Whole-body hypothermia for neonates with hypoxic-ischemic encephalopathy

BACKGROUND

Hypothermia is protective against brain injury after asphyxiation in animal models. However, the safety and effectiveness of hypothermia in term infants with encephalopathy is uncertain.

METHODS

We conducted a randomized trial of hypothermia in infants with a gestational age of at least 36 weeks who were admitted to the hospital at or before six hours of age with either severe acidosis or perinatal complications and resuscitation at birth and who had moderate or severe encephalopathy. Infants were randomly assigned to usual care (control group) or whole-body cooling to an esophageal temperature of 33.5 degrees C for 72 hours, followed by slow rewarming (hypothermia group). Neurodevelopmental outcome was assessed at 18 to 22 months of age. The primary outcome was a combined end point of death or moderate or severe disability.

RESULTS

Of 239 eligible infants, 102 were assigned to the hypothermia group and 106 to the control group. Adverse events were similar in the two groups during the 72 hours of cooling. Primary outcome data were available for 205 infants. Death or moderate or severe disability occurred in 45 of 102 infants (44 percent) in the hypothermia group and 64 of 103 infants (62 percent) in the control group (risk ratio, 0.72; 95 percent confidence interval, 0.54 to 0.95; P=0.01). Twenty-four infants (24 percent) in the hypothermia group and 38 (37 percent) in the control group died (risk ratio, 0.68; 95 percent confidence interval, 0.44 to 1.05; P=0.08). There was no increase in major disability among survivors; the rate of cerebral palsy was 15 of 77 (19 percent) in the hypothermia group as compared with 19 of 64 (30 percent) in the control group (risk ratio, 0.68; 95 percent confidence interval, 0.38 to 1.22; P=0.20).

CONCLUSIONS

Whole-body hypothermia reduces the risk of death or disability in infants with moderate or severe hypoxic-ischemic encephalopathy.

Causes of blindness and vision impairment in 2020 and trends over 30 years, and prevalence of avoidable blindness in relation to VISION 2020: the Right to Sight: an analysis for the Global Burden of Disease Study

BACKGROUND

Many causes of vision impairment can be prevented or treated. With an ageing global population, the demands for eye health services are increasing. We estimated the prevalence and relative contribution of avoidable causes of blindness and vision impairment globally from 1990 to 2020. We aimed to compare the results with the World Health Assembly Global Action Plan (WHA GAP) target of a 25% global reduction from 2010 to 2019 in avoidable vision impairment, defined as cataract and undercorrected refractive error.

METHODS

We did a systematic review and meta-analysis of population-based surveys of eye disease from January, 1980, to October, 2018. We fitted hierarchical models to estimate prevalence (with 95% uncertainty intervals [UIs]) of moderate and severe vision impairment (MSVI; presenting visual acuity from <6/18 to 3/60) and blindness (<3/60 or less than 10° visual field around central fixation) by cause, age, region, and year. Because of data sparsity at younger ages, our analysis focused on adults aged 50 years and older.

FINDINGS

Global crude prevalence of avoidable vision impairment and blindness in adults aged 50 years and older did not change between 2010 and 2019 (percentage change -0·2% [95% UI -1·5 to 1·0]; 2019 prevalence 9·58 cases per 1000 people [95% IU 8·51 to 10·8], 2010 prevalence 96·0 cases per 1000 people [86·0 to 107·0]). Age-standardised prevalence of avoidable blindness decreased by -15·4% [-16·8 to -14·3], while avoidable MSVI showed no change (0·5% [-0·8 to 1·6]). However, the number of cases increased for both avoidable blindness (10·8% [8·9 to 12·4]) and MSVI (31·5% [30·0 to 33·1]). The leading global causes of blindness in those aged 50 years and older in 2020 were cataract (15·2 million cases [9% IU 12·7-18·0]), followed by glaucoma (3·6 million cases [2·8-4·4]), undercorrected refractive error (2·3 million cases [1·8-2·8]), age-related macular degeneration (1·8 million cases [1·3-2·4]), and diabetic retinopathy (0·86 million cases [0·59-1·23]). Leading causes of MSVI were undercorrected refractive error (86·1 million cases [74·2-101·0]) and cataract (78·8 million cases [67·2-91·4]).

INTERPRETATION

Results suggest eye care services contributed to the observed reduction of age-standardised rates of avoidable blindness but not of MSVI, and that the target in an ageing global population was not reached.

FUNDING

Brien Holden Vision Institute, Fondation Théa, The Fred Hollows Foundation, Bill & Melinda Gates Foundation, Lions Clubs International Foundation, Sightsavers International, and University of Heidelberg.

