title: Structural equation modeling for analyzing erythrocyte fatty acids in Framingham.
abstract: Research has shown that several types of erythrocyte fatty acids (i.e., omega-3, omega-6, and trans) are associated with risk for cardiovascular diseases. However, there are complex metabolic and dietary relations among fatty acids, which induce correlations that are typically ignored when using them as risk predictors. A latent variable approach could summarize these complex relations into a few latent variable scores for use in statistical models. Twenty-two red blood cell (RBC) fatty acids were measured in Framingham (N = 3196). The correlation matrix of the fatty acids was modeled using structural equation modeling; the model was tested for goodness-of-fit and gender invariance. Thirteen fatty acids were summarized by three latent variables, and gender invariance was rejected so separate models were developed for men and women. A score was developed for the polyunsaturated fatty acid (PUFA) latent variable, which explained about 30% of the variance in the data. The PUFA score included loadings in opposing directions among three omega-3 and three omega-6 fatty acids, and incorporated the biosynthetic and dietary relations among them. Whether the PUFA factor score can improve the performance of risk prediction in cardiovascular diseases remains to be tested.
authors: Health Diagnostic Laboratory Inc., Richmond, VA 23219, USA ; Department of Internal Medicine, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD 57105, USA.
authors: James V
authors: JV
authors: Pottala
authors: Department of Mathematics and Statistics, South Dakota State University, Brookings, SD 57007, USA.
authors: Gemechis D
authors: GD
authors: Djira
authors: Department of Biostatistical Sciences, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
authors: Mark A
authors: MA
authors: Espeland
authors: Department of Statistics, University of Akron, Akron, OH 44325, USA.
authors: Jun
authors: 0000-0003-0465-8259
authors: J
authors: Ye
authors: Department of Biostatistics, Boston University School of Public Health, Boston, MA 02218, USA ; Department of Mathematics and Statistics, Boston University, Boston, MA 02215, USA ; Framingham Heart Study, Framingham, MA 01702, USA.
authors: Martin G
authors: MG
authors: Larson
authors: Health Diagnostic Laboratory Inc., Richmond, VA 23219, USA ; Department of Internal Medicine, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD 57105, USA ; OmegaQuant Analytics, Sioux Falls, SD 57107, USA.
authors: William S
authors: WS
authors: Harris
mesh_terms: D000368:Aged; D000465:Algorithms; D002318:Cardiovascular Diseases / Q000175:diagnosis*; D019295:Computational Biology / Q000379:methods; D003627:Data Interpretation, Statistical; D004912:Erythrocytes / Q000166:cytology / Q000378:metabolism*; D005163:Factor Analysis, Statistical; D005227:Fatty Acids / Q000737:chemistry*; D005231:Fatty Acids, Unsaturated / Q000737:chemistry; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D015999:Multivariate Analysis; D012307:Risk Factors; D012737:Sex Factors; D012984:Software
chemical_list: D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated