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1.
Ophthalmic Res ; 67(1): 435-447, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39004077

RESUMEN

INTRODUCTION: The aim of this study was to evaluate the progression of atrophy as determined by spectral-domain optical coherence tomography (SD-OCT) in patients with molecularly confirmed ABCA4-associated Stargardt disease type 1 (STGD1) over a 24-month period in a multicenter prospective cohort study. METHODS: SD-OCT images from 428 eyes of 236 patients were analyzed. Change of mean thickness (MT) and intact area were estimated after semiautomated segmentation for the following individual layers in the central subfield (CS), inner ring (IR), and outer ring (OR) of the ETDRS grid: retinal pigment epithelium (RPE), outer segments (OSs), inner segments (IS), outer nuclear layer (ONL) inner retina (IR), and total retina. RESULTS: Statistically significant decreases of all outer retinal layers (RPE, OS, IS, and ONL) could be observed over a 24-month period both in decline of mean retinal thickness and intact area (p < 0.0001, respectively), whereas the IR showed an increase of retinal thickness in the CS and IR and remained unchanged in the OR. CONCLUSIONS: Significant loss could be detected in outer retinal layers by SD-OCT over a 24-month period in patients with STGD1. Loss of thickness and/or intact area of such layers may serve as potential endpoints for clinical trials that aim to slow down the disease progression of STGD1.


Asunto(s)
Progresión de la Enfermedad , Degeneración Macular , Epitelio Pigmentado de la Retina , Enfermedad de Stargardt , Tomografía de Coherencia Óptica , Agudeza Visual , Humanos , Tomografía de Coherencia Óptica/métodos , Enfermedad de Stargardt/diagnóstico , Masculino , Estudios Prospectivos , Femenino , Adulto , Adulto Joven , Persona de Mediana Edad , Degeneración Macular/diagnóstico , Degeneración Macular/congénito , Epitelio Pigmentado de la Retina/patología , Epitelio Pigmentado de la Retina/diagnóstico por imagen , Adolescente , Estudios de Seguimiento , Retina/diagnóstico por imagen , Retina/patología , Niño
2.
Ophthalmology ; 130(8): 863-871, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36963570

RESUMEN

TOPIC: We provide global estimates of the prevalence of corneal blindness and vision impairment in adults 40 years of age and older and examine the burden by age, sex, and geographic region from 1984 through 2020. CLINICAL RELEVANCE: Corneal opacities (COs) are among the top 5 causes of blindness worldwide, yet the global prevalence, regional differences, and risk factors are unclear. METHODS: Abstracted data from the published literature and surveys were obtained from the Global Burden of Disease Vision Loss Expert Group. We supplemented this by an independent systematic literature search of several databases. Studies that provided CO vision impairment data based on population-based surveys for those 40 years of age or older were included, for a total of 244. For each of the 4 outcomes of blindness and moderate to severe vision impairment (MSVI) caused by trachomatous and nontrachomatous CO (NTCO), time trends and differences in prevalence by region, age, and sex were evaluated using a Poisson log-linear model with a generalized estimating equation method. Age-standardized estimates of global prevalence of blindness and MSVI were calculated using the 2015 United Nations standard populations. RESULTS: The global prevalence of blindness resulting from NTCO in those 40 years and older was 0.081% (95% confidence interval [CI], 0.049%-0.315%); that of MSVI was 0.130% (95% CI, 0.087%-0.372%). A significant increase with age was found (prevalence rate ratio, 2.15; 95% CI, 1.99-2.32). Latin America and Europe showed the lowest rates, with 2- to 8-fold higher rates of blindness or MSVI in other regions. The global prevalence of blindness resulting from trachomatous CO in those 50 years and older was 0.0094% (95% CI, 0%-0.0693%); that from MSVI was 0.012% (95% CI, 0%-0.0761%). Blindness resulting from trachomatous CO and MSVI increased with age and female sex, and rates were significantly higher in the African regions. A decrease in trachomatous blindness rates over time was found (prevalence rate ratio, 0.91; 95% CI, 0.86-0.96). DISCUSSION: An estimated 5.5 million people worldwide are bilaterally blind or have MSVI resulting from CO, with an additional 6.2 million unilaterally blind. Blindness resulting from trachomatous CO is declining over time, likely because of the massive scaleup of the global trachoma elimination program and overall socioeconomic development. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.


Asunto(s)
Opacidad de la Córnea , Tracoma , Personas con Daño Visual , Adulto , Humanos , Femenino , Ceguera/epidemiología , Ceguera/etiología , Trastornos de la Visión/etiología , Opacidad de la Córnea/epidemiología , Prevalencia
3.
J Med Internet Res ; 25: e41233, 2023 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-37023420

