Risk factors for xerophthalmia in the Republic of Kiribati

Abstract

Objectives: To identify risk factors for xerophthalmia in the Republic of Kiribati.

Design: Case-control study.

Setting: The Republic of Kiribati.

Subjects: 666 xerophthalmic preschool children (cases) and 816 children without xerophthalmia (controls) from a population-based sample of 4619 children who participated in a xerophthalmia prevalence survey.

Main outcome measures: Clinical signs of xerophthalmia (night blindness, Bitot's spots, corneal xerophthalmia and keratomalacia).

Results: Multivariable logistic regression models showed older age [1.35(1.24, 1.47)] [odds ratio (95% confidence interval)]; male sex [1.32(1.05, 1.67)]; recent diarrhea [1.45(1.10, 1.89)]; severe [3.82(2.73, 5.35)], moderate [3.55(2.04, 6.18)], and mild [3.07(2.33, 4.04)] protein-energy malnutrition; current breast-feeding [0.30(0.19, 0.46)]; higher frequency of consumption of carotenoid-containing fruits and vegetables [0.93(0.80, 0.96)]; and the presence of a Foundation for the Peoples of the South Pacific garden project [0.70(0.52, 0.93)] were each independently associated with xerophthalmia. A recent history of measles was associated with corneal xerophthalmia [7.73(1.78, 33.65)].

Conclusions: These data provide further evidence of the relationship between xerophthalmia and factors that may be amenable to intervention, and suggest that greater availability and consumption of provitamin A carotenoids is associated with decreased risk of xerophthalmia among preschool children.

PIP: In 1989, in the Republic of Kiribati, two teams consisting of an ophthalmologist, a nurse, two field officers, and two village welfare group members conducted a population-based cross-sectional xerophthalmia survey among 4619 children aged 6-72 months living in the northern atolls of South Tarawa, Abaiang, and Butaritari and the southern atolls of Tabiteuea North, Nonouti, and Abemama. The study aimed to identify risk factors for xerophthalmia in Kiribati. Kiribati has among the highest xerophthalmia rates in the world. 666 children had xerophthalmia, while 816 children did not. The multivariable logistic regression (controlling for age and sex) revealed that significant independent risk factors for xerophthalmia were diarrhea (odds ratio [OR] = 1.45) and wasting (OR = 3.07 for mild wasting; OR = 3.55 for moderate wasting; OR = 3.82 for severe wasting). Factors associated with a protective effect against xerophthalmia included breast feeding (OR = 0.3), consumption of foods rich in vitamin A (OR = 0.93), and presence of a garden project of the Foundation for the Peoples of the South Pacific in the village (OR = 0.7). When the researchers controlled for age, sex, breast feeding status, diarrhea, protein-energy malnutrition, frequency of consumption of foods rich in vitamin A, and the presence of a village garden project, the association between measles and corneal xerophthalmia persisted (OR = 7.73). These findings suggest that greater availability and consumption of foods rich in vitamin A reduces the risk of xerophthalmia among preschool children.