Consensus document for lipid profile testing and reporting in Spanish clinical laboratories: What parameters should a basic lipid profile include?

Cardiovascular diseases (CVD) continue to be the main cause of death in our country. Adequate control of lipid metabolism disorders is a key challenge in cardiovascular prevention that is far from being achieved in real clinical practice. There is a great heterogeneity in the reports of lipid metabolism from Spanish clinical laboratories, which may contribute to its poor control. For this reason, a working group of the main scientific societies involved in the care of patients at vascular risk, has prepared this document with a consensus proposal on the determination of the basic lipid profile in cardiovascular prevention, recommendations for its realization and unification of criteria to incorporate the lipid control goals appropriate to the vascular risk of the patients in the laboratory reports.

Consensus document for lipid profile testing and reporting in Spanish clinical laboratories

Cardiovascular diseases (CVD) continue to be the main cause of death in our country. Adequate control of lipid metabolism disorders is a key challenge in cardiovascular prevention that is far from being achieved in real clinical practice. There is a great heterogeneity in the reports of lipid metabolism from Spanish clinical laboratories, which may contribute to its poor control. For this reason, a working group of the main scientific societies involved in the care of patients at vascular risk, has prepared this document with a consensus proposal on the determination of the basic lipid profile in cardiovascular prevention, recommendations for its realization and unification of criteria to incorporate the lipid control goals appropriate to the vascular risk of the patients in the laboratory reports.

Consensus document for lipid profile determination and reporting in Spanish clinical laboratories. What parameters should be included in a basic lipid profile?

Cardiovascular diseases (CVD) continue to be the main cause of death in our country. Adequate control of lipid metabolism disorders is a key challenge in cardiovascular prevention that is far from being achieved in real clinical practice. There is a great heterogeneity in the reports of lipid metabolism from Spanish clinical laboratories, which may contribute to its poor control. For this reason, a working group of the main scientific societies involved in the care of patients at vascular risk, has prepared this document with a consensus proposal on the determination of the basic lipid profile in cardiovascular prevention, recommendations for its realization and unification of criteria to incorporate the lipid control goals appropriate to the vascular risk of the patients in the laboratory reports.

Consensus document for lipid profile testing and reporting in Spanish clinical laboratories: what parameters should a basic lipid profile include?

Cardiovascular diseases (CVD) continue to be the main cause of death in our country. Adequate control of lipid metabolism disorders is a key challenge in cardiovascular prevention that is far from being achieved in real clinical practice. There is a great heterogeneity in the reports of lipid metabolism from Spanish clinical laboratories, which may contribute to its poor control. For this reason, a working group of the main scientific societies involved in the care of patients at vascular risk, has prepared this document with a consensus proposal on the determination of the basic lipid profile in cardiovascular prevention, recommendations for its realization and unification of criteria to incorporate the lipid control goals appropriate to the vascular risk of the patients in the laboratory reports.

[Consensus document for lipid profile determination and reporting in Spanish clinical laboratories]

Cardiovascular diseases (CVD) continue to be the main cause of death in our country. Adequate control of lipid metabolism disorders is a key challenge in cardiovascular prevention that is far from being achieved in real clinical practice. There is a great heterogeneity in the reports of lipid metabolism from Spanish clinical laboratories, which may contribute to its poor control. For this reason, a working group of the main scientific societies involved in the care of patients at vascular risk, has prepared this document with a consensus proposal on the determination of the basic lipid profile in cardiovascular prevention, recommendations for its realization and unification of criteria to incorporate the lipid control goals appropriate to the vascular risk of the patients in the laboratory reports.

Handling of lipemic samples in the clinical laboratory

Interferences in the clinical laboratory may lead physicians misinterpret results for some biological analytes. The most common analytical interferences in the clinical laboratory include hemolysis, icterus and lipemia. Lipemia is defined as turbidity in a sample caused by the accumulation of lipoproteins, mainly very-low density lipoproteins (VLDL) and chylomicrons. Several methods are available for the detection of lipemic samples, including the lipemic index, or triglyceride quantification in serum or plasma samples, or mean corpuscular hemoglobin (MCHC) concentration in blood samples. According to the European Directive 98/79/CE, it is the responsibility of clinical laboratories to monitor the presence of interfering substances that may affect the measurement of an analyte. There is an urgent need to standardize interference studies and the way interferences are reported by manufacturers. Several methods are currently available to remove interference from lipemia and enable accurate measurement of biological quantities. The clinical laboratory should establish a protocol for the handling of lipemic samples according to the biological quantity to be tested.

Geostatistical analysis from the clinical laboratory in cardiovascular prevention for primary care

INTRODUCTION AND OBJECTIVES

Cardiovascular diseases continue to lead the ranking of mortality in Spain. The implementation of geostatistical analysis techniques in the clinical laboratory are innovative tools that allow the design of new strategies in primary prevention of cardiovascular disease. The aim of this study was to study the prevalence and geolocation of severe dyslipidemia in the health areas under study in order to implement prevention strategies in primary care. A retrospective cohort study of low-density protein-bound cholesterol, triglyceride and lipoprotein (a) levels in the years 2019 and 2020 were carried out. In addition, a geostatistical analysis was performed including representation in choropleth maps and the detection of clustering clusters, using geographic information in zip code format included in the demographic data of each analytic.

