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Biomedical subjects

B Muñoz

Publications and source records attributed to B Muñoz.

At least 19 recordsLinked to original sources

Complementary effects of Mediterranean diet and moderate red wine intake on haemostatic cardiovascular risk factors.

OBJECTIVES: To compare the effect of alcohol-free Mediterranean-type diet (MD) and high-fat diet (HFD) on plasma concentration of emergent haemostatic cardiovascular risk factors (HCVRF). Also, to test if red wine supplementation modifies HCVRF, independent of diet. DESIGN, SUBJECTS AND INTERVENTION: Controlled prospective intervention study. Two groups, each of 21 healthy male university students (22+/-3.4 y), received either MD or HFD for 90 days. Between days 30 and 60, both diets were supplemented with 240 ml/day of red wine. Baseline and T30, T60 and T90-day samples were drawn. No drop out from the study was observed. SETTING: University campus and outpatient nutrition clinic. RESULTS: Volunteers on HFD at T30 had increases in pro-coagulants fibrinogen (22%), factor VIIc (9%), and factor VIIIc (4%), and decreases in natural anticoagulants antithrombin III (3%), protein C (11%) and protein S (6%) and of 20% in plasminogen activator inhibitor-1. At the same time, individuals on MD had increases in fibrinogen (4%), antithrombin III (5%), protein C (3%), protein S (2.7%), and decreases in factor VIIIc (9%), and plasminogen activator inhibitor-1 (21%). After adjusting by baseline values, MD was associated with lower plasma fibrinogen (P=0.03), factor VIIc (P=0.034) and factor VIIIc (P=0.0057) and with higher levels of protein S (P=0.013). Red wine supplementation, in both diets, resulted in decreased plasma fibrinogen (P=0.001) and factor VIIc (P=0.05), and increased tissue plasminogen activator antigen (P=0.01) and plasminogen activator inhibitor-1 antigen (P=0.0003). Wine consumption was also associated with significantly (P=0.01) divergent effects on antithrombin III: it decreased by 10% in individuals on HFD but increased slightly in those on MD. No effects of diet or wine were detected in plasma protein C and C-reactive protein. CONCLUSION: MD and moderate consumption of red wine have complementary, mostly beneficial effects on HCVRF.

Adult↗

OmpA genotypic evidence for persistent ocular Chlamydia trachomatis infection in Tanzanian village women.

BACKGROUND: Trachoma is still a significant problem in the developing world. Adult women are at higher risk of developing scarring and trichiasis, the potentially blinding sequelae, compared to men. In part, the higher risk may be due to more frequent infections in women because of their frequent contact with children, the main reservoir of C. trachomatis infection. However, other factors associated with infection, particularly constant infection, in adult women need to be identified. METHODS: A group of 118 women who were infected with C. trachomatis and 118 women who were not infected, but of similar age and trachoma status, were identified in 1996 from a population-based sample of women age 16 and older from eleven villages in Kongwa, Tanzania. This group of 236 was re-contacted three years later to ascertain trachoma status and determine infection status using polymerase chain reaction-enzyme immunoassay (PCR-EIA). Positive samples at both time points were examined for serovar and genotype shift, using ompA sequencing information. RESULTS: Of the original 236 women, 165 (70%) completed exams in 1999. Fifty-eight (35%) of the 165 women were excluded from this analysis because they received antibiotic treatment for trachoma in the six months prior to the second exam. Infection at baseline was the most important predictor of infection three years later (Age-adjusted odds ratio (95% confidence interval) 6.6 (1.8-24.4)). A total of 17 women (16%) were infected at the two examinations, and of the 15 for whom genotyping could be done, 11 (73%) were infected with the same ompA genotype at both time points. Chronically infected women were more likely to have trichiasis, scarring, and active trachoma at baseline than those never infected or infected only once. Only 41% of the chronically infected women were living in houses with infected pre-school children, but 24% were in houses with no children. Four of ten women with trichiasis developed incident corneal opacity over the three years. CONCLUSIONS: The data provide evidence for persistence of infection in a sub-group of women. The strongest predictor of infection at follow-up was baseline infection, and most were infected with the same genotype at both time points. For women with persistent infection, at least half were either not living with children or not living with infected children, suggesting that continual re-exposure from a close family member was less likely. Chronic infection is likely related to both exposure and immunological factors, and these need to be further identified. Inclusion of women in community-based treatment programs, regardless of whether a child is present in the house, is likely to be important in preventing the progression of inflammatory trachoma and scarring to trichiasis.

