What characterizes event-free elderly FH patients? A comprehensive lipoprotein profiling

Adherence to the Healthy Nordic Food Index is associated with reduced plasma levels of inflammatory markers in patients with heterozygous familial hypercholesterolemia

Background and aims

Familial hypercholesterolemia (FH) is an inherited disease associated with hypercholesterolemia, and dietary treatment is part of the treatment. We aimed to assess the dietary pattern in relation to the Healthy Nordic Food Index (HNFI) in adults with and without heterozygous FH (HeFH), and to examine the associations between dietary quality and biomarkers related to cardiovascular disease in adults with HeFH.

Methods

We included 205 adults (≥18 years) with HeFH who received follow-up at the Lipid Clinic in Oslo and compared them to controls (n = 228). Dietary intake was assessed using a food frequency questionnaire and dietary quality was assessed using the HNFI. Blood samples were analysed for levels of blood lipids, plasma fatty acids (FAs), and markers of inflammation and platelet activation.

Results

The HeFH patients (median 60 years; 50.2 % female; 25.9 % in secondary prevention) had lower intake of total and saturated fat compared to controls (32.6 energy percent (E%) vs. 34.9 E%, and 9.6 E% vs 12.0 E%, respectively; p < 0.001 for both). In the HeFH patients, increasing dietary quality was associated with increased plasma levels of the n-3 polyunsaturated FAs (PUFAs) eicosapentaenoic acid and docosahexaenoic acid, and the n-6 PUFA linoleic acid, and lower plasma levels of the inflammatory cytokines Tumor Necrosis Factor and interleukin-6, and of the platelet-derived inflammatory cytokines Platelet Factor 4 and Neutrophil-Activating Peptide-2.

Conclusion

Norwegian patients with HeFH followed up at a Lipid Clinic eat healthier than controls. Adherence to a healthy dietary pattern is associated with higher plasma levels of n-3 and n-6 PUFA, and lower levels of inflammatory markers, including platelet markers. This may suggest that adherence to an overall healthy dietary pattern might be beneficial for HeFH patients independent of the cholesterol-lowering effect of the diet.

Coronary artery event-free or resilient familial hypercholesterolemia: what's in a name?

PURPOSE OF REVIEW

Familial hypercholesterolemia (FH) is an autosomal semi-dominant condition, characterized by excessive circulating low-density lipoprotein cholesterol (LDL-C) from birth that substantially accelerates the onset and progression of atherosclerotic cardiovascular disease (ASCVD), classically coronary artery disease (CAD). Elevated plasma LDL-C integrated over time is unequivocally the major determinant of ASCVD in heterozygous FH (HeFH); however, the wide variation in incidence and progression of ASCVD suggests a role for a wide spectrum of risk modifiers. We reviewed recent evidence describing the features of an ASCVD-free entity referred to as resilient FH among patients with HeFH.

RECENT FINDINGS

Compared with nonresilient FH patients, resilient patients are more likely to be female, and have a lower prevalence of ASCVD comorbidities, higher levels of HDL-C and larger HDL particles, as well as a lower level of lipoprotein(a). A lower SAFEHEART risk score is also an independent predictor of resilient FH. Gene expression studies also demonstrate that resilient FH patients are associated with a less atherogenic gene expression profile in relation to HDL metabolism and immune responses, as reflected by higher expression of ABCA1 and ABCG1, and lower expression of STAT2 and STAT3, respectively.

SUMMARY

A group of HeFH patients, referred as resilient FH, can survive to advance ages without experiencing any ASCVD events. Several key contributors to the event-fee CAD in HeFH patients have been identified. This could not only improve risk stratification and management for FH but also be of major importance for the general population in primary and secondary prevention. However, resilient FH remains an under-investigated area and requires further research.

Obesity and atherosclerotic cardiovascular disease in adults with heterozygous familial hypercholesterolemia: An analysis from HELLAS-FH registry

BACKGROUND

Familial hypercholesterolemia (FH) and obesity are well-established risk factors of atherosclerotic cardiovascular disease (ASCVD). Despite high prevalence, their joint association with ASCVD remains largely unknown.

OBJECTIVE

To investigate the association of obesity with prevalent ASCVD in individuals with heterozygous FH (HeFH) enrolled in the Hellenic Familial Hypercholesterolemia Registry (HELLAS-FH).

METHODS

FH diagnosis was based on Dutch Lipid Clinic Network (DLCN) criteria. Adults with at least possible FH diagnosis (DLCN score ≥3) and available body mass index (BMI) values were included. Homozygous FH individuals were excluded.

RESULTS

1655 HeFH adults (mean age 51.0 ± 14.4 years, 48.6% female) were included; 378 (22.8%) and 430 (26.0%) were diagnosed with probable and definite FH, respectively. Furthermore, 371 participants (22.4%) had obesity and 761 (46.0%) were overweight. Prevalence of ASCVD risk factors increased progressively with BMI. Prevalence of coronary artery disease (CAD) was 23.4% (3.2% for stroke and 2.7% for peripheral artery disease [PAD]), and increased progressively across BMI groups. After adjusting for traditional ASCVD risk factors and lipid-lowering medication, individuals with obesity had higher odds of established CAD (OR: 1.54, 95% CI: 1.04-2.27, p = 0.036) as well as premature CAD (OR: 1.74, 95% CI: 1.17-2.60, p = 0.009) compared with those with normal BMI. No association was found with stroke or PAD.

