Biomedical subjects

J M Tielsch

Publications and source records attributed to J M Tielsch.

At least 109 records · Page 6Linked to original sources

PubMed1993

Lifetime prevalence of ocular injuries from the Baltimore Eye Survey.

OBJECTIVE: To estimate the cumulative lifetime prevalence, nature, and consequences of ocular injuries in a multiracial urban environment. METHODS: Self-reported lifetime ocular injuries were ascertained in a population-based sample of persons aged 40 years or older residing in 16 clusters in east Baltimore, Md. A total of 5308 subjects underwent a screening eye examination and were interviewed about lifetime ocular injuries. RESULTS: Eight hundred thirty ocular injury incidents were reported by 762 (14.4%) subjects. The maximum number of ocular injuries reported in a lifetime was four. At least one injury was reported by 22.5% of black men, 20.3% of white men, 12.2% of black women, and 7.7% of white women. No treatment was sought for 18% of these injuries (22% black and 14% white subjects). The prevalence of visual impairment due to trauma per 1000 people was 22.3 among black men, 7.4 among white men, 6.7 among black women, and 3.5 among white women. The prevalence of blindness due to trauma in at least one eye was 21.2 per 1000 among black men, 3.7 times the rate among white men. Based on reports of injuries in the year prior to interview, the annual incidence of medically treated ocular injuries per 1000 people was 5.6 among black men, 4.1 among white men, 5.3 among black women and 1.8 among white women aged 40 years and older. CONCLUSIONS: Lifetime prevalences of ocular injuries were similar among both black and white men, but the visual consequences of the injuries were more severe among black men.

Adolescent↗

PubMed1993

Clustering of xerophthalmia within households and villages.

The clustering of xerophthalmia within households and villages was estimated among preschool age children using data from studies conducted in Malawi, Zambia, Indonesia and Nepal over the past decade. Pairwise odds ratios (OR) were used to measure the magnitude of clustering. This OR measures the risk of xerophthalmia for a preschool child given that another randomly chosen preschool child from the same household (or same village but different household) had xerophthalmia, relative to the risk if that randomly chosen preschool child did not have xerophthalmia. Village pairwise OR ranged from 1.2 in Malawi to 2.2 in Nepal. Household pairwise OR ranged from 4.4 in Malawi to 9.7 in Indonesia, indicating that xerophthalmia clustering was much greater within households than villages. The magnitude of this clustering was as large, or larger than, infectious outcomes such as diarrhoea, fever and cough. Although xerophthalmia was associated with a weekly history of infectious morbidity, the clustering of diarrhoea, fever and cough explained very little of the xerophthalmia clustering observed in each of these studies, Hence, other household factors such as food availability and dietary practices should be examined for their role in the clustering of xerophthalmia within certain households.

Child, Preschool↗

PubMed1993

Automated suprathreshold screening for glaucoma: the Baltimore Eye Survey.

PURPOSE: To evaluate automated suprathreshold perimetric screening for glaucoma in a population-based survey of ocular disorders in east Baltimore, Maryland. METHODS: A population-based sample of persons > or = 40 years of age residing in 16 clusters was selected for an ocular screening examination that included automated suprathreshold testing with the Full Field 120 program of the Humphrey Field Analyzer. Subjects who failed the test underwent manual testing to confirm the defect. Subjects were referred for definitive examination by an ophthalmologist if they had an abnormal field, visual acuity worse than 20/30, intraocular pressure > 21 mm Hg, optic disc damage, a history of glaucoma, or shallow angles. The sensitivity and specificity of the automated visual field testing for identifying glaucoma was estimated and compared with other methods to screen for glaucoma. RESULTS: Of 5,341 subjects > or = 40 years of age who underwent a screening eye examination at neighborhood centers, 4,735 (89%) completed the automated field test. The median test time was 7.25 minutes per eye. Screening test results were abnormal in one or both eyes in 1,234 (26%) of the subjects. Kinetic perimetry was performed on 95% of these subjects, and defects were confirmed for 448 (36%) of them. Hence, 9.5% of the 4,735 subjects who completed the automated test were referred for definitive examination because the defect on automated perimetry was confirmed on manual testing. For a specificity of 90%, the sensitivity of the screening visual field test to detect glaucoma was 52% for 17 or more relative or absolute defects, higher than that of intraocular pressure at 39% for a cut-off of 20.5 mm Hg, vertical cup-to-disc ratio at 45% for a cut-off of 0.53, narrowest remaining rim width at 42% for a cut-off of 0.16, and was comparable to a combination of these and other nonfield parameters. CONCLUSION: Suprathreshold testing performed better than nonperimetry-based screening tests for glaucoma. However, a number of logistical weaknesses of this visual field screening method were identified.

