images of the orbit. The image had to include the corneal apex as well as the optic nerve head. Study participants were excluded from imaging analysis if there was no plane available that included both structures. Further exclusion criterion was a lateral deviation of the subject's viewing direction. Images with inadequate quality due to motion artefacts or other technical reasons were excluded as well. Globe position was defined as the perpendicular distance between the interzygomatic line and the posterior surface of the cornea (exophthalmometric value). The distance between the posterior surface of the cornea and the posterior pole of the eyeball, at the boundary with orbital fat, was defined as axial length. We used posterior surface of the cornea for our measurements, because it seemed to be less vulnerable for motion artefacts than the anterior one. Moreover body measurements including body mass index (BMI), waist and hip circumferences were determined. Associations between anthropometric measurements with exophthalmometric outcomes were analysed by linear regressions adjusted for age and stratified by sex. P-values <0.05 were considered as statistically significant. To assess intra-reader variability intra-class correlation coefficients (ICC) were computed for repeated measurements of the MRI scans of 25 subjects. RESULTS: After considering the exclusion criteria 1926 evaluable subjects remained. There was no significant difference between means of right and left eyes. The mean exophthalmometric value was significantly higher in men (16.5 +/- 2.2 mm) than in women (15.3 +/- 2.1 mm). The mean MRI-axial length was 23.4 +/- 0.8 mm for men and 22.8 +/- 0.9 mm for women. BMI, waist and hip circumferences were positively correlated with exophthalmometric value (p<0.001). Difference of mean MRI-based exophthalmometric value for obese subjects (BMI ≥30 kg/m2) and non-overweight (BMI <25 kg/m2) was 2.1 mm for men and 1.6 mm for women. ICC between 0.97 and 0.99 indicate excellent repeatability of our method. CONCLUSION: We conclude that MRI-based exophthalmometric values are positively correlated with BMI, waist- and hip-circumference among the general Northeast German adult population. This association is independent from age and axial length. Consequently bodyweight of patients should be regarded to interpret exophthalmometric values correctly. MRI-exophthalmometry seems to be a suitable method to determine globe position. Considering the large number of study participants, exophthalmometric values of our study could be used as comparative values for exophthalmometry of people of Western European descent in future.

[Static Retinal Vessel Analysis in Population-based Study SHIP-Trend]. / Statische Gefäßanalyse der retinalen Blutgefäße in einer populationsbasierten Kohorte unter Berücksichtigung des Diabetes mellitus.

BACKGROUND: Interdisciplinary investigations of possible connections between general diseases and ophthalmological changes are difficult to perform in the clinical environment. But they are gaining in importance as a result of the age-related increase in chronic diseases. The collection of health-related parameters in the Study of Health in Pomerania (SHIP) project allows to derive conclusions for the general population. METHODS: The population-based SHIP trend study was conducted between 2008 and 2012 in Greifswald. The baseline cohort included 4420 subjects (response 50.1%) at the age of 20 to 84 years. The pre-existence of arterial hypertension, diabetes mellitus and smoking status were questioned in a standardized questionnaire, the blood pressure and the HbA1c were determined by the laboratory. The vascular diameter of retinal arterioles and venules were determined by means of non-mydriatic fundus images and the retinal arterial (CRAE) and venous equivalent (CRVE) were calculated therefrom. The association of diabetes mellitus, HbA1c, smoking status and blood pressure with the retinal vascular parameters was tested for age and sex with linear regression models. RESULTS: In 3218 subjects with evaluable standardized fundus photographs, significant associations of elevated HbA1c (> 6.5%), smoking status and systolic and diastolic blood pressure were found with the retinal vessel widths CRAE and CRVE. Anamnestic diabetes mellitus, on the other hand, was not associated with any of the vascular parameters. CONCLUSION: This research study reveals a relevant correlation between general diseases and the retinal blood flow in the eye. Therefore, general diseases can induce ophthalmological changes and eye examination can provide information for the assessment of general diseases.

Cross-sectional association between oral health and retinal microcirculation.

AIM: To investigate the relation between oral health status and microcirculation, we analysed the association between periodontitis and number of teeth with retinal vessel diameters in a population-based study. METHODS: We analysed data from the Study of Health in Pomerania-TREND (SHIP-TREND). All subjects (3,183 for number of teeth, 3,013 for mean probing depth and 2,894 for mean attachment level) underwent nonmydriatic funduscopy and dental examination. We measured central retinal arteriolar (CRAE), venular (CRVE) vessel diameters and calculated arterio-venous ratio (AVR) from static vessel analysis (SVA). Periodontal status was assessed using the case definition of the Center for Disease Control and Prevention/American Academy of Periodontology (CDC/AAP). Data were analysed by linear (CRAE, CRVE, AVR) and logistic regression (AVR < 0.8) adjusted for age, sex, smoking status, alcohol consumption, body mass index, systolic blood pressure, hsCRP and type-2-diabetes mellitus. RESULTS: Only in men, significant associations were found between periodontal and retinal conditions. Severe periodontitis [ß = -0.0120 (-0.0218; -0.0007 95%-CI)] and mean probing depth [ß = -0.0054 (-0.0105; -0.0002 95%-CI)] were inversely associated with AVR; severe periodontitis [ß = 3.80 (0.61; 6.98 95%-CI)], mean probing depth [ß = 1.86 (0.23; 3.49 95%-CI)] and mean attachment level [ß = 1.31 (0.34; 2.27 95%-CI)] with CRVE and mean attachment level with CRAE [ß = 0.91 (0.14; 1.69 95%-CI)]. CONCLUSIONS: Our results point towards an association between periodontal conditions and AVR in men. Periodontitis may impact microvascular endothelium function. Improving oral health to reduce periodontitis might lead to reduced risk for other age-related diseases.

Evaluation of a visual acuity test using closed Landolt-Cs to determine malingering.

PURPOSE: To evaluate a visual acuity test (VAT) with unexpected optotypes to detect malingering. METHODS: We tested two groups. Group 1 consisted of 20 individuals with normal best corrected visual acuity (BCVA). Group 2 included participants with ocular diseases and reduced BCVA. All subjects underwent a VAT proposed by Gräf and Roesen to assess suspected malingering. This test used 36 charts with one Landolt-C per page. The first 20 optotypes were Landolt-Cs, while at positions 21, 26, 30, and 34 closed rings were presented. The testing distance was adapted to 50% of the test person's visual acuity. The test person was requested to name the gap direction of the Landolt-C within 3 s. The complete testing conversation was recorded digitally to determine response latency for each optotype from the audio tracks. RESULTS: The average response time was 0.46 s in group 1 and 0.45 s in group 2 for the first 20 Landolt-Cs. In both groups the response time was significantly extended (p < 0.05) for the first closed ring compared to the mean of the first 20 Landolt-Cs, (group 1: 2.9 s; group 2: 2.3 s). The following three closed rings had also longer response times. However, these differences were not significant. CONCLUSIONS: Our results suggest that the proposed test may be helpful to evaluate ocular malingering. The testing procedure appeared to be feasible and showed good repeatability. The fast training effect may be a limitation for malingering detection.

Thyroid function: a new road to understanding age-related macular degeneration?

Age-related macular degeneration (AMD) continues to be amongst the leading causes of blindness and visual impairment worldwide. AMD remains a degenerative disorder of unknown etiology with rising prevalence. It induces retinal changes and damages those parts of the retina which are essential for central vision. The risk of developing this condition is associated with increasing age. Early stages usually progress without warning signs over years. The major identified risk factors for AMD development are age, ethnicity, family history, and current smoking. Associations of other modifiable risk factors with AMD have been widely published but these studies have reported conflicting results and showed a lack of consistency. According to recent data published in BMC Medicine from the population-based Rotterdam study, thyroid hormones may contribute to a better characterization of AMD in clinical practice. In that study serum free thyroxine levels were positively associated with development of AMD. More studies are needed to validate these findings and to understand better the role of thyroid hormones in the pathogenesis of AMD disease. Please see related article: http://dx.doi.org/10.1186/s12916-015-0329-0.

Comparison of two non-mydriatic fundus cameras to obtain retinal arterio-venous ratio.