RESUMEN

BACKGROUND: As trachoma is eliminated, skilled field graders become less adept at correctly identifying active disease (trachomatous inflammation-follicular [TF]). Deciding if trachoma has been eliminated from a district or if treatment strategies need to be continued or reinstated is of critical public health importance. Telemedicine solutions require both connectivity, which can be poor in the resource-limited regions of the world in which trachoma occurs, and accurate grading of the images. OBJECTIVE: Our purpose was to develop and validate a cloud-based "virtual reading center" (VRC) model using crowdsourcing for image interpretation. METHODS: The Amazon Mechanical Turk (AMT) platform was used to recruit lay graders to interpret 2299 gradable images from a prior field trial of a smartphone-based camera system. Each image received 7 grades for US $0.05 per grade in this VRC. The resultant data set was divided into training and test sets to internally validate the VRC. In the training set, crowdsourcing scores were summed, and the optimal raw score cutoff was chosen to optimize kappa agreement and the resulting prevalence of TF. The best method was then applied to the test set, and the sensitivity, specificity, kappa, and TF prevalence were calculated. RESULTS: In this trial, over 16,000 grades were rendered in just over 60 minutes for US $1098 including AMT fees. After choosing an AMT raw score cut point to optimize kappa near the World Health Organization (WHO)-endorsed level of 0.7 (with a simulated 40% prevalence TF), crowdsourcing was 95% sensitive and 87% specific for TF in the training set with a kappa of 0.797. All 196 crowdsourced-positive images received a skilled overread to mimic a tiered reading center and specificity improved to 99%, while sensitivity remained above 78%. Kappa for the entire sample improved from 0.162 to 0.685 with overreads, and the skilled grader burden was reduced by over 80%. This tiered VRC model was then applied to the test set and produced a sensitivity of 99% and a specificity of 76% with a kappa of 0.775 in the entire set. The prevalence estimated by the VRC was 2.70% (95% CI 1.84%-3.80%) compared to the ground truth prevalence of 2.87% (95% CI 1.98%-4.01%). CONCLUSIONS: A VRC model using crowdsourcing as a first pass with skilled grading of positive images was able to identify TF rapidly and accurately in a low prevalence setting. The findings from this study support further validation of a VRC and crowdsourcing for image grading and estimation of trachoma prevalence from field-acquired images, although further prospective field testing is required to determine if diagnostic characteristics are acceptable in real-world surveys with a low prevalence of the disease.


Asunto(s)
Colaboración de las Masas , Telemedicina , Tracoma , Humanos , Colaboración de las Masas/métodos , Fotograbar/métodos , Prevalencia , Telemedicina/métodos , Tracoma/diagnóstico
4.
Br J Nutr ; 127(4): 503-512, 2022 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-33829984

RESUMEN

Diets varying in SFA and MUFA content can impact glycaemic control; however, whether underlying differences in genetic make-up can influence blood glucose responses to these dietary fatty acids is unknown. We examined the impact of dietary oils varying in SFA/MUFA content on changes in blood glucose levels (primary outcome) and whether these changes were modified by variants in the stearoyl-CoA desaturase (SCD) gene (secondary outcome). Obese men and women participating in the randomised, crossover, isoenergetic, controlled-feeding Canola Oil Multicenter Intervention Trial II consumed three dietary oils for 6 weeks, with washout periods of ˜6 weeks between each treatment. Diets studied included a high SFA/low MUFA Control oil (36·6 % SFA/28·2 % MUFA), a conventional canola oil (6·2 % SFA/63·1 % MUFA) and a high-oleic acid canola oil (5·8 % SFA/74·7 % MUFA). No differences in fasting blood glucose were observed following the consumption of the dietary oils. However, when stratified by SCD genotypes, significant SNP-by-treatment interactions on blood glucose response were found with additive models for rs1502593 (P = 0·01), rs3071 (P = 0·02) and rs522951 (P = 0·03). The interaction for rs3071 remained significant (P = 0·005) when analysed with a recessive model, where individuals carrying the CC genotype showed an increase (0·14 (sem 0·09) mmol/l) in blood glucose levels with the Control oil diet, but reductions in blood glucose with both MUFA oil diets. Individuals carrying the AA and AC genotypes experienced reductions in blood glucose in response to all three oils. These findings identify a potential new target for personalised nutrition approaches aimed at improving glycaemic control.


Asunto(s)
Grasas Insaturadas en la Dieta , Estearoil-CoA Desaturasa , Adulto , Glucemia , Grasas de la Dieta , Ácidos Grasos , Ácidos Grasos Monoinsaturados , Femenino , Glucosa , Humanos , Masculino , Obesidad/genética , Aceite de Brassica napus , Estearoil-CoA Desaturasa/genética
5.
BMC Geriatr ; 22(1): 101, 2022 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-35120451

RESUMEN

BACKGROUND: Unintentional falls among older adults are associated with an ensuing decline in physical activity. Our objective is to evaluate the associations between fall status and changes in excursions after a fall. METHODS: Prospective cohort study of older adults with glaucoma or suspected glaucoma who reported falls for 1 year and wore a GPS device for 1-week at the baseline and 1 year later. GPS data were quantified into average: daily excursions, daily time away from home, and time per excursion. Fall status was categorized as fallers, injurious fallers, recurrent fallers, and recurrent injurious fallers. Multivariable negative binomial regression and generalized estimating equations models were employed to evaluate relationship between excursion parameters and fall status. RESULTS: A total of 192 eligible participants were included in the analyses. Approximately half were males (50.5%) with a mean age of 70.1 years and one-fourth were Black (28.1%). There were no significant associations between fall status and end-of-study excursion parameters (p > 0.06 for all), and visual field damage did not modify these relationships (p > 0.07 for all). For instance, patients with multiple falls during a one-year study period did not demonstrate more daily excursions (incident rate ratio [IRR] = 1.16, 95% confidence interval [CI] = 0.85 to 1.57), longer time per excursion (IRR = 0.79, 95% CI =0.59 to 1.06), or more average daily time away (IRR = 1.05, 95% CI = 0.84 to 1.30) conducted at the end-of-the study. Excursion parameters at the final assessment were not significantly different from those at baseline (p > 0.09 for all) and the changes did not vary by fall status (p > 0.23 for all). CONCLUSIONS: Older adults with glaucoma did not modify their travel away from home after experiencing a fall. Additional research is necessary to understand how often maintenance of travel outside the home after a fall reflects proper compensation for greater fall risk or continued activity despite the risk of falling.


