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The Lancet. Global Health Feb 2021To contribute to the WHO initiative, VISION 2020: The Right to Sight, an assessment of global vision impairment in 2020 and temporal change is needed. We aimed to... (Meta-Analysis)
Meta-Analysis
BACKGROUND
To contribute to the WHO initiative, VISION 2020: The Right to Sight, an assessment of global vision impairment in 2020 and temporal change is needed. We aimed to extensively update estimates of global vision loss burden, presenting estimates for 2020, temporal change over three decades between 1990-2020, and forecasts for 2050.
METHODS
We did a systematic review and meta-analysis of population-based surveys of eye disease from January, 1980, to October, 2018. Only studies with samples representative of the population and with clearly defined visual acuity testing protocols were included. We fitted hierarchical models to estimate 2020 prevalence (with 95% uncertainty intervals [UIs]) of mild vision impairment (presenting visual acuity ≥6/18 and <6/12), moderate and severe vision impairment (<6/18 to 3/60), and blindness (<3/60 or less than 10° visual field around central fixation); and vision impairment from uncorrected presbyopia (presenting near vision
FINDINGS
In 2020, an estimated 43·3 million (95% UI 37·6-48·4) people were blind, of whom 23·9 million (55%; 20·8-26·8) were estimated to be female. We estimated 295 million (267-325) people to have moderate and severe vision impairment, of whom 163 million (55%; 147-179) were female; 258 million (233-285) to have mild vision impairment, of whom 142 million (55%; 128-157) were female; and 510 million (371-667) to have visual impairment from uncorrected presbyopia, of whom 280 million (55%; 205-365) were female. Globally, between 1990 and 2020, among adults aged 50 years or older, age-standardised prevalence of blindness decreased by 28·5% (-29·4 to -27·7) and prevalence of mild vision impairment decreased slightly (-0·3%, -0·8 to -0·2), whereas prevalence of moderate and severe vision impairment increased slightly (2·5%, 1·9 to 3·2; insufficient data were available to calculate this statistic for vision impairment from uncorrected presbyopia). In this period, the number of people who were blind increased by 50·6% (47·8 to 53·4) and the number with moderate and severe vision impairment increased by 91·7% (87·6 to 95·8). By 2050, we predict 61·0 million (52·9 to 69·3) people will be blind, 474 million (428 to 518) will have moderate and severe vision impairment, 360 million (322 to 400) will have mild vision impairment, and 866 million (629 to 1150) will have uncorrected presbyopia.
INTERPRETATION
Age-adjusted prevalence of blindness has reduced over the past three decades, yet due to population growth, progress is not keeping pace with needs. We face enormous challenges in avoiding vision impairment as the global population grows and ages.
FUNDING
Brien Holden Vision Institute, Fondation Thea, Fred Hollows Foundation, Bill & Melinda Gates Foundation, Lions Clubs International Foundation, Sightsavers International, and University of Heidelberg.
Topics: Aged; Aged, 80 and over; Blindness; Cataract; Eye Diseases; Female; Forecasting; Glaucoma; Global Burden of Disease; Global Health; Humans; Macular Degeneration; Male; Middle Aged; Presbyopia; Vision, Low; Visual Acuity
PubMed: 33275950
DOI: 10.1016/S2214-109X(20)30425-3 -
Cancer Jan 2023Antibody-drug conjugates (ADCs) have complex molecular structures and have been tested in numerous clinical trials. Therefore, understanding the mechanisms of their... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Antibody-drug conjugates (ADCs) have complex molecular structures and have been tested in numerous clinical trials. Therefore, understanding the mechanisms of their toxicity when applied in medical practice is of high importance.
METHODS
In a systematic review and meta-analysis of data gathered from different scientific databases (PubMed, Embase, Cochrane, and Web of Science) between January 1, 2000, and June 7, 2022, the authors applied a random-effects model with logit transformation and evaluated the heterogeneity between studies using I statistics. The primary outcome was the incidence and 95% confidence interval (CI) for all-grade and grade ≥3 treatment-related adverse events and differences between different drugs, molecular structures, and cancer types.
