Interaction between mother’s age and schooling at birth on under-five mortality

Abstract

IntroductionPregnancy at age extremes and low maternal schooling are associated with under-five mortality. However, we found no study in the literature that evaluated the interaction between mother’s age and schooling on under-five mortality measured in both multiplicative and additive scales.
 Objectives and ApproachTo analyze the interaction between mother’s age and schooling on under-five mortality in a birth cohort in Rio de Janeiro City (Brazil) (N=153,527 live births). We carried out a non-concurrent cohort study using probabilistic record linkage of birth and death records for Rio de Janeiro (Brazil). The association between under-five mortality according to mother’s age (15-19, 20-34 and 35 years or more) and schooling (less than 4 years; 4 to 11 years and 12 or more years of schooling) were estimated using generalized linear models with binomial distribution and Neperian logarithm function. The interaction was evaluated in both scales.
 ResultsThe under-five mortality rate was 14.0 per thousand live births. Higher rates were observed among women with less than 4 years’ schooling and in age extremes. When compared with women aged 20 to 34 years and with more than 12 years’ schooling, these women had the following risk ratios: 15 to 19 years – RR = 3.66 (95% CI 2.39; 5.62); 35 years or more – RR = 2.74 (95% CI 1.83; 4.11). We did not observe statistically significant interactions in the additive and multiplicative scales.
 Conclusion/ImplicationsAlthough we did not observe an interaction between mother’s age and schooling, under-five mortality was more frequent among women with less the four years’ schooling, especially at the age extremes, suggests these are more vulnerable groups that demand greater attention in care.