Haematococcus astaxanthin: applications for human health and nutrition

The carotenoid pigment astaxanthin has important applications in the nutraceutical, cosmetics, food and feed industries. Haematococcus pluvialis is the richest source of natural astaxanthin and is now cultivated at industrial scale. Astaxanthin is a strong coloring agent and a potent antioxidant - its strong antioxidant activity points to its potential to target several health conditions. This article covers the antioxidant, UV-light protection, anti-inflammatory and other properties of astaxanthin and its possible role in many human health problems. The research reviewed supports the assumption that protecting body tissues from oxidative damage with daily ingestion of natural astaxanthin might be a practical and beneficial strategy in health management.

Verteporfin therapy of subfoveal choroidal neovascularization in age-related macular degeneration: two-year results of a randomized clinical trial including lesions with occult with no classic choroidal neovascularization--verteporfin in photodynamic therapy report 2

PURPOSE

To determine if photodynamic therapy with verteporfin (Visudyne; Novartis AG, Bülach, Switzerland), termed verteporfin therapy, can safely reduce the risk of vision loss compared with a placebo (with sham treatment) in patients with subfoveal choroidal neovascularization caused by age-related macular degeneration who were identified with a lesion composed of occult with no classic choroidal neovascularization, or with presumed early onset classic choroidal neovascularization with good visual acuity letter score.

METHODS

This was a double-masked, placebo-controlled (sham treatment), randomized, multicenter clinical trial involving 28 ophthalmology practices in Europe and North America. The study population was patients with age-related macular degeneration, with subfoveal choroidal neovascularization lesions measuring no greater than 5400 microm in greatest linear dimension with either 1) occult with no classic choroidal neovascularization, best-corrected visual acuity score of at least 50 (Snellen equivalent approximately 20/100), and evidence of hemorrhage or recent disease progression; or 2) evidence of classic choroidal neovascularization with a best-corrected visual acuity score of at least 70 (better than a Snellen equivalent of approximately 20/40); assigned randomly (2:1) to verteporfin therapy or placebo therapy. Verteporfin (6 mg per square meter of body surface area) or placebo (5% dextrose in water) was administered by means of intravenous infusion of 30 ml over 10 minutes. Fifteen minutes after the start of the infusion, a laser light at 689 nm delivered 50 J/cm(2) by application of an intensity of 600 mW/cm(2) over 83 seconds using a spot size with a diameter 1000 microm larger than the greatest linear dimension of the choroidal neovascularization lesion on the retina. At follow-up examinations every 3 months, retreatment with the same regimen was applied if angiography showed fluorescein leakage. The main outcome measure was at least moderate vision loss, that is, a loss of at least 15 letters (approximately 3 lines), adhering to an intent-to-treat analysis with the last observation carried forward to impute for missing data.

RESULTS

Two hundred ten (93%) and 193 (86%) of the 225 patients in the verteporfin group compared with 104 (91%) and 99 (87%) of the 114 patients in the placebo group completed the month 12 and 24 examinations, respectively. On average, verteporfin-treated patients received five treatments over the 24 months of follow-up. The primary outcome was similar for the verteporfin-treated and the placebo-treated eyes through the month 12 examination, although a number of secondary visual and angiographic outcomes significantly favored the verteporfin-treated group. Between the month 12 and 24 examinations, the treatment benefit grew so that by the month 24 examination, the verteporfin-treated eyes were less likely to have moderate or severe vision loss. Of the 225 verteporfin-treated patients, 121 (54%) compared with 76 (67%) of 114 placebo-treated patients lost at least 15 letters (P =.023). Likewise, 67 of the verteporfin-treated patients (30%) compared with 54 of the placebo-treated patients (47%) lost at least 30 letters (P =.001). Statistically significant results favoring verteporfin therapy at the month 24 examination were consistent between the total population and the subgroup of patients with a baseline lesion composition identified as occult choroidal neovascularization with no classic choroidal neovascularization. This subgroup included 166 of the 225 verteporfin-treated patients (74%) and 92 of the 114 placebo-treated patients (81%). In these patients, 91 of the verteporfin-treated group (55%) compared with 63 of the placebo-treated group (68%) lost at least 15 letters (P =.032), whereas 48 of the verteporfin-treated group (29%) and 43 of the placebo-treated group (47%) lost at least 30 letters (P =.004). Other secondary outcomes, including visual acuity letter score worse than 34 (approximate Snellen equivalent of 20/200 or worse), mean change in visual acuity letter score, development of classic choroidal neovascularization, progression of classic choroidal neovascularization and size of lesion, favored the verteporfin-treated group at both the month 12 and month 24 examination for both the entire study group and the subgroup of cases with occult with no classic choroidal neovascularization at baseline. Subgroup analyses of lesions composed of occult with no classic choroidal neovascularization at baseline suggested that the treatment benefit was greater for patients with either smaller lesions (4 disc areas or less) or lower levels of visual acuity (letter score less than 65, an approximate Snellen equivalent of 20/50(-1) or worse) at baseline. Prospectively planned multivariable analyses confirmed that these two baseline variables affected the magnitude of treatment benefit. (ABSTRACT TRUNCATED)