RESULTS
In total, 2511 records were identified that included 169 clinical trials involving 22,492 patients. The overall incidence of treatment-related adverse events was 91.2% (95% CI, 90.7%-91.7%; I = 95.9%) for all-grade adverse events and 46.1% (95% CI, 45.2%-47.0%; I = 96.3%) for grade ≥3 adverse events. The most common all-grade adverse events were lymphopenia (53.0%; 95% CI, 48.7%-57.3%), nausea (44.1%; 95% CI, 43.2%-44.9%), neutropenia (43.7%; 95% CI, 42.6%-44.9%), blurred vision (40.5%; 95% CI, 37.4%-43.6%), and peripheral neuropathy (39.6%; 95% CI, 38.2%-41.1%); and the most common grade ≥3 adverse events were neutropenia (31.2%; 95% CI, 30.2%-32.3%), hypoesthesia (23.3%; 95% CI, 10.6%-35.9%), thrombocytopenia (22.6%; 95% CI, 21.3%-23.9%), febrile neutropenia (21.2%; 95% CI, 19.3%-23.1%), and lymphopenia (21.0%; 95% CI, 18.2%-23.7%).
CONCLUSIONS
Different ADCs appear to affect various treatment-related adverse events and provide comprehensive data on treatment-related adverse events for ADCs. The current results provide an important reference for clinicians and patients on how to care for toxicities from ADCs in clinical practice.
LAY SUMMARY
Unique anticancer drugs called antibody-drug conjugates (ADCs) have made significant progress in oncology in recent years because of their great success, and they are rapidly being used in the clinic as well as in hundreds of ongoing trials exploring their further use. The occurrence of serious side effects (adverse events) related to the receipt of ADCs was studied using data from 169 clinical trials involving 22,492 patients to determine the treatment-related causes of higher toxicity and adverse events in patients who receive ADCs, because these data are crucial for informing physicians how to safely treat patients using ADCs. The results indicate that different ADCs appear to affect various adverse events related to their use, providing comprehensive data on these ADCs that provide an important reference for clinicians and patients on how to care for toxicities from ADCs in clinical practice.
Topics: Humans; Immunoconjugates; Antineoplastic Agents; Neoplasms; Neutropenia; Lymphopenia
PubMed: 36408673
DOI: 10.1002/cncr.34507 -
The Lancet. Global Health Sep 2017Global and regional prevalence estimates for blindness and vision impairment are important for the development of public health policies. We aimed to provide global... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Global and regional prevalence estimates for blindness and vision impairment are important for the development of public health policies. We aimed to provide global estimates, trends, and projections of global blindness and vision impairment.
METHODS
We did a systematic review and meta-analysis of population-based datasets relevant to global vision impairment and blindness that were published between 1980 and 2015. We fitted hierarchical models to estimate the prevalence (by age, country, and sex), in 2015, of mild visual impairment (presenting visual acuity worse than 6/12 to 6/18 inclusive), moderate to severe visual impairment (presenting visual acuity worse than 6/18 to 3/60 inclusive), blindness (presenting visual acuity worse than 3/60), and functional presbyopia (defined as presenting near vision worse than N6 or N8 at 40 cm when best-corrected distance visual acuity was better than 6/12).
FINDINGS
Globally, of the 7·33 billion people alive in 2015, an estimated 36·0 million (80% uncertainty interval [UI] 12·9-65·4) were blind (crude prevalence 0·48%; 80% UI 0·17-0·87; 56% female), 216·6 million (80% UI 98·5-359·1) people had moderate to severe visual impairment (2·95%, 80% UI 1·34-4·89; 55% female), and 188·5 million (80% UI 64·5-350·2) had mild visual impairment (2·57%, 80% UI 0·88-4·77; 54% female). Functional presbyopia affected an estimated 1094·7 million (80% UI 581·1-1686·5) people aged 35 years and older, with 666·7 million (80% UI 364·9-997·6) being aged 50 years or older. The estimated number of blind people increased by 17·6%, from 30·6 million (80% UI 9·9-57·3) in 1990 to 36·0 million (80% UI 12·9-65·4) in 2015. This change was attributable to three factors, namely an increase because of population growth (38·4%), population ageing after accounting for population growth (34·6%), and reduction in age-specific prevalence (-36·7%). The number of people with moderate and severe visual impairment also increased, from 159·9 million (80% UI 68·3-270·0) in 1990 to 216·6 million (80% UI 98·5-359·1) in 2015.
