The impact of the COVID-19 pandemic in diabetes and dyslipidemia management in a Spanish region: a retrospective study of the Aragon population

Introduction

Previous research has indicated that the COVID-19 outbreak had a negative impact on the diagnosis and management of cardiometabolic diseases. Our aim was to analyze the impact of the COVID-19 pandemic on the management of dyslipidemia and type 2 diabetes (T2D) in the Aragon region of Spain.

Methods

We conducted an observational retrospective study, which included data from all patients diagnosed with active T2D or dyslipidemia in Aragon during 2019-2021. Data was collected from the BIGAN platform, a big database that includes all healthcare data from the Aragon population. Clinical, biochemical, and pharmacological prescription information was obtained for each patient and for each year.

Results

Out of the total population of 1,330,000 in the Aragon region, 90,000 subjects were diagnosed with T2D each year, resulting in a prevalence of approximately 7%. The COVID-19 pandemic resulted in a decrease in the prevalence of this disease and a lower incidence during the year 2020. In addition, patients with T2D experienced a deterioration of their glucose profile, which led to an increase in the number of patients requiring pharmacological therapy. The prevalence of dyslipidemia was approximately 23.5% in both 2019 and 2020 and increased to 24.5% in 2021. Despite the worsening of the anthropometric profile, the lipid profile improved significantly throughout 2020 and 2021 compared to 2019. Moreover, the number of active pharmacological prescriptions increased significantly in 2021.

Discussion

Our findings suggest that the overload of the health system caused by the COVID-19 pandemic has resulted in an underdiagnosis of T2D. Moreover, patients with T2D experienced a worsening of their glycemic profile, an increase in their pharmacological requirements, and lower performance of their analytical determinations. Dyslipidemic subjects improved their lipid profile although the value of lipid profile determination decreased between 2020 and 2021.

Triglyceride Metabolism Modifies Lipoprotein(a) Plasma Concentration

BACKGROUND

Lipoprotein(a) (Lp(a)) is a significant cardiovascular risk factor. Knowing the mechanisms that regulate its concentration can facilitate the development of Lp(a)-lowering drugs. This study analyzes the relationship between triglycerides (TGs) and Lp(a) concentrations, cross-sectionally and longitudinally, and the influence of the number and composition of TG-rich lipoproteins, and the APOE genotype.

METHODS

Data from Aragon Workers Health Study (AWHS) (n = 5467), National Health and Nutrition Examination Survey III phase 2 (n = 3860), and Hospital Universitario Miguel Servet (HUMS) (n = 2079) were used for cross-sectional TG and Lp(a) relationship. Lp(a) intrasubject variation was studied in AWHS participants and HUMS patients with repeated measurements. TG-rich lipoproteins were quantified by nuclear magnetic resonance in a subsample from AWHS. Apolipoproteins B and E were quantified by Luminex in very low-density lipoprotein (VLDL) isolated by ultracentrifugation, from HUMS samples. APOE genotyping was carried in AWHS and HUMS participants. Regression models adjusted for age and sex were used to study the association.

RESULTS

The 3 studies showed an inverse relationship between TG and Lp(a). Increased VLDL number, size, and TG content were associated with significantly lower Lp(a). There was an inverse association between the apoE concentration in VLDL and Lp(a). No significant association was observed for apolipoprotein (apo)B. Subjects carrying the apoE2/E2 genotype had significantly lower levels of Lp(a).

CONCLUSION

Our results show an inverse relationship Lp(a)-TG. Subjects with larger VLDL size have lower Lp(a), and lower values of Lp(a) were present in patients with apoE-rich VLDL and apoE2/E2 subjects. Our results suggest that bigger VLDLs and VLDLs enriched in apoE are inversely involved in Lp(a) plasma concentration.

Diet quality in association to lipidaemic profile in adults of families at high-risk for type 2 diabetes in Europe: The Feel4Diabetes study

BACKGROUND AND AIMS

The role of diet in blood lipids is scarcely investigated in adults at risk of Type 2 Diabetes Mellitus (T2DM) and even less studied regarding their socioeconomic status (SES). This study aimed to investigate the associations of diet quality with blood lipids in adults from families at high-risk for developing T2DM from six European countries, considering their SES.

METHODS AND RESULTS

In total 2049 adults (67% women) from relatively low-SES regions and high T2DM risk families were enrolled. Dietary habits, sedentary behaviour and sociodemographic characteristics were assessed using standardised questionnaires. The associations of tertiles of healthy diet score (HDS) with blood lipids were tested by univariate analysis of variance (UNIANOVA). HDL-Cholesterol (HDL-C) was positively (B 1.54 95%CI 0.08 to 2.99) and LDL-Cholesterol (LDL-C) (B -4.15 95%CI -7.82 to -0.48), ratio of total cholesterol to HDL-C (B -0.24 95%CI -0.37 to -0.10), ratio of LDL-C to HDL-C (B -0.18 95%CI -0.28 to -0.08) and Atherogenic Index of Plasma (B -0.03 95%CI -0.06 to 0.00) inversely associated with the highest tertile of diet score compared to the lowest tertile independently of age, sex, Body Mass Index, total screen time and smoking. In sub-analysis of education (<14 and ≥ 14 years of education), these findings were only significant in the high-SES group.

CONCLUSION

While diet quality was poorer in the low-SES group, an association between diet quality and lipidemic profile was not found, as increased central obesity and smoking prevalence might have confounded this association. These findings indicate the need for tailor-made interventions, guided by the specific risk factors identified per population sub groups.

Effect of the Consumption of Alcohol-Free Beers with Different Carbohydrate Composition on Postprandial Metabolic Response

Background: We investigated the postprandial effects of an alcohol-free beer with modified carbohydrate (CH) composition compared to regular alcohol-free beer. Methods: Two randomized crossover studies were conducted. In the first study, 10 healthy volunteers received 25 g of CH in four different periods, coming from regular alcohol-free beer (RB), alcohol-free beer enriched with isomaltulose and a resistant maltodextrin (IMB), alcohol-free beer enriched with resistant maltodextrin (MB), and a glucose-based beverage. In the second study, 20 healthy volunteers were provided with 50 g of CH from white bread (WB) plus water, or with 14.3 g of CH coming from RB, IMB, MB, and extra WB. Blood was sampled after ingestion every 15 min for 2 h. Glucose, insulin, incretin hormones, TG, and NEFAs were determined in all samples. Results: The increase in glucose, insulin, and incretin hormones after the consumption of IMB and MB was significantly lower than after RB. The consumption of WB with IMB and MB showed significantly less increase in glucose levels than WB with water or WB with RB. Conclusions: The consumption of an alcohol-free beer with modified CH composition led to a better postprandial response compared to a conventional alcohol-free beer.

Glycerol kinase deficiency in adults: Description of 4 novel cases, systematic review and development of a clinical diagnostic score

BACKGROUND AND AIMS

Glycerol kinase deficiency (GKD) is a rare genetic disorder characterized by hyperglycerolemia and glyceroluria, which could be misdiagnosed as a moderate to severe hypertriglyceridemia (HTG). We aimed to describe four novel cases of GKD, to complete a systematic review