Adolescent↗

Progression of active trachoma to scarring in a cohort of Tanzanian children.

Risk factors for the incidence of scarring are needed to inform trachoma control programs in countries hyperendemic for this blinding disease. A cohort of pre-school children with constant, severe trachoma, and an age, sex, and neighborhood matched cohort of children without constant severe trachoma were followed for seven years to determine the incidence of scarring. The incidence of scarring in the children with constant severe trachoma was 29.2% versus 9.6% in the comparison group. In a model adjusting for multiple factors, significant predictors of scarring were increasing age, female, and constant severe trachoma (OR = 4.85, 95% CL = 2.05, 11.40). Infection with C. trachomatis at follow up was also associated with scarring in both groups of children. It is likely that these children have a different host response to infection, and represent a subgroup at high risk for the blinding complications of trachoma. Reducing exposure to infection in the community through antibiotics and changes in hygiene practices is still the most promising control strategy.

Child↗

Diabetes and diabetic retinopathy in a Mexican-American population: Proyecto VER.

OBJECTIVES: The prevalence rate of diabetes is probably higher in Hispanics than in Caucasians, although there is controversy about differences in the risk of diabetic retinopathy. The purpose of the study is to determine the prevalence rates of diabetes and diabetic retinopathy in a population-based study of Hispanics aged > or = 40 years. RESEARCH DESIGN AND METHODS: Proyecto VER is a random sample of Hispanic populations aged > or = 40 years in Arizona. A total of 4,774 individuals (71.6% of the eligible sample) completed the examinations. Diabetes was defined as self-report of a physician diagnosis or HbA(1c) value of > or = 7.0%. Diabetic retinopathy was assessed on stereo fundus photographs of fields 1, 2, and 4. RESULTS: The prevalence rate of diabetes in the Hispanic community (individuals > or = 40 years of age) was 22%. The prevalence rate of diabetic retinopathy (DR) was 48%; 32% had moderate to severe nonproliferative and proliferative retinopathy. DR increased with increasing duration of diabetes and increasing level of HbA(1c). The prevalence rate of DR-like changes in the sample of individuals without diabetic retinopathy was 15% and was not associated with hypertension, systolic blood pressure, or diastolic blood pressure. CONCLUSIONS: The prevalence rate of diabetes in this population of Hispanics is high, almost twice that of Caucasians. The prevalence rate of DR is high but similar to reports in a Caucasian population. The prevalence rate of 9% moderate to severe retinopathy in the newly diagnosed group suggests that efforts to improve detection and treatment of diabetes in Hispanics may be warranted.

Adult↗

The association of multiple visual impairments with self-reported visual disability: SEE project.

PURPOSE: This report examines the relationship between psychophysical measures of visual impairment and self-reported difficulty with everyday visual tasks in a population-based sample of individuals 65 years of age and older. METHODS: Community-dwelling residents (n = 2520) of Salisbury, MD, between the ages of 65 and 84 were recruited for the study. Visual acuity under normal and low luminance, contrast and glare sensitivity, stereoacuity, and visual fields were measured. Subjective physical disability was assessed with the Activities of Daily Vision Scale (ADVS). RESULTS: In multiple regression analyses adjusted for demographic factors, cognitive status, depression, and number of comorbid medical conditions, each of the vision tests except low luminance acuity was independently associated with lower ADVS scores. The analyses indicate that a factor of 2 reduction in visual acuity or contrast sensitivity, comparable with that observed in mild to moderate lens opacity, was associated with a three- to fivefold odds of reporting difficulty with daily tasks. Although age alone was a significant risk factor for disability, it was not associated with overall ADVS score, once visual impairment and other chronic medical conditions were taken into account. CONCLUSIONS: Visual acuity, contrast and glare sensitivity, stereoacuity, and visual fields are significant independent risk factors for self-reported visual disability in an older population. Visual impairment defined by acuity alone is not the only dimension of the association with subjective disability. Additional vision measures are required to understand the impact of vision loss on everyday life.