INTERPRETATION
There is an ongoing reduction in the age-standardised prevalence of blindness and visual impairment, yet the growth and ageing of the world's population is causing a substantial increase in number of people affected. These observations, plus a very large contribution from uncorrected presbyopia, highlight the need to scale up vision impairment alleviation efforts at all levels.
FUNDING
Brien Holden Vision Institute.
Topics: Blindness; Global Health; Humans; Prevalence; Vision Disorders; Visual Acuity
PubMed: 28779882
DOI: 10.1016/S2214-109X(17)30293-0 -
The Cochrane Database of Systematic... Mar 2023Acute bacterial conjunctivitis is an infection of the conjunctiva and is one of the most common ocular disorders in primary care. Antibiotics are generally prescribed on... (Review)
Review
BACKGROUND
Acute bacterial conjunctivitis is an infection of the conjunctiva and is one of the most common ocular disorders in primary care. Antibiotics are generally prescribed on the basis that they may speed recovery, reduce persistence, and prevent keratitis. However, many cases of acute bacterial conjunctivitis are self-limited, resolving without antibiotic therapy. This Cochrane Review was first published in The Cochrane Library in 1999, then updated in 2006, 2012, and 2022.
OBJECTIVES
To assess the benefits and side effects of antibiotic therapy in the management of acute bacterial conjunctivitis.
SEARCH METHODS
We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2022, Issue 5), MEDLINE (January 1950 to May 2022), Embase (January 1980 to May 2022), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.
CLINICALTRIALS
gov), and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases in May 2022. SELECTION CRITERIA: We included randomized controlled trials (RCTs) in which any form of antibiotic treatment, with or without steroid, had been compared with placebo/vehicle in the management of acute bacterial conjunctivitis. This included topical and systemic antibiotic treatments.
DATA COLLECTION AND ANALYSIS
Two authors independently reviewed the titles and abstracts of identified studies. We assessed the full text of all potentially relevant studies and determined the included RCTs, which were further assessed for risk of bias using Cochrane methodology. We performed data extraction in a standardized manner and conducted random-effects meta-analyses using RevMan Web.
MAIN RESULTS
We included 21 eligible RCTs, 10 of which were newly identified in this update. A total of 8805 participants were randomized. All treatments were topical in the form of drops or ointment. The trials were heterogeneous in terms of their eligibility criteria, the nature of the intervention (antibiotic drug class, which included fluoroquinolones [FQs] and non-FQs; dosage frequency; duration of treatment), the outcomes assessed and the time points of assessment. We judged one trial to be of high risk of bias, four as low risk of bias, and the others as raising some concerns. Based on intention-to-treat (ITT) population, antibiotics likely improved clinical cure (resolution of clinical symptoms or signs) by 26% (RR 1.26, 95% CI 1.09 to 1.46; 5 trials, 1474 participants; moderate certainty) as compared with placebo. Subgroup analysis showed no differences by antibiotic class (P = 0.67) or treatment duration (P = 0.60). In the placebo group, 55.5% (408/735) of participants had spontaneous clinical resolution by days 4 to 9 versus 68.2% (504/739) of participants treated with an antibiotic. Based on modified ITT population, in which participants were analyzed after randomization on the basis of positive microbiological culture, antibiotics likely increased microbiological cure (RR 1.53, 95% CI 1.34 to 1.74; 10 trials, 2827 participants) compared with placebo at the end of therapy; there were no subgroup differences by drug class (P = 0.60). No study evaluated the cost-effectiveness of antibiotic treatment. Patients receiving antibiotics had a lower risk of treatment incompletion than those in the placebo group (RR 0.64, 95% CI 0.52 to 0.78; 13 trials, 5573 participants; moderate certainty) and were 27% less likely to have persistent clinical infection (RR 0.73, 95% CI 0.65 to 0.81; 19 trials, 5280 participants; moderate certainty). There was no evidence of serious systemic side effects reported in either the antibiotic or placebo group (very low certainty). When compared with placebo, FQs (RR 0.70, 95% CI 0.54 to 0.90) but not non-FQs (RR 4.05, 95% CI 1.36 to 12.00) may result in fewer participants with ocular side effects. However, the estimated effects were of very low certainty.