RESULTS

The analytical data included in the study were triglycerides (n=365,384), low density protein-bound cholesterol (n=289,594) and lipoprotein to lipoprotein (a) (n=502). Areas with the highest and lowest percentage of cases were identified for the established cut-off points of LDL-C>190mg/dL and TG>150mg/dL. Two clustering clusters with statistical significance were detected for cLDL>190mg/dL and a total of 6 clusters for TG values>150mg/dL.

CONCLUSIONS

The detection of clusters, as well as the representation of choropleth maps, can be of great help in detecting geographic areas that require greater attention to intervene and improve cardiovascular risk.

Consensus document for lipid profile determination and reporting in Spanish clinical laboratories. What parameters should be included in a basic lipid profile?

Cardiovascular diseases (CVD) continue to be the main cause of death in our country. Adequate control of lipid metabolism disorders is a key challenge in cardiovascular prevention that is far from being achieved in real clinical practice. There is a great heterogeneity in the reports of lipid metabolism from Spanish clinical laboratories, which may contribute to its poor control. For this reason, a working group of the main scientific societies involved in the care of patients at vascular risk, has prepared this document with a consensus proposal on the determination of the basic lipid profile in cardiovascular prevention, recommendations for its realization and unification of criteria to incorporate the lipid control goals appropriate to the vascular risk of the patients in the laboratory reports.

Implementation of a biochemical, clinical, and genetic screening programme for familial hypercholesterolemia in 26 centres in Spain: The ARIAN study

Background: Familial hypercholesterolemia (FH) is clearly underdiagnosed and undertreated. The aim of this present study is to assess the benefits of FH screening through a joint national program implemented between clinical laboratories and lipid units.

Methods: All clinical laboratory tests from 1 January 2017 to 31 December 2018 were reviewed, and those with LDL cholesterol (LDL-C) levels >250 mg/dl were identified in subjects >18 years of age of both sexes. Once secondary causes had been ruled out, the treating physician was contacted and advised to refer the patient to an LU to perform the Dutch Lipid Clinic Network score and to request genetic testing if the score was ≥6 points. Next Generation Sequencing was used to analyse the promoter and coding DNA sequences of four genes associated with FH (LDLR, APOB, PCSK9, APOE) and two genes that have a clinical overlap with FH characteristics (LDLRAP1 and LIPA). A polygenic risk score based on 12 variants was also obtained.

Results: Of the 3,827,513 patients analyzed in 26 centers, 6,765 had LDL-C levels >250 mg/dl. Having ruled out secondary causes and known cases of FH, 3,015 subjects were included, although only 1,205 treating physicians could be contacted. 635 patients were referred to an LU and genetic testing was requested for 153 of them. This resulted in a finding of sixty-seven pathogenic variants for FH, 66 in the LDLR gene and one in APOB. The polygenic risk score was found higher in those who had no pathogenic variant compared to those with a pathogenic variant.

Conclusion: Despite its limitations, systematic collaboration between clinical laboratories and lipid units allows for the identification of large numbers of patients with a phenotypic or genetic diagnosis of FH, which will reduce their vascular risk. This activity should be part of the clinical routine.

Incorporation of biochemical parameters and diagnostic algorithms in the laboratory computer system for the early detection of lipid abnormalities from the lipid units

INTRODUCTION

The combination of biochemical markers, together with the design and implementation of diagnostic algorithms in laboratory computer systems could become very powerful tools in the stratification of cardiovascular risk.

OBJECTIVES

To implement new biochemical markers and diagnostic algorithms not yet available, in order to provide an estimation of cardiovascular risk and the diagnostic orientation of lipid alterations.

MATERIAL AND METHODS

Study of the implementation of apolipoprotein B and lipoprotein (a), as well as the inclusion of different diagnostic algorithms. This was carried out jointly by the different Lipid Units of the Spanish Society of Atherosclerosis, Hospital Virgen Macarena in Seville, Hospital Juan Ramón Jiménez, Hospital Infanta Elena, and Hospital de Río Tinto during 2018 and 2019.

RESULTS

The 4diagnostic algorithms entered into the Laboratory Information System, showed a total of 9,985 patients with c-LDL>200mg/dl. The diagnostic algorithm was extended to include Apo B, with 8,182 determinations showing an apolipoprotein B>100mg/dl). A total of 747 lipoprotein (a) were determined, of which 30.65% were> 50mg/dl. More than 2/3 (71.80%) showed results compatible with small and dense LDL particles.

CONCLUSIONS

The implementation of new analytical parameters and algorithms in Primary Care laboratory results can identify a considerable number of patients with different alterations in lipid metabolism. This, together with the classic risk factors, could contribute to a correct risk stratification in preventing the progression of cardiovascular disease.

