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Featured researches published by Joanne Katz.


The Lancet | 2013

Maternal and child undernutrition and overweight in low-income and middle-income countries

Robert E. Black; Cesar G. Victora; Susan P Walker; Zulfiqar A. Bhutta; Parul Christian; Mercedes de Onis; Majid Ezzati; Sally Grantham-McGregor; Joanne Katz; Reynaldo Martorell; Ricardo Uauy

Maternal and child malnutrition in low-income and middle-income countries encompasses both undernutrition and a growing problem with overweight and obesity. Low body-mass index, indicative of maternal undernutrition, has declined somewhat in the past two decades but continues to be prevalent in Asia and Africa. Prevalence of maternal overweight has had a steady increase since 1980 and exceeds that of underweight in all regions. Prevalence of stunting of linear growth of children younger than 5 years has decreased during the past two decades, but is higher in south Asia and sub-Saharan Africa than elsewhere and globally affected at least 165 million children in 2011; wasting affected at least 52 million children. Deficiencies of vitamin A and zinc result in deaths; deficiencies of iodine and iron, together with stunting, can contribute to children not reaching their developmental potential. Maternal undernutrition contributes to fetal growth restriction, which increases the risk of neonatal deaths and, for survivors, of stunting by 2 years of age. Suboptimum breastfeeding results in an increased risk for mortality in the first 2 years of life. We estimate that undernutrition in the aggregate--including fetal growth restriction, stunting, wasting, and deficiencies of vitamin A and zinc along with suboptimum breastfeeding--is a cause of 3·1 million child deaths annually or 45% of all child deaths in 2011. Maternal overweight and obesity result in increased maternal morbidity and infant mortality. Childhood overweight is becoming an increasingly important contributor to adult obesity, diabetes, and non-communicable diseases. The high present and future disease burden caused by malnutrition in women of reproductive age, pregnancy, and children in the first 2 years of life should lead to interventions focused on these groups.


The New England Journal of Medicine | 1991

Racial Differences in the Cause-Specific Prevalence of Blindness in East Baltimore

Alfred Sommer; James M. Tielsch; Joanne Katz; Harry A. Quigley; John D. Gottsch; Jonathan C. Javitt; James F. Martone; Richard M. Royall; Kathe Witt; Sandi Ezrine

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.


Ophthalmology | 1992

An Evaluation of Optic Disc and Nerve Fiber Layer Examinations in Monitoring Progression of Early Glaucoma Damage

Harry A. Quigley; Joanne Katz; Robert J. Derick; Donna Gilbert; Alfred Sommer

From annual examinations of 813 ocular hypertensive eyes, the authors compared optic disc and nerve fiber layer photographs in 2 age-matched subgroups: 37 eyes that converted to abnormal visual field tests at the end of a 5-year period and 37 control eyes that retained normal field tests. Disc change was detected in only 7 of 37 (19%) converters to field loss and in 1 of 37 (3%) controls. Progressive nerve fiber layer atrophy was observed in 18 of 37 (49%) converters and in 3 of 37 (8%) controls. Serial nerve fiber layer examination was more sensitive than color disc evaluation in the detection of progressive glaucoma damage at this early stage of glaucoma. The evaluation of cup-to-disc ratio or of the nerve fiber layer appearance in the initial photograph taken 5 years before field loss were equally predictive of future field damage. The position of nerve fiber layer defects was highly correlated with the location of subsequent visual field loss.


BMJ | 1999

Double blind, cluster randomised trial of low dose supplementation with vitamin A or β carotene on mortality related to pregnancy in Nepal

Keith P. West; Joanne Katz; Subarna K. Khatry; Steven C. LeClerq; Elizabeth Kimbrough Pradhan; Sharada Ram Shrestha; Paul B. Connor; Sanu Maiya Dali; Parul Christian; Ram Prasad Pokhrel; Alfred Sommer

Abstract Objective: To assess the impact on mortality related to pregnancy of supplementing women of reproductive age each week with a recommended dietary allowance of vitamin A, either preformed or as βcarotene. Design: Double blind, cluster randomised, placebo controlled field trial. Setting: Rural southeast central plains of Nepal (Sarlahi district). Subjects: 44646 married women, of whom 20119 became pregnant 22189 times. Intervention: 270 wards randomised to 3groups of 90each for women to receive weekly a single oral supplement of placebo, vitamin A (7000¼g retinol equivalents) or βcarotene (42mg, or 7000¼g retinol equivalents) for over 31/2 years. Main outcome measures: All cause mortality in women during pregnancy up to 12weekspost partum (pregnancy related mortality) and mortality during pregnancy to 6weeks postpartum, excluding deaths apparently related to injury (maternal mortality). Results: Mortality related to pregnancy in the placebo, vitamin A, and βcarotene groups was 704,426,and 361deaths per 100000 pregnancies, yielding relative risks (95% confidence intervals) of 0.60(0.37to 0.97) and 0.51(0.30to 0.86). This represented reductions of 40% (P<0.04)and 49% (P<0.01) among those who received vitamin A and βcarotene. Combined, vitaminA or βcarotene lowered mortality by 44% (0.56(0.37to 0.84), P<0.005) and reduced the maternal mortality ratio from 645to 385deaths per 100000 live births, or by 40% (P<0.02). Differences in cause of death could not be reliably distinguished between supplemented and placebo groups. Conclusion: Supplementation of women with either vitamin A or βcarotene at recommended dietary amounts during childbearing years can lower mortality related to pregnancy in rural, undernourished populations of south Asia.