Rare earth nanoparticles prevent retinal degeneration induced by intracellular peroxides

Photoreceptor cells are incessantly bombarded with photons of light, which, along with the cells' high rate of oxygen metabolism, continuously exposes them to elevated levels of toxic reactive oxygen intermediates (ROIs). Vacancy-engineered mixed-valence-state cerium oxide nanoparticles (nanoceria particles) scavenge ROIs. Our data show that nanoceria particles prevent increases in the intracellular concentrations of ROIs in primary cell cultures of rat retina and, in vivo, prevent loss of vision due to light-induced degeneration of photoreceptor cells. These data indicate that the nanoceria particles may be effective in inhibiting the progression of ROI-induced cell death, which is thought to be involved in macular degeneration, retinitis pigmentosa and other blinding diseases, as well as the ROI-induced death of other cell types in diabetes, Alzheimer's disease, atherosclerosis, stroke and so on. The use of nanoceria particles as a direct therapy for multiple diseases represents a novel strategy and suggests that they may represent a unique platform technology.

Long-term effects of indomethacin prophylaxis in extremely-low-birth-weight infants

BACKGROUND

The prophylactic administration of indomethacin reduces the frequency of patent ductus arteriosus and severe intraventricular hemorrhage in very-low-birth-weight infants (those with birth weights below 1500 g). Whether prophylaxis with indomethacin confers any long-term benefits that outweigh the risks of drug-induced reductions in renal, intestinal, and cerebral blood flow is not known.

METHODS

Soon after they were born, we randomly assigned 1202 infants with birth weights of 500 to 999 g (extremely low birth weight) to receive either indomethacin (0.1 mg per kilogram of body weight) or placebo intravenously once daily for three days. The primary outcome was a composite of death, cerebral palsy, cognitive delay, deafness, and blindness at a corrected age of 18 months. Secondary long-term outcomes were hydrocephalus necessitating the placement of a shunt, seizure disorder, and microcephaly within the same time frame. Secondary short-term outcomes were patent ductus arteriosus, pulmonary hemorrhage, chronic lung disease, ultrasonographic evidence of intracranial abnormalities, necrotizing enterocolitis, and retinopathy.

RESULTS

Of the 574 infants with data on the primary outcome who were assigned to prophylaxis with indomethacin, 271 (47 percent) died or survived with impairments, as compared with 261 of the 569 infants (46 percent) assigned to placebo (odds ratio, 1.1; 95 percent confidence interval, 0.8 to 1.4; P=0.61). Indomethacin reduced the incidence of patent ductus arteriosus (24 percent vs. 50 percent in the placebo group; odds ratio, 0.3; P<0.001) and of severe periventricular and intraventricular hemorrhage (9 percent vs. 13 percent in the placebo group; odds ratio, 0.6; P=0.02). No other outcomes were altered by the prophylactic administration of indomethacin.

CONCLUSIONS

In extremely-low-birth-weight infants, prophylaxis with indomethacin does not improve the rate of survival without neurosensory impairment at 18 months, despite the fact that it reduces the frequency of patent ductus arteriosus and severe periventricular and intraventricular hemorrhage.

The global impact of eye injuries

Using data compiled from the ophthalmic literature and WHO's Blindness Data Bank, the available information on eye injuries from an epidemiological and public health perspective has been extensively reviewed. This collection of data has allowed an analysis of risk factors, incidence, prevalence, and impact of eye injuries in terms of visual outcome. However, most of the estimates are based on information from More Developed Countries (MDCs). The severity of eye injuries can be assessed through proxy indicators such as: (i) potentially blinding bilateral injuries; (ii) open-globe injuries; (iii) endophthalmitis; (iv) enucleation or (v) defined visual impairment. Major risk factors for ocular injuries include age, gender, socioeconomic status and lifestyle. The site where the injury occurs is also related to a risk situation. Available information indicates a very significant impact of eye injuries in terms of medical care, needs for vocational rehabilitation and great socioeconomic costs. The global pattern of eye injuries and their consequences emerging from the present review, undertaken for planning purposes in the WHO Programme for the Prevention of Blindness, suggests that: some 55 million eye injuries restricting activities more than one day occur each year; 750,000 cases will require hospitalization each year, including some 200,000 open-globe injuries; there are approximately 1.6 million blind from injuries, an additional 2.3 million people with bilateral low vision from this cause, and almost 19 million with unilateral blindness or low vision. Further epidemiological studies are needed to permit more accurate planning of prevention and management measures; a standardized international template for reporting on eye injuries might be useful to this effect, along the lines of the reporting occurring through the US Eye Injury Registry.