AUTHORS' CONCLUSIONS
The findings of this update suggest that the use of topical antibiotics is associated with a modestly improved chance of resolution in comparison to the use of placebo. Since no evidence of serious side effects was reported, use of antibiotics may therefore be considered to achieve better clinical and microbiologic efficacy than placebo. Increasing the proportion of participants with clinical cure or increasing the speed of recovery or both are important for individual return to work or school, allowing people to regain quality of life. Future studies may examine antiseptic treatments with topical antibiotics for reasons of cost and growing antibiotic resistance.
Topics: Humans; Anti-Bacterial Agents; Conjunctivitis, Bacterial; Randomized Controlled Trials as Topic
PubMed: 36912752
DOI: 10.1002/14651858.CD001211.pub4 -
Ophthalmology Oct 2018Presbyopia prevalence and spectacle-correction coverage were estimated by systematic review and meta-analysis of epidemiologic evidence, then modeled to expand to... (Meta-Analysis)
Meta-Analysis
TOPIC
Presbyopia prevalence and spectacle-correction coverage were estimated by systematic review and meta-analysis of epidemiologic evidence, then modeled to expand to country, region, and global estimates.
CLINICAL RELEVANCE
Understanding presbyopia epidemiologic factors and correction coverage is critical to overcoming the burden of vision impairment (VI) from uncorrected presbyopia.
METHODS
We performed systematic reviews of presbyopia prevalence and spectacle-correction coverage. Accepted presbyopia prevalence data were gathered into 5-year age groups from 0 to 90 years or older and meta-analyzed within World Health Organization global burden of disease regions. We developed a model based on amplitude of accommodation adjusted for myopia rates to match the regionally meta-analyzed presbyopia prevalence. Presbyopia spectacle-correction coverage was analyzed against country-level variables from the year of data collection; variation in correction coverage was described best by a model based on the Human Development Index, Gini coefficient, and health expenditure, with adjustments for age and urbanization. We used the models to estimate presbyopia prevalence and spectacle-correction coverage in each age group in urban and rural areas of every country in the world, and combined with population data to estimate the number of people with near VI.
RESULTS
We estimate there were 1.8 billion people (prevalence, 25%; 95% confidence interval [CI], 1.7-2.0 billion [23%-27%]) globally with presbyopia in 2015, 826 million (95% CI, 686-960 million) of whom had near VI because they had no, or inadequate, vision correction. Global unmet need for presbyopia correction in 2015 is estimated to be 45% (95% CI, 41%-49%). People with presbyopia are more likely to have adequate optical correction if they live in an urban area of a more developed country with higher health expenditure and lower inequality.
CONCLUSIONS
There is a significant burden of VI from uncorrected presbyopia, with the greatest burden in rural areas of low-resource countries.
Topics: Eyeglasses; Global Health; Humans; Presbyopia; Prevalence; Vision Disorders; Visual Acuity; Visually Impaired Persons
PubMed: 29753495
DOI: 10.1016/j.ophtha.2018.04.013 -
The Journal of Headache and Pain May 2019Migraine aura (MA) is a common and disabling neurological condition, characterized by transient visual, and less frequently sensory and dysphasic aura disturbances. MA...
BACKGROUND
Migraine aura (MA) is a common and disabling neurological condition, characterized by transient visual, and less frequently sensory and dysphasic aura disturbances. MA is associated with an increased risk of cardiovascular disorders and is often clinically difficult to distinguish from other serious neurological disorders such as transient ischemic attacks and epilepsy. Optimal clinical classification of MA symptoms is important for more accurate diagnosis and improved understanding of the pathophysiology of MA through clinical studies.
MAIN BODY
A systematic review of previous prospective and retrospective systematic recordings of visual aura symptoms (VASs) was performed to provide an overview of the different types of visual phenomena occurring during MA and their respective frequencies in patients. We found 11 retrospective studies and three prospective studies systematically describing VASs. The number of different types of VASs reported by patients in the studies ranged from two to 23. The most common were flashes of bright light, "foggy" vision, zigzag lines, scotoma, small bright dots and 'like looking through heat waves or water'.
CONCLUSIONS
We created a comprehensive list of VAS types reported by migraine patients based on all currently available data from clinical studies, which can be used for testing and validation in future studies. We propose that, based on this work, an official list of VAS types should be developed, preferably within the context of the International Classification of Headache Disorders of the International Headache Society.
