Pseudoexfoliation syndrome and asymptomatic myocardial dysfunction

Pseudoexfoliation syndrome: Are the eyes the mirror of the heart?

INTRODUCTION

Pseudoexfoliation syndrome (PEX) is a disease characterized by the accumulation of fibrillary material in the extracellular matrix in the eye and many tissues. Myocardial involvement occurs as in other storage diseases. Speckle tracking echocardiography is a quantitative echocardiography modality that enables the detection of subclinical changes that cannot be detected by standard echocardiographic evaluation. In this study, we aimed to evaluate potential subclinical myocardial dysfunction in PEX patients by speckle tracking echocardiography.

METHODS AND RESULTS

The study group consisting of 29 cardiac asymptomatic pseudoexfoliation syndromes and 30 healthy volunteers were included in this case-control cross-sectional study. Detailed echocardiographic evaluations and strain analyses of all participants were performed. Concerning standard echocardiographic parameters, there was only a marginally significant difference between the two groups in the e' mean wave, and it was lower in the PEX group than the control group (0.07 ± 0.03, 0.10 ± 0.08, respectively, P = .06). However, in strain echocardiography, the global longitudinal strain (GLS) value was observed to be significantly lower in the PEX group than the control group (-17.02 ± 2.02, -19.29 ± 2.26, respectively P < .001). GLS was observed to be an independent predictor in the multivariable logistic regression model made to determine independent predictors of PEX syndrome (OR = 0.59, CI = 0.418-0.832, P = .003).

CONCLUSION

Subclinical myocardial involvement in PEX syndrome, in which standard echocardiographic techniques are blinded, can be detected by the strain echocardiography. PEX causes deterioration in the deformation parameters of the left ventricle. Systemic involvement should not be forgotten in patients with PEX and cardiac functions should be monitored.

Exfoliation Syndrome: A Disease of Autophagy and LOXL1 Proteopathy

Exfoliation syndrome (XFS) is an age-related disease involving the deposition of aggregated fibrillar material (exfoliation material) at extracellular matrices in tissues that synthesize elastic fibers. Its main morbidity is in the eye, where exfoliation material accumulations form on the surface of the ciliary body, iris, and lens. Exfoliation glaucoma (XFG) occurs in a high proportion of persons with XFS and can be a rapidly progressing disease. Worldwide, XFG accounts for about 25% of open-angle glaucoma cases. XFS and XFG show a sharp age-dependence, similarly to the many age-related diseases classified as aggregopathies. Progress in understanding the cellular bases for XFS/XFG has been slowed by a lack of experimental models. Working with primary human tenon fibroblasts (TF) derived from trabeculectomies of XFG patients and age-matched primary open-glaucoma controls, we found that TF from XFG cells display many of the functional features observed in cells from other protein aggregate diseases, such as Parkinson, Alzheimer, Huntington, and age-related macular degeneration. We have documented defects in lysosomal positioning, microtubule organization, autophagy processing rate, and mitochondrial health. In regard to failure of lysosomal and autophagosome positioning in XFG cells, we have found that XFG TF are unable to establish the transnuclear microtubule organizing center that is required for efficient centripetal vesicular locomotion along microtubules. In regard to potential sources of the autophagy malfunction, we have directed our attention to a potential role of the lysyl oxidase-like 1 protein (LOXL1), the elastic fiber catalyst that displays variant-dependent association with risk for XFG. Our experiments show that (a) in XFG cells, a substantial fraction of LOXL1 is processed for degradation by the autophagic system; (b) most of the LOXL1 N-terminus domain exists in a highly disordered state, a condition known to greatly increase the frequency of polypeptide misfolding; (c) that maximum misfolding occurs at amino acid position 153, the location of the high risk variant G153D; and (d) that replacement of glycine (G) by aspartate (D) there results in a substantial decrease in disorder within the 20 amino acid surrounding domain. Finally, we show that clusterin, a protein that can be induced by the presence of intracellular, or extracellular aggregates, is uniformly overexpressed in XFG TF. The implications of our results for a theory relating XFG to cellular aggregopathy are discussed.

[Pseudoexfoliation syndrome and pseudoexfoliation glaucoma]

Pseudoexfoliation syndrome is an age-related systemic disease that mainly affects the anterior structures of the eye. Despite a worldwide distribution, reported incidence and prevalence of this syndrome vary widely between ethnicities and geographical areas. The exfoliative material is composed mainly of abnormal cross-linked fibrils that accumulate progressively in some organs such as the heart, blood vessels, lungs or meninges, and particularly in the anterior structures of the eye. The exact pathophysiological process still remains unclear but the association of genetic and environmental factors are thought to play a role in the development and progressive extracellular accumulation of exfoliative material. Hence, LOXL1 gene polymorphisms, responsible for metabolism of some components of elastic fibers and extracellular matrix, and increased natural exposure to ambient ultraviolet or caffeine consumption have been associated with pseudoexfoliation syndrome. Ophthalmological manifestations are commonly bilateral with an asymmetric presentation and can lead to severe visual impairment and blindness more frequently than in the general population, mainly related to glaucoma and cataract. Pseudoexfoliation glaucoma is a major complication of pseudoexfoliation syndrome and represents the main cause of identifiable glaucoma worldwide. Visual field progression is more rapid than that observed in primary open angle glaucoma, and filtering surgery is more frequently required. Nuclear cataract is more frequent and occurs earlier than in the general population. Owing to poorer pupil dilation and increased zonular instability, cataract surgery with pseudoexfoliation is associated with a 5- to 10-fold increase in surgical complications compared to cataract surgery without pseudoexfoliation. Some specific treatments targeting production, formation or accumulation of exfoliative material could improve the prognosis of this syndrome.

Chosen Vascular Risk Markers in Pseudoexfoliation Syndrome: An Age-Related Disorder

Purpose

To evaluate lipids and C-reactive protein serum levels in patients with pseudoexfoliation syndrome (PEX) in the Polish population.