Adult↗

PubMed1992

Agreement between maternal interview- and medical record-based gestational age.

Agreement between maternal interview- and medical record-based gestational age was assessed by using data from a case-control study of childhood strabismus. The sample consisted of 383 cases of strabismus and their age-matched controls, diagnosed between 1985 and 1986 in Baltimore, Maryland, who were under age 7 years when diagnosed. Medical record-based gestational age was derived, in order of priority, from early ultrasound examination, time from the last menstrual period, pediatric examination, and obstetric examination. The intraclass correlation coefficient, kappa, and mean difference were used to compare agreement between maternal interview- and medical record-based gestational age by maternal and pregnancy characteristics and characteristics related to study design. Overall, 86 percent of mothers were within 2 weeks of the gestational age reported in the medical record. The intraclass correlation coefficient comparing maternal and medical record-based gestational age was 0.83 (95% confidence interval 0.80-0.86). Agreement was positively associated with shorter length of recall, low birth order, and having a neonatal illness related to prematurity. Agreement was poor among mothers of healthy preterm infants. There was a weak positive association between recall and some sociodemographic covariates. There was greater misclassification of prematurity in the controls than in the cases. The results suggest that, in general, women recall gestational age well, which supports the use of gestational age derived from maternal interviews.

Baltimore↗

PubMed1992

Ocular trauma in the United States. Eye injuries resulting in hospitalization, 1984 through 1987.

The discharge rate for ocular trauma resulting in hospitalization and variations in rates between US census subdivisions were examined by using hospital discharge abstracts from the 1984 through 1987 National Hospital Discharge Surveys. The average annual rate of hospitalization with a principal diagnosis of ocular trauma was 13.2 per 100,000. The rate for any ocular trauma (principal or secondary diagnosis) was 29.1 per 100,000. Males were three times more likely to be hospitalized for a principal diagnosis of ocular trauma than females. Age-specific rates for principal and secondary diagnoses of ocular trauma were distributed bimodally, with the highest peak in adolescents and young adults, and another peak among those 75 years or older. This study has begun the first step in profiling ocular trauma resulting in hospitalization in the United States.

Adolescent↗

PubMed1992

Maternal cigarette smoking during pregnancy. A risk factor for childhood strabismus.

Strabismus is a common ophthalmologic disorder in children that can result in permanent visual loss. A population-based case-control study was conducted to investigate the association between childhood strabismus and prenatal risk factors including maternal smoking. All incident cases of strabismus diagnosed during a 21-month period, from January 1, 1985, to September 30, 1986, in nine metropolitan area pediatric ophthalmology centers were selected for study (n = 377). Controls were children born on the same day and in the same hospital as the cases (n = 377). Data collection included an interview with the biologic mother and abstraction of obstetric and neonatal birth records. Cigarette smoking was associated with esotropia and but not exotropia for those women who smoked throughout pregnancy (odds ratio, 1.8, 95% confidence interval, 1.1 to 2.8, and odds ratio, 1.4, 95% confidence interval, 0.6 to 3.1, respectively). The relative risk for strabismus was not elevated for women who quit smoking before pregnancy or during pregnancy, nor was there evidence of a dose response. The effect of maternal smoking on risk of esotropia was modified by birth weight and gestational age. The association of maternal smoking throughout pregnancy and esotropia was strongest for children who weighed less than 2500 g (odds ratio, 8.2, 95% confidence interval, 1.1 to 62.7) and 3500 g or more at birth (odds ratio, 5.6, 95% confidence interval, 2.1 to 15.4). Exposure to secondary smoke during pregnancy increased the risk of strabismus only when the mother smoked.