Activities of Daily Living↗

Prevalence of the different types of age-related cataract in an African population.

PURPOSE: To describe the prevalence of different types of cataract and their association with visual acuity in a Tanzanian population aged 40 years and older. METHODS: A prevalence survey for lens opacity, glaucoma, and visual impairment was carried out on all residents age 40 and older of six villages in Kongwa, Tanzania. One examiner graded the lens for presence of nuclear (NSC), posterior subcapsular (PSC), and cortical cataract (CC), using the new WHO Simplified Cataract Grading System. Visual acuity was measured in each eye, both presenting and best corrected, using an illiterate E chart. RESULTS: The proportion of eligible subjects participating was 90% (3268/3641). The prevalence of cataract was as follows: NSC, 15.6%; CC, 8.8%; and PSC, 1.9%. All types of cataract increased with age, from NSC, 1.7%; CC, 2.4%; and PSC, 0.4% for those aged 40 to 49 years to NSC, 59.2%; CC, 23.5%; and PSC, 5.9% for those aged 70 years and older (P < 0.0001 for all cataract types, chi(2) test for trend). Cataract prevalence was higher among women than men for NSC (P = 0.0001), but not for CC (P = 0.15) or PSC (P = 0.25), after adjusting for age. Prevalence rates of visual impairment (BCVA < 6/12), US blindness (< or = 6/60) and WHO blindness (< 6/120) for this population were 13.3%, 2.1%, and 1.3%, respectively. Older age and each of the major types of pure and mixed cataract were independently associated with worse vision in regression modeling. CONCLUSIONS: Unlike African-derived populations in Salisbury and Barbados, NSC rather than CC was most prevalent in this African population. The seeming lower prevalence of CC may to some extent be explained by different grading schemes, differential availability of cataract surgery, the younger mean age of the Tanzanian subjects, and a higher prevalence of NSC in this population.

Adult↗

Mixed lens opacities and subsequent mortality.

BACKGROUND: Previous studies have found an association between cataract or lens opacity and increased risk of mortality. Further work on determining explanatory factors for this association is needed. OBJECTIVES: To determine, in a population-based cohort of older persons, the 2-year risk of death associated with different types of lens opacities; whether an association of mortality and lens opacity is explained by confounding risk factors such as smoking, diabetes, age, race, and sex, which are known to be related to opacity and mortality; whether lens opacity is a marker for health status; and whether there are differences in cause-specific mortality for persons with and without lens opacity. MAIN OUTCOME MEASURE: Two-year mortality rate. METHODS: The Salisbury Eye Evaluation Project consists of a random sample of 2520 residents of Salisbury, Md, aged 65 to 84 years. At baseline, lens photographs were taken to document nuclear, cortical, posterior subcapsular cataract, and mixed opacities. Data on education, smoking, alcohol use, hypertension, diabetes and other comorbid conditions, handgrip strength, and body mass index were also collected. Two-year follow-up was conducted for mortality and cause of death. RESULTS: Nuclear opacity, particularly severe nuclear opacity, and mixed opacities with nuclear were significant predictors of mortality independent of body mass index, comorbid conditions, smoking, age, race, and sex (mixed nuclear: odds ratio, 2.23; 95% confidence interval, 1.26-3.95). CONCLUSION: Lens opacity status is an independent predictor of 2-year mortality, an association that could not be explained by potential confounders.

Aged↗

Causes of blindness and visual impairment in a population of older Americans: The Salisbury Eye Evaluation Study.

OBJECTIVE: To determine the causes of blindness and visual impairment in a population-based sample of older Americans. METHODS: A random sample of 3821 residents of Salisbury, Md, between the ages of 65 and 84 years was identified from Medicare records. Sixty-six percent (2520 persons) agreed to undergo an eye examination; 26% of the participants were African American. The clinical examination included acuity testing with an Early Treatment Diabetic Retinopathy Study chart and standardized refraction testing for those with a visual acuity worse than 20/30, slitlamp and dilated retinal examination by an ophthalmologist, tonometry, lens and fundus photography, and a suprathreshold visual field test. Visual impairment was defined as a best-corrected acuity in the better-seeing eye worse than 20/40 and better than 20/200, while blindness was acuity in the better-seeing eye of 20/200 or worse. For those with a visual acuity worse than 20/40 in either eye, one or more causes were assigned by an ophthalmologist and a final cause for each eye was confirmed by a panel of 3 subspecialty ophthalmologists (O.D.S., H.A.Q., and S.B.B.) based on all available evidence. RESULTS: Bilateral presenting acuity worse than 20/40 increased from 4% in the 65- to 74-year age group to 16% in the 80- to 84-year age group. One third of those with presenting acuity worse than 20/40 improved to 20/40 or better with refraction. Overall, 4.5% had a best-corrected acuity worse than 20/40. African Americans were more likely to remain visually impaired than were whites despite refraction (odds ratio [95% confidence interval], 1.7 [1.1-2.6]). Whites were most often impaired or blind from age-related macular degeneration (1.2% vs 0.5%; P=.09). African Americans had higher rates of impairment and blindness from cataract or posterior capsular opacification (2.7% vs 1.1%; P=.006), glaucoma (0.9% vs 0.1%; P=.006), and diabetic retinopathy (1.2% vs 0.2%; P=. 004). CONCLUSIONS: More than half of those with visual impairment or blindness had conditions that were either surgically treatable or potentially preventable. African Americans had a disproportionate number of blinding diseases, particularly those amenable to eye care intervention. Targeted interventions for specific populations to increase appropriate eye care use would greatly improve vision and function in older Americans. Arch Ophthalmol. 2000;118:819-825

Aged↗

Monocular versus binocular visual acuity as measures of vision impairment and predictors of visual disability.

PURPOSE: To examine the relationship between monocular and binocular visual acuities as predictors of visual disability in a population-based sample of individuals 65 years of age and older. METHODS: Two thousand five hundred twenty community-dwelling residents of Salisbury, Maryland, between the ages of 65 and 84 years of age were recruited for the study. Corrected visual acuity was measured monocularly and binocularly using ETDRS charts. Reading speed, face discrimination, and self-reported difficulty with visual tasks were also determined. RESULTS: Binocular acuity is predicted with reasonable accuracy by acuity in the better eye alone, but not by the widely used American Medical Association (AMA) weighted-average algorithm. The AMA algorithm significantly underestimates binocular acuity when the interocular acuity difference exceeds one line. Monocular acuity and binocular acuity were significantly better predictors of reading speed than the AMA weighted score or a recently proposed Functional Vision Score (FVS). Monocular acuity in the better eye, binocular acuity, and the AMA and FVS algorithms were equally good predictors of self-reported vision disability. None of the acuity measures were good predictors of face recognition ability. CONCLUSIONS: The binocular acuities of older individuals can be inferred from measures of monocular acuity. There is little evidence for binocular inhibition when the monocular acuities in the two eyes are unequal, as opposed to the widely used AMA algorithm for computing binocular visual impairment. For tasks that are strongly associated with visual acuity, such as reading, this association can be captured from measures of monocular acuity and does not require separate assessment of binocular acuity.

Aged↗

Dry eye and dry mouth in the elderly: a population-based assessment.