Controlled trial of aspirin in cerebral ischemia

Adouble-blind trial of aspirin for the treatment of cerebral ischemia was begun in 1972 and continued for 37 months. This was accomplished despite difficulties in controlling a long-term study of a drug which has widespread availability and consumption. The study design, criteria for selection of patients, follow-up surveillance, and methods of data analysis are presented. We report only subjects without carotid surgery before randomization. Patients (178) who had carotid transient ischemic attacks (TIAs) were randomly allocated to aspirin or placebo and followed to determine the incidence of subsequent TIAs,death, cerebral infarction or retinal infarction. Analysis of the first six months of follow-up revealed a statistically significant differential in favar of aspirin when death or cerebral or retinal infarction and the occurrence of TIAs were grouped and considered together as end points. Significance in favor of aspirin treatment was mainly revealed in patients with a history of multiple TIAs and was most evident in those individuals having carotid lesions appropriate to the TIA symptoms. It cannot be inferred from this study that aspirin prevents stroke because when end points were restriced to death or cerebral or retinal infarction, there was no statistically significant differential between the aspirin and placebo treatments.

Zinc: role in immunity, oxidative stress and chronic inflammation

PURPOSE OF REVIEW

Zinc is essential for multiple cellular functions including immunity. Many investigators have used zinc supplementation in an attempt to affect the outcome of various diseases. These efforts were aimed at either supporting immunity by zinc administration or correcting the zinc dependent immune functions in zinc deficient individuals.

RECENT FINDINGS

In this review, recent findings of zinc supplementation in various diseases have been presented. Beneficial therapeutic response of zinc supplementation has been observed in the diarrhea of children, chronic hepatitis C, shigellosis, leprosy, tuberculosis, pneumonia, acute lower respiratory tract infection, common cold, and leishmaniasis. Zinc supplementation was effective in decreasing incidences of infections in the elderly, in patients with sickle cell disease (SCD) and decreasing incidences of respiratory tract infections in children. Zinc supplementation has prevented blindness in 25% of the elderly individuals with dry type of AMD. Zinc supplementation was effective in decreasing oxidative stress and generation of inflammatory cytokines such as TNF-alpha and IL-1beta in elderly individuals and patients with SCD.

SUMMARY

Zinc supplementation has been successfully used as a therapeutic and preventive agent for many conditions. Zinc functions as an intracellular signal molecule for immune cells.

Herpes simplex epithelial and stromal keratitis: an epidemiologic update

Herpes simplex virus (HSV) is associated with a variety of ocular diseases, including epithelial and stromal keratitis. HSV can cause stromal opacification and is believed to be the leading cause of infectious blindness in the developed world. An improved understanding of the global burden of HSV keratitis, including the incidence of severe vision loss, could have a significant effect on prevention and treatment and place it in perspective among causes of corneal ulceration. We found that the global incidence of HSV keratitis is roughly 1.5 million, including 40,000 new cases of severe monocular visual impairment or blindness each year. We also discuss relevant epidemiologic issues regarding HSV epithelial and stromal disease.

Effects of targeting higher vs lower arterial oxygen saturations on death or disability in extremely preterm infants: a randomized clinical trial

IMPORTANCE

The goal of oxygen therapy is to deliver sufficient oxygen to the tissues while minimizing oxygen toxicity and oxidative stress. It remains uncertain what values of arterial oxygen saturations achieve this balance in preterm infants.

OBJECTIVE

To compare the effects of targeting lower or higher arterial oxygen saturations on the rate of death or disability in extremely preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, double-blind trial in 25 hospitals in Canada, the United States, Argentina, Finland, Germany, and Israel in which 1201 infants with gestational ages of 23 weeks 0 days through 27 weeks 6 days were enrolled within 24 hours after birth between December 2006 and August 2010. Follow-up assessments began in October 2008 and ended in August 2012.

INTERVENTIONS

Study participants were monitored until postmenstrual ages of 36 to 40 weeks with pulse oximeters that displayed saturations of either 3% above or below the true values. Caregivers adjusted the concentration of oxygen to achieve saturations between 88% and 92%, which produced 2 treatment groups with true target saturations of 85% to 89% (n = 602) or 91% to 95% (n = 599). Alarms were triggered when displayed saturations decreased to 86% or increased to 94%.

MAIN OUTCOMES AND MEASURES

The primary outcome was a composite of death, gross motor disability, cognitive or language delay, severe hearing loss, or bilateral blindness at a corrected age of 18 months. Secondary outcomes included retinopathy of prematurity and brain injury.

RESULTS

Of the 578 infants with adequate data for the primary outcome who were assigned to the lower target range, 298 (51.6%) died or survived with disability compared with 283 of the 569 infants (49.7%) assigned to the higher target range (odds ratio adjusted for center, 1.08; 95% CI, 0.85 to 1.37; P = .52). The rates of death were 16.6% for those in the 85% to 89% group and 15.3% for those in the 91% to 95% group (adjusted odds ratio, 1.11; 95% CI, 0.80 to 1.54; P = .54). Targeting lower saturations reduced the postmenstrual age at last use of oxygen therapy (adjusted mean difference, -0.8 weeks; 95% CI, -1.5 to -0.1; P = .03) but did not alter any other outcomes.

CONCLUSION AND RELEVANCE

In extremely preterm infants, targeting oxygen saturations of 85% to 89% compared with 91% to 95% had no significant effect on the rate of death or disability at 18 months. These results may help determine the optimal target oxygen saturation.

TRIAL REGISTRATIONS

ISRCTN Identifier: 62491227; ClinicalTrials.gov Identifier: NCT00637169.

Low-dose aspirin and prevention of cranial ischemic complications in giant cell arteritis

OBJECTIVE

Cranial ischemic complications such as cerebrovascular accidents (CVAs) and acute visual loss are among the leading causes of giant cell arteritis (GCA)-related morbidity. In this retrospective study, we evaluated the effect of treatment with low-dose aspirin on the incidence of cranial ischemic complications in GCA.

METHODS

Charts of 175 consecutive patients in whom GCA was diagnosed between 1980 and 2000 were reviewed for medical data. Data for 166 patients who were followed up for at least 3 months were also available.

RESULTS

At the time of the diagnosis of GCA, 36 patients (21%) had already been receiving low-dose aspirin (100 mg/day). In all cases, the indication for this treatment was ischemic heart disease. There were no significant differences between the aspirin-treated and non-aspirin-treated groups regarding the mean age of patients, the male-to-female ratio, duration of GCA-related symptoms, rates of headaches, systemic symptoms, and jaw claudication, and the mean erythrocyte sedimentation rate, hemoglobin count, and platelet count. Cerebrovascular risk factors (hypertension, hyperlipidemia, or diabetes mellitus) were more common in the aspirin-treated group (38.9% versus 20%; P= 0.03). Cranial ischemic complications were diagnosed in 43 patients at presentation: 30 patients had acute visual loss, 11 had CVAs, and 2 had both conditions simultaneously. Only 3 of the aspirin-treated patients (8%) presented with cranial ischemic complications, compared with 40 (29%) of the non-aspirin-treated patients (P = 0.01). Despite the use of steroid therapy, cranial ischemic complications developed in 14 of the 166 patients followed up for 3 months or longer. However, cranial ischemic complications developed in only 3% of the aspirin-treated patients, compared with 13% of the patients treated with prednisone only (P = 0.02).

CONCLUSION

These data suggest that low-dose aspirin decreases the rate of visual loss and CVAs in patients with GCA.

Preventive eye care in people with diabetes is cost-saving to the federal government. Implications for health-care reform

OBJECTIVE

Diabetic retinopathy, which leads to macular edema and retinal neovascularization, is the leading cause of blindness among working-age Americans. Previous research has demonstrated significant cost savings associated with detection of eye disease in Americans with type I diabetes. However, detection and treatment of eye disease among those with type II diabetes was previously thought not to be cost-saving. Our purpose was to estimate the current and potential federal savings resulting from the screening and treatment of retinopathy in patients with type II diabetes, based on recently available data concerning efficacy of treating both macular edema and neovascularization along with new data on federal budgetary costs of blindness.

RESEARCH DESIGN AND METHODS

We used computer modeling, incorporating data from population-based epidemiological studies and multicenter clinical trials. Monte Carlo simulation was used, combined with sensitivity analysis and present value analysis of cost savings.

RESULTS

Screening and treatment for eye disease in patients with type II diabetes generates annual savings of $247.9 million to the federal budget and 53,986 person-years of sight, even at current suboptimal (60%) levels of care. If all patients with type II diabetes receive recommended care, the predicted net savings (discounted at 5%) exceeds $472.1 million and 94,304 person-years of sight. Nearly all savings are associated with detection and treatment of diabetic macular edema. Enrolling each additional person with type II diabetes into currently recommended ophthalmological care results in an average net savings of $975/person, even if all costs of care are borne by the federal government.

CONCLUSIONS

Our analysis indicates that prevention programs aimed at improving eye care for patients with diabetes not only reduce needless vision loss but also will provide a financial return on the investment of public funds.

Survival without disability to age 5 years after neonatal caffeine therapy for apnea of prematurity

CONTEXT

Very preterm infants are prone to apnea and have an increased risk of death or disability. Caffeine therapy for apnea of prematurity reduces the rates of cerebral palsy and cognitive delay at 18 months of age.