Baltimore↗

PubMed1992

National outcomes of cataract extraction. Increased risk of retinal complications associated with Nd:YAG laser capsulotomy. The Cataract Patient Outcomes Research Team.

PURPOSE: The authors studied 57,103 randomly selected Medicare beneficiaries who underwent extracapsular cataract extraction in 1986 or 1987 to determine the possible association between performance of neodymium (Nd):YAG laser capsulotomy and the risk of subsequent retinal break or detachment. METHODS: Cases of cataract surgery were identified from Medicare claims submitted in 1986 and 1987 and were followed through the end of 1988. Episodes of cataract surgery, posterior capsulotomy, and retinal complications were ascertained based on procedure and diagnosis codes listed in physician bills and hospital discharge records. Lifetable and Cox's proportional hazards models were used to analyze the risk of retinal detachment or break in patients undergoing and not undergoing capsulotomy during the period of observation. RESULTS: Of the 57,103 persons identified as having undergone extracapsular cataract extraction in 1986 or 1987, 13,709 subsequently underwent Nd:YAG laser capsulotomy between 1986 and 1988. A total of 337 persons had aphakic or pseudophakic retinal detachments between 1986 and 1988 and an additional 194 underwent repair of a retinal break. Proportional hazards modeling shows a 3.9-fold increase in the risk of retinal break or detachment among those who underwent capsulotomy (95% confidence interval: 2.89 to 5.25). Younger patient age, male sex, and white race also were associated with increased risk of retinal complications after extracapsular cataract extraction. CONCLUSION: The authors conclude that there is a statistically significant increase in the risk of retinal detachment or break in those patients who undergo capsulotomy after cataract extraction. Therefore, capsulotomy should be deferred until the patient's impairment caused by capsular opacification warrants the increased risk of retinal complications associated with performance of capsulotomy.

Aged↗

PubMed1992

Calf lung surfactant extract prophylaxis and retinopathy of prematurity.

Retinopathy of prematurity (ROP) is an important cause of blindness among extremely low birth weight infants (birth weight less than or equal to 1000 g). In the 1990s, greater numbers of extremely low birth weight infants will survive, in part due to routine surfactant replacement therapy for neonatal respiratory distress syndrome. Few studies have evaluated the effect of surfactant therapy on the incidence and severity of ROP. The authors performed a review of the records of extremely low birth weight infants born in two 2-year intervals before and after initiation of a clinical protocol in which all extremely low birth weight infants received prophylactic treatment with calf lung surfactant extract (Infasurf). Surfactant therapy was associated with a significant improvement in survival to discharge (79% [88 of 112] versus 63% [82 of 131]; P = 0.01). Compared with control infants, surfactant-treated infants had a significantly lower incidence of any stage of ROP (64% [56 of 87] versus 85% [68 of 80]; P less than 0.004). The incidence of threshold (Stage 3 plus or greater) ROP was substantially reduced (3.4% [3 of 87] versus 10% [8 of 80]; P = 0.16)). The surfactant-associated reduction in ROP was independent of birth weight, gestational age, race, or sex. These data suggest that Infasurf may substantially reduce the incidence and severity of ROP in the extremely low birth weight population.

Bronchopulmonary Dysplasia↗

PubMed1992

Xerophthalmia and growth in preschool Indonesian children.

