Association between Serum Phytosterols and Lipid Levels in a Population-Based Study

The association between phytosterols and lipid levels remains poorly assessed at a population level. We assessed the associations between serum levels of six phytosterols (campesterol, campestanol, stigmasterol, sitosterol, sitostanol and brassicasterol) and of lipids [total, low-density lipoprotein (LDL)- and high-density lipoprotein (HDL)-cholesterol, triglycerides, apolipopoprotein A-IV and lipoprotein Lp(a)] in two cross-sectional surveys of a population-based, prospective study. Data from 910 participants (59.1% women, 70.4 ± 4.7 years) for the first survey (2009-2012) and from 721 participants (60.2% women, 75.1 ± 4.7 years) for the second survey (2014-2017) were used. After multivariable adjustment, all phytosterols were positively associated with total cholesterol: slope and (95% confidence interval) 1.594 (1.273-1.915); 0.073 (0.058-0.088); 0.060 (0.044-0.076); 2.333 (1.836-2.830); 0.049 (0.033-0.064) and 0.022 (0.017-0.028) for campesterol, campestanol, stigmasterol, sitosterol, sitostanol and brassicasterol, respectively, in the first survey, and 1.257 (0.965-1.548); 0.066 (0.052-0.079); 0.049 (0.034-0.063); 1.834 (1.382-2.285); 0.043 (0.029-0.057) and 0.018 (0.012-0.023) in the second survey, all < 0.05. Similar positive associations were found between all phytosterols and LDL cholesterol. Positive associations were found between campesterol and sitosterol and HDL-cholesterol: slope and (95% CI) 0.269 (0.134-0.405) and 0.393 (0.184-0.602) for campesterol and sitosterol, respectively, in the first survey, and 1.301 (0.999-1.604) and 0.588 (0.327-0.849) in the second survey, all < 0.05. No associations were found between phytosterols and triglyceride or lipoprotein Lp(a) levels, while a positive association between campesterol and apolipoprotein A-IV levels was found: 2.138 (0.454-3.822). Upon normal dietary intakes, serum phytosterol levels were positively associated with total and LDL cholesterol levels, while no consistent association with other lipid markers was found.