Methods

96 patients were studied with PEX and 79 control subjects. Total cholesterol, triglycerides, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, non-HDL-cholesterol and CRP serum levels, and TG/HDL-C and TC/HDL-C indexes were assessed.

Results

There were no significant differences in concentration of lipids and values of TC/HDL-C, TG/HDL-C, and non-HDL-C between PEX and control groups. High-sensitivity C-reactive protein was not increased in patients with PEX.

Conclusions

Our results cast doubt on the opinion on the possible PEX and vascular diseases relation. Further studies on this subject are mandatory.

Pseudoexfoliation syndrome and meibomian gland dysfunction

Pseudoexfoliation syndrome (PEX) is a relatively widespread generalized age-related disease of connective tissue. The condition of meibomians gland in patients with PEX not evaluated yet. Purpose. To evaluate the condition of meibomians glands in PEX. Methods. 132 eyes of 66 patients with PEX syndrome and 128 eyes of 64 patients without it were enrolled in the prospective study. Results. Signs of atonic changes of meibomians glands were similar in both groups. Meibomians gland dysfunction was significantly more expressed in patients with PEX (p < 0,05).

Pseudoexfoliation syndrome and ocular adnexa

Pseudoexfoliation syndrome (PEX) is a relatively widespread generalized age-related disease of connective tissue. It seems reasonable to evaluate the condition of ocular adnexa in patients with PEX. Purpose. To evaluate the condition of ocular adnexal tissue in PEX. Methods. 132 eyes of 66 patients with PEX syndrome and 128 eyes of 64 patients without it were enrolled in the prospective study. We evaluated function of upper eyelid levator muscle, lower eyelid retractors, horizontal lid laxity (HLL), canthal integrity, degree of retractors disinsertion and tone of orbicularis muscle. Results. HLL, degree of retractors disinsertion, laxity of medial canthal tendon were statistically significantly more expressed in patients with PEX (p < 0,05). The tone of orbicularis muscle and function of lower eyelid retractors were statistically lower in patients with PEX (p < 0,05). The function of eyelids levator muscle, tone of lateral canthal tendon and degree of ptosis were similar in both groups. Conclusion. Signs of atonic changes of ocular adnexa are relatively more common in patients with PEX (p < 0,05).

Autophagy and Mitochondrial Dysfunction in Tenon Fibroblasts from Exfoliation Glaucoma Patients

Purpose

To test the hypothesis that autophagy dysfunction is involved in exfoliation syndrome (XFS), a systemic disorder of extracellular elastic matrices that causes a distinct form of human glaucoma.

Methods

Fibroblasts derived from tenon tissue discards (TFs) from filtration surgery to relieve intraocular pressure in XFS patients were compared against age-matched TFs derived from surgery in primary open-angle glaucoma (POAG) patients or from strabismus surgery. Differential interference contrast light, and electron microscopy were used to examine structural cell features. Immunocytochemistry was used to visualize LOXL1 and Fibulin-5, lysosomes, endosomes, Golgi, and microtubules. Light scatter, Cyto-ID^TM and JC1 flow cytometry were used to measure relative cell size, autophagic flux rate and mitochondrial membrane potential (MMPT), respectively. Enhanced autophagy was induced by serum withdrawal.

Results

In culture, XFS-TFs were 1.38-fold larger (by light scatter ratio, p = 0.05), proliferated 42% slower (p = 0.026), and were morphologically distinct in 2D and 3D culture compared to their POAG counterparts. In extended 3D cultures, XFS-TFs accumulated 8–10 times more Fibulin-5 than the POAG-TFs, and upon serum withdrawal, there were marked deficiencies in relocation of endosomes and lysosomes to the perinuclear area. Correspondingly, the XFS-TFs displayed significant accumulation of the autophagasome marker LC3 II (3.9 fold increase compared to POAG levels, p = 0.0001) and autophagic flux rate as measured by Cyto-ID dye was 53% lower in XFS-TFs than in POAG-TFs (p = 0.01), indicating reduced clearance of autophagasomes. Finally the percent of cells with diminished MMPT was 3–8 times larger in the XFS-TFs than in POAG-TFs (p = 0.02).

Conclusions

Our results provide for the first time a link between XFS pathology to autophagy dysfunction, a major contributor to multiple age related diseases systemically throughout the body, in the brain and in the retina. A diminished capacity for degradation of denatured protein and aging cellular organelles may underpin the development of extracellular protein aggregates in XFS.

Prevalence of Pseudoexfoliation Syndrome in Turkish Patients with Senile Cataract

PURPOSE

To investigate the prevalence of pseudoexfoliation syndrome (PEX) among Turkish patients with senile cataract.

MATERIALS AND METHODS

Records of 352 eyes of 352 patients who underwent cataract surgery were analyzed in this retrospective study. The presence of PEX, type of cataract, intraocular pressure (IOP), glaucoma, age-related macular degeneration, and systemic diseases (coronary artery disease, hypertension, diabetes mellitus) were recorded.

RESULTS

The overall prevalence of PEX syndrome was detected to be 11%. The mean age of PEX patients was significantly higher than without PEX (74.4 ± 7.2 years and 69.3 ± 11.4 years, respectively, p = 0.004). The most common cataract type in the PEX patients was mixed-type cataract determined in 51.2% of patients. IOP was significantly higher in eyes with PEX than in eyes without it (16.1 ± 4.5 mmHg and 14.7 ± 3.8 mmHg, respectively; p = 0.03). Moreover, the prevalence of age-related macular degeneration was found to be significantly higher, and prevalence of glaucoma slightly higher in PEX patients than without PEX.

CONCLUSION

Pseudoexfoliation syndrome is a common condition in Turkish people. PEX is associated with mixed type of cataract, age-related macular degeneration, and elevated IOP. Therefore, PEX patients should be checked for concomitant diseases.

Systemic Associations of Exfoliation Syndrome

Exfoliation syndrome (XFS) is an age-related disease characterized by the production, deposition, and progressive accumulation of a white, fibrillar, extracellular material in many ocular tissues, most prominent on the anterior lens surface and pupillary border. Its prevalence increases steadily with age in all populations. It is the most common identifiable cause of open-angle glaucoma worldwide and is a potentially reversible or even curable disease. First described in Finland in 1917 by Lindberg, it has long been associated with open-angle glaucoma. However, in recent years, it is being increasingly reported in conjunction with a multiplicity of both ocular and systemic disorders, and the number of these is expected to grow, particularly with investigations based on attempts to associate other diseases with those genes known to be associated with XFS. Despite the focus on XFS as a cause of open-angle glaucoma for nearly a century, in reality it is still only an ocular manifestation of a protean systemic disease. It is a unique disorder with extensive and often serious ocular and systemic manifestations and not, as it has long been termed, a "form" or "type" of glaucoma. This misconception has delayed research into the molecular and cellular processes involved in its development, and the underestimation of its overall importance and its underlying causative mechanisms have largely been long ignored. The purpose of this article is to review the systemic disorders which are becoming increasingly associated with XFS. Reviews of epidemiology, genetics, biomarkers, molecular mechanisms of development, and ocular findings may be found elsewhere.

Plateletcrit in Ocular Pseudoexfoliation Syndrome

PURPOSE

The aim of this study was to compare all platelet markers, especially plateletcrit (PCT, total platelet mass), in patients with and without ocular pseudoexfoliation (PEX) syndrome.

METHODS

One hundred six patients with ocular PEX syndrome (study group) and 106 individuals without ocular PEX syndrome (control group) were enrolled in this retrospective case-control study. The biochemical/hematological laboratory results of both the study and control groups were analyzed by a clinician blinded to the group assignments. The main outcome measures were the PCT, platelet count (PLT), mean platelet volume (MPV), and platelet distribution width (PDW).

RESULTS

The mean PCT in the study and control groups were 0.206%±0.520% and 0.171%±0.410%, respectively (P<0.001), and the mean PDW in the study and control groups were 16.12%±1.21% and 14.68%±1.40%, respectively (P<0.001). There were no differences in the MPV or mean PLT (P=0.138 and P=0.055, respectively). The PCT cutoff value was 0.180 (area under the receiver operating characteristics curve, 0.706; P<0.001; 65% sensitivity; 74% specificity).

CONCLUSIONS

The PCT and PDW were significantly higher in patients with than without ocular PEX syndrome. These increased parameters may cause microvascular blood flow resistance and the heightened inflammatory response caused by excessive platelet activity, as with other cardiovascular diseases, and may also decrease aqueous humor outflow in ocular PEX syndrome.

Lack of association of LOXL1 gene variants in Japanese patients with central retinal vein occlusion without clinically detectable pseudoexfoliation material deposits

PURPOSE

A possible association has been reported between exfoliation syndrome (EX) and various ocular and systemic vascular disorders; however, it is unclear if there is an association between EX and central retinal vein occlusion (CRVO). Because latent deposits of exfoliation materials might not be recognized during slit-lamp examination, an ocular biopsy is required to establish a precise diagnosis. We evaluated a possible association between EX and CRVO using lysyl oxidase-like 1 (LOXL1) gene variants as alternative markers for EX.

METHODS

The allelic and genotypic frequencies of three LOXL1 variants (rs1048661, rs3825942, and rs2165241) were determined in 68 consecutive Japanese patients with CRVO [15 with exfoliation syndrome (EX+) and 53 without exfoliation syndrome (EX-)] and 90 control patients with cataract without EX (CT).

RESULTS

The frequencies of the rs1048661 and rs3825942 variants showed borderline difference between the CRVO and CT groups (p = 0.04085 and p = 0.06088, respectively, for allelic frequencies, and p = 0.06838 and p = 0.03482, respectively, for genotypic frequencies). Compared with the CT group, subgroup analysis showed that the CRVO EX+ group had significant differences in the allelic and genotypic frequencies of rs1048661 (p = 0.0006447 and p = 0.0001392, respectively) and had borderline differences in the allelic and genotypic frequencies of rs3825942 (p = 0.03403 and p = 0.07341, respectively), while the CRVO EX- group did not (p = 0.1324-0.6306). Subgroup analysis showed that the frequencies of rs2165241 did not differ between the CRVO and CT groups.

CONCLUSIONS

When the LOXL1 variants were used as disease markers for clinically undetectable EX, there was no association between CRVO and EX. The results suggested that the LOXL1 variants, which are well-established markers for EX, are not likely genetic markers for CRVO in Japanese subjects.

Pseudoexfoliation syndrome and cardiovascular diseases

Pseudoexfoliation (PEX) syndrome is a well-recognized late-onset disease caused by a generalized fibrillopathy. It is linked to a broad spectrum of ocular complications including glaucoma and perioperative problems during cataract surgery. Apart from the long-known intraocular manifestations, PEX deposits have been found in a variety of extraocular locations and they appear to represent a systemic process associated with increased cardiovascular and cerebrovascular morbidity. However, as published results are inconsistent, the clinical significance of the extraocular PEX deposits remains controversial. Identification of PEX deposits in the heart and the vessel wall, epidemiologic studies, as well as, similarities in pathogenetic mechanisms have led to the hypothesis of a possible relation between fibrillar material and cardiovascular disease. Recent studies suggest that PEX syndrome is frequently linked to impaired heart and blood vessels function. Systemic and ocular blood flow changes, altered parasympathetic vascular control and baroreflex sensitivity, increased vascular resistance and decreased blood flow velocity, arterial endothelial dysfunction, high levels of plasma homocysteine and arterial hypertension have all been demonstrated in PEX subjects. Common features in the pathogenesis of both atherosclerosis and PEX, like oxidative stress and inflammation and a possible higher frequency of abdominal aorta aneurysm in PEX patients, could imply that these grey-white deposits and cardiovascular disorders are related or reflect different manifestations of the same process.

