BACKGROUND: Various studies confirm that the prevalence of dyslipidemia and other cardiovascular factors is high. OBJECTIVE: To evaluate the trend of the lipid profile (LP) in a cohort with severe hypercholesterolemia and its relationship with lipid-lowering treatment during the period 2009-2021. METHODS: Cross-sectional study carried out in the Osona county (Barcelona). Outpatients from the first period (2009-2011) who were aged between 25 and 65 years and had severe hypercholesterolemia were selected (n = 2,608). In a second period (2019-2021), these patients (n = 1,855) were followed up to evaluate the trend of LP and its relationship with lipid-lowering treatment. The Student's T-test (paired data) was used to identify differences between observations from the two periods. RESULTS: Lipid-lowering treatment was prescribed to 61.9% of patients. The group of patients of the cohort improved the data of the mean results of the LP. Approximately 75% of cases were unable to establish their cholesterol and atherogenic fraction values. The prescription of lipid-lowering treatment in the cardiovascular disease group (CVD) was 80.9% vs 61.9% of the total cohort. CONCLUSION: Three out of four cases failed to reduce the levels of LDL-C and non-HDL-C, recommended by the guidelines of scientific societies. Primary Care is the ideal framework to implement improvement strategies to control severe hypercholesterolemia, and it is therefore essential to strengthen it.