Approximately 4000 preschool children in West Java, Indonesia, were examined for xerophthalmia and weighed and measured at 3-mo intervals from March 1977 to December 1978. Children recovering from xerophthalmia over a 3-mo interval gained an average of 124 g (95% CI 42-206) more over 3 mo than normal children. Their height gain was similar to normal children's. Children who developed xerophthalmia during a 3-mo period gained 199 g (95% CI 114-313) less and grew 0.28 cm (95% CI 0.12, 0.44) less than their normal peers. Children with chronic xerophthalmia gained 120 g (95% CI 49-191) less and grew 0.21 cm (95% CI 0.05-0.37) less than normal children. These data suggest that linear and ponderal growth is adversely affected by chronic and incident xerophthalmia, but that catch-up ponderal growth is experienced by children recovering from xerophthalmia.

Body Height↗

PubMed1991

A population-based evaluation of glaucoma screening: the Baltimore Eye Survey.

The Baltimore Eye Survey was a population-based survey conducted from January 1985 to November 1988 among residents of east Baltimore, Maryland, who were 40 years of age or older. A total of 5,308 black subjects and white subjects received a comprehensive screening examination for glaucoma including tonometry, visual fields, stereoscopic fundus photography, and a detailed medical and ophthalmic history. Based on a definitive examination, a diagnosis of glaucoma of any type was made for 196 persons. Tonometry, cup:disc ratio, and narrowest neuroretinal rim width were evaluated for their ability to correctly classify subjects into diseased or nondiseased states. There were no cutoff values at which these variables provided a reasonable balance of sensitivity and specificity, separately or in combination. Logistic regression models were fit that included demographic and other risk factors. Sensitivities and specificities were calculated for varying cutoff levels on the distribution of predicted probabilities. There was no cutoff for which reasonable sensitivity and specificity were obtained. The authors conclude that the effectiveness of current techniques for glaucoma screening is limited.

Adult↗

PubMed1991

Racial differences in the cause-specific prevalence of blindness in east Baltimore.

BACKGROUND: Bilateral blindness unrelated to simple refractive error is twice as prevalent among blacks as among whites, although the difference narrows among the elderly. The reasons for this race- and age-related pattern are uncertain. METHODS AND RESULTS: A randomly selected, stratified, multistage cluster sample of 2395 blacks and 2913 whites 40 years of age and older in East Baltimore underwent detailed ophthalmic examinations by a single team. We identified 64 subjects who were blind in both eyes. The leading causes of blindness were unoperated senile cataract (accounting for blindness in 27 of the total of 128 eyes), primary open-angle glaucoma (17 eyes), and age-related macular degeneration (16 eyes). Together, these three disorders accounted for 47 percent of all blindness in this sample. Unoperated cataract accounted for 27 percent of all blindness among blacks, among whom it was four times more common than among whites; whites were almost 50 percent more likely than blacks to have undergone cataract extraction before the age of 80 (P less than 0.002). Primary open-angle glaucoma accounted for 19 percent of all blindness among blacks; it was six times as frequent among blacks as among whites and began 10 years earlier, on average. By contrast, age-related macular degeneration resulting in blindness was limited to whites, among whom it was the leading cause of blindness (prevalence, 2.7 per 1000; 95 percent confidence interval, 1.2 to 5.4); it affected 3 percent of all white subjects 80 years of age or older. CONCLUSIONS: The pattern of blindness in urban Baltimore appears to be different among blacks and whites. Whites are far more likely to have age-related macular degeneration, and blacks to have primary open-angle glaucoma. The high rate of unoperated cataracts among younger blacks and among elderly subjects of both races suggests that health services are underused. Half of all blindness in this urban population is probably preventable or reversible.

Adult↗

PubMed1991

Racial variations in the prevalence of primary open-angle glaucoma. The Baltimore Eye Survey.

OBJECTIVE: --To compare the prevalence of primary open-angle glaucoma between black and white Americans. DESIGN, SETTING, AND PARTICIPANTS: --The design was a population-based prevalence survey of a noninstitutionalized black and white population aged 40 years or older from the eastern and southeastern health districts of Baltimore, Md. A multistage random sampling strategy was used to identify 7104 eligible participants, of whom 5308 (2395 blacks, 2913 whites) received an ophthalmologic screening examination. Those with abnormalities were referred for definitive diagnostic evaluation. MAIN OUTCOME MEASURE: --Primary open-angle glaucoma was defined based on evidence of glaucomatous optic nerve damage, including abnormal visual fields and/or severe optic disc cupping, and was independent of intraocular pressure. MAIN RESULTS: --Age-adjusted prevalence rates for primary open-angle glaucoma were four to five times higher in blacks as compared with whites. Rates among blacks ranged from 1.23% in those aged 40 through 49 years to 11.26% in those 80 years or older, whereas rates for whites ranged from 0.92% to 2.16%, respectively. There was no difference in rates of primary open-angle glaucoma between men and women for either blacks or whites in this population. Based on these data, an estimated 1.6 million persons aged 40 years or older in the United States have primary open-angle glaucoma. CONCLUSIONS: --Black Americans are at higher risk of primary open-angle glaucoma than their white neighbors. This may reflect an underlying genetic susceptibility to this disease and indicates that additional efforts are needed to identify and treat this sight-threatening disorder in high-risk communities.

Adult↗

PubMed1991

Efficacy of vitamin A in reducing preschool child mortality in Nepal.

Community trials of the efficacy of vitamin A supplementation in reducing preschool childhood mortality have produced conflicting results. To resolve the question, a randomised, double-masked, placebo-controlled community trial of 28,630 children aged 6-72 months was carried out in rural Nepal, an area representative of the Gangetic flood plain of South Asia. Randomisation was carried out by administrative ward; the vitamin-A-supplemented children received 60,000 retinol equivalents every 4 months and placebo-treated children received identical capsules containing 300 retinol equivalents. After 12 months, the relative risk of death in the vitamin-A-supplemented compared with the control group was 0.70 (95% confidence interval 0.56-0.88), equivalent to a 30% reduction in mortality. The trial, which had been planned to last 2 years, was discontinued. The reduction in mortality was present in both sexes (relative risk for boys 0.77; for girls 0.65), at all ages (range of relative risks 0.83-0.50), and throughout the year (0.76-0.67). The reduction in mortality risk was not affected by acute nutritional status, as measured by arm circumference. Thus, periodic vitamin A delivery in the community can greatly reduce child mortality in developing countries.

Adult↗

PubMed1991

Occupational lead exposure and strabismus in offspring: a case-control study.

The authors conducted a population-based case-control study to investigate the association between strabismus and parental occupational lead exposure. Cases were children diagnosed with nonrestrictive strabismus between 1985 and 1986 at Baltimore, Maryland-area pediatric ophthalmology practices and clinics (n = 377). Controls were matched for age and hospital of birth (n = 377). Jobs held by parents were assessed for lead exposure by industrial hygienists. The time window for lead exposure was defined as the period from conception through age 9 months. The unadjusted odds ratio for maternal lead exposure and the esotropic form of strabismus was 2.6 (95% confidence interval (CI) 0.4-27). Unadjusted odds ratios for paternal occupational lead exposure and esotropia were 1.0 (95% CI 0.5-2.1) for low exposure, 2.1 (95% CI 0.9-5.3) for moderate exposure, and 1.2 (95% CI 0.4-3.3) for high exposure. The study results suggest the possibility of a weak association between paternal lead exposure and strabismus in offspring.

Amblyopia↗

PubMed1991

Socioeconomic status and visual impairment among urban Americans. Baltimore Eye Survey Research Group.

