IJCS | Volume 33, Nº4, July and August 2020

342 Table 1 - Distribution of clinical characteristics of women´s participants (n = 164) by WC categories according to IDF and NCEP-ATPIII cutoff points IDF NCEP-ATPIII WC < 80 cm n = 26 WC ≥ 80 cm n = 138 WC ≤ 88 cm n = 53 WC > 88 cm n = 111 Age (years) 35.11 ± 10.5 44.6 ± 10.1* 39.7 ± 10.8 44.7 ± 10.3* WC (cm) 73.3 ± 4.4 100.4 ± 14.3* 79.3 ± 7.0 104.1 ± 13.5* SBP (mmHg) 116.0 ± 10.7 128.7 ± 15.3 # 120.4 ± 15.2 129.7 ± 14.4 # DBP (mmHg) 74.7 ± 8.4 84.9 ± 11.0* 77.3 ± 9.4 86.1 ± 10.9* Glucose (mg/dL) 93.1 ± 57.3 90.7 ± 40.0# 88.9 ± 42.1 92.1 ± 43.5 HDL-c (mg/dL) 49,2 ± 9.4 49.2 ± 11.2* 50.6 ± 9.0 48.5 ± 11.6 Triglycerides (mg/dL) 111.4 ± 51.6 130.4 ± 74.5* 115.2 ± 47.1 133.2 ± 80.3 Data are expressed as mean ± SD. WC: waist circumference; SBP: systolic blood pressure; DBP: diastolic blood pressure; HDL-c: high density lipoprotein-cholesterol. # p < 0.05, compared with normal WC (Student´s t test), assuming equal variances. * p < 0.05, compared with normal WC (Mann-Whitney U test). distributed into two WC categories according to the IDF and NCEP-ATPIII cut-off values. The Shapiro-Wilk test was used to assess the normality of all dependent variables (age, WC, SBP, DBP, serum glucose, HDL- cholesterol, and triglycerides) distributed into the WC categories and age groups. Comparison of data between WC categories were made by unpaired Student’s t test (with Levene’s test for equality of variance) and the Mann-Whitney U-test for data with normal and non- normal distribution, respectively. Values between age groups were compared with Kruskal-Wallis test. For correlation and regression analyses, WC was the independent variable and SBP, DBP, glucose, HDL- cholesterol, and triglycerides the dependent variables. The strength of the association betweenWC (categorized as normal or increased) and the variables SBP, DBP, serum glucose, HDL-cholesterol, and triglycerides was measured by Spearman’s rho (ρ) correlation coefficient. The size of the correlation coefficient was interpreted according to Mukaka 14 in which the correlation between 0.00 and 0.30 was considered as negligible, 0.30 and 0.50 as low, 0.50 and 0.70 as moderate, 0.70 and 0.90 as high, and 0.90 and 1.00 as very high. Participants were divided into three age groups: < 40, 40-50, and > 50 years, and correlations between WC and other variables were also assessed according to these groups. Simple and hierarchical linear regression analysis was used to examine the relationship between increased WC and cardiometabolic risk factors, and to estimate the explained variance (R square, R2 ) of these risk factors by WC. First, on simple linear regression analysis, the anthropometric measure (normal and increasedWC) was included as an independent variable, and then each variable (SBP, DBP, serum glucose, HDL- cholesterol, and triglycerides) was tested as a dependent variable. All data related to cardiometabolic risk factors were also divided into normal and altered groups according to the IDF and NCEP-ATPIII criteria. On regression studies, all variables were log transformed to meet the requirements of the analysis. A p value < 0.05 was considered statistically significant. Results The study included 164 participants with amedian age of 44.0 years [IQR13.75]. Median [IQR] of WC, SBP, DBP, glucose, HDL-c and triglycerides in the overall cohort was 94.2 [IQR18.5]cm, 127.0 [IQR 20] mm Hg, 81.0 [IQR 14] mm Hg, 86.0 [IQR 18] mg/dL, 48.0 [IQR 13] mg/dL and 117.5 [IQR 68.5] mg/dL, respectively. Results of the median or mean ± SD of age, SBP, DBP, glucose, HDL-c and triglycerides values were compared according to WC categories defined by IDF and NCEP- ATP III criteria (Table 1). Compared with normal WC participants, the group with increased WC was older, and showed higher levels of WC, SBP and DBP (all p < 0.05). In contrast, levels of glucose, HDL-cholesterol, Silva et al Waist circumference and increased blood pressure Int J Cardiovasc Sci. 2020; 33(4):340-347 Original Article