Asunto(s)
Accidentes por Caídas , Glaucoma , Accidentes por Caídas/prevención & control , Anciano , Ejercicio Físico , Glaucoma/diagnóstico , Glaucoma/epidemiología , Humanos , Estudios Longitudinales , Masculino , Estudios Prospectivos
6.
N Engl J Med ; 378(17): 1583-1592, 2018 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-29694816

RESUMEN

BACKGROUND: We hypothesized that mass distribution of a broad-spectrum antibiotic agent to preschool children would reduce mortality in areas of sub-Saharan Africa that are currently far from meeting the Sustainable Development Goals of the United Nations. METHODS: In this cluster-randomized trial, we assigned communities in Malawi, Niger, and Tanzania to four twice-yearly mass distributions of either oral azithromycin (approximately 20 mg per kilogram of body weight) or placebo. Children 1 to 59 months of age were identified in twice-yearly censuses and were offered participation in the trial. Vital status was determined at subsequent censuses. The primary outcome was aggregate all-cause mortality; country-specific rates were assessed in prespecified subgroup analyses. RESULTS: A total of 1533 communities underwent randomization, 190,238 children were identified in the census at baseline, and 323,302 person-years were monitored. The mean (±SD) azithromycin and placebo coverage over the four twice-yearly distributions was 90.4±10.4%. The overall annual mortality rate was 14.6 deaths per 1000 person-years in communities that received azithromycin (9.1 in Malawi, 22.5 in Niger, and 5.4 in Tanzania) and 16.5 deaths per 1000 person-years in communities that received placebo (9.6 in Malawi, 27.5 in Niger, and 5.5 in Tanzania). Mortality was 13.5% lower overall (95% confidence interval [CI], 6.7 to 19.8) in communities that received azithromycin than in communities that received placebo (P<0.001); the rate was 5.7% lower in Malawi (95% CI, -9.7 to 18.9), 18.1% lower in Niger (95% CI, 10.0 to 25.5), and 3.4% lower in Tanzania (95% CI, -21.2 to 23.0). Children in the age group of 1 to 5 months had the greatest effect from azithromycin (24.9% lower mortality than that with placebo; 95% CI, 10.6 to 37.0). Serious adverse events occurring within a week after administration of the trial drug or placebo were uncommon, and the rate did not differ significantly between the groups. Evaluation of selection for antibiotic resistance is ongoing. CONCLUSIONS: Among postneonatal, preschool children in sub-Saharan Africa, childhood mortality was lower in communities randomly assigned to mass distribution of azithromycin than in those assigned to placebo, with the largest effect seen in Niger. Any implementation of a policy of mass distribution would need to strongly consider the potential effect of such a strategy on antibiotic resistance. (Funded by the Bill and Melinda Gates Foundation; MORDOR ClinicalTrials.gov number, NCT02047981 .).


Asunto(s)
Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Mortalidad del Niño , Enfermedades Transmisibles/mortalidad , Administración Masiva de Medicamentos , Administración Oral , Mortalidad del Niño/tendencias , Preescolar , Control de Enfermedades Transmisibles , Farmacorresistencia Bacteriana , Femenino , Humanos , Lactante , Mortalidad Infantil/tendencias , Malaui/epidemiología , Masculino , Administración Masiva de Medicamentos/mortalidad , Niger/epidemiología , Salud Pública , Tanzanía/epidemiología
7.
Ophthalmology ; 128(1): 70-77, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32615202

RESUMEN

PURPOSE: To define and quantify patterns of objectively measured daily physical activity by level of visual field (VF) damage in glaucoma patients including: (1) activity fragmentation, a metric of health and physiologic decline, and (2) diurnal patterns of activity, a measure of rest and activity rhythms. DESIGN: Prospective cohort study. PARTICIPANTS: Older adults diagnosed with glaucoma or suspected glaucoma. METHODS: Degree of VF damage was defined by the average VF sensitivity within the integrated VF (IVF). Each participant wore a hip accelerometer for 1 week to measure daily minute-by-minute activity for 7 consecutive days. Activity fragmentation was calculated as the reciprocal of the average activity bout duration in minutes, with higher fragmentation indicating more transient, rather than sustained, activity. Multivariate linear regression was used to test for cross-sectional associations between VF damage and activity fragmentation. Multivariate linear mixed-effects models were used to assess the associations between VF damage and accumulation of activity across 6 3-hour intervals from 5 am to 11 pm. MAIN OUTCOME MEASURES: Activity fragmentation and amount of activity (steps) over the course of the day. RESULTS: Each 5-dB decrement in IVF sensitivity was associated with 16.3 fewer active minutes/day (P < 0.05) and 2% higher activity fragmentation (P < 0.05), but not with the number of active bouts per day (P = 0.30). In time-of-day analyses, lower IVF sensitivity was associated with fewer steps over the 11 am to 2 pm, 2 pm to 5 pm, and 5 pm to 8 pm periods (106.6, 93.1, and 89.2 fewer steps, respectively; P < 0.05 for all), but not over other periods. The activity midpoint (the time at which half of the daily activity is completed) did not vary across level of VF damage. CONCLUSIONS: At worse levels of VF damage, glaucoma patients demonstrate shorter, more fragmented bouts of physical activity throughout the day and lower activity levels during typical waking hours, reflecting low physiologic functioning. Further work is needed to establish the temporality of this association and whether glaucoma patients with such activity patterns are at a greater risk of adverse health outcomes associated with activity fragmentation.