CONCLUSIONS

Over half of adults with HeFH have overweight or obesity. Obesity was independently associated with increased prevalence of CAD in this population.

Gene expression profiling in elderly patients with familial hypercholesterolemia with and without coronary heart disease

BACKGROUND AND AIMS

Elderly familial hypercholesterolemia (FH) patients are at high risk of coronary heart disease (CHD) due to high cholesterol burden and late onset of effective cholesterol-lowering therapies. A subset of these individuals remains free from any CHD event, indicating the potential presence of protective factors. Identifying possible cardioprotective gene expression profiles could contribute to our understanding of CHD prevention and future preventive treatment. Therefore, this study aimed to investigate gene expression profiles in elderly event-free FH patients.

METHODS

Expression of 773 genes was analysed using the Nanostring Metabolic Pathways Panel, in peripheral blood mononuclear cells (PBMCs) from FH patients ≥65 years without CHD (FH event-free, n = 44) and with CHD (FH CHD, n = 39), and from healthy controls ≥70 years (n = 39).

RESULTS

None of the genes were differentially expressed between FH patients with and without CHD after adjusting for multiple testing. However, at nominal p < 0.05, we found 36 (5%) differentially expressed genes (DEGs) between the two FH groups, mainly related to lipid metabolism (e.g. higher expression of ABCA1 and ABCG1 in FH event-free) and immune responses (e.g. lower expression of STAT1 and STAT3 in FH event-free). When comparing FH patients to controls, the event-free group had fewer DEGs than the CHD group; 147 (19%) and 219 (28%) DEGs, respectively.

CONCLUSIONS

Elderly event-free FH patients displayed a different PBMC gene expression profile compared to FH patients with CHD. Differences in gene expression compared to healthy controls were more pronounced in the CHD group, indicating a less atherogenic gene expression profile in event-free individuals. Overall, identification of cardioprotective factors could lead to future therapeutic targets.

Resilient Older Subjects with Heterozygous Familial Hypercholesterolemia, Baseline Differences and Associated Factors

Despite elevated low-density lipoprotein (LDL) cholesterol levels, some older subjects with heterozygous familial hypercholesterolemia (HeFH) do not develop atherosclerotic cardiovascular disease (ACVD) during their lifetime. The factors related to this resilient state have not been fully established. The aim of this study was to evaluate differential characteristics between older HeFH subjects with and without ACVD and factors associated with the presence of ACVD. Subjects were part of the Spanish Atherosclerosis Society Dyslipidemia Registry, and those ≥ 70 years old and with HeFH were included. Baseline characteristics of these subjects with and without ACVD were compared. A multivariate analysis was performed to assess factors associated with the presence of ACVD. A total of 2148 subjects with HeFH were included. Resilient subjects were mostly female, younger and presented fewer comorbidities with respect to the ACVD group. Subjects without ACVD had higher baseline high-density lipoprotein (HDL) cholesterol (55.8 ± 17.1 vs. 47.9 ± 15.4 mg/dL; p < 0.001) and lower lipoprotein(a) [Lp(a)] (53.4 ± 67.9 vs. 66.6 ± 85.6 mg/dL; p < 0.001) levels with respect to those in the ACVD group. Lp(a) and the presence of ≥3 risk factors were associated with the presence of ACVD.

Sphingosine 1-Phosphate and Apolipoprotein M Levels and Their Correlations with Inflammatory Biomarkers in Patients with Untreated Familial Hypercholesterolemia

High-density lipoprotein (HDL)-bound apolipoprotein M/sphingosine 1-phosphate (ApoM/S1P) complex in cardiovascular diseases serves as a bridge between HDL and endothelial cells, maintaining a healthy endothelial barrier. To date, S1P and ApoM in patients with untreated heterozygous familial hypercholesterolemia (HeFH) have not been extensively studied. Eighty-one untreated patients with HeFH and 32 healthy control subjects were included in this study. Serum S1P, ApoM, sCD40L, sICAM-1, sVCAM-1, oxLDL, and TNFα concentrations were determined by ELISA. PON1 activities were measured spectrophotometrically. Lipoprotein subfractions were detected by Lipoprint. We diagnosed FH using the Dutch Lipid Clinic Network criteria. Significantly higher serum S1P and ApoM levels were found in HeFH patients compared to controls. S1P negatively correlated with large HDL and positively with small HDL subfractions in HeFH patients and the whole study population. S1P showed significant positive correlations with sCD40L and MMP-9 levels and PON1 arylesterase activity, while we found significant negative correlation between sVCAM-1 and S1P in HeFH patients. A backward stepwise multiple regression analysis showed that the best predictors of serum S1P were large HDL subfraction and arylesterase activity. Higher S1P and ApoM levels and their correlations with HDL subfractions and inflammatory markers in HeFH patients implied their possible role in endothelial protection.