Topics: Adult; Epilepsy; Female; Hallucinations; Humans; Ischemic Attack, Transient; Male; Migraine with Aura; Prospective Studies; Retrospective Studies; Vision, Ocular
PubMed: 31146673
DOI: 10.1186/s10194-019-1008-x -
The Cochrane Database of Systematic... Dec 2020Convergence insufficiency is a common binocular vision disorder in which the eyes have a strong tendency to drift outward (exophoria) with difficulty turning the eyes... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Convergence insufficiency is a common binocular vision disorder in which the eyes have a strong tendency to drift outward (exophoria) with difficulty turning the eyes inward when reading or doing close work.
OBJECTIVES
To assess the comparative effectiveness and relative ranking of non-surgical interventions for convergence insufficiency through a systematic review and network meta-analysis (NMA).
SEARCH METHODS
We searched CENTRAL, MEDLINE, Embase, PubMed and three trials registers up to 20 September 2019.
SELECTION CRITERIA
We included randomized controlled trials (RCTs) examining any form of non-surgical intervention versus placebo, no treatment, sham treatment, or other non-surgical interventions. Participants were children and adults with symptomatic convergence insufficiency.
DATA COLLECTION AND ANALYSIS
We followed standard Cochrane methodology. We performed NMAs separately for children and adults.
MAIN RESULTS
We included 12 trials (six in children and six in adults) with a total of 1289 participants. Trials evaluated seven interventions: 1) office-based vergence/accommodative therapy with home reinforcement; 2) home-based pencil/target push-ups; 3) home-based computer vergence/accommodative therapy; 4) office-based vergence/accommodative therapy alone; 5) placebo vergence/accommodative therapy or other placebo intervention; 6) prism reading glasses; and 7) placebo reading glasses. Six RCTs in the pediatric population randomized 968 participants. Of these, the Convergence Insufficiency Treatment Trial (CITT) Investigator Group completed four RCTs with 737 participants. All four CITT RCTs were rated at low risk of bias. Diagnostic criteria and outcome measures were identical or similar among these trials. The four CITT RCTs contributed data to the pediatric NMA, incorporating interventions 1, 2, 3 and 5. When treatment success was defined by a composite outcome requiring both clinical measures of convergence to be normal, and also show a pre-specified magnitude of improvement, we found high-certainty evidence that office-based vergence/accommodative therapy with home reinforcement increases the chance of a successful outcome, compared with home-based computer vergence/accommodative therapy (risk ratio (RR) 1.96, 95% confidence interval (CI) 1.32 to 2.94), home-based pencil/target push-ups (RR 2.86, 95% CI 1.82 to 4.35); and placebo (RR 3.04, 95% CI 2.32 to 3.98). However, there may be no evidence of any treatment difference between home-based computer vergence/accommodative therapy and home-based pencil/target push-ups (RR 1.44, 95% CI 0.93 to 2.24; low-certainty evidence), or between either of the two home-based therapies and placebo therapy, for the outcome of treatment success. When treatment success was defined as the composite convergence and symptom success outcome, we found moderate-certainty evidence that participants who received office-based vergence/accommodative therapy with home reinforcement were 5.12 (95% CI 2.01 to 13.07) times more likely to achieve treatment success than those who received placebo therapy. We found low-certainty evidence that participants who received office-based vergence/accommodative therapy with home reinforcement might be 4.41 (95% CI 1.26 to 15.38) times more likely to achieve treatment success than those who received home-based pencil push-ups, and 4.65 (95% CI 1.23 to 17.54) times more likely than those who received home-based computer vergence/accommodative therapy. There was no evidence of any treatment difference between home-based pencil push-ups and home-based computer vergence/accommodative therapy, or between either of the two home-based therapies and placebo therapy. One RCT evaluated the effectiveness of base-in prism reading glasses in children. When base-in prism reading glasses were compared with placebo reading glasses, investigators found no evidence of a difference in the three outcome measures of near point convergence (NPC), positive fusional vergence (PFV), or symptom scores measured by the Convergence Insufficiency Symptom Survey (CISS). Six RCTs in the adult population randomized 321 participants. We rated only one RCT at low risk of bias. Because not all studies of adults included composite success data, we could not conduct NMAs for treatment success. We thus were limited to comparing the mean difference (MD) between interventions for improving NPC, PFV, and CISS scores individually using data from three RCTs (107 participants; interventions 1, 2, 4 and 5). Compared with placebo treatment, office-based vergence accommodative therapy was relatively more effective in improving PFV (MD 16.73, 95% CI 6.96 to 26.60), but there was no evidence of a difference for NPC or the CISS score. There was no evidence of difference for any other comparisons for any outcomes. One trial evaluated base-in prism glasses prescribed for near-work activities and found that the prism glasses group had fewer symptoms compared with the placebo glasses group at three months (MD -8.9, 95% CI -11.6 to -6.3). The trial found no evidence of a difference with this intervention in NPC or PFV. No adverse effects related to study treatments were reported for any of the included studies. Excellent adherence was reported for office-based vergence/accommodative therapy (96.6% or higher) in two trials. Reported adherence with home-based therapy was less consistent, with one study reporting decreasing adherence over time (weeks 7 to 12) and lower completion rates with home-based pencil/target push-ups.
AUTHORS' CONCLUSIONS
Current research suggests that office-based vergence/accommodative therapy with home reinforcement is more effective than home-based pencil/target push-ups or home-based computer vergence/accommodative therapy for children. In adults, evidence of the effectiveness of various non-surgical interventions is less clear.
Topics: Adult; Bias; Child; Exotropia; Eyeglasses; Humans; Network Meta-Analysis; Ocular Motility Disorders; Orthoptics; Randomized Controlled Trials as Topic
PubMed: 33263359
DOI: 10.1002/14651858.CD006768.pub3 -
BMJ Clinical Evidence Jun 2011Amblyopia is commonly associated with squint (strabismus) or refractive errors resulting in different visual inputs to each eye during the sensitive period of visual... (Review)
Review
INTRODUCTION
Amblyopia is commonly associated with squint (strabismus) or refractive errors resulting in different visual inputs to each eye during the sensitive period of visual development (<7-8 years of age). The cumulative incidence is estimated at 2% to 4% in children aged up to 15 years.
METHODS AND OUTCOMES
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to detect amblyopia early? What are the effects of medical treatments for amblyopia? We searched: Medline, Embase, The Cochrane Library, and other important databases up to May 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations, such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
RESULTS
We found 33 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
CONCLUSIONS
In this systematic review, we present information relating to the effectiveness and safety of the following interventions: active vision therapy; glasses alone or with occlusion; or penalisation to treat amblyopia; and screening to detect amblyopia early.
Topics: Amblyopia; Eyeglasses; Humans; Refractive Errors; Sensory Deprivation; Strabismus; Visual Acuity
PubMed: 21714945
DOI: No ID Found -
The Cochrane Database of Systematic... Mar 2022Vitamin A deficiency (VAD) is a major public health problem in low- and middle-income countries, affecting 190 million children under five years of age and leading to... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Vitamin A deficiency (VAD) is a major public health problem in low- and middle-income countries, affecting 190 million children under five years of age and leading to many adverse health consequences, including death. Based on prior evidence and a previous version of this review, the World Health Organization has continued to recommend vitamin A supplementation (VAS) for children aged 6 to 59 months. The last version of this review was published in 2017, and this is an updated version of that review.
OBJECTIVES
To assess the effects of vitamin A supplementation (VAS) for preventing morbidity and mortality in children aged six months to five years.
SEARCH METHODS
We searched CENTRAL, MEDLINE, Embase, six other databases, and two trials registers up to March 2021. We also checked reference lists and contacted relevant organisations and researchers to identify additional studies.
SELECTION CRITERIA
Randomised controlled trials (RCTs) and cluster-RCTs evaluating the effect of synthetic VAS in children aged six months to five years living in the community. We excluded studies involving children in hospital and children with disease or infection. We also excluded studies evaluating the effects of food fortification, consumption of vitamin A rich foods, or beta-carotene supplementation.
DATA COLLECTION AND ANALYSIS
For this update, two review authors independently assessed studies for inclusion resolving discrepancies by discussion. We performed meta-analyses for outcomes, including all-cause and cause-specific mortality, disease, vision, and side effects. We used the GRADE approach to assess the quality of the evidence.