PURPOSE: To analyze device-dependent variability of two non-mydriatic fundus cameras to obtain arterio-venous ratio (AVR), central retinal arteriolar equivalent (CRAE), and central retinal venular equivalent (CRVE) in static vessel analysis (SVA). METHODS: We examined 53 participants (29 men, 24 women; median age 46 years) of the Study of Health in Pomerania (SHIP). We took 45° optic-disc-centered fundus images of the right eye with two different non-mydriatic fundus cameras. The first photograph was obtained from the TRC-NW 200, the second from the OCT 2000 (both Topcon Corporation, Tokyo, Japan). One experienced grader graded image quality from 1 "ideal quality" to 5 "not analyzable" and determined AVR, CRAE, and CRVE with the software Vesselmap3 (Imedos, Jena, Germany). RESULTS: Average image quality was 1.8 for the TRC-NW 200 and 1.6 for the OCT 2000. AVR could not be determined in 5 images of the TRC-NW 200 due to low image quality, while six images of the OCT 2000 were not analyzable. The difference between AVR taken from two different non-mydriatic cameras was 0.01 ± 0.03 in Bland-Altman plots. The difference between CRAE was 0.17 ± 10.15 and between CRVE was -2.32 ± 11.76. CONCLUSIONS: The two different non-mydriatic cameras showed good agreement with respect to image quality. When using the same reading software, AVR, CRAE, and CRVE agreed well. Thus, funduscopy and SVA seem to be robust against inter-device variability. As a result, device dependency can remain unconsidered in follow-up examinations with different technical equipment. However, variability might impact more with devices from different manufacturers.

High serum thyrotropin levels are associated with retinal arteriolar narrowing in the general population.

BACKGROUND: Recent studies have shown associations of hypothyroidism with arterial blood pressure, atherosclerosis, and inflammation. Based on these pathways, there might also be an association between hypothyroidism and retinal arteriolar narrowing (RAN), a marker of microvascular damage from hypertension, atherosclerosis, and inflammation. Against this background, the aim of this study was to investigate the putative association between serum thyrotropin (TSH) levels and RAN defined by arterio-venous ratio (AVR) from static vessel analysis. METHODS: We used data from 3189 individuals from the second population-based cohort of the Study of Health in Pomerania (SHIP-TREND-0). Thyroid function was defined according to serum TSH and serum diiodothyronine (3,5-T2) levels. Low and high serum TSH levels were defined by the cutoffs 0.3 mIU/L and 3.0 mIU/L. Fundus photography of the central retina was recorded with a nonmydriatic camera, and images were evaluated by one experienced reader. An AVR <0.8 was defined as decreased. Serum TSH levels, low and high TSH, and serum 3,5-T2 levels were associated with AVR by linear regression and with AVR <0.8 by Poisson regression, both adjusted for age, sex, cigarette smoking, alcohol consumption, and intake of beta-blockers. RESULTS: Serum TSH levels were significantly associated with AVR (ß=-0.028 [CI -0.049 to -0.007]; p=0.009) and with a decreased AVR <0.8 (relative risk=2.05 [CI 1.13-3.73]; p=0.019). Individuals with high TSH had a 1.43 higher risk for a decreased AVR ([CI 1.04-1.96]; p=0.027) than individuals with serum TSH levels within the reference range. Serum 3,5-T2 levels were also associated with a decreased AVR (relative risk for an increase of 1 nM=0.45 [CI 0.23-0.87]; p=0.017). CONCLUSIONS: Our results substantiate evidence for an association between hypothyroidism and RAN. Potential mechanisms explaining this association are long-term hypertension, atherosclerotic processes, and inflammation.

Relationship of systemic blood pressure with ocular perfusion pressure and intraocular pressure of glaucoma patients in telemedical home monitoring.

BACKGROUND: We evaluated the relation of systemic blood pressure with intraday variations in ocular perfusion pressure and intraocular pressure in patients with primary open-angle glaucoma in a telemedical home monitoring scenario. MATERIAL/METHODS: In the project Teletonometry Mecklenburg-Vorpommern (TTMV) patients were equipped with a home monitoring system for 24-hour self-measurements of intraocular pressure and blood pressure for a period of six months. All measurements were transmitted via telephone modem to an electronic patient record. Ocular perfusion pressure (OPP) was automatically calculated from self-measurements of intraocular pressure (IOP), systolic (SBP) and diastolic blood pressure (DBP) using the equation: OPP=[2/3*(2/3*DBP+1/3*SBP)]-IOP. We present the temporal characteristics of 70 patients with primary open-angle glaucoma based on 3282 self-measurements. RESULTS: The diurnal ocular perfusion pressure trend showed four characteristic phases (7am - 12am, 12am - 6pm, 6pm - 10pm, and 10pm - 7am). Between 7am and 12am ocular perfusion pressure and simultaneously systolic and diastolic blood pressure were significantly depressed compared to all other phases (p<0.05) whereas intraocular pressure showed no significant shifting. Instead intraocular pressure was significantly depressed between 6pm and 10pm (p<0.05) where ocular perfusion pressure reached the highest intraday values. CONCLUSIONS: We found that ocular perfusion pressure in patients with primary open-angle glaucoma showed remarkable circadian fluctuations. A significant decrease in the morning was associated with significantly depressed systolic and diastolic blood pressure levels. In addition we observed normal intraocular pressure values in the morning but a significant decrease in the evening which did not affect ocular perfusion pressure. These conclusions strengthen the evidence that systemic blood pressure fundamentally influences ocular circulation and consequently glaucoma progression.

Distribution of mean, systolic and diastolic ocular perfusion pressure in telemedical homemonitoring of glaucoma patients.

BACKGROUND: To analyze the relation and distribution of mean, systolic and diastolic ocular perfusion pressure (OPP) in telemedical homemonitoring of patients with primary open-angle glaucoma (POAG). METHODS: 70 patients with POAG measured intraocular pressure (IOP) and blood pressure at home for a period of 6 months with the Goldmann applanation self-tonometer Ocuton S and the blood pressure device boso medicus PC. Twenty-four-hour profiles were taken every 4 weeks in addition to single measurements in the morning and evening once a week. All measured values were transmitted to an electronic patient record, which calculated OPP by taking systolic, diastolic and mean arterial blood pressure and subtracting IOP. RESULTS: We analyzed 3,282 values of mean, systolic and diastolic OPP. The quantity of values below the risk levels of the Barbados Eye Studies was calculated. We found values lower than the risk levels for LE: 49 (1.5%)/RE: 60 (1.8%) systolic OPP, LE: 1,623 (49.5%)/RE: 1,761 (53.7%) diastolic OPP and LE: 687 (20.9%)/RE: 794 (24.2%) mean OPP. The individual average OPP levels of all 70 patients below the risk levels showed the following distribution: LE: 4 (5.7%)/RE: 6 (8.6%) systolic OPP, LE: 19 (27.1%)/RE: 20 (28.6%) diastolic OPP and LE: 10 (14.3%)/RE: 10 (14.3%) mean OPP. CONCLUSION: The individual distribution of different OPP values in POAG patients is not easy to interpret for clinical ophthalmologists. Precise practicable guidelines for clinical use still have to be determined.

Effect of different artificial tears against desiccation in cultured human epithelial cells.

BACKGROUND: A large number of artificial tears is widely used to treat dry eye symptoms. To test the efficacy of these drugs independent of individual parameters in vitro models are required. As described previously, we employed a reproducible in vitro cell culture system to evaluate the desiccation protection capability of some artificial tears. In THE PRESENT PAPER DATA IS PRESENTED OF ANOTHER SET OF PHARMACEUTICAL AGENTS. MATERIAL/METHODS: Conjunctival epithelial cell line Chang 1-5c-4 (series 1) and the corneal cell line 2.040 pRSV-T (series 2) were cultured under standard conditions. Confluent cells were wetted for 20 min with artificial tears (Arufil Uno, Arufil, Lacrimal, Lacophthal sine, Siccaprotect, Tears Again, Vidisept EDO, Vistil, Wet Comod) or PBS as a control. After exposure to a constant air flow for 0, 15, 30 and 45 minutes respectively, cells were incubated with the vital dye alamarBlue. Subsequently, absorption of the oxidised form of the dye was assessed using an ELISA-Reader. RESULTS: Cell best survival rates in series 1 after 15 min were found for Lacrimal (0.89), Wet Comod (0.84) compared to PBS (0.66) and in series 2 for Vidisept EDO (0.57) and Lacrimal (0.56) compared to PBS (0.01). After 45 min highest survival was seen in series 1 for Lacrimal (0.46) and Lacophthal sine (0.36) compared to PBS (0.33) and in series 2 for Lacrimal (-0.06) and Arufil (-0.16) compared to PBS (-0.23). CONCLUSIONS: Both cell lines tested showed different susceptibility towards desiccation and the artificial tears showed differences in preventing cells from desiccation.