The frequency of exfoliation syndrome in the central anatolia region of Turkey

Aim. The aim of this study was to investigate the frequency of exfoliation syndrome in the Central Anatolia region of Turkey and to evaluate its relationship with cardiovascular and ocular diseases. Methods. Patients over the age of 45 years who presented to the clinic were included in the study. All cases underwent a comprehensive ophthalmology examination. Exfoliation syndrome was diagnosed with the presence of exfoliative material on the lens anterior capsule or iris on slit lamp examination. The patients were divided into two groups as the exfoliation syndrome group and nonexfoliation syndrome group according to the presence of exfoliative material. Results. Exfoliative material was found in one or both eyes of 212 of the 2103 patients (10.1%) evaluated within the scope of the study. A significant relationship was found between exfoliation syndrome and increasing age and male gender. A significant relationship was found between exfoliation syndrome and glaucoma, cataracts, age-related macular degeneration, and phacodonesis. While no relationship was found between exfoliation syndrome and hypertension or diabetes mellitus, a significant relationship was found with coronary artery disease. Conclusion. The unilateral or bilateral exfoliation syndrome frequency was 10.1% in this hospital-based study. A statistically significant relationship was found between exfoliation syndrome and advancing age, gender, and coronary artery disease.

Mortality in Primary Open-Angle Glaucoma and Exfoliative Glaucoma

Purpose

To study mortality among unselected Finnish patients with either primary open-angle glaucoma (POAG) or exfoliative glaucoma (EG) after a minimum follow-up of 7 years after enrollment.

Methods

A total of 344 patients with POAG and 155 patients with EG had received free medication for the treatment of glaucoma from the Finnish National Social Insurance Institution (FSII). The FSII operates national health insurance, which is compulsory for all Finnish citizens. To be granted free medication, the patient has to file an application with a certificate from an ophthalmologist. If the predefined criteria for glaucoma specified by the Finnish Parliament are met, full reimbursement for glaucoma medications is granted and the patient is listed in the registry of FSII. We reviewed the records of 519 consecutive patients who had been diagnosed with glaucoma and to whom free medication had been granted between June 2004 and December 2005. Patients with acute glaucoma or secondary glaucoma were excluded. Those with open angles were classified into POAG or EG. The quality of the ophthalmologists’ records was high. The Finnish Population Registry, a governmental institute, provided information on those patients who had died before January 2013.

Results

At enrollment, the groups with POAG and EG were comparable as regards sex: 66% female with POAG and 68% with EG. The patients with POAG were younger (median 68 years) than those with EG (median 74 years). By January 2013, 59 patients with POAG and 48 with EG had died. At death, the patients with POAG were younger (median 81.8 years) than those with EG (87.9 years). In both groups, the women lived longer than the men, but among patients with POAG, women and men died at a younger age than those with EG.

Conclusions

As has been reported previously, life expectancy of patients with EG was longer when compared to those with POAG. Higher death rate among patients with EG is explained by higher median age at baseline.

Cardiovascular involvement in patients with pseudoexfoliation syndrome

AIM

Pseudoexfoliation (PEX) syndrome, diagnosed by ocular examination, is a common disorder of the extracellular matrix. Previous studies have demonstrated accumulation of PEX material in the walls of blood vessels and myocardium. We aimed to investigate whether PEX is associated with cardiovascular involvement using carotid ultrasound measurements and myocardial tissue Doppler imaging (TDI).

METHODS

Thirty-six PEX patients and 34 age-matched and sex-matched healthy controls who had no PEX material were included. Fasting blood samples were taken and the following data were obtained from all cases: myocardial TDI measurements, the mean carotid intima-media thickness (IMT), total carotid plaque area and number.

RESULTS

There were no significant differences between the groups regarding clinical and biochemical data. The peak systolic TDI velocities at the septal (septal S) and lateral annuli (lateral S), and the isovolumic contraction velocity at the lateral annulus [lateral isovolumic contraction velocity (IVC)] were significantly lower in patients with PEX, than in controls (P = 0.001, <0.001 and 0.016, respectively) whereas IMT, total carotid plaque area and number were significantly higher (P = 0.002, 0.035 and 0.033, respectively). In a logistic regression analysis including age, septal S, lateral S, lateral IVC, IMT, total carotid plaque area and number, septal S, lateral S and IMT were significantly associated with PEX, (P = 0.035, 0.011 and 0.035, respectively).

CONCLUSION

Peak systolic TDI velocities were significantly lower and IMT was significantly increased in patients with PEX. However, PEX was weakly associated with carotid plaque measurements.

[PEX syndrome. Clinical diagnosis and systemic manifestations]

As a result of demographic changes pseudoexfoliation (PEX) syndrome, an age-related systemic disorder of the extracellular matrix, will become an increasingly important issue in clinical practice. Apart from its well-known association with cataract and glaucoma, PEX syndrome predisposes to a broad spectrum of spontaneous and surgical ocular complications due to characteristic alterations of all anterior segment tissues. In view of the high risk of glaucoma development and potential complications during cataract surgery, an accurate and early diagnosis of PEX syndrome is of considerable clinical relevance. Since the characteristic central PEX deposits are lacking in up to 50 % of patients, a reliable diagnosis requires pupillary dilation. Early stages of the disease may be recognized on the basis of subtle alterations of the lens surface in addition to poor pupillary dilation and pigment-related signs including pigment dispersion and peripupillary atrophy. Any asymmetric clinical signs, e.g., regarding pupil width, pigmentation, cataract and intraocular pressure, should alert the ophthalmologist to the potential presence of PEX syndrome. Although the description of PEX syndrome as a systemic disorder of the extracellular matrix associated with the deposition of PEX material in the skin, blood vessel walls and various organ systems dates back to the early 1990s, a causal relationship between the abnormal material deposits and systemic diseases has not yet been clearly established. A growing number of smaller studies have found suggestive evidence for associations between PEX syndrome and cardiovascular/cerebrovascular diseases. The current evidence, however, is ambiguous and requires further investigation through multicenter or population-based, prospective, randomized clinical studies.

Serum YKL-40 levels as a novel marker of inflammation and endothelial dysfunction in patients with pseudoexfoliation syndrome

PURPOSE

To evaluate serum levels of YKL-40 in patients with pseudoexfoliation syndrome (PEX) in comparison with those of age- and sex-matched healthy subjects.

METHODS

Forty patients with PEX (PEX group) and 40 age- and sex-matched control subjects (control group) were enrolled in the study. An enzyme immunoassay method using the commercially available test MicroVue YKL-40 was used to measure serum YKL-40 concentration. Systolic and diastolic blood pressures, serum levels of high sensitivity C-reactive protein (hsCRP), total cholesterol, low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), and triglycerides were also examined.

RESULTS

The mean age was 54.4±7.6 (ranging 41-65) years in each group. The mean serum YKL-40 level of the PEX group was significantly higher than that of the control group (P<0.001). In addition, the mean serum HsCRP, total cholesterol, LDL, and triglycerides levels were significantly higher, and mean serum HDL level was significantly lower in the PEX group than in the control group (all P<0.001, excluding both P=0.002 for triglycerides and HDL levels). Further, the mean systolic and diastolic blood pressures were significantly higher in the PEX group than in the control group (P₁=0.001 and P₂=0.01, respectively).

CONCLUSION

We have shown a relationship between PEX and elevated serum levels of YKL-40. We imply that a better understanding of the role of YKL-40 in the pathogenesis of endothelial dysfunction and atherosclerosis is necessary to develop new therapies for preventing or treating PEX. Further studies are warranted to clarify the clinical relevance of these findings.

Renal artery stenosis and abdominal aorta aneurysm in patients with pseudoexfoliation syndrome

PURPOSE

To evaluate the renal arteries and abdominal aorta in patients with pseudoexfoliation syndrome (PEX).

DESIGN

Prospective, case-control study.

METHODS

The study involved 49 patients with PEX and 42 control subjects. Abdominal aorta and renal arteries were examined by Doppler ultrasonography. In both renal arteries (proximal and distal portions) and abdominal aorta, the peak systolic velocity (PSV) was measured. Renal artery stenosis (RAS) was defined as the renal artery PSV >150 cm/s or renal-to-aortic ratio (RAR) >3.0. Patients who had an abdominal aortic diameter >3 cm were recorded. Computed tomographic angiography was performed to confirm these findings in patients with RAS and/or abdominal aorta aneurysm.

RESULTS

The mean PSV in the proximal renal artery was 88.3 cm/s in PEX group and 79.5 cm/s in control group (P=0.314); in distal renal artery was 91.7 cm/s in PEX group and 93.0 cm/s in control group (P=0.794); in abdominal aorta was 76.0 cm/s in PEX group and 65.2 cm/s in control group (P=0.046). RAS was observed in nine patients with PEX and in only one patient without PEX (P=0.017). Seven out of 10 patients with RAS (six patients in PEX group; one patient in control group) had hypertension. Abdominal aorta aneurysm was observed in four patients in PEX group but not in control group (P=0.061).

CONCLUSIONS

Our study has demonstrated that there is a significant association between PEX and RAS. The abdominal aorta aneurysm may be seen in patients with PEX.

Ocular pseudoexfoliation and cardiovascular disease: a national cross-section comparison study

BACKGROUND

Pseudoexfoliation is a systemic disorder characterized by the deposition of extracellular matrix material. The microfibrillar material that gives rise to the condition is visible clinically in the anterior segment of the eye, and is also found in other tissues, including blood vessels, skin, gallbladder, kidneys, lungs, and heart.

AIMS

The present study aims to determine whether ocular pseudoexfoliation is associated with selected cardiovascular diseases.

MATERIALS AND METHODS

A cross-section comparison study was conducted with the help of the Veterans Health Administration databases, using the International Classification of Diseases, Ninth revision, Clinical Modification for pseudoexfoliation of lens capsule and pseudoexfoliation glaucoma. Selected cardiovascular diseases and risk factors for cardiovascular disease were identified using the appropriate medical codes. Patients with primary open-angle glaucoma, chronic sinusitis, and benign prostatic hyperplasia served as the comparison groups. A logistic regression model was used to control for age, gender, race, and major cardiovascular risk factors.

RESULTS

There were 6,046 case patients with pseudoexfoliation; approximately half were diagnosed with pseudoexfoliation glaucoma. Various stages of ischemic heart disease, cardiomyopathy, and aortic aneurysm were significantly associated with ocular pseudoexfoliation, after controlling for age, gender, race, and major cardiovascular risk factors. Associations, in general, were less demonstrable relative to the primary open-angle glaucoma comparison group.

CONCLUSION

Associations of ocular pseudoexfoliation with cardiovascular diseases were generally fewer and less pronounced when compared to patients with primary open-angle glaucoma. These results add to the results of earlier studies, which suggest that open-angle glaucoma itself might be a risk factor for certain cardiovascular disorders.

Endothelial cell markers in patients with pseudoexfoliation syndrome

The aim of the study was the assessment of the von Willebrand antigen (vWF Ag), E-selectin, and P-selectin concentration in blood plasma of patients with pseudoexfoliation syndrome (PEX). The group studied comprised 30 patients with PEX, aged from 50 to 86 years (mean 73, SD ± 8 years). Patients with cardiovascular and cerebrovascular diseases, diabetes mellitus, infectious disease, cancer, renal or liver insufficiency, connective tissue disease, current smoking, and hormone, antiplatelet, hypolipidemic, antioxidant, or antihypertensive drug therapy were excluded from the study. Each subject underwent a complete ophthalmological examination. Venous blood samples from the cubital vein were taken into sodium citrate solution. VWF Ag, sP-selectin, and sE-selectin concentration were determined by a commercially available enzyme-linked immunosorbent assay (MedSystems, Diagnostica Stago/Roche, R&D). Concentrations of vWF Ag, soluble E-selectin, and soluble P-selectin in blood plasma in the study group were compared with the levels in blood plasma in the control group. No significant differences were found between the groups. Our results indicate that there might be no correlation between PEX and such endothelial cell markers as vWF Ag, sP-selectin, and sE-selectin concentrations. Since the study size is limited, further investigations to confirm that there is no association between endothelial dysfunction in PEX and risk of future cardiovascular disease are necessary.

Assessment of myocardial ischaemia using tissue Doppler imaging in pseudoexfoliation syndrome

PURPOSE

Pseudoexfoliation (PEX) syndrome is characterized by the widespread deposition of abnormal extracellular fibrillary material on many ocular and extraocular tissues. We aimed to investigate the association between PEX syndrome and subclinical myocardial ischaemia, using tissue Doppler echocardiography.

METHODS

Thirty-two patients with pseudoexfoliation syndrome (mean age: 66±9 years, 22 men) and 25 healthy individuals (mean age: 67±8 years, 13 men) were included in the study. Patients with overt coronary artery disease, congestive heart failure, valvular heart disease, cardiomyopathy, and left ventricular hypertrophy were excluded from the study. Tissue Doppler imaging was performed at the septal, lateral, anterior, and inferior mitral annuluses. Differences between the groups were evaluated by the unpaired t-test and the Mann-Whitney U-test, with a P-value of <0.05 considered significant.

RESULTS

Baseline clinical characteristics, two-dimensional, and Doppler echocardiography parameters were similar in the PEX and control groups. Peak systolic velocities at the septal, lateral, anterior, and inferior annuluses were significantly lower in patients with PEX syndrome (P<0.001, 0.01, 0.02, and 0.02, respectively). The early diastolic velocity at the septal annulus, and the ratio of early/late diastolic velocity at the lateral annulus were significantly lower in the study group (P=0.03).

CONCLUSION

PEX syndrome is a common disorder of extracellular matrix. Our data suggest that there may also be an association between PEX syndrome and subclinical myocardial ischaemia in patients who have no signs and symptoms of ischaemia. Thus, we think that ophthalmologists should consider informing their PEX syndrome patients' general practitioners about a possible cardiac risk.

Is there any difference in target intraocular pressure for exfoliative glaucoma patients with cardiovascular disease history?

PURPOSE

To investigate if patients with exfoliation glaucoma (XFG) with cardiovascular disease (CVD) require different target intraocular pressure (IOP) compared to patients with XFG with no CVD for long-term stability.

METHODS

A retrospective, multicenter, observational cohort analysis included consecutive patients with XFG from 9 European academic centers, with a minimum of 5 years follow-up.

RESULTS

In 201 patients, there was a statistical difference between progressed and non-progressed patients in mean (p=0.0049) and peak (p=0.015) IOP, variance of IOP (p=0.028), and number of medicine changes/year (p=0.0037). At a mean IOP ≥22 mmHg, patients progressed in 84% (32/38), between 14 and 21 mmHg in 54% (81/151), and at ≤13 mmHg in 33% (4/12). There was no difference in the rate of progression between groups based on CVD history (p=0.65). However, IOP that allowed ≤50% progression rate for patients with mild or no CVD was ≤20-21 mmHg and ≤18 mmHg for patients with severe disease. Further, at IOP ≥20 mmHg, 8% (1/12) of patients with severe CVD remained stable in contrast to 38% (16/42) of patients with mild and 21% (4/19) with no CVD history (p=0.0093). By multivariant regression analysis of the IOP and CVD measures, mean IOP was a risk factor for progression (p=0.0097).

CONCLUSIONS

Although IOP is the main determinant of progression in XFG under treatment, history of severe CVD should be further investigated as potential risk factor for glaucomatous progression.

Association of exfoliation syndrome and central retinal vein occlusion: an ultrastructural analysis

PURPOSE

To evaluate prospectively the frequency with which exfoliation syndrome (XFS) occurs in patients with central retinal vein occlusion (CRVO) by clinical examination and ultrastructural examination of conjunctival biopsy specimens.

METHODS

Prospective observational case series. Thirty-six eyes of 36 consecutive patients with CRVO were investigated for XFS by slit-lamp examination and conjunctival biopsy when XFS was not clinically visible on examination.

RESULTS

A clinical diagnosis of XFS or a positive biopsy result for exfoliation material (XFM) was present in 22 of the 36 patients (61%; 95% confidence interval 45-75%). Twelve of these 22 patients (54%) had a clinical diagnosis of XFS. Aggregates of XFM were identified ultrastructurally in the biopsy specimens in 10 of 24 patients with no clinical signs of XFS (42%). Patients with and without XFS had similar distribution of age, gender, race and prevalence of systemic disorders. Twelve of the 22 (54%) XFS patients had neither glaucoma nor ocular hypertension prior to the CRVO.

CONCLUSION

In accordance with previous retrospective and histological studies, this prospective, in vivo study suggests that CRVO is commonly associated with XFS.

Epidemiology of exfoliation syndrome in the Reykjavik Eye Study

Exfoliation syndrome (XFS) is a major risk factor for glaucoma. It is characterized by a pathological accumulation of polymorphic fibrillar material in the anterior segment of the eye. It is likely that the increase in intraocular pressure (IOP) seen in XFS patients is at least in part because of flakes of material clogging up the trabecular meshwork, and thereby increasing the resistance to outflow and increasing IOP. XFS glaucoma progresses more rapidly, is more resistant to medical treatment and has worse prognosis than other glaucomas. The prevalence of XFS has been found to vary greatly between different studies, raising the possibility of racial and/or environmental modulators. XFS has also been linked to other changes in ophthalmological structures such as; changes in central corneal thickness (CCT), steeper corneal curvature (CC) and nuclear lens opacifications. Some studies have found XFS to be associated with systemic diseases, mostly cardiovascular and cerebrovascular. Exposure to ultra-violet (UV) light has also been investigated as a possible culprit, along with several other plausible factors. The aim of the present study was to determine the prevalence and 5-year incidence of XFS, to establish possible risk factors and/or concomitant symptoms and finally to investigate the relationship between XFS and glaucomatous changes. The Reykjavík Eye Study (RES) is a prospective study based on a random sample from the Icelandic national population sample. The baseline examination was performed in the autumn of 1996, when 1045 persons older than 50 years participated. Of these, 846 (88.2% of survivors) participated in a follow-up 5 years later. All participants went through a standard examination protocol, and answered a comprehensive questionnaire on health and life style. In the prevalence study, XFS was found in 10.7% of subjects, more frequently in women and older persons. Five years later, a further 5.2% of those that participated in the follow-up study and had no signs of XFS at baseline were diagnosed having XFS. We found a strong correlation between IOP and XFS. No difference was found in the anterior segment parameters measured, but there was a significant loss of neural tissue in the XFS as demonstrated by measurements of cup/disk ratio. In conclusion, we find XFS to be frequent among Icelanders, increasing with age and more in women. Our diagnostic criteria are reliable over time. We have also identified possible risk factors that point to a role of antioxidants in the development of XFS. We find changes in corneal curvature and thickness more related to age than XFS.

Is exfoliation syndrome a sign of systemic vascular disease?

Exfoliation syndrome (ES) is an age-related disorder in which greyish-white flakes accumulate in different tissues in the anterior eye. Its pathogenesis is not completely known, but it results in electron-dense microfibrils. The finding that these can be seen outside the eye in many visceral organs inspired the theory that ES might be a part of a generalized disorder. It was postulated that ES might contribute to increased morbidity, mainly of systemic vascular diseases. This review is a summary of the existing knowledge. The prevalence of arterial hypertension (AHT) in elderly populations is > 30%. No differences have been found in the frequency of AHT among patients with ES or exfoliative glaucoma (EG) compared with those with primary open-angle glaucoma (POAG) or no ES. There are conflicting reports of frequencies of ischaemic heart disease (IHD). A recent registry-based study that used uniform criteria for IHD found no difference in the rate of IHD between patients with EG and those with POAG. However, findings of elevated homocysteine levels in the plasma and aqueous humour of patients with ES or EG suggest an increased vascular risk. No studies have yet been conducted to assess possible links between ES and systemic vascular diseases. In a single-blind study, ES was associated with abdominal aortic aneurysm, but this was not found in a large, cross-sectional investigation. The frequency of ES in patients with diabetes mellitus (DM) is only about half of that when compared in patients with no ES or with POAG. This finding warrants further studies. Molecular genetics research has found no common denominator for ES and the vascular diseases. There is no evidence that ES or EG are related to increased mortality for cardiovascular diseases. Further large-scale, randomized clinical studies are required. At present there are no known medical indications that infer an increased systemic vascular risk or imply a need for the complete internal medical examination of a symptom-free patient with newly diagnosed ES in the eye.

Frequency of systemic vascular diseases in patients with primary open-angle glaucoma and exfoliation glaucoma

PURPOSE

Abnormal fibrils can be identified by electron microscopy in the heart, lung, liver, kidney, cerebral meninges and other tissues of patients with exfoliation syndrome (ES). However, a clinical association of ES with arterial hypertension (HT), ischaemic heart disease (IHD), cerebrovascular accidents and aneurysm of the abdominal aorta is debated. We conducted a national registry-based survey to further assess the first two of these associations.

METHODS

We reviewed the records of 519 consecutive patients to whom the Social Insurance Institution of Finland had granted free medication for glaucoma according to national common criteria. The glaucoma was classified either as primary open-angle glaucoma (POAG) or exfoliation glaucoma (EG), masked to any systemic diseases; 20 patients with other types of glaucoma were excluded from the survey. Masked to the type of glaucoma, the registry provided data on free medication similarly granted for HT, IHD and diabetes mellitus (DM), a known modifier of risk for cardiovascular disease. Data were analysed by logistic regression, modelling age, gender and DM as confounders.

RESULTS

The control group of 344 patients with POAG was comparable as regards gender with the study group of 155 patients with EG, but patients with POAG were both younger (mean 69 versus 73 years; P < 0.0001) and had DM twice as often (10% versus 5%; P = 0.05) compared to those with EG. Adjusting for age, gender and presence of DM, no difference in frequency of HT [odds ratio (OR) 0.80 for presence of EG; 95% confidence interval (CI) 0.52-1.23, P = 0.31] or IHD (OR 0.86 for presence of EG; 95% CI 0.49-1.13, P = 0.66) was detected between the two groups.

CONCLUSION

In this population-based registry survey, no difference in frequency of HT or IHD was noted between patients with POAG and EG who had been granted free medication for these chronic diseases according to national common criteria. The frequency of DM was lower among patients with EG, in line with several previous reports.

Decreased cardiovagal regulation in exfoliation syndrome

PURPOSE

To investigate the parasympathetic cardiovascular regulation, baroreflex sensitivity (BRS), and pulse wave velocity (PWV) in exfoliation syndrome (XFS).

METHODS

Heart rate variability indices [standard deviation of all RR intervals (SDNN); the mean of absolute successive differences (RMSSD); the percentage of intervals differing by >50 ms from the preceding interval (pNN50); low frequency power, and high frequency power], as well as BRS and PWV, were determined on 27 consecutive white XFS patients and 20 white control subjects under standard circumstances, with controlled breath rate of 0.25 Hz. The paired t test, the Mann-Whitney U test, and the Fisher exact test were used for comparisons.

