IJCS | Volume 31, Nº4, July / August 2018

368 Cunha et al. Lipid profile in adolescents Int J Cardiovasc Sci. 2018;31(4)367-373 Original Article Knowing that dyslipidemia is associatedwith CVD, its diagnosis in adolescence can reduce the chances of future complications, because a change in lifestyle to healthier habits can be the best prevention. 11,12 This study was aimed at assessing the lipid profile of adolescents of the municipality of Araucária, Paraná state. It collected data of 600 adolescents aged 10 to 19 years and compared them to those of studies conducted in other regions of Brazil. Methods This study was approved by the Ethics Committee in Research of the Instituto Paranaense de Otorrinolaringologia and is registered under the number 65932917.0.0000.5529, according to the Resolution 466/12 of the National Board of Health of the Ministry of Health, which regulates research with human beings. The results of 600 lipid profiles were collected from the Araucária Municipal Laboratory, which had been approved by the local coordinator, so that the study could begin even before approval by the Ethics Committee in Research. This is a cross-sectional, retrospective study with convenience sampling of the lipid profile of 600 adolescents aged 10 to 19 years, through systematic random sampling, from July to December 2016. Tests with TG levels greater than 400 mg/dL were excluded. The samples were collected 5-mL tubes containing serum separating gel and particles to activate clotting, and were tested by enzymatic photometric assay (Abbott Architect c8000), using the direct precipitation method for HDL-c quantitation (UltraHDL). To calculate VLDL-c, the TG level was divided by 5, and to calculate LDL-c, the Friedewald formula was used. The collected data were organized in Excel 2007 sheets and stratified as TC, LDL-c, HDL-c, non-HDL-c (sum of the lipoproteins without HDL), VLDL-c and TG, in addition to age and sex of the adolescents, being identified by codes and organized in tables and graphs. Statistical analysis The descriptive statistical analysis included percentage and median with respective interquartile range (IQR). Continuous variables were expressed as median and IQR, because they had no normal distribution, while categorical variables were expressed as percentages. Normality was assessed by use of the Kolmogorov- Smirnov test. The statistical analysis comprised Mann- Whitney U test and Spearman coefficient of correlation (S), using the SPSS software 2.0. The adopted significance level was 5% of probability and 95% confidence interval, and all tests were two-tailed. Results The lipid profiles of 600 adolescents aged 10 to 19 years from the AraucáriaMunicipal Laboratory were assessed. Of the 600 adolescents, 322 (54%) were of the female sex and 278 (46%) were of the male sex. Table 1 shows the analyzed data, which, in 1.83% (n = 11) of the adolescents, it is suggested familial hypercholesterolemia. 10 Tables 2, 3 and 4 show the correlations between the lipids, where 1 means perfect positive correlation, that is, when one variable increases, the other increases at the same intensity, and -1 means perfect negative correlation, that is, when one variable increases, the other decreases at the same intensity. When comparing between sexes, the female sex had a higher TC than that of the male sex (Figure 1A). Regarding non-HDL-c, the female sex had a median of 109 and IQR of 40.25, while the male sex had a median of 101 and IQR of 32.25, with no significant difference between them. In addition, in the non-stratified sample, positive correlations of non-HDL-c were found with TG, TC and VLDL-c as compared to LDL-c, and fewer negative correlations with HDL-c (Table 2). In adolescents aged 10 to 14 years, more positive correlations of non-HDL-c with TG, TC and VLDL-c were found as compared to LDL-c, and some negative correlations of LDL-c, TC and non-HDL-c with age (Table 3). When comparing between sexes, only TG showed a difference (Figure 1B). Regarding sexes, in adolescents aged 15 to 19 years, the correlations showed the same trend of the other age group (Table 4), and the comparisons between sexes achieving significance for the LDL-c (Figure 1C) and TC (Figure 1D), while the other lipids showed no statistically significant variation. Discussion The study by Silva et al. 11 has reported desirable values of TC of 50%, similar to those found in the present study (49%), but different from the 37% reported by Araki et al. 13 This difference was observed in a study conducted in the city of Aracaju, Sergipe state, which has found a higher TC value in the female sex as compared to that in the male sex, a result that corroborates that found