All day-long pacifier use and intelligence quotient in childhood: A birth cohort study.

BACKGROUND: Literature on pacifier use remains controversial, but mostly suggests an inverse association with childhood intelligence. OBJECTIVES: The objective of this study was to assess the association between pacifier use and intelligence quotient (IQ) in six-year-old children from a birth cohort. METHODS: Data from 3532 children from the 2004 Pelotas (Brazil) Birth Cohort were analysed. Children were recruited and assessed at birth and followed up at 3 months, and 1, 2, 4, and 6 years. Data on pacifier use duration and intensity were obtained via interviews with mothers in all six follow-up visits. IQ was estimated at 6 years using the Wechsler Intelligence Scale for Children and standardised for the analyses. Crude and adjusted coefficients were calculated (linear regression) for all the data collected in follow-up assessments for pacifier use. RESULTS: IQ was inversely associated with all pacifier use indicators. Children who used a pacifier all day long (ADL) at any follow-up showed an IQ 0.18 (95% confidence interval [CI] 0.11, 0.24) standard deviations below those who never used it ADL, after adjusting for confounders. The strength of association increased with number of assessments reporting ADL pacifier use, from a reduction in IQ of 0.13 (95% CI 0.06, 0.21) to 0.34 (95% CI 0.15, 0.52) standard deviations for ADL use in one and in all four follow-up visits, respectively. CONCLUSIONS: We found a strong association between intense pacifier use up to 4 years of age and lower IQ at 6 years. A dose-response gradient was observed, with greater IQ deficits in children who used a ADL pacifier for longer durations. The mechanisms underlying this association need to be clarified. One hypothesis is that children using a pacifier, especially those who use it more intensely, are less stimulated.

Contextual and individual inequalities of multimorbidity in Brazilian adults: a cross-sectional national-based study.

OBJECTIVES: The study aims to evaluate the magnitude of multimorbidity in Brazilian adults, as well to measure their association with individual and contextual factors stratified by Brazilian states and regions. METHODS: A national-based cross-sectional study was carried out in 2013 with Brazilian adults. Multimorbidity was evaluated by a list of 22 physical and mental morbidities (based on self-reported medical diagnosis and Patient Health Questionnaire-9 for depression). The outcome was analysed taking ≥2 and ≥3 diseases as cut-off points. Factor analysis (FA) was used to identify disease patterns and multilevel models were used to test association with individual and contextual variables. RESULTS: The sample comprised 60 202 individuals. Multimorbidity frequency was 22.2% (95% CI 21.5 to 22.9) for ≥2 morbidities and 10.2% (95% CI 9.7 to 10.7) for ≥3 morbidities. In the multilevel adjusted models, females, older people, those living with a partner and having less schooling presented more multiple diseases. No linear association was found according to wealth index but greater outcome frequency was found in individuals with midrange wealth index. Living in states with higher levels of education and wealthier states was associated with greater multimorbidity. Two patterns of morbidities (cardiometabolic problems and respiratory/mental/muscle-skeletal disorders) explained 92% of total variance. The relationship of disease patterns with individual and contextual variables was similar to the overall multimorbidity, with differences among Brazilian regions. CONCLUSIONS: In Brazil, at least 19 million adults had multimorbidity. Frequency is similar to that found in other Low and and Middle Income Countries. Contextual and individual social inequalities were observed.