RESULTS

There was no significant difference between the XFS and control groups in sex distribution, age, heart rate, blood pressure, body mass index, systemic diseases, or medication. But in XFS patients, SDNN (mean+/-SD, 24+/-7.3 vs. 49+/-16.5 ms), RMSSD (17+/-7.3 vs. 45+/-29.1 ms), pNN50 (1.6%+/-2.5% vs. 17.7%+/-25.9%), high frequency (112+/-109 vs. 479+/-554 ms), and BRS (4.64+/-2.12 vs. 9.49+/-4.76 ms/mm Hg for BRS+ and 5.28+/-2.16 vs. 10.29+/-4.62 ms/mm Hg for BRS-) were all significantly lower than in the control group (P<0.01 for each parameter). Low frequency was also reduced in XFS (72+/-55 vs. 253+/-241 ms) (P=0.027). In XFS, PWV was significantly increased compared with the control group (11.6+/-4.1 vs. 9.3+/-2.2 m/s) (P=0.023).

DISCUSSION

Our results suggest a clinically and statistically significant impairment of cardiovagal regulation and impairment of conduit artery function in XFS patients.

Pseudoexfoliation syndrome prevalence in Greek patients with cataract and its association to glaucoma and coronary artery disease

PURPOSE

To investigate the prevalence of glaucoma and coronary artery disease (CAD) in patients with cataract and pseudoexfoliation (PEX) syndrome.

METHODS

Cross-sectional study of 2140 consecutive patients with cataract admitted at the University Hospital of Patras, Greece, for cataract surgery. Only patients with senile cataract were included in this study. All patients underwent a complete ophthalmological examination that included slit-lamp evaluation with dilated pupil for PEX material in the anterior segment, intraocular pressure (IOP) measurements, and optic disc cup examination. They also underwent an evaluation for CAD by a cardiologist. CAD was considered present if a patient had a history of myocardial infarction, or ischaemia, or abnormal coronary angiography. The patients were classified into two groups: the PEX and the non-PEX group.

RESULTS

One thousand and eighty-eight (50.8%) patients were men and 1052 (49.2%) were women. The overall prevalence of PEX syndrome was found to be 27.9% and it was found to increase with progressing age. Bilateral PEX was more frequent than unilateral PEX, with the percentage of bilateral PEX raising with progressing age. A total of 132 patients (22.1%) in the PEX group exhibited glaucoma, while in the non-PEX group only 2.5% suffered glaucoma. PEX was also found to be positively associated with the risk for CAD among subjects 50 years or older. No association between CAD and glaucoma was found.

CONCLUSIONS

PEX syndrome constitutes a major glaucoma risk factor and a CAD risk factor. Patients with PEX should be informed and examined frequently as the risk is present throughout.

Ocular and systemic pseudoexfoliation syndrome

PURPOSE

To provide an update on most recent developments regarding ocular and systemic manifestations and complications, clinical diagnosis and management, and molecular pathophysiology of pseudoexfoliation (PEX) syndrome, and to discuss future tasks and challenges in this field.

DESIGN

Perspective.

METHODS

Review of recent literature and authors' own clinical and laboratory studies.

RESULTS

PEX syndrome is a common age-related generalized fibrotic matrix process of worldwide significance, which may not only cause severe chronic open-angle glaucoma and cataract, but also a spectrum of other serious spontaneous and surgical intraocular complications. Recent progress and advances have led to (1) improvements in clinical management by understanding the effects of the PEX process on ocular tissues, by refining diagnostic criteria, by applying new treatment regimes, and by developing preventive strategies to reduce surgical complications; (2) increasing evidence for systemic associations of PEX with cardiovascular and cerebrovascular morbidity; and (3) new insights into the molecular pathophysiology by analyzing the composition of PEX material, the differential gene expression of affected tissues, and key factors involved in pathogenesis. The current pathogenetic concept describes PEX syndrome as an elastic microfibrillopathy involving transforming growth factor-beta1, oxidative stress, and impaired cellular protection mechanisms as key pathogenetic factors.

CONCLUSIONS

Future tasks and challenges comprise epidemiologic prevalence and genetic studies of PEX syndrome, prospective randomized clinical and histopathological screening studies on its systemic manifestations and associations, and intensified basic research on differential protein and gene expression, animal and in vitro models, as well as potential biomarkers for PEX syndrome and its associated glaucoma.

Increase of carotid artery stiffness and decrease of baroreflex sensitivity in exfoliation syndrome and glaucoma

AIM

To investigate the distensibility of the common carotid artery (CCA), baroreflex sensitivity (BRS) and its relation to plasma homocysteine concentration in exfoliation syndrome or exfoliation glaucoma (XFS/XFG).

METHODS

Homocysteine concentrations were measured in 30 XFS/XFG patients and 18 age matched controls. In 21 patients and 17 controls the end diastolic diameter of the CCA and pulsatile distension were measured and BRS was calculated.

RESULTS

There was no significant difference between the groups in sex distribution, age, heart rate, blood pressure, systemic diseases, or medication. In XFS/XFG patients homocysteine concentration was significantly elevated (unpaired t test, p = 0.023), and CCA stiffness was higher (p<0.05), while strain, cross sectional compliance coefficient, distensibility, and BRS were significantly reduced compared to the controls (Mann-Whitney U test, p< or =0.013 for each parameter). In XFS/XFG patients a positive correlation was found between age and plasma homocysteine level (Pearson's correlation, r = 0.490, p = 0.007), and a negative correlation between age and BRS (Kendall's correlation r = -0.374, p = 0.021), as well as between homocysteine concentration and BRS (Kendall's correlation r = -0.377, p = 0.024). No correlation was seen between these variables in the control group.

CONCLUSIONS

These results suggest a pathological large artery function as well as altered parasympathetic vascular control in XFS/XFG which increases with age and with higher homocysteine concentration.