OBJECTIVE

To determine whether neonatal caffeine therapy has lasting benefits or newly apparent risks at early school age.

DESIGN, SETTING, AND PARTICIPANTS

Five-year follow-up from 2005 to 2011 in 31 of 35 academic hospitals in Canada, Australia, Europe, and Israel, where 1932 of 2006 participants (96.3%) had been enrolled in the randomized, placebo-controlled Caffeine for Apnea of Prematurity trial between 1999 and 2004. A total of 1640 children (84.9%) with birth weights of 500 to 1250 g had adequate data for the main outcome at 5 years.

MAIN OUTCOME MEASURES

Combined outcome of death or survival to 5 years with 1 or more of motor impairment (defined as a Gross Motor Function Classification System level of 3 to 5), cognitive impairment (defined as a Full Scale IQ<70), behavior problems, poor general health, deafness, and blindness.

RESULTS

The combined outcome of death or disability was not significantly different for the 833 children assigned to caffeine from that for the 807 children assigned to placebo (21.1% vs 24.8%; odds ratio adjusted for center, 0.82; 95% CI, 0.65-1.03; P = .09). The rates of death, motor impairment, behavior problems, poor general health, deafness, and blindness did not differ significantly between the 2 groups. The incidence of cognitive impairment was lower at 5 years than at 18 months and similar in the 2 groups (4.9% vs 5.1%; odds ratio adjusted for center, 0.97; 95% CI, 0.61-1.55; P = .89).

CONCLUSION

Neonatal caffeine therapy was no longer associated with a significantly improved rate of survival without disability in children with very low birth weights who were assessed at 5 years.

Model of complications of NIDDM. II. Analysis of the health benefits and cost-effectiveness of treating NIDDM with the goal of normoglycemia

OBJECTIVE

To analyze the health benefits and economics of treating NIDDM with the goal of normoglycemia.

RESEARCH DESIGN AND METHODS

Incidence-based simulation model of NIDDM was used. Hazard rates for complications were adjusted for glycemia using risk gradients from the Diabetes Control and Complications Trial. Treatment costs were estimated from national survey data and clinical trials. Incremental costs and benefits were expressed in present value dollars (3% discount rate). Life-years were adjusted for quality of life, yielding quality-adjusted life-years (QALYs).

RESULTS

Comprehensive treatment of NIDDM that maintains an HbA1c value of 7.2% is predicted to reduce the cumulative incidence of blindness, end-stage renal disease, and lower-extremity amputation by 72, 87, and 67%, respectively. Cardiovascular disease risk increased by 3% (no effect of treating glycemia is assumed). Life expectancy increased 1.39 years. The cost of treating hyperglycemia increased by almost twofold, which is partially offset by reductions in the cost of complications. The estimated incremental cost/QALY gained is $16,002. Treatment is more cost-effective for those with longer glycemic exposure (earlier onset of diabetes), minorities, and those with higher HbA1c under standard care.

CONCLUSIONS

The incremental effectiveness of treating NIDDM with the goal of normoglycemia is estimated to be approximately $16,000/QALY gained, which is in the range of interventions that are generally considered cost-effective.

The impact of Vision 2020 on global blindness

INTRODUCTION

Recent data suggest that there are 37 million blind people and 124 million with low vision, excluding those with uncorrected refractive errors. The main causes of global blindness are cataract, glaucoma, corneal scarring (from a variety of causes), age-related macular degeneration, and diabetic retinopathy.

CONCLUSION

It would appear that the global Vision 2020 initiative is having an impact to reduce avoidable blindness particularly from ocular infections, but more needs to be done to address cataract, glaucoma, and diabetic retinopathy.

Patterns of adherence to diabetes vision care guidelines: baseline findings from the Diabetic Retinopathy Awareness Program

OBJECTIVES

(1) To describe baseline patterns of adherence to American Diabetes Association and American Academy of Ophthalmology vision care guidelines for diabetes in the Diabetic Retinopathy Awareness Program, and (2) to evaluate factors associated with nonadherence. This paper describes the baseline characteristics of a population enrolled in a prospective, randomized clinical trial.

DESIGN

Cross-sectional study.

PARTICIPANTS

Between October 1993 and May 1994, the study identified 2308 persons with diabetes, 18 years of age or older, who were residents of Suffolk County, New York, via a multimedia community-wide recruitment campaign.

INTERVENTION AND METHODS

Eligibility for the trial was determined during a 20-minute phone interview, which included questions about vision care practices; diabetes management; and knowledge, attitudes, and beliefs about diabetes, vision, and diabetic retinopathy. This paper describes these patient characteristics at baseline. Eligible patients would be randomized subsequently to a 2-year diabetes educational intervention arm, which included mailed packets and newsletters focused on vision care, or to a control nonintervention arm.