Asunto(s)
Ejercicio Físico/fisiología , Glaucoma/fisiopatología , Calidad de Vida , Trastornos de la Visión/fisiopatología , Agudeza Visual , Campos Visuales/fisiología , Anciano , Estudios Transversales , Femenino , Glaucoma/complicaciones , Humanos , Masculino , Estudios Prospectivos , Encuestas y Cuestionarios , Trastornos de la Visión/etiología , Pruebas del Campo Visual
8.
Sensors (Basel) ; 21(10)2021 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-34068938

RESUMEN

Understanding periods of the year associated with higher risk for falling and less physical activity may guide fall prevention and activity promotion for older adults. We examined the relationship between weather and seasons on falls and physical activity in a three-year cohort of older adults with glaucoma. Participants recorded falls information via monthly calendars and participated in four one-week accelerometer trials (baseline and per study year). Across 240 participants, there were 406 falls recorded over 7569 person-months, of which 163 were injurious (40%). In separate multivariable regression models incorporating generalized estimating equations, temperature, precipitation, and seasons were not significantly associated with the odds of falling, average daily steps, or average daily active minutes. However, every 10 °C increase in average daily temperature was associated with 24% higher odds of a fall being injurious, as opposed to non-injurious (p = 0.04). The odds of an injurious fall occurring outdoors, as opposed to indoors, were greater with higher average temperatures (OR per 10 °C = 1.46, p = 0.03) and with the summer season (OR = 2.69 vs. winter, p = 0.03). Falls and physical activity should be understood as year-round issues for older adults, although the likelihood of injury and the location of fall-related injuries may change with warmer season and temperatures.


Asunto(s)
Accidentes por Caídas , Glaucoma , Accidentes por Caídas/prevención & control , Anciano , Estudios de Cohortes , Ejercicio Físico , Humanos , Estudios Prospectivos , Estaciones del Año , Tiempo (Meteorología)
9.
Clin Infect Dis ; 70(4): 574-580, 2020 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-30950493

RESUMEN

BACKGROUND: The mechanisms underlying the finding of reduced child mortality in communities with biannual treatment with azithromycin remain unclear. We determined if there was a difference in morbidity in a cohort of children aged 1-36 months, residing in communities randomized to biannual treatment of preschool-aged children with azithromycin or placebo. METHODS: Thirty villages in Kilosa, Tanzania, were randomly assigned to receive biannual treatment of all children aged 1-59 months with either azithromycin (20/mg/kg single dose) or placebo. Children who were aged 1-36 months and participated in the baseline survey were enrolled in this cohort study and followed prospectively for 2 years. Children were monitored every 6 months for signs and symptoms of diarrheal disease, acute respiratory illness, and anemia. Mixed-effects models that include age, time, treatment arm, and the interaction of treatment arm and time as independent predictors were used to evaluate differences between children by treatment assignment over time. RESULTS: There was no difference in rates of diarrhea, fever, or anemia by treatment arm at baseline and at all phases of follow-up. The decline over time in reported cough was statistically significant in the children residing in the azithromycin communities, but not in the placebo communities. Once adjusting for clustering and age, the difference in decline between the 2 treatment arms was not significant (P = .09). CONCLUSIONS: A beneficial effect of azithromycin treatment on morbidity outcomes was not evident at biannual surveys. CLINICAL TRIALS REGISTRATION: NCT02048007.


Asunto(s)
Azitromicina , Administración Masiva de Medicamentos , Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Niño , Preescolar , Estudios de Cohortes , Humanos , Lactante , Morbilidad , Prevalencia , Tanzanía/epidemiología
10.
PLoS Med ; 17(9): e1003285, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32931496

RESUMEN

BACKGROUND: Biannual azithromycin distribution has been shown to reduce child mortality as well as increase antimicrobial resistance. Targeting distributions to vulnerable subgroups such as malnourished children is one approach to reaching those at the highest risk of mortality while limiting selection for resistance. The objective of this analysis was to assess whether the effect of azithromycin on mortality differs by nutritional status. METHODS AND FINDINGS: A large simple trial randomized communities in Niger to receive biannual distributions of azithromycin or placebo to children 1-59 months old over a 2-year timeframe. In exploratory subgroup analyses, the effect of azithromycin distribution on child mortality was assessed for underweight subgroups using weight-for-age Z-score (WAZ) thresholds of -2 and -3. Modification of the effect of azithromycin on mortality by underweight status was examined on the additive and multiplicative scale. Between December 2014 and August 2017, 27,222 children 1-11 months of age from 593 communities had weight measured at their first study visit. Overall, the average age among included children was 4.7 months (interquartile range [IQR] 3-6), 49.5% were female, 23% had a WAZ < -2, and 10% had a WAZ < -3. This analysis included 523 deaths in communities assigned to azithromycin and 661 deaths in communities assigned to placebo. The mortality rate was lower in communities assigned to azithromycin than placebo overall, with larger reductions among children with lower WAZ: -12.6 deaths per 1,000 person-years (95% CI -18.5 to -6.9, P < 0.001) overall, -17.0 (95% CI -28.0 to -7.0, P = 0.001) among children with WAZ < -2, and -25.6 (95% CI -42.6 to -9.6, P = 0.003) among children with WAZ < -3. No statistically significant evidence of effect modification was demonstrated by WAZ subgroup on either the additive or multiplicative scale (WAZ < -2, additive: 95% CI -6.4 to 16.8, P = 0.34; WAZ < -2, multiplicative: 95% CI 0.8 to 1.4, P = 0.50, WAZ < -3, additive: 95% CI -2.2 to 31.1, P = 0.14; WAZ < -3, multiplicative: 95% CI 0.9 to 1.7, P = 0.26). The estimated number of deaths averted with azithromycin was 388 (95% CI 214 to 574) overall, 116 (95% CI 48 to 192) among children with WAZ < -2, and 76 (95% CI 27 to 127) among children with WAZ < -3. Limitations include the availability of a single weight measurement on only the youngest children and the lack of power to detect small effect sizes with this rare outcome. Despite the trial's large size, formal tests for effect modification did not reach statistical significance at the 95% confidence level. CONCLUSIONS: Although mortality rates were higher in the underweight subgroups, this study was unable to demonstrate that nutritional status modified the effect of biannual azithromycin distribution on mortality. Even if the effect were greater among underweight children, a nontargeted intervention would result in the greatest absolute number of deaths averted. TRIAL REGISTRATION: The MORDOR trial is registered at clinicaltrials.gov NCT02047981.


