BACKGROUND AND AIMS: Polyunsaturated fatty acids (PUFA) may play a role in the etiology of the metabolic syndrome (MetS). The aim of the study was to examine the associations of adipose tissue PUFA biomarkers with MetS among parents and children in Mesoamerica.
METHOD AND RESULTS: We conducted a cross-sectional study among 468 parents and 201 children aged 7-12 y from the capital cities of Guatemala, El Salvador, the Dominican Republic, Honduras, Nicaragua, Panama, Costa Rica, and Belize, and Tuxtla Gutiérrez in Mexico. We measured PUFA biomarkers in gluteal adipose tissue by gas chromatography. In adults, MetS was defined according to the National Cholesterol Education Program’s Adult Treatment Panel III definition. In children, we created an age- and sex-standardized metabolic risk score using abdominal circumference, the homeostasis model of insulin resistance, blood pressure, serum HDL cholesterol, and triglycerides. We estimated prevalence ratios of MetS and mean differences in metabolic score across quartiles of PUFA using multivariable-adjusted Poisson and linear regression models, respectively. Among adults, MetS was associated with low alpha-linolenic acid (ALA), high eicosapentaenoic acid (EPA), and low gamma-linolenic acid (GLA). It was linearly, positively associated with dihomo-gamma-linolenic acid (DGLA) and estimated Δ6-desaturase (D6D) activity. Among children, the metabolic score was positively associated with docosapentaenoic acid (DPA), DGLA, and D6D activity. CONCLUSIONS: Among Mesoamerican adults, MetS prevalence is inversely associated with adipose tissue ALA and GLA, and positively associated with EPA, DGLA, and the D6D index. Among children, metabolic risk score is positively associated with DPA, DGLA, and the D6D index.
Link to Full Text
The metabolic syndrome (MetS) is a clustering of cardiometabolic risk factors that is associated with increased risk of cardiovascular disease, diabetes, and mortality. The essential FA a-linolenic acid (18:3 n-3; ALA) and linoleic acid (18:2 n-6; LA) may be inversely related to
MetS, but evidence is limited. Additionally, the relation between PUFA status and cardiometabolic health in childhood is uncertain.
In this cross-sectional study of Mesoamerican families, it was found that, among adults, MetS prevalence was inversely associated with adipose tissue ALA but positively related to EPA. In addition, MetS was inversely related to GLA but positively to DGLA and D6D. In children, DPA, DGLA, and D6D were positively associated with an overall metabolic risk score. The inverse association between ALA and MetS among Mesoamerican adults is in line with results from previous studies. Of three cross-sectional investigations of adipose tissue ALA and MetS or its components, two found inverse associations with insulin resistance and one found inverse relations with MetS, high waist circumference, and fasting glucose. The main strength of this study is the use of the gold standard for assessing long-term FA intake, adipose tissue. In conclusion, among adults MetS prevalence is inversely associated with adipose tissue ALA and GLA, and positively associated with EPA, DGLA, and D6D activity. Among children, metabolic risk score is positively associated with adipose tissue DPA, DGLA, and D6D activity. Future studies should assess these associations using longitudinal designs. A potential protective effect of ALA against MetS warrants further investigation, since ALA status can be easily enhanced through relatively simple dietary interventions.