MAIN OUTCOME MEASURE

Nonadherence to guidelines at baseline was defined as the absence of a dilated eye examination during the year before recruitment into the study.

RESULTS

Of the 2308 persons interviewed, 813 (35%) did not follow the vision care guidelines; two thirds of this group reported no eye examination in the year before the interview, and one third had an undilated examination. Ophthalmologists performed 49% of the examinations in the nonadherent group, versus 86% in the adherent group. In logistic regression analyses, factors related to nonadherence were: younger age (odds ratio [OR] = 0.97), type 2 diabetes with or without insulin use (OR = 1.62 and 1.99, respectively), shorter diabetes duration (OR = 0.97), last eye examination performed by an optometrist (OR = 5.32) or other nonophthalmologist (OR = 4.29), less practical knowledge about diabetes (OR = 1.57), and no prior formal diabetes education (OR = 1.30).

CONCLUSIONS

Within this population, more than one third of participants had not been following vision care guidelines. Nonadherence was linked to several potentially modifiable factors; changes in these factors could enhance the early detection of diabetic retinopathy.

Screening and prevention of diabetic blindness

Diabetic eye disease remains a major cause of blindness in the world. Laser treatment for proliferative diabetic retinopathy and diabetic macular edema became available more than two decades ago. The outcome of treatment depends on the timing of laser treatment. The laser treatment is optimally delivered when high-risk characteristics have developed in proliferative retinopathy or diabetic macular edema and before this has significantly affected vision. Laser treatment is usually successful if applied during this optimal period whereas the treatment benefit falls sharply if the treatment is applied too late. In order to optimize the timing of laser treatment in diabetic eye disease screening programs have been established. The oldest screening program is 20 years old and several programs have been established during the last decade. In this paper the organisation and methods of screening programs are described including direct and photographic screening. The incidence and prevalence of blindness is much lower in populations where screening for diabetic eye disease has been established compared to diabetic populations without screening. Technical advantages may allow increased efficiency and telescreening. From a public health standpoint screening for diabetic eye disease is one of the most cost effective health procedures available. Diabetic eye disease can be prevented using existing technology and the cost involved is many times less than the cost of diabetic blindness.

Changes in neurodevelopmental outcomes at 18 to 22 months' corrected age among infants of less than 25 weeks' gestational age born in 1993-1999

BACKGROUND

Increased survival rates for extremely preterm, extremely low birth weight infants during the postsurfactant era have been reported, but data on changes in neurosensory and developmental impairments are sparse.

OBJECTIVE

To compare neuromotor and neurodevelopmental outcomes at 18 to 22 months' corrected age for infants of <25 weeks' estimated gestational age (EGA) who were born in the 1990s.

METHODS

This was a multicenter, retrospective, comparative analysis of infants of <25 weeks' EGA, with birth weights of 501 to 1000 g, born between January 1993 and June 1996 (epoch I) or between July 1996 and December 1999 (epoch II), in the National Institute of Child Health and Human Development Neonatal Research Network. Neurodevelopmental assessments were performed at 18 to 22 months' corrected age. Logistic-regression models were constructed to evaluate the independent risk of cerebral palsy, Mental Development Index of <70, Psychomotor Development Index of <70, and neurodevelopmental impairment.

RESULTS

A total of 366 patients in epoch I and 473 patients in epoch II were evaluated. Prenatal steroid use, cesarean section, surfactant treatment, bronchopulmonary dysplasia, and severe retinopathy of prematurity were more likely in epoch II, whereas Apgar scores of <5 at 5 minutes, patent ductus arteriosus, and severe intraventricular hemorrhage were more likely in epoch I. The prevalences of cerebral palsy, Psychomotor Development Index of <70, and neurodevelopmental impairment were similar between epochs. The prevalences of Mental Development Index of <70 were 40% for epoch I and 47% for epoch II. Regression analysis revealed that epoch II was an independent risk factor for Mental Developmental Index of <70 (epoch I versus II: odds ratio: 0.63; 95% confidence interval: 0.45-0.87) but not for other outcomes.

CONCLUSIONS

Early childhood neurodevelopmental outcomes among infants of <25 weeks' EGA are not improving in the postsurfactant era, despite more aggressive perinatal and neonatal treatment. Later childhood follow-up assessment is needed to delineate trends in severe cognitive impairment in this extremely high-risk group.

Risk, causes, and outcomes of visual impairment after loss of vision in the non-amblyopic eye: a population-based study

BACKGROUND

Screening for amblyopia in early childhood is done in many countries to ensure that affected children are detected and treated within the critical period, and achieve a level of vision in their amblyopic eye that would be useful should they lose vision in their non-amblyopic eye later in life. We aimed to investigate the risk, causes, and outcomes of visual impairment attributable to loss of vision in the non-amblyopic eye.

METHODS

For 24 months from July, 1997, national surveillance was done to identify all individuals in the UK with unilateral amblyopia (acuity worse than 6/12) who had newly acquired vision loss in the non-amblyopic eye, resulting in acuity of worse than 6/12 or visual-field restriction precluding driving. Information about participants was obtained at presentation and 1 year later. Participants were categorised as having socially significant visual impairment, or visual impairment, severe visual impairment, or blindness, in accordance with WHO taxonomy.

FINDINGS

Of 370 eligible individuals, at presentation 104 (28%) had socially significant visual impairment, 180 (49%) visual impairment, and 86 (23%) severe visual impairment or blindness. The minimum risk of permanent visual impairment by age 95 years was 32.9 (95% CI 29.1-36.9) per 100,000 total population. The projected lifetime risk of vision loss for an individual with amblyopia was at least 1.2% (95% CI 1.1-1.4). Only 36 (35%) of 102 people previously in paid employment were able to continue.

INTERPRETATION

In the UK, where screening for amblyopia is under review, risk of serious vision loss affecting the non-amblyopic eye and its results are greater than that previously assumed. Thus, in addition to the benefits of improved vision in the amblyopic eye, treatment of amblyopia during childhood is a potentially valuable strategy to prevent incapacitating vision loss later in life.

Azathioprine in Behcet's syndrome: effects on long-term prognosis

OBJECTIVE

To assess the effect of azathioprine (AZA) treatment on long-term prognosis in Behçet's syndrome.

METHODS

Patients (all male) who took part in a double-blind, placebo-controlled trial of AZA a mean +/- SD of 94 +/- 10 months previously were reevaluated.

RESULTS

The emergence of blindness (log rank chi2 = 5.6, P = 0.02) and a 2-line drop in the visual acuity of the right eye (log rank chi2 = 5.9, P = 0.015) occurred significantly more frequently among the patients originally allocated to the placebo group compared with patients who originally received AZA, despite posttrial treatment for patients in both groups when needed. There was also a trend toward more frequent occurrence of extraocular complications in the placebo group. The beneficial effect of AZA was especially pronounced among patients who had eye involvement of short duration prior to their entry into the trial.

CONCLUSION

Early treatment with AZA tends to favorably affect the long-term prognosis of Behçet's syndrome.

Glaucoma

In 2000 an estimated 66.8 million people worldwide will have glaucoma, 6.7 million of whom will be bilaterally blind from irreversible optic-nerve damage. Yet even in developed countries with public educational programmes that target glaucoma, half of the individuals with glaucoma remain undiagnosed. Patients with even mild visual impairment secondary to glaucoma may have difficulties with mobility, driving, and social interactions. Although glaucoma may be associated with increased eye pressures, its diagnosis does not rely on a specific level of eye pressure. Diagnosis of glaucoma often relies on examination of the optic disc and assessment of the visual field. The two most common types of glaucoma--primary open-angle glaucoma and primary angle-closure glaucoma--have different risk factors. Although similar medications can be used to treat these two types of glaucoma, the overall management of patients differs in important ways. Until recently, there were no randomised clinical trials that showed the effectiveness of lowering eye pressures with medications or surgery in patients with glaucoma. However, in 1998 a randomised clinical trial showed the benefit of lowering eye pressure in patients with glaucoma who had eye pressures of 24 mm Hg or less. Because glaucoma is treatable, and because the visual impairment from glaucoma is irreversible, early detection of the disease is critically important.

Global cost of correcting vision impairment from uncorrected refractive error

OBJECTIVE

To estimate the global cost of establishing and operating the educational and refractive care facilities required to provide care to all individuals who currently have vision impairment resulting from uncorrected refractive error (URE).

METHODS

The global cost of correcting URE was estimated using data on the population, the prevalence of URE and the number of existing refractive care practitioners in individual countries, the cost of establishing and operating educational programmes for practitioners and the cost of establishing and operating refractive care facilities. The assumptions made ensured that costs were not underestimated and an upper limit to the costs was derived using the most expensive extreme for each assumption.

FINDINGS

There were an estimated 158 million cases of distance vision impairment and 544 million cases of near vision impairment caused by URE worldwide in 2007. Approximately 47 000 additional full-time functional clinical refractionists and 18 000 ophthalmic dispensers would be required to provide refractive care services for these individuals. The global cost of educating the additional personnel and of establishing, maintaining and operating the refractive care facilities needed was estimated to be around 20 000 million United States dollars (US$) and the upper-limit cost was US$ 28 000 million. The estimated loss in global gross domestic product due to distance vision impairment caused by URE was US$ 202 000 million annually.

CONCLUSION

The cost of establishing and operating the educational and refractive care facilities required to deal with vision impairment resulting from URE was a small proportion of the global loss in productivity associated with that vision impairment.