MAIN RESULTS
The updated search identified no new RCTs. We identified 47 studies, involving approximately 1,223,856 children. Studies were set in 19 countries: 30 (63%) in Asia, 16 of these in India; 8 (17%) in Africa; 7 (15%) in Latin America, and 2 (4%) in Australia. About one-third of the studies were in urban/periurban settings, and half were in rural settings; the remaining studies did not clearly report settings. Most studies included equal numbers of girls and boys and lasted about one year. The mean age of the children was about 33 months. The included studies were at variable overall risk of bias; however, evidence for the primary outcome was at low risk of bias. A meta-analysis for all-cause mortality included 19 trials (1,202,382 children). At longest follow-up, there was a 12% observed reduction in the risk of all-cause mortality for VAS compared with control using a fixed-effect model (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.83 to 0.93; high-certainty evidence). Nine trials reported mortality due to diarrhoea and showed a 12% overall reduction for VAS (RR 0.88, 95% CI 0.79 to 0.98; 1,098,538 children; high-certainty evidence). There was no evidence of a difference for VAS on mortality due to measles (RR 0.88, 95% CI 0.69 to 1.11; 6 studies, 1,088,261 children; low-certainty evidence), respiratory disease (RR 0.98, 95% CI 0.86 to 1.12; 9 studies, 1,098,538 children; low-certainty evidence), and meningitis. VAS reduced the incidence of diarrhoea (RR 0.85, 95% CI 0.82 to 0.87; 15 studies, 77,946 children; low-certainty evidence), measles (RR 0.50, 95% CI 0.37 to 0.67; 6 studies, 19,566 children; moderate-certainty evidence), Bitot's spots (RR 0.42, 95% CI 0.33 to 0.53; 5 studies, 1,063,278 children; moderate-certainty evidence), night blindness (RR 0.32, 95% CI 0.21 to 0.50; 2 studies, 22,972 children; moderate-certainty evidence), and VAD (RR 0.71, 95% CI 0.65 to 0.78; 4 studies, 2262 children, moderate-certainty evidence). However, there was no evidence of a difference on incidence of respiratory disease (RR 0.99, 95% CI 0.92 to 1.06; 11 studies, 27,540 children; low-certainty evidence) or hospitalisations due to diarrhoea or pneumonia. There was an increased risk of vomiting within the first 48 hours of VAS (RR 1.97, 95% CI 1.44 to 2.69; 4 studies, 10,541 children; moderate-certainty evidence).
AUTHORS' CONCLUSIONS
This update identified no new eligible studies and the conclusions remain the same. VAS is associated with a clinically meaningful reduction in morbidity and mortality in children. Further placebo-controlled trials of VAS in children between six months and five years of age would not change the conclusions of this review, although studies that compare different doses and delivery mechanisms are needed. In populations with documented VAD, it would be unethical to conduct placebo-controlled trials.
Topics: Child; Child, Preschool; Diarrhea; Dietary Supplements; Female; Humans; Male; Measles; Morbidity; Respiration Disorders; Vitamin A; Vitamin A Deficiency
PubMed: 35294044
DOI: 10.1002/14651858.CD008524.pub4 -
BMJ Clinical Evidence Sep 2009Amblyopia is commonly associated with squint (strabismus) or refractive errors resulting in different visual inputs to each eye during the sensitive period of visual... (Review)
Review
INTRODUCTION
Amblyopia is commonly associated with squint (strabismus) or refractive errors resulting in different visual inputs to each eye during the sensitive period of visual development (<7-8 years of age). The cumulative incidence is estimated at 2% to 4% in children aged up to 15 years.
METHODS AND OUTCOMES
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to detect amblyopia early? What are the effects of medical treatments for amblyopia? We searched: Medline, Embase, The Cochrane Library, and other important databases up to May 2008 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations, such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
RESULTS
We found 16 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
CONCLUSIONS
In this systematic review, we present information relating to the effectiveness and safety of the following interventions: active vision therapy; glasses alone or with occlusion; or penalisation to treat amblyopia; and screening to detect amblyopia early.
Topics: Amblyopia; Eyeglasses; Humans; Mydriatics; Sensory Deprivation; Strabismus; Visual Acuity
PubMed: 21726480
DOI: No ID Found