BACKGROUND: Symptoms of dry eye and dry mouth are common in the elderly and are often debilitating. Previous research on small populations has been inconsistent regarding the contribution to sicca symptoms of autoimmune markers, medication use, and other factors. The objective of this study was to determine the population prevalence of symptoms of dry eye and dry mouth and to evaluate possible risk factors. METHODS: This is a population-based study of 2481 individuals, aged 65 to 84 years, residing in Salisbury, Md, and identified by the Health Care Financing Medicare database. The main outcome measures included information on sicca symptoms, medical history, medication use, and joint examination results collected in a standardized manner. Autoimmune status was assessed in 1200 individuals by measuring antinuclear antibody, rheumatoid factor, and autoantibodies to the soluble nuclear antigens Ro/SS-A and La/SS-B by double immunodiffusion. RESULTS: Approximately 27% of the population reported dry eye or dry mouth symptoms to be present often or all the time and 4.4% reported both. The prevalence of dry mouth (but not dry eye) symptoms increased with age, female sex, and white race. No association of sicca symptoms was found with rheumatoid arthritis, smoking, alcohol consumption, reproductive hormonal status, or the presence of autoantibodies. A strong, dose-response relationship was observed between sicca symptoms and the use of certain medication classes. The proportion of the population prevalence of sicca symptoms attributable to the use of drying medications was estimated at 62% for dry eye and dry mouth and 38% for dry eye or dry mouth symptoms. CONCLUSIONS: Sicca symptoms are common in the elderly, and medication side effects appear to be a major underlying factor. Our results do not indicate an association between autoimmune status and sicca symptoms and do not support immunologic testing in persons with sicca symptoms in the absence of other important systemic features.

Age Factors↗

Who participates in population based studies of visual impairment? The Salisbury Eye Evaluation project experience.

PURPOSE: To describe characteristics of respondents and nonrespondents to a home questionnaire and comprehensive clinical examination in a population of elderly Americans. METHODS: The SEE project is a population-based study of age-related eye diseases, visual impairment, and functional status of individuals aged 65 to 84. Potential participants were identified using the Health Care Financing Administration Medicare data base for Salisbury, MD: After sending out an introductory letter, a trained interviewer visited potential participants in their homes, obtained their consent to participate, administered a short screening interview that included questions about their general health and vision, and administered an extensive questionnaire on their diet, medical history, and difficulty performing activities related to vision. The interviewer then scheduled an appointment for the participants to visit a central site for an exam. Potential participants could fall into one of two refusal groups; refusal to take part in the study before the home questionnaire or prior to the clinic visit. RESULTS: The overall response rate for the clinic visit was 65%. Compared to individuals with complete exams, the two groups of refusals were older, less likely to have any college education, more likely to report poor health status, and more likely to need help with Independent Activities of Daily Living (IADL's). Participants with complete home questionnaires that failed to come to the clinic were more likely to have Mini-Mental scores below 25. There were not significant differences by race, gender, or self reported vision status among the three groups. CONCLUSIONS: Population-based studies requiring an in-clinic examination may selectively under-sample those with health and mental difficulties. These differential responses may introduce bias in the study results and need to be addressed when assessing the burden, type and severity of disease in the community. However, self-report of visual status was similar among refusals and participants in this study on vision.

Activities of Daily Living↗

Incidence of trichiasis in a cohort of women with and without scarring.

BACKGROUND: Blindness from trachoma is a significant problem for many underdeveloped countries. While active trachoma is common in children, trichiasis, the potentially blinding sequella, develops in adulthood and affects mainly women. Little is known about factors associated with the development of trichiasis. METHODS: The 7-year incidence of trichiasis and its association with ocular chlamydia infection was examined in a cohort of women from a hyperendemic area. A total of 4,932 women 18 years and older, living in 11 villages in Central Tanzania, were examined in 1989. A follow-up examination in 1996 was performed on all women with scars living in six of the 11 villages and on a random sample of women without scars from the same villages. Trachoma was graded clinically, chlamydia infection was ascertained at follow-up using polymerase chain reaction-enzyme immunoassay (PCR-EIA). RESULTS: A total 523 of the women with scars and 503 of the women without scars were re-examined. Forty-eight of the women with scars (incidence, 9.2%) and three of the women without scars (0.6%) developed trichiasis in the 7-year period. Prevalence of chlamydia infection was significantly higher in the group with scars (11.7% versus 7.1%). Trichiasis cases were more likely to be older, and to have chlamydia infection at follow-up odds ratio (95% confidence interval) 2.5 (1.1-5.7). CONCLUSION: The 7-year incidence rate in the population with scars was high, over 1% per year. Ocular chlamydia infection was more common in the group with scars at baseline and was also associated with being a trichiasis case, suggesting the importance of potentially long-term chlamydia infection in the progression to trichiasis. Antibiotic distribution programmes for trachoma control should include women with scars.

