J. Katz

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

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

The epidemiology of ocular trauma in rural Nepal

Aims: To estimate the incidence of ocular injury in rural Nepal and identify details about these injuries that predict poor visual outcome. Methods: Reports of ocular trauma were collected from 1995 through 2000 from patients presenting to the only eye care clinic in Sarlahi district, Nepal. Patients were given a standard free eye examination and interviewed about the context of their injury. Follow up examination was performed 2–4 months after the initial injury. Results: 525 cases of incident ocular injury were reported, with a mean age of 28 years. Using census data, the incidence was 0.65 per 1000 males per year, and 0.38 per 1000 females per year. The most common types of injury were lacerating and blunt, with the majority occurring at home or in the fields. Upon presentation to the clinic, 26.4% of patients had a best corrected visual acuity worse than 20/60 in the injured eye, while 9.6% had visual acuity worse than 20/400. 82% were examined at follow up: 11.2% of patients had visual acuity worse than 20/60 and 4.6% had vision worse than 20/400. A poor visual outcome was associated with increased age, care sought at a site other than the eye clinic, and severe injury. 3% of patients were referred for further care at an eye hospital at the initial visit; 7% had sought additional care in the interim between visits, with this subset representing a more severe spectrum of injuries. Conclusions: The detrimental effects of delayed care or care outside of the specialty eye clinic may reflect geographic or economic barriers to care. For optimal visual outcomes, patients who are injured in a rural setting should recognise the injury and seek early care at a specialty eye care facility. Findings from our study suggest that trained non-ophthalmologists may be able to clinically manage many eye injuries encountered in a rural setting in the “developing” world, reducing the demand for acute services of ophthalmologists in remote locations of this highly agricultural country.

Utilisation of eye care services in rural south India: the Aravind Comprehensive Eye Survey

Aim: To determine utilisation of eye care services in a rural population of southern India aged 40 years or older. Methods: 5150 subjects aged 40 years and older selected through a random cluster sampling technique from three districts in southern India underwent detailed ocular examinations for vision impairment, blindness, and ocular morbidity. Information regarding previous use of eye care services was collected from this population through a questionnaire administered by trained social workers before ocular examinations. Results: 3476 (72.7%) of 5150 subjects examined required eye care examinations. 1827 (35.5%) people gave a history of previous eye examinations, primarily from a general hospital (n = 1073, 58.7%). Increasing age and education were associated with increased utilisation of eye care services. Among the 3323 people who had never sought eye care, 912 (27.4%) had felt the need to have an eye examination but did not do so. Only one third of individuals with vision impairment, cataracts, refractive errors, and glaucoma had previously utilised services. Conclusions: A large proportion of people in a rural population of southern India who require eye care are currently not utilising existing eye care services. Improved strategies to improve uptake of services is required to reduce the huge burden of vision impairment in India.

Risk factors for age related cataract in a rural population of southern India: the Aravind Comprehensive Eye Study

Aim: To determine risk factors for lens opacities and age related cataract in an older rural population of southern India. Methods: A cross sectional population based study of 5150 people aged 40 years and above from 50 clusters from three districts in southern India. The lens was graded and classified after dilation using LOCS III system at the slit lamp for cataract. Definite cataract was defined as nuclear opalescence ⩾3.0 and/or cortical cataract ⩾3.0 and/or PSC ⩾2.0. Results: Definite cataracts were found in 2449 (47.5%) of 5150 subjects and the prevalence of cataract increased with age. The age adjusted prevalence of cataract was significantly lower in males (p = 0.0002). Demographic risk factors—increasing age and illiteracy—were common for the three subtypes of cataract; females were more likely to have cortical cataracts and nuclear cataracts. Additionally, nuclear cataracts were associated with moderate smoking (OR:1.28, 95% CI:1.01 to 1.64), lean body mass indices (OR: 1.37, 95% CI: 1.17 to 1.59) and higher waist to hip ratios (OR: 0.67, 95% CI: 0.54 to 0.82); cortical cataracts with hypertension (OR: 1.39 95% CI:1.11 to 1.72), pseudoexfoliation (OR:1.53,95% CI:1.17 to 2.01), and moderate to heavy smoking; and posterior subcapsular cataracts with diabetes (OR:1.55, 95% CI:1.12 to 2.15), lean body mass (OR:1.32, 95% CI:1.11 to 1.57), and high waist to hip ratios (OR: 0.77, 95% CI: 0.62 to 0.94). Conclusions: Risk factors for age related cataract in this population do not appear to be different from those reported in other populations. Further studies are required to identify the reason for the high prevalence of age related cataract and to understand better the role of each risk factor for cataractogenesis in this population.

The relation between birth size and the results of refractive error and biometry measurements in children

Aim: To examine the association of birth parameters with biometry and refraction in Singapore Chinese schoolchildren. Methods: Chinese children aged 7–9 years (n = 1413) from three schools in Singapore were recruited. Birth parameter information on birth weight, head circumference, length at birth, and gestational age were obtained from standard hospital records. Cycloplegic autorefraction, keratometry and biometry measures (axial length, vitreous chamber depth, lens thickness, and anterior chamber depth) were obtained. Results: Across the normal birthweight range (2.0–4.9 kg), children with birth weights ⩾4.0 kg had longer axial lengths (adjusted mean 23.65 mm versus 23.16 mm), compared with children with birth weights <2.5 kg, after controlling for age, sex, school, height, parental myopia, and gestational age. For every 1 cm increment in head circumference at birth, the axial length was longer by 0.05 mm. For every 1 cm increment in birth length, the axial length was longer by 0.02 mm in multivariate analysis. Additional week increases in gestational age till 46 weeks resulted in axial lengths that were longer by 0.04 mm, controlling for age, sex, school, parental myopia, and height. Children with larger birth weights, head circumferences, birth lengths, or gestational ages had deeper vitreous chambers and larger corneal curvature radii; however, there were no significant associations with refraction. Conclusions: Children who were born heavier, had larger head sizes or lengths at birth, or who were born more mature had longer axial lengths, and deeper vitreous chambers; but there were no differences in refraction at ages 7–9 years, possibly because of the observed compensatory flattening of the cornea.

Prevalence and risk factors for trachoma in Sarlahi district, Nepal.

AIMS: To estimate the prevalence of trachoma in preschool children in Sarlahi district, Nepal, and to identify risk factors for the disease. METHODS: A stratified random sample of 40 wards was selected for participation in a trachoma survey. Within each ward, a systematic 20% sample of children 24-76 months of age was chosen to determine the presence and severity of trachoma using the World Health Organisation grading system. RESULTS: A total of 891 children were selected and 836 (93.8%) were examined for trachoma from December 1990 to March 1991. The prevalence of active trachoma was 23.6% (21.9% follicular and 1.7% intense inflammatory). Cicatricial trachoma was not seen in this age group. The prevalence of trachoma ranged from 0 to 50% across wards with certain communities at much higher risk for trachoma than others. Three year old children had the highest prevalence of follicular (25.5%) and intense inflammatory trachoma (4.3%). Males and females had similar prevalence rates. Wards without any tube wells were at higher risk than those with one or more tube wells. Lower rates of trachoma were seen in families who lived in cement houses, had fewer people per room, more servants, more household goods, animals, and land. Hence, less access to water, crowding and lower socioeconomic status were risk factors for trachoma. CONCLUSIONS: Although follicular trachoma is prevalent, intense inflammatory trachoma is relatively rare and scarring was not observed in this preschool population. Hence, this population may not be at high risk for repeat infections leading to blindness in adulthood.

Breast-feeding initiation time and neonatal mortality risk among newborns in South India

Objective:To examine the association between breast-feeding initiation time and neonatal mortality in India, where breast-feeding initiation varies widely from region to region.Study Design:Data were collected as part of a community-based, randomized, placebo-controlled trial of the impact of vitamin A supplementation in rural villages of Tamil Nadu, India. Multivariate binomial regression analysis was used to estimate the association between neonatal mortality and breast-feeding initiation time (<12 h, 12 to 24 h, >24 h) among infants surviving a minimum of 48 h.Result:Among 10 464 newborns, 82.1% were first breast-fed before 12 h, 13.8% were breast-fed between 12 and 24 h, and 4.1% were breast-fed after 24 h. After adjusting for birth weight, gestational age and other covariates, late initiators (>24 h) were at ∼78% higher risk of death (relative risk=1.78 (95% confidence interval (CI)=1.03 to 3.10)). There was no difference in mortality risk when comparing babies fed in the first 12 h compared with the second 12 h after birth.Conclusion:Late (>24 h) initiation of breast-feeding is associated with a higher risk of neonatal mortality in Tamil Nadu. Emphasis on breast-feeding promotion programs in low-resource settings of India where early initiation is low could significantly reduce neonatal mortality.

Supplementation with vitamin A early in life and subsequent risk of asthma

Animal models suggest that vitamin A deficiency affects lung development adversely and promotes airway hyperresponsiveness, and may predispose to an increased risk of asthma. We examined the long-term effects of vitamin A supplementation early in life on later asthma risk. In 2006–2008, we revisited participants from two cohorts in rural Nepal who were enrolled in randomised trials of vitamin A supplementation. The first cohort received vitamin A or placebo for <16 months during their pre-school years (1989–1991). The second cohort was born to mothers who received vitamin A, &bgr;-carotene or placebo before, during and after pregnancy (1994–1997). At follow-up, we asked about asthma symptoms and performed spirometry. Out of 6,421 subjects eligible to participate, 5,430 (85%) responded to our respiratory survey. Wheezing prevalence during the previous year was 4.8% in participants aged 9–13 yrs and 6.6% in participants aged 14–23 yrs. We found no differences between the vitamin A supplemented and placebo groups from either trial in the prevalence of lifetime or current asthma and wheeze or in spirometric indices of obstruction (p≥0.12 for all comparisons). Vitamin A supplementation early in life was not associated with a decreased risk of asthma in an area with chronic vitamin A deficiency.

Cigarette smoking during pregnancy in rural Nepal. Risk factors and effects of β -carotene and vitamin A supplementation

Objective: We examined risk factors of smoking and the association between smoking and pregnancy-related and 6-month infant mortality in rural Nepal, where 30% women reported smoking during pregnancy.Design: Cross-sectional analysis of risk factors associated with smoking status and health consequences of smoking, using prospective data collected as part of a randomized community trial to examine the effect of maternal vitamin A or β-carotene supplementation on maternal mortality.Setting: Rural, southeastern plains of Nepal.Subjects and methods: A total of 17 767 women contributed at least one pregnancy during 3.5 y of the study. Data on cigarette or bidi (rolled tobacco) smoking were collected using a 7-day recall, twice during pregnancy. Associations between smoking status and maternal diet, morbidity profile, household socioeconomic status and serum concentration of retinol, carotenoids and tocopherols were examined. Further, relative risk (RR) and 95% confidence intervals (CI) were calculated to estimate supplement effects on pregnancy-related mortality, stratified by smoking status during pregnancy.Results: Smokers were more likely to be older, illiterate and poor compared to nonsmokers. Fruit and vegetable consumption among smokers and nonsmokers did not vary. However, smokers were more likely to consume meat/fish/eggs and less likely to consume milk than nonsmokers. They were also more likely to report symptoms of vaginal bleeding, edema, severe headache and convulsions during pregnancy relative to nonsmokers. Mortality per 100 000 pregnancies appeared to be higher among smokers than nonsmokers in the placebo group (915 vs 584, RR=1.57, 95% CI: 0.80–3.08). β-Carotene supplementation reduced pregnancy-related mortality both among smokers (RR=0.31 95% CI: 0.11–0.89) and nonsmokers (RR=0.41, 95% CI: 0.19–0.89). Similar results obtained with vitamin A supplementation were not statistically significant. Infant mortality up to 6 months was ∼30% higher among smokers compared to nonsmokers in the placebo group both before and after adjusting for confounding factors. Neither supplement given to women reduced infant mortality.Conclusions: Cigarette smoking during pregnancy is associated with an increased risk of maternal and infant mortality in rural Nepal. β-Carotene and to some extent vitamin A may reduce the risk of pregnancy-related mortality, but not infant mortality, among both smokers and nonsmokers.

Changes in blindness prevalence over 16 years in Malawi: reduced prevalence but increased numbers of blind

Background/aims: In the coming two decades significant increases in the burden of blindness are anticipated unless concerted efforts are made to improve eye care in developing countries. Evidence of changing prevalence rates or numbers of blind people are few. The change in blindness prevalence and the number of blind people in an adult population of Malawi was measured over a 16 year period. Methods: In 1999 a population based survey of blindness in adults (age 50+) was conducted in Chikwawa district of Malawi. Visual acuity and cause of vision loss were recorded for each eye independently. Blindness was defined as presenting better eye vision of <6/60. Findings from a 1983 survey of blindness in the same district (using similar methods) were re-analysed to be comparable with the survey conducted in 1999. Results: Among 1630 enumerated adults 89% were examined. The age adjusted prevalence of blindness in the adult population was 5.4% and more common in women than men. In each age group the prevalence of blindness was lower in 1999 than in 1983; the overall reduction in blindness was 31%. During this period the 50+ population in Malawi increased almost twofold. Extrapolating the Chikwawa district data to the Malawi population reveals that the number of blind people has increased by 24%; the increase is primarily because of the large increase in the size of the most elderly group, aged 70 and above. Conclusion: The majority of blind people in Chikwawa (1983 and 1999) are in the age group 70 and over. This group has had the largest proportional increase in population size in this time. Services in this population have improved in the intervening 16 years and yet there was still an increase in the number of blind people. There was little change in excess blindness in women, suggesting that the same barriers that prevented utilisation of services in 1983 probably persist in 1999. Efforts to reach the most elderly and to reach women are needed to lead to a reduction in blind people in settings such as rural Malawi.