Asunto(s)
Azitromicina/uso terapéutico , Trastornos de la Nutrición del Niño/tratamiento farmacológico , Trastornos de la Nutrición del Niño/mortalidad , Antibacterianos/uso terapéutico , Peso Corporal , Mortalidad del Niño/tendencias , Preescolar , Femenino , Humanos , Lactante , Mortalidad Infantil/tendencias , Malaria/tratamiento farmacológico , Masculino , Administración Masiva de Medicamentos/métodos , Administración Masiva de Medicamentos/mortalidad , Niger/epidemiología , Estado Nutricional , Delgadez
11.
Bull World Health Organ ; 98(10): 698-705, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33177759

RESUMEN

A simplified grading system for trachoma was published by the World Health Organization (WHO) in 1987. Intended for use by non-specialist personnel working at community level, the system includes five signs, each of which can be present or absent in any eye: (i) trachomatous trichiasis; (ii) corneal opacity; (iii) trachomatous inflammation-follicular; (iv) trachomatous inflammation-intense; and (v) trachomatous scarring. Though neither perfectly sensitive nor perfectly specific for trachoma, these signs have been essential tools for identifying populations that need interventions to eliminate trachoma as a public health problem. In 2018, at WHO's 4th global scientific meeting on trachoma, the definition of one of the signs, trachomatous trichiasis, was amended to exclude trichiasis that affects only the lower eyelid. This paper presents the amended system, updates its presentation, offers notes on its use and identifies areas of ongoing debate.


En 1987, l'Organisation mondiale de la Santé a publié un système de codage simplifié du trachome. Destiné au personnel non qualifié travaillant au sein des communautés, il comporte cinq signes, chacun pouvant être présent ou absent dans l'un ou l'autre œil: (i) le trichiasis trachomateux; (ii) l'opacité cornéenne; (iii) l'inflammation trachomateuse ­ folliculaire; (iv) l'inflammation trachomateuse ­ intense; et enfin, (v) la cicatrice trachomateuse. Bien qu'ils ne soient ni parfaitement précis, ni totalement spécifiques au trachome, ces signes constituent des outils essentiels pour identifier les populations qui nécessitent une intervention afin d'éliminer le trachome en tant que problème de santé publique. En 2018, lors de la quatrième réunion scientifique mondiale sur le trachome, la définition de l'un des signes, le trichiasis trachomateux, a été modifiée pour exclure du système de codage le trichiasis qui n'affecte que la paupière inférieure. Ce document expose le nouveau système, actualise sa présentation, formule des remarques sur son utilisation et identifie les domaines qui font encore l'objet de débats.


En 1987, la Organización Mundial de la Salud (OMS) publicó un sistema de clasificación simplificado para el tracoma. Este sistema fue diseñado para que lo utilice el personal no especializado que trabaja a nivel comunitario e incluye cinco signos, cada uno de los cuales puede estar presente o ausente en los ojos: i) la triquiasis tracomatosa; ii) la opacidad corneal; iii) la inflamación tracomatosa-folicular; iv) la inflamación tracomatosa-intensa; y v) la cicatrización tracomatosa. Si bien no son perfectamente sensibles ni muy específicos del tracoma, estos signos han sido herramientas esenciales para identificar a las poblaciones que requieren intervenciones para eliminar el tracoma como problema de salud pública. En 2018, se modificó la definición de uno de los signos, la triquiasis tracomatosa, en la 4.ª Reunión Científica Mundial sobre el Tracoma de la OMS, para descartar la triquiasis que solo afecta al párpado inferior. En el presente documento se describe el sistema modificado, se actualiza su presentación, se ofrecen observaciones sobre su aplicación y se identifican los ámbitos de debate en curso.


Asunto(s)
Tracoma , Triquiasis , Estudios Transversales , Humanos , Estudios Longitudinales , Prevalencia , Tracoma/epidemiología , Triquiasis/epidemiología
12.
Public Health Nutr ; 23(3): 538-543, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31496465

RESUMEN

OBJECTIVE: In the present study, we aimed to compare anthropometric indicators as predictors of mortality in a community-based setting. DESIGN: We conducted a population-based longitudinal study nested in a cluster-randomized trial. We assessed weight, height and mid-upper arm circumference (MUAC) on children 12 months after the trial began and used the trial's annual census and monitoring visits to assess mortality over 2 years. SETTING: Niger. PARTICIPANTS: Children aged 6-60 months during the study. RESULTS: Of 1023 children included in the study at baseline, height-for-age Z-score, weight-for-age Z-score, weight-for-height Z-score and MUAC classified 777 (76·0 %), 630 (61·6 %), 131 (12·9 %) and eighty (7·8 %) children as moderately to severely malnourished, respectively. Over the 2-year study period, fifty-eight children (5·7 %) died. MUAC had the greatest AUC (0·68, 95 % CI 0·61, 0·75) and had the strongest association with mortality in this sample (hazard ratio = 2·21, 95 % CI 1·26, 3·89, P = 0·006). CONCLUSIONS: MUAC appears to be a better predictor of mortality than other anthropometric indicators in this community-based, high-malnutrition setting in Niger.