Adult↗

Vegetarians and cardiovascular risk factors: hemostasis, inflammatory markers and plasma homocysteine.

We studied hemostatic and inflammatory cardiovascular risk factors (CVRF), and total plasma homocysteine (tHcy) in 26 vegetarians (23 lacto- or ovolactovegetarians and 3 vegans), matched by age, sex and socioeconomic status with omnivorous controls. Vegetarians had significantly lower proportion of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids in plasma lipids, significantly shortened bleeding time, and increased blood platelet count and in vitro platelet function (aggregation and secretion). Plasma levels of all coagulation or fibrinolytic factors and natural inhibitors synthesized in the liver were lower in vegetarians than in controls. Whereas for some factors this decrease was statistically significant (fibrinogen, factor VIIc, antithrombin III, protein S, plasminogen) for the remaining (factors VIIIc, Vc, prothrombin, protein C) a trend in the same direction was found. For hemostatic proteins of predominantly extrahepatic origin (von Willebrand factor. tPA, PAI-1) this tendency was not present. No significant differences in inflammatory proteins (C-reactive protein and alpha1-protease inhibitor) were detected in both groups. tHcy was significantly increased in vegetarians, and correlated only with cobalamin levels. The increased platelet function and tHcy found in vegetarians may counteract the known cardiovascular health benefits of vegetarian diet (VD).

Adult↗

Tranexamic acid inhibits fibrinolysis, shortens the bleeding time and improves platelet function in patients with chronic renal failure.

BACKGROUND: A defect in platelet function is the main determinant of the prolonged bleeding time in chronic renal failure (CRF). We previously reported a significant correlation between platelet abnormalities and elevated plasma markers of plasmin and thrombin generation. Our aim was to explore the effect of inhibiting both plasmin action with tranexamic acid (TA) and thrombin production with low molecular weight heparin (LMWH), on the bleeding time (BT) and platelet function in patients with CRF. METHODS: 37 patients with CRF (mean creatinine 8.6 +/- 4.4 mg/dl) under conservative treatment, with prolonged BT, entered this study and received TA during 6 days, with (n = 24) and without LMWH (n = 13). BT, platelet aggregation/secretion, platelet granule contents, von Willebrand factor and parameters of coagulation and fibrinolysis were recorded before and at the end of treatment. RESULTS: The BT was shortened in 26/37 (67%) patients. This effect was associated with significant improvement of platelet aggregation and secretion, with decrease to a normal range of fibrin/fibrinogen degradation products, mild increase in plasmin-antiplasmin complexes and pronounced reduction of circulating plasminogen. No differences were seen among patients with or without LMWH. No serious side effects or complications were observed. INTERPRETATION: These findings indicate that the activation of fibrinolysis plays a significant role in the defect of primary hemostasis in patients with CRF. Inhibition of plasmin activity with TA shortens the BT and improves platelet function in the majority of patients with severe disease.

Antifibrinolytic Agents↗

Racial differences in lens opacities: the Salisbury Eye Evaluation (SEE) project.

