ABSTRACT
Genetic variation in fatty acid desaturases (FADS) has previously been linked to long-chain polyunsaturated fatty acids (PUFAs) in adipose tissue and cardiovascular risk. The goal of our study was to test associations between six common FADS polymorphisms (rs174556, rs3834458, rs174570, rs2524299, rs174589, rs174627), intermediate cardiovascular risk factors, and non-fatal myocardial infarction (MI) in a matched population based case-control study of Costa Rican adults (n = 1756). Generalized linear models and multiple conditional logistic regression models were used to assess the associations of interest. Analyses involving intermediate cardiovascular risk factors and MI were also conducted in two replication cohorts, The Nurses' Health Study (n = 1200) and The Health Professionals Follow-Up Study (n = 1295). In the Costa Rica Study, genetic variation in the FADS cluster was associated with a robust linear decrease in adipose gamma-linolenic, arachidonic, and eicosapentaenoic fatty acids, and significant or borderline significant increases in the eicosadienoic, eicosatrienoic, and dihomo-gamma-linolenic fatty acids. However, the associations with adipose tissue fatty acids did not translate into changes in inflammatory biomarkers, blood lipids, or the risk of MI in the discovery or the replication cohorts. In conclusion, fatty acid desaturase polymorphisms impact long-chain PUFA biosynthesis, but their overall effect on cardiovascular health likely involves multiple pathways and merits further investigation.
ABSTRACT
BACKGROUND/OBJECTIVES: Elongases 2, 4 and 5, encoded by genes ELOVL2, ELOVL4 and ELOVL5, have a key role in the biosynthesis of very long chain polyunsaturated fatty acids (PUFAs). To date, few studies have investigated the associations between elongase polymorphisms and cardiovascular health. We investigated whether ELOVL polymorphisms are associated with adipose tissue fatty acids, serum lipids, inflammation and ultimately with nonfatal myocardial infarction (MI) in a Costa Rican population. SUBJECTS/METHODS: MI cases (n=1650) were matched to population-based controls (n=1650) on age, sex and area of residence. Generalized linear and multiple conditional logistic regression models were used to assess the associations between seven common ELOVL polymorphisms and cardiometabolic outcomes. Analyses were replicated in The Nurses' Health Study (n=1200) and The Health Professionals Follow-Up Study (n=1295). RESULTS: Variation in ELOVL2, ELOVL4 and ELOVL5 was not associated with adipose tissue fatty acids, intermediate cardiovascular risk factors or MI. In the Costa Rica study, the number of the minor allele copies at rs2294867, located in the ELOVL5 gene, was associated with an increase in total and LDL cholesterol (adjusted P-values=0.001 and <0.0001 respectively). Additionally, the number of the minor allele copies at rs761179, also located in the ELOVL5 gene, was significantly associated with an increase in total cholesterol (adjusted P-value=0.04). However, the observed associations were not replicated in independent populations. CONCLUSION: Common genetic variants in elongases are not associated with adipose tissue fatty acids, serum lipids, biomarkers of systemic inflammation, or the risk of MI.
Subject(s)
Acetyltransferases/genetics , Cardiovascular Diseases/genetics , Cholesterol/genetics , Fatty Acids, Unsaturated/genetics , Inflammation/genetics , Myocardial Infarction/genetics , Polymorphism, Genetic , Adipose Tissue/metabolism , Aged , Alleles , Case-Control Studies , Cholesterol/blood , Cholesterol, LDL/blood , Cholesterol, LDL/genetics , Costa Rica , Fatty Acid Elongases , Fatty Acids, Unsaturated/biosynthesis , Female , Genotype , Humans , Logistic Models , Male , Middle Aged , Phenotype , Risk FactorsABSTRACT
AIMS: To examine whether the association between prevalence measures of suicidality and substance abuse/dependence among adolescents (1) is attenuated when temporal priority of exposure and outcome are taken into account, (2) extends to substance use (i.e. without disorder), (3) applies to tobacco use and dependence independent of illicit drugs and alcohol use/disorder, and (4) is confounded by comorbid mental illness. DESIGN: Discrete-time survival models were applied to retrospectively reported age of onset of first suicidal ideation, plan and attempt and age of onset of first substance use and disorder. PARTICIPANTS: 3005 adolescents aged 12-17 residing in the Mexico City Metropolitan Area in 2005. MEASUREMENTS: The World Mental Health computer-assisted adolescent version of the Composite International Diagnostic Interview was used to assess suicidal outcomes and psychiatric disorders including substance dependence/abuse. FINDINGS: Use of and dependence on tobacco is as strong a predictor of subsequent suicidality as is use of and dependence with abuse of alcohol and drugs. The association between substance use and subsequent suicidality is not fully accounted for by comorbid mental illness. CONCLUSION: Efforts to reduce the use as well as the abuse of alcohol, drugs and tobacco may help reduce the risk of subsequent suicidal behaviors among adolescents in Mexico.