Asunto(s)
Antropometría , Brazo/anatomía & histología , Mortalidad del Niño , Desnutrición/mortalidad , Estatura , Peso Corporal , Niño , Preescolar , Femenino , Humanos , Lactante , Estudios Longitudinales , Masculino , Niger , Estudios Prospectivos
13.
Ophthalmic Physiol Opt ; 40(2): 66-74, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32017172

RESUMEN

PURPOSE: Trachoma, a chronic conjunctivitis that can result in vision loss from trichiasis, is targeted for global elimination by 2020. Several milestones in the long process towards elimination are noteworthy for the impact they have had on changing or accelerating progress. The purpose of this review is to describe the milestones and the impact they have had both for trachoma elimination and beyond. FINDINGS: Eight milestones are presented. They are discovery of the causative agent; development of a clinical grading scheme; establishment of the World Health Organization Alliance for the Global Elimination of Trachoma by 2020; setting targets that define elimination; building an evidence base for trichiasis surgery; azithromycin donation programme; use of the SAFE strategy (Surgery, Antibiotics, Facial cleanliness, and Environmental improvement); and The Global Trachoma Mapping Project. SUMMARY: These milestones have significantly pushed the progress towards elimination. Despite challenges to achieving the goal of elimination by 2020, there is continued commitment into the future to ensure that this preventable cause of blindness is no longer a threat.


Asunto(s)
Antibacterianos/uso terapéutico , Ceguera/etiología , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Tracoma/tratamiento farmacológico , Ceguera/epidemiología , Ceguera/prevención & control , Infecciones Bacterianas del Ojo/complicaciones , Salud Global , Humanos , Prevalencia , Tracoma/complicaciones , Organización Mundial de la Salud
14.
Clin Infect Dis ; 68(12): 2114-2116, 2019 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-30561577

RESUMEN

In a large community-randomized trial, biannual azithromycin distributions significantly reduced postneonatal childhood mortality in sub-Saharan African sites. Here, we present a prespecified secondary analysis showing that much of the protective effect was in the first 3 months postdistribution. Distributing more frequently than biannually could be considered if logistically feasible. Clinical Trials Registration. NCT02047981.


Asunto(s)
Antibacterianos/administración & dosificación , Azitromicina/administración & dosificación , Mortalidad del Niño , Tracoma/tratamiento farmacológico , Tracoma/mortalidad , Preescolar , Femenino , Humanos , Lactante , Mortalidad Infantil , Recién Nacido , Masculino , Administración Masiva de Medicamentos , Factores de Tiempo , Tracoma/epidemiología
15.
PLoS Med ; 16(6): e1002835, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31237871

RESUMEN

BACKGROUND: Mass azithromycin distributions have been shown to reduce mortality in preschool children, although the factors mediating this mortality reduction are not clear. This study was performed to determine whether mass distribution of azithromycin, which has modest antimalarial activity, reduces the community burden of malaria. METHODS AND FINDINGS: In a cluster-randomized trial conducted from 23 November 2014 until 31 July 2017, 30 rural communities in Niger were randomized to 2 years of biannual mass distributions of either azithromycin (20 mg/kg oral suspension) or placebo to children aged 1 to 59 months. Participants, field staff, and investigators were masked to treatment allocation. The primary malaria outcome was the community prevalence of parasitemia on thick blood smear, assessed in a random sample of children from each community at study visits 12 and 24 months after randomization. Analyses were performed in an intention-to-treat fashion. At the baseline visit, a total of 1,695 children were enumerated in the 15 azithromycin communities, and 3,029 children were enumerated in the 15 placebo communities. No communities were lost to follow-up. The mean prevalence of malaria parasitemia at baseline was 8.9% (95% CI 5.1%-15.7%; 52 of 552 children across all communities) in the azithromycin-treated group and 6.7% (95% CI 4.0%-12.6%; 36 of 542 children across all communities) in the placebo-treated group. In the prespecified primary analysis, parasitemia was lower in the azithromycin-treated group at month 12 (mean prevalence 8.8%, 95% CI 5.1%-14.3%; 51 of 551 children across all communities) and month 24 (mean 3.5%, 95% CI 1.9%-5.5%; 21 of 567 children across all communities) than it was in the placebo-treated group at month 12 (mean 15.3%, 95% CI 10.8%-20.6%; 81 of 548 children across all communities) and month 24 (mean 4.8%, 95% CI 3.3%-6.4%; 28 of 592 children across all communities) (P = 0.02). Communities treated with azithromycin had approximately half the odds of parasitemia compared to those treated with placebo (odds ratio [OR] 0.54, 95% CI 0.30 to 0.97). Parasite density was lower in the azithromycin group than the placebo group at 12 and 24 months (square root-transformed outcome; density estimates were 7,540 parasites/µl lower [95% CI -350 to -12,550 parasites/µl; P = 0.02] at a mean parasite density of 17,000, as was observed in the placebo arm). No significant difference in hemoglobin was observed between the 2 treatment groups at 12 and 24 months (mean 0.34 g/dL higher in the azithromycin arm, 95% CI -0.06 to 0.75 g/dL; P = 0.10). No serious adverse events were reported in either group, and among children aged 1 to 5 months, the most commonly reported nonserious adverse events (i.e., diarrhea, vomiting, and rash) were less common in the azithromycin-treated communities. Limitations of the trial include the timing of the treatments and monitoring visits, both of which took place before the peak malaria season, as well as the uncertain generalizability to areas with different malaria transmission dynamics. CONCLUSIONS: Mass azithromycin distributions were associated with a reduced prevalence of malaria parasitemia in this trial, suggesting one possible mechanism for the mortality benefit observed with this intervention. TRIAL REGISTRATION: The trial was registered on ClinicalTrials.gov (NCT02048007).