The purpose of this study was to determine racial differences in the prevalence of different types of lens opacities and cataract surgery. Between 1993 and 1995, the Salisbury Eye Evaluation (SEE) Project enrolled a representative sample of 2,520 community-dwelling persons aged 65-84 years in Salisbury, Maryland, 26.4% of whom were African-American. Participants received a full eye examination, and photographs were taken for documentation of lens status. Photographs were graded using a standardized grading system for the presence of cortical, nuclear, or posterior subcapsular cataract (PSC) opacification in at least one eye. The odds of having cortical opacities were 4.0 times greater among African Americans than among Caucasians (95% confidence interval (CI) 3.3-4.8). Caucasians were significantly more likely to have nuclear opacities (odds ratio = 2.1, 95% CI 1.7-2.6) and PSC opacities (odds ratio = 2.5, 95% CI 1.7-3.6). The odds of cataract surgery were 2.8 times higher among Caucasians, but these differences did not explain the differences in the prevalence of different types of lens opacities by racial group. With lower rates of nuclear and PSC opacities than Caucasians, African Americans may have a lower demand for cataract surgery. However, even with these differences, there is still significant unnecessary loss of vision due to cataract among older African Americans, for whom programs to ensure access to surgical care are indicated.

Aged↗

Sunlight exposure and risk of lens opacities in a population-based study: the Salisbury Eye Evaluation project.

CONTEXT: Exposure to UV-B radiation in sunlight has been shown to increase the risk of cataract formation in high-risk occupational groups, but risk to the population has not been quantified. OBJECTIVES: To determine the ocular exposure to UV-B radiation in sunlight for a population of older persons and to determine the association between UV-B and lens opacities. DESIGN: The Salisbury Eye Evaluation project, a population-based cohort of older adults. SETTING: Salisbury, Md. PARTICIPANTS: A total of 2520 community-dwelling 65-year-old to 84-year-old adults in Salisbury, Md, from 1993 to 1995, of whom 26.4% were African Americans. MAIN OUTCOME MEASURE: Association of photographically documented cortical opacity 3/16 or greater in at least 1 eye with ocular UV-B exposure, reported in Maryland sun-years of exposure. RESULTS: The odds of cortical opacity increased with increasing ocular exposure to UV-B (odds ratio [OR], 1.10; 95% confidence interval [CI], 1.02-1.20). The relationship was similar for women (OR, 1.14; 95% CI, 1.00-1.30) and for African Americans (OR, 1.18; 95% CI, 1.04-1.33). Analyses of the ocular dose by each age group after the age of 30 years showed no vulnerable age group, suggesting damage is based on cumulative exposure. CONCLUSIONS: Although this population of older Americans has relatively low ocular exposure to UV-B in sunlight, there is still an association between ocular exposure and increasing odds of cortical opacity. Our study found an association among African Americans, which, to our knowledge, has not been reported previously. All sex and racial groups would benefit from simple methods to avoid ocular sun exposure.

Aged↗

Endothelial cell markers in chronic uremia: relationship with hemostatic defects and severity of renal failure.

Plasma von Willebrand factor antigen, soluble thrombomodulin, and tissue factor were increased in 31 patients with severe chronic renal failure (creatinine clearance <20 ml/min) under conservative treatment, whereas plasminogen activator inhibitor antigen did not differ significantly from healthy controls. No correlation among plasma levels of these proteins was found. Three patterns of relationship between endothelial cell markers and hemostatic defects were identified: 1) Plasma thrombomodulin, a marker of endothelium damage, was found an independent predictor of bleeding time and platelet aggregation, and secretion defects, and was also related to the severity of renal failure; 2) von Willebrand factor antigen, an index of endothelial cell activation and secretion, was significantly correlated with intravascular markers of thrombin and plasmin generation and with platelet adenosine triphosphate content, but not with plasma creatinine levels; and 3) tissue factor and plasminogen activator inhibitor antigen levels were not statistically correlated with the diverse hemostatic defects. Activation of coagulation and fibrinolysis, secondary to endothelial cell activation, appearing early during the evolution of chronic renal failure, is pathogenically related to the platelet dysfunction, and probably to development of atherosclerosis and thrombotic events in this disease. The progression of chronic renal failure, through endothelial cell damage, would lead to aggravation of the platelet functional defect potentiating the hemorrhagic risk.

Antigens↗