The Baltimore Eye Survey is a population-based study of ocular disorders conducted in East Baltimore, Md, designed to determine the prevalence and severity of vision loss and ocular disease and their relationships to socioeconomic and other risk factors. This survey comprised 5300 subjects (2911 whites and 2389 blacks). Visual impairment was associated with age, race, general health status, educational level, income, and employment status. An identified association of race with blindness and visual impairment was reduced, but not eliminated, after adjustment for these socioeconomic factors, indicating that socioeconomic status itself is an important determinant of visual impairment.

Adult↗

PubMed1991

Relationship between intraocular pressure and primary open angle glaucoma among white and black Americans. The Baltimore Eye Survey.

A detailed ocular examination, including perimetry, was conducted on 5308 black and white subjects aged 40 years and older in a population-based prevalence survey in east Baltimore, Md. Repeated, detailed examinations were carried out on selected subjects. Roughly half of all subjects with optic nerve damage from primary open angle glaucoma, regardless of race, were unaware that they had the condition. The average intraocular pressure (IOP) among black patients with glaucoma who were receiving treatment was virtually identical to that in those black patients who were not receiving treatment (median IOP, 20 mm Hg); treated eyes of white patients had a lower IOP than those eyes of white patients who were not receiving treatment (mean [+/- SD] IOP, 18.69 +/- 3.23 mm Hg vs 24.15 +/- 5.23 mm Hg; P less than .001). The risk of glaucomatous optic nerve damage increased with the height of the screening IOP, particularly at levels of 22 to 29 and 30 mm Hg and above (relative rate compared with IOP of 15 mm Hg or lower, 12.8 and 40.1 mm Hg, respectively). More than half of all glaucomatous eyes had a screening IOP below 21 mm Hg, whether these eyes were receiving treatment or not. The IOP in glaucomatous eyes tended to rise on follow-up, in contrast with nonglaucomatous eyes in which the IOP was as likely to rise as to fall. Results confirmed that IOP is an important factor in glaucoma, but did not support the traditional distinction between "normal" and "elevated" pressure, nor its corollaries, "low-tension" glaucoma and "high-tension" glaucoma.

Black People↗

PubMed1990

Visual impairment in a rural Appalachian community. Prevalence and causes.

A population-based survey of 1136 subjects aged 40 years and older was conducted in a rural valley of Kentucky to determine the nature and extent of visual disability in an underserved area of rural America. Data on corrected visual acuity and ocular history, along with demographic, socioeconomic, and health care utilization parameters, were gathered. Those subjects with an acuity below 20/60 in either eye underwent a comprehensive ophthalmologic examination. The prevalence of binocular blindness (acuity worse than 20/400 in the better eye) was 0.44% and of monocular blindness (acuity worse than 20/400 in one eye) was 3.3%, approximately twice the national rates. The chief cause of bilateral visual impairment was macular degeneration among men and cataract among women. Cataract, trauma, and amblyopia were the major causes of monocular visual impairment in both sexes. Risk factor analysis revealed younger age, higher education, active employment, access to a health care facility, and comprehensive health insurance coverage to be inversely associated with visual impairment.

Adult↗

PubMed1990

Blindness and visual impairment in an American urban population. The Baltimore Eye Survey.

Data on the prevalence of blindness and visual impairment in multiracial urban populations of the United States are not readily available. The Baltimore Eye Survey was designed to address this lack of information and provide estimates of prevalence in age-race subgroups that had not been well studied in the past. A population-based sample of 5300 blacks and whites from east Baltimore, Md, received an ophthalmologic screening examination that included detailed visual acuity measurements. Blacks had, on average, a twofold excess prevalence of blindness and visual impairment than whites, irrespective of definition. Rates rose dramatically with age for all definitions of vision loss, but there was no difference in prevalence by sex. More than 50% of subjects improved their presenting vision after refractive correction, with 7.5% improving three or more lines. Rates in Baltimore are as high or higher than those reported from previous studies. National projections indicate that greater than 3 million persons are visually impaired, 890,000 of whom are bilaterally blind by US definitions.

Adult↗