Asunto(s)
Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Malaria/prevención & control , Administración Masiva de Medicamentos/métodos , Parasitemia/prevención & control , Preescolar , Análisis por Conglomerados , Femenino , Humanos , Lactante , Malaria/diagnóstico , Malaria/epidemiología , Masculino , Niger/epidemiología , Parasitemia/diagnóstico , Parasitemia/epidemiología , Factores de Tiempo
16.
J Nutr ; 149(3): 471-478, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30773586

RESUMEN

BACKGROUND: Novel oils high in monounsaturated fatty acids (MUFAs) and low in saturated fatty acids (SFAs) are an alternative to partially hydrogenated oils high in trans-unsaturated fatty acids. There is widespread use of high-MUFA oils across the food industry; however, limited knowledge of their cardiovascular impact exists. OBJECTIVES: We investigated the effects of diets containing canola oil, high-oleic acid canola oil (HOCO), and a control oil blend (diet formulated to emulate a Western fat profile) on lipids, lipoproteins, and apolipoproteins (apos), as secondary outcomes of the trial. METHODS: In a multi-center, double-blind, randomized, 3-period crossover, controlled feeding trial, men (n = 44) and women (n = 75) with a mean age of 44 y, mean body mass index (BMI; in kg/m2) of 31.7, and an increased waist circumference plus ≥1 metabolic syndrome criteria consumed prepared, weight-maintenance diets containing canola oil [17.5% MUFAs, 9.2% polyunsaturated fatty acids (PUFAs), 6.6% SFAs], HOCO (19.1% MUFAs, 7.0% PUFAs, 6.4% SFAs), or control oil (10.5% MUFAs, 10.0% PUFAs, 12.3% SFAs) for 6 wk with ≥4-wk washouts. Fasting serum lipids were assessed at baseline and 6 wk. Diet effects were examined using a repeated measures mixed model. RESULTS: Compared with the control, canola and HOCO diets resulted in lower endpoint total cholesterol (TC; -4.2% and -3.4%; P < 0.0001), LDL cholesterol (-6.6% and -5.6%; P < 0.0001), apoB (-3.7% and -3.4%; P = 0.002), and non-HDL cholesterol (-4.5% and -4.0%; P = 0.001), with no differences between canola diets. The TC:HDL cholesterol and apoB:apoA1 ratios were lower after the HOCO diet than after the control diet (-3.7% and -3.4%, respectively). There were no diet effects on triglyceride, HDL cholesterol, or apoA1 concentrations. CONCLUSIONS: HOCO, with increased MUFAs at the expense of decreased PUFAs, elicited beneficial effects on lipids and lipoproteins comparable to conventional canola oil and consistent with reduced cardiovascular disease risk in adults with central adiposity. This trial was registered at www.clinicaltrials.gov as NCT02029833.


Asunto(s)
Dieta , Ácidos Grasos/administración & dosificación , Lípidos/sangre , Lipoproteínas/sangre , Ácido Oléico/química , Aceite de Brassica napus/farmacología , Adulto , Anciano , Aterosclerosis/prevención & control , Estudios Cruzados , Suplementos Dietéticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aceite de Brassica napus/química , Circunferencia de la Cintura , Adulto Joven
17.
J Nutr ; 149(10): 1749-1756, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31291447

RESUMEN

BACKGROUND: Different fatty acids (FAs) can vary in their obesogenic effect, and genetic makeup can contribute to fat deposition in response to dietary FA composition. However, the antiobesogenic effects of the interactions between dietary MUFAs and genetics have scarcely been tested in intervention studies. OBJECTIVE: We evaluated the overall (primary outcome) and genetically modulated (secondary outcome) response in body weight and fat mass to different levels of MUFA consumption. METHODS: In the Canola Oil Multicenter Intervention Trial II, a randomized, crossover, isocaloric, controlled-feeding multicenter trial, 44 men and 71 women with a mean age of 44 y and an increased waist circumference (men ∼108 cm and women ∼102 cm) consumed each of 3 oils for 6 wk, separated by four 12-wk washout periods. Oils included 2 high-MUFA oils-conventional canola and high-oleic canola (<7% SFAs, >65% MUFAs)-and 1 low-MUFA/high-SFA oil blend (40.2% SFAs, 22.0% MUFAs). Body fat was measured using DXA. Five candidate single-nucleotide polymorphisms (SNPs) were genotyped using qualitative PCR. Data were analyzed using a repeated measures mixed model. RESULTS: No significant differences were observed in adiposity measures following the consumption of either high-MUFA diet compared with the low-MUFA/high-SFA treatment. However, when stratified by genotype, 3 SNPs within lipoprotein lipase (LPL), adiponectin, and apoE genes influenced, separately, fat mass changes in response to treatment (n = 101). Mainly, the LPL rs13702-CC genotype was associated with lower visceral fat (high-MUFA: -216.2 ± 58.6 g; low-MUFA: 17.2 ± 81.1 g; P = 0.017) and android fat mass (high-MUFA: -267.3 ± 76.4 g; low-MUFA: -21.7 ± 102.2 g; P = 0.037) following average consumption of the 2 high-MUFA diets. CONCLUSIONS: Common variants in LPL, adiponectin, and apoE genes modulated body fat mass response to dietary MUFAs in an isocaloric diet in adults with abdominal obesity. These findings might eventually help in developing personalized dietary recommendations for weight control. The trial was registered at clinicaltrials.gov as NCT02029833 (https://www.clinicaltrials.gov/ct2/show/NCT02029833?cond=NCT02029833&rank=1).