Prevalence of severe hypercholesterolemia observed in different hospitals in Andalusia and Ceuta

Severe hypercholesterolaemia is a major cardiovascular risk factor. Early detection and treatment can reduce the incidence of cardiovascular disease. Given the high prevalence of hypercholesterolaemia in Andalusia, the development of a screening strategy for its detection in Primary Care may be an efficient measure.

OBJECTIVE

To identify patients in Primary Care with severe hypercholesterolaemia that may increase their cardiovascular risk by reviewing LDL-cholesterol results in computerised laboratory systems.

MATERIAL AND METHODS

Observational, retrospective, multi-centre study in 16 hospitals in Andalusia and Ceuta. Anonymous analytical data were acquired from the different laboratory computer systems for the year 2018, and exclusively from Macarena Hospital for the year 2019.

RESULTS

From a total of 1,969,035 determinations on≥18 years old, 2,791 patients (0.14%) were detected with LDL-cholesterol>250mg/dl and from a total of 2.327.211 determinations studied in children under 18 years old, 3,804 patients (0.16%) were detected with LDL-cholesterol>135mg/dL. The highest incidence of possible genetic hypercholesterolaemia in adults corresponded to the province of Seville with 23.6 cases/1,000 determinations, while in minors, the highest incidence corresponded to the province of Cadiz with 75 possible cases/1,000 determinations. A geographical triangle of greater prevalence is observed between the provinces of Seville, Huelva and Cadiz.

CONCLUSIONS

The development of a screening strategy using a computerised review of LDL-cholesterol in Primary Care detects a large number of subjects with severe hypercholesterolaemia that could benefit from an early intervention.

Implantation of a biochemical and genetic screening programme for family hypercholesterolaemia. Collaboration between the clinical laboratory and lipid units: Design of the ARIAN Project

INTRODUCTION AND OBJECTIVE

Familial hypercholesterolaemia (FH) is the most common genetic disorder associated with premature coronary artery disease due to the presence of LDL-C cholesterol increased from birth. It is underdiagnosed and undertreated. The primary objective of the ARIAN project was to determine the number of patients diagnosed with FH after implementing a new screening procedure from the laboratory.

MATERIAL AND METHODS

This project was designed as a retrospective analysis by consulting the computer system. We selected from databases serum samples from patients ≥ 18 years with direct or calculated LDL-C>250mg/dL from 1 January 2017 to 31 December 2018. Once secondary causes had been ruled out, the requesting primary care physician was notified that their patient might have FH and to arrange a priority appointment in the lipid unit. All patients with a score of ≥ 6 points according to the Dutch Lipid Clinic Criteria were proposed for a genetic study RESULTS: By December 30th, 2020, 24 centres out of the initial 55 had submitted results. The number of patients analysed up to that point was 3,266,341, which represents 34% of the population served in those health areas (9,727,434).

CONCLUSIONS

The identification of new subjects with FH through this new strategy from the laboratory and their referral to lipid units should increase the number of patients treated in lipid units and initiate familial cascade screening.

Genetics and biochemistry of familial hypercholesterolemia in Southwest of the Iberian Peninsula

So far, most cases of hypercholesterolaemia (60-80%) are attributed to pathogenic variants in the LDLR gene. Only 1-5% of cases are caused by variants in the APOB gene, and 0-3% by variants in the PCSK9 gene. There is a large variety in known pathogenic mutations of the LDLR gene, while for those affecting the APOB gene, the highest incidence is p.Arg3527Gln, described predominantly in Central European and North American populations. In the Iberian Peninsula the predominant gene affected is that of the LDL receptor, similar to the rest of the world, with the involvement of the APOB gene being described in individuals from the northwest, and anecdotal in the rest of the territory. A genetics analysis was performed on the population attending the first year of a lipid clinic in southwestern Spain with a 6-point score from the Dutch lipid clinics. The genetic, biochemical and clinical findings are described. The first findings show indications of a possible higher prevalence of patients with mutation in the APOB gene compared to other territories. Historical evidence is presented that could give a possible explanation to this, thus supporting the assumption.

[Increased lipoprotein(a) in a paediatric patient associated with nephrotic syndrome]

A common complication in paediatric patients with nephrotic syndrome (NS) is hyperlipidaemia. About 20% of children do not respond to treatment with corticosteroids, presenting with a cortico-resistant NS (CRNS), which can progress to kidney failure. It has been observed that paediatric patients with CRNS have an elevated low density lipoprotein cholesterol (LDL-c), very low density lipoprotein cholesterol (VLDL-c), and triglycerides levels, as well as elevated Lipoprotein-a [Lp (a)] levels. The case is presented of a 5 year old boy, diagnosed with CRNS, presenting with dyslipidaemia with increased LDL-c, Apo-B100, and Lp(a) levels. After the poor prognosis of the renal function, immunosuppressant treatment was started with tacrolimus and atorvastatin to control dyslipidaemia. Although tacrolimus causes an elevation of total cholesterol and LDL-c, the significant alterations of the children lipid profile suggest the existence of a high cardiovascular risk. In these cases, it would be interesting to have reference values in children in our health area.