ABC | Volume 115, Nº2, August 2020

Original Article Jesus et al. Meta-analysis: body adiposity and apolipoproteins Arq Bras Cardiol. 2020; 115(2):163-171 High concentrations of ApoB and LDL are associated with atherosclerosis and stroke in adults. 34 Recent evidence indicates that children and adolescents with high ApoB and low ApoA1 concentrations may show signs of atherosclerosis at earlier ages than those of the same age with normal concentrations of these biochemical parameters. 35 Scientific evidence highlights that exposure to these risk factors in the first cycles of life can contribute to the development of cardiovascular changes in later periods of life. 31,36 Applicability of Evidence It is known that CVDs have a great impact on the population’s morbidity and mortality, and therefore require substantial public investment in health care. When determining the robust relationship between excess adiposity and apolipoproteins—investigated in this study—, the results may have important implications from the point of view of formulating policies for the prevention, screening and early detection of subjects at risk, favoring the construction of measures to cope with this health problem. Potential Biases in the Review Process Although this investigation was well designed and conducted, it has limitations inherent to meta-analysis studies, especially with regard to the lack of information, Figure 5 – Forest plot of the influence of excess body adiposity on the difference of the weighted mean of ApoA1 according to the age of children and adolescents. Falaschetti et al. 1 and 3: correspond to overweight and obese boys, respectively. Falaschetti et al. 2 and 4: correspond to overweight and obese girls, respectively. in primary studies, on the variables that would allow investigating high heterogeneity between studies. In this study, the influence of the variables age, sex, mean BMI and sample size on the meta-regression was investigated, since only for these there was information available in all studies. It is known that the presence of hypothyroidism can raise ApoB levels, 37,38 an important variable to assess possible causes of heterogeneity; however, none of the studies included in our analysis referred to the presence or absence of this disorder in the individuals evaluated. The small number of studies addressing this object limited the possibility of analyzing the risk of publication bias by funnel plot. However, some authors question the real usefulness of this instrument for this purpose, considering that the interpretation of its asymmetry is subjective, and there may be errors of interpretation regarding the risk of publication bias. In addition, some effect estimates (OR or mean differences) produced using the funnel plot are naturally correlated with their standard errors, which can produce a false asymmetry and confusion with publication bias. 39 Many studies had a cross-sectional design, which did not allow the phenomenon of interest to be evaluated, which is naturally longitudinal. Studies with a prospective design, but which measured ApoB and ApoA1 in a single moment, were included under the justification that, in children under nine years old, these changes were not clinically important, 25 a situation that can lead to selection and underreporting bias. 169