Asunto(s)
Ácidos Grasos Monoinsaturados/administración & dosificación , Regulación de la Expresión Génica/fisiología , Metabolismo de los Lípidos/genética , Tejido Adiposo , Adulto , Estudios Cruzados , Grasas de la Dieta , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad Abdominal , Polimorfismo de Nucleótido Simple
18.
Malar J ; 18(1): 284, 2019 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-31443654

RESUMEN

BACKGROUND: The MORDOR study, a cluster randomized clinical trial, showed that single-dose azithromycin (20 mg/kg) administered biannually for 2 years to preschool children reduced mortality; a study was conducted to determine its effect on clinical symptomatic episodes of malaria as a potential mechanism for mortality benefit. METHODS: A randomized control trial (RCT) was conducted, whereby 30 randomly selected communities in Kilosa District, Tanzania were randomized to receive 6-monthly treatment of children ages 1-59 months with single-dose azithromycin (20 mg/kg) vs. placebo. A prospective cohort study was nested within the RCT: children, aged 1 to 35 months at baseline, were randomly selected in each community and evaluated at 6-monthly intervals for 2 years. At each visit, the children were assessed for recent or ongoing fever and anti-malarial treatment; a rapid diagnostic test (RDT) for malaria was performed. The two major outcomes of interest were prevalence of RDT positivity and clinical malaria. The latter was defined as RDT-positivity with fever at time of evaluation and/or reported fever in the 3 days prior to evaluation. Methods that account for correlations at community level and within individuals over time were used to evaluate associations. RESULTS: At baseline, the prevalence rates in the children in the azithromycin and placebo arms were 17.6% vs. 15.5% for RDT positivity (p = 0.76) and 6.1% vs. 4.3% (p = 0.56) for clinical malaria. There was a decline in both RDT-positivity and clinical malaria over time in both arms. The difference by treatment assignment was not significant for clinical malaria; it was significant for RDT-positivity with greater odds of decline in the placebo arm (p = 0.01). CONCLUSIONS: Lack of evidence for a significant difference in the prevalence of clinical malaria in children at any visit following treatment suggests that the effect of single-dose azithromycin on malaria is at best transient and limited in scope. Chance overrepresentation of non-seasonal transmission in the communities in the azithromycin arm may account for higher rates of RDT-positivity and less decline over time. Trial registration Clinicaltrials.gov NCT02047981.


Asunto(s)
Antimaláricos/administración & dosificación , Azitromicina/administración & dosificación , Malaria/prevención & control , Preescolar , Femenino , Humanos , Lactante , Malaria/epidemiología , Masculino , Prevalencia , Estudios Prospectivos , Tanzanía/epidemiología , Factores de Tiempo
19.
Malar J ; 18(1): 389, 2019 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-31796025

RESUMEN

BACKGROUND: Biannual mass azithromycin administration to preschool children reduces all-cause mortality, but the mechanism for the effect is not understood. Azithromycin has activity against malaria parasites, and malaria is a leading cause of child mortality in the Sahel. The effect of biannual versus annual azithromycin distribution for trachoma control on serological response to merozoite surface protein 1 (MSP-119), a surrogate for malaria incidence, was evaluated among children in Niger. METHODS: Markers of malaria exposure were measured in two arms of a factorial randomized controlled trial designed to evaluate targeted biannual azithromycin distribution to children under 12 years of age compared to annual azithromycin to the entire community for trachoma control (N = 12 communities per arm). Communities were treated for 36 months (6 versus 3 distributions). Dried blood spots were collected at 36 months among children ages 1-5 years, and MSP-119 antibody levels were assessed using a bead-based multiplex assay to measure malaria seroprevalence. RESULTS: Antibody results were available for 991 children. MSP-119 seropositivity was 62.7% in the biannual distribution arm compared to 68.7% in the annual arm (prevalence ratio 0.91, 95% CI 0.83 to 1.00). Mean semi-quantitative antibody levels were lower in the biannual distribution arm compared to the annual arm (mean difference - 0.39, 95% CI - 0.05 to - 0.72). CONCLUSIONS: Targeted biannual azithromycin distribution was associated with lower malaria seroprevalence compared to that in a population that received annual distribution. Trial Registration Clinicaltrials.gov NCT00792922.


Asunto(s)
Antimaláricos/uso terapéutico , Azitromicina/uso terapéutico , Malaria/tratamiento farmacológico , Administración Masiva de Medicamentos/estadística & datos numéricos , Preescolar , Femenino , Humanos , Lactante , Malaria/epidemiología , Masculino , Proteína 1 de Superficie de Merozoito/análisis , Niger/epidemiología , Prevalencia , Estudios Seroepidemiológicos , Factores de Tiempo
20.
Ophthalmic Res ; 61(1): 36-43, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29940588

RESUMEN

PURPOSE: To describe the study design and characteristics at first visit of participants in the longitudinal Scotopic Microperimetric Assessment of Rod Function in Stargardt Disease (SMART) study. METHODS: Scotopic microperimetry (sMP) was performed in one designated study eye in a subset of participants with molecularly proven ABCA4-associated Stargardt disease (STGD1) enrolled in a multicenter natural history study (ProgStar). Study visits were every 6 months over a period ranging from 6 to 24 months, and also included fundus autofluorescence (FAF). RESULTS: SMART enrolled 118 participants (118 eyes). At the first visit of SMART, the mean sensitivity in mesopic microperimetry was 11.48 (±5.05; range 0.00-19.88) dB and in sMP 11.25 (±5.26; 0-19.25) dB. For FAF, all eyes had a lesion of decreased autofluorescence (mean lesion size 3.62 [±3.48; 0.10-21.46] mm2), and a total of 76 eyes (65.5%) had a lesion of definitely decreased autofluorescence with a mean lesion size of 3.46 (±3.60; 0.21-21.46) mm2. CONCLUSIONS: Rod function is impaired in STGD1 and can be assessed by sMP. Testing rod function may serve as a potential outcome measure for future clinical treatment trials. This is evaluated in the SMART study.


Asunto(s)
Degeneración Macular/congénito , Visión Nocturna/fisiología , Células Fotorreceptoras Retinianas Bastones/fisiología , Campos Visuales/fisiología , Adulto , Anciano , Femenino , Humanos , Estudios Longitudinales , Degeneración Macular/fisiopatología , Masculino , Persona de Mediana Edad , Proyectos de Investigación , Enfermedad de Stargardt , Agudeza Visual/fisiología , Pruebas del Campo Visual , Adulto Joven
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