BMJ | 2003

Effects of alternative maternal micronutrient supplements on low birth weight in rural Nepal: double blind randomised community trial

Parul Christian; Subarna K. Khatry; Joanne Katz; Elizabeth Kimbrough Pradhan; Steven C. LeClerq; Sharada Ram Shrestha; Ramesh Adhikari; Alfred Sommer; Keith P. West

Abstract Objective: To assess the impact on birth size and risk of low birth weight of alternative combinations of micronutrients given to pregnant women. Design: Double blind cluster randomised controlled trial. Setting: Rural community in south eastern Nepal. Participants: 4926 pregnant women and 4130 live born infants. Interventions: 426 communities were randomised to five regimens in which pregnant women received daily supplements of folic acid, folic acid-iron, folic acid-iron-zinc, or multiple micronutrients all given with vitamin A, or vitamin A alone (control). Main outcome measures: Birth weight, length, and head and chest circumference assessed within 72 hours of birth. Low birth weight was defined <2500 g. Results: Supplementation with maternal folic acid alone had no effect on birth size. Folic acid-iron increased mean birth weight by 37 g (95% confidence interval −16 g to 90 g) and reduced the percentage of low birthweight babies (<2500 g) from 43% to 34% (16%; relative risk=0.84, 0.72 to 0.99). Folic acid-iron-zinc had no effect on birth size compared with controls. Multiple micronutrient supplementation increased birth weight by 64 g (12 g to 115 g) and reduced the percentage of low birthweight babies by 14% (0.86, 0.74 to 0.99). None of the supplement combinations reduced the incidence of preterm births. Folic acid-iron and multiple micronutrients increased head and chest circumference of babies, but not length. Conclusions: Antenatal folic acid-iron supplements modestly reduce the risk of low birth weight. Multiple micronutrients confer no additional benefit over folic acid-iron in reducing this risk. What is already known on this topic Deficiencies in micronutrients are common in women in developing countries and have been associated with low birth weight and preterm delivery What this study adds In rural Nepal maternal supplementation with folic acid-iron reduced the incidence of low birth weight by 16% A multiple micronutrient supplement of 14 micronutrients, including folic acid, iron, and zinc, reduced low birth weight by 14%, thus conferring no advantage over folic acid-iron


BMC Public Health | 2013

The associations of parity and maternal age with small-for-gestational-age preterm and neonatal and infant mortality: a meta-analysis.

Naoko Kozuki; Anne C C Lee; Mariangela Freitas da Silveira; Ayesha Sania; Joshua P. Vogel; Linda S. Adair; Fernando C. Barros; Laura E. Caulfield; Parul Christian; Wafaie W. Fawzi; Jean H. Humphrey; Lieven Huybregts; Aroonsri Mongkolchati; Robert Ntozini; David Osrin; Dominique Roberfroid; James M. Tielsch; Anjana Vaidya; Robert E. Black; Joanne Katz

BackgroundPrevious studies have reported on adverse neonatal outcomes associated with parity and maternal age. Many of these studies have relied on cross-sectional data, from which drawing causal inference is complex. We explore the associations between parity/maternal age and adverse neonatal outcomes using data from cohort studies conducted in low- and middle-income countries (LMIC).MethodsData from 14 cohort studies were included. Parity (nulliparous, parity 1-2, parity ≥3) and maternal age (<18 years, 18-<35 years, ≥35 years) categories were matched with each other to create exposure categories, with those who are parity 1-2 and age 18-<35 years as the reference. Outcomes included small-for-gestational-age (SGA), preterm, neonatal and infant mortality. Adjusted odds ratios (aOR) were calculated per study and meta-analyzed.ResultsNulliparous, age <18 year women, compared with women who were parity 1-2 and age 18-<35 years had the highest odds of SGA (pooled adjusted OR: 1.80), preterm (pooled aOR: 1.52), neonatal mortality (pooled aOR: 2.07), and infant mortality (pooled aOR: 1.49). Increased odds were also noted for SGA and neonatal mortality for nulliparous/age 18-<35 years, preterm, neonatal, and infant mortality for parity ≥3/age 18-<35 years, and preterm and neonatal mortality for parity ≥3/≥35 years.ConclusionsNulliparous women <18 years of age have the highest odds of adverse neonatal outcomes. Family planning has traditionally been the least successful in addressing young age as a risk factor; a renewed focus must be placed on finding effective interventions that delay age at first birth. Higher odds of adverse outcomes are also seen among parity ≥3 / age ≥35 mothers, suggesting that reproductive health interventions need to address the entirety of a woman’s reproductive period.FundingFunding was provided by the Bill & Melinda Gates Foundation (810-2054) by a grant to the US Fund for UNICEF to support the activities of the Child Health Epidemiology Reference Group.


Ophthalmology | 1996

The Cause-specific Prevalence of Visual Impairment in an Urban Population: The Baltimore Eye Survey

Bahram Rahmani; James M. Tielsch; Joanne Katz; John D. Gottsch; Harry A. Quigley; Jonathan C. Javitt; Alfred Sommer

BACKGROUND Whereas population-based data on the causes of bilateral blindness have been reported, little information is available on the distribution of causes of central vision loss less severe than the criteria used to define legal blindness. This visual impairment is responsible for a high proportion of eye care service use and results in important reductions in functional status. METHODS Data from the Baltimore Eye Survey were used to estimate the cause-specific prevalence of visual impairment (best-corrected visual acuity worse than 20/40 but better than 20/200) among black and white residents of east Baltimore who were 40 years of age or older. Eligible subjects underwent a screening examination at a neighborhood location and, for those whose best-corrected visual acuity was less than 20/30, a definitive ophthalmologic examination at the Wilmer Eye Institute. RESULTS The prevalence of visual impairment was 2.7% in whites and 3.3% in blacks; the age-adjusted relative prevalence (B/W) was 1.75 (P = 0.01). The leading causes of visual impaired eyes were cataract (35.8%), age-related macular degeneration (14.2%), diabetic retinopathy (6.6%), glaucoma (4.7%), and other retinal disorders (7.3%). Cataract, diabetic retinopathy, and glaucoma were more common as a cause of visual impairment among blacks, whereas macular degeneration was more frequent among whites. More than 50% of all subjects had the potential for improvement in vision with appropriate surgical intervention. CONCLUSION Visual impairment is a prevalent condition among inner city adults 40 years of age or older. The distribution of causes suggests that improvements in the visual health of the population could be achieved with more effective delivery of efficacious ophthalmologic care.


The Lancet | 2013

Mortality risk in preterm and small-for-gestational-age infants in low-income and middle-income countries: a pooled country analysis

Joanne Katz; Anne C C Lee; Naoko Kozuki; Joy E Lawn; Simon Cousens; Hannah Blencowe; Majid Ezzati; Zulfiqar A. Bhutta; Tanya Marchant; Barbara Willey; Linda S. Adair; Fernando C. Barros; Abdullah H. Baqui; Parul Christian; Wafaie W. Fawzi; Rogelio Gonzalez; Jean H. Humphrey; Lieven Huybregts; Patrick Kolsteren; Aroonsri Mongkolchati; Luke C. Mullany; Richard Ndyomugyenyi; Jyh Kae Nien; David Osrin; Dominique Roberfroid; Ayesha Sania; Christentze Schmiegelow; Mariangela Freitas da Silveira; James M. Tielsch; Anjana Vaidya

BACKGROUND Babies with low birthweight (<2500 g) are at increased risk of early mortality. However, low birthweight includes babies born preterm and with fetal growth restriction, and not all these infants have a birthweight less than 2500 g. We estimated the neonatal and infant mortality associated with these two characteristics in low-income and middle-income countries. METHODS For this pooled analysis, we searched all available studies and identified 20 cohorts (providing data for 2,015,019 livebirths) from Asia, Africa, and Latin America that recorded data for birthweight, gestational age, and vital statistics through 28 days of life. Study dates ranged from 1982 through to 2010. We calculated relative risks (RR) and risk differences (RD) for mortality associated with preterm birth (<32 weeks, 32 weeks to <34 weeks, 34 weeks to <37 weeks), small-for-gestational-age (SGA; babies with birthweight in the lowest third percentile and between the third and tenth percentile of a US reference population), and preterm and SGA combinations. FINDINGS Pooled overall RRs for preterm were 6·82 (95% CI 3·56-13·07) for neonatal mortality and 2·50 (1·48-4·22) for post-neonatal mortality. Pooled RRs for babies who were SGA (with birthweight in the lowest tenth percentile of the reference population) were 1·83 (95% CI 1·34-2·50) for neonatal mortality and 1·90 (1·32-2·73) for post-neonatal mortality. The neonatal mortality risk of babies who were both preterm and SGA was higher than that of babies with either characteristic alone (15·42; 9·11-26·12). INTERPRETATION Many babies in low-income and middle-income countries are SGA. Preterm birth affects a smaller number of neonates than does SGA, but is associated with a higher mortality risk. The mortality risks associated with both characteristics extend beyond the neonatal period. Differentiation of the burden and risk of babies born preterm and SGA rather than with low birthweight could guide prevention and management strategies to speed progress towards Millennium Development Goal 4--the reduction of child mortality. FUNDING Bill & Melinda Gates Foundation.


The Lancet | 2006

Topical applications of chlorhexidine to the umbilical cord for prevention of omphalitis and neonatal mortality in southern Nepal: a community-based, cluster-randomised trial

Luke C. Mullany; Gary L. Darmstadt; Subarna K. Khatry; Joanne Katz; Steven C. LeClerq; Shardaram Shrestha; Ramesh Adhikari; James M. Tielsch

BACKGROUND Omphalitis contributes to neonatal morbidity and mortality in developing countries. Umbilical cord cleansing with antiseptics might reduce infection and mortality risk, but has not been rigorously investigated. METHODS In our community-based, cluster-randomised trial, 413 communities in Sarlahi, Nepal, were randomly assigned to one of three cord-care regimens. 4934 infants were assigned to 4.0% chlorhexidine, 5107 to cleansing with soap and water, and 5082 to dry cord care. In intervention clusters, the newborn cord was cleansed in the home on days 1-4, 6, 8, and 10. In all clusters, the cord was examined for signs of infection (pus, redness, or swelling) on these visits and in follow-up visits on days 12, 14, 21, and 28. Incidence of omphalitis was defined under three sign-based algorithms, with increasing severity. Infant vital status was recorded for 28 completed days. The primary outcomes were incidence of neonatal omphalitis and neonatal mortality. Analysis was by intention-to-treat. This trial is registered with , number NCT00109616. FINDINGS Frequency of omphalitis by all three definitions was reduced significantly in the chlorhexidine group. Severe omphalitis in chlorhexidine clusters was reduced by 75% (incidence rate ratio 0.25, 95% CI 0.12-0.53; 13 infections/4839 neonatal periods) compared with dry cord-care clusters (52/4930). Neonatal mortality was 24% lower in the chlorhexidine group (relative risk 0.76 [95% CI 0.55-1.04]) than in the dry cord care group. In infants enrolled within the first 24 h, mortality was significantly reduced by 34% in the chlorhexidine group (0.66 [0.46-0.95]). Soap and water did not reduce infection or mortality risk. INTERPRETATION Recommendations for dry cord care should be reconsidered on the basis of these findings that early antisepsis with chlorhexidine of the umbilical cord reduces local cord infections and overall neonatal mortality.


The New England Journal of Medicine | 1995

The prevalence of blindness and visual impairment among nursing home residents in Baltimore

James M. Tielsch; Jonathan C. Javitt; Anne L. Coleman; Joanne Katz; Alfred Sommer

BACKGROUND Although the prevalence of blindness and visual impairment increases with age, most surveys of ocular disease do not include nursing home residents. METHODS We conducted a population-based prevalence survey of persons 40 years of age or older residing in nursing homes in the Baltimore area. Of 738 eligible subjects in 30 nursing homes, 499 (67.6 percent) participated in the study. They had their eyes examined and their visual acuity tested and were interviewed in detail. The nonparticipants were more likely to be older, to be white, and to have lower scores on the Mini-Mental State Examination. RESULTS The prevalence of bilateral blindness (visual acuity < or = 20/200) was 17.0 percent. The prevalence of visual impairment (< 20/40 but > 20/200) was 18.8 percent. The frequency of blindness increased from 15.2 percent among those under 60 years of age to 28.6 percent among those 90 or older. The age-adjusted prevalence of blindness was 50 percent higher among blacks than among whites (P < 0.01). As compared with the noninstitutionalized population from the same communities, the rate of blindness among nursing home residents was 13.1 times higher for blacks and 15.6 times higher for whites. Cataract was the leading cause of blindness, followed by corneal opacity, macular degeneration, and glaucoma. We judged that 20 percent of the functional blindness and 37 percent of the visual impairment could be remedied by adequate refractive correction. CONCLUSIONS Blindness and visual impairment are highly prevalent among nursing home residents. Much of this loss of vision could be treated or prevented with appropriate ophthalmologic care.

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James M. Tielsch

George Washington University

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Alfred Sommer

Johns Hopkins University

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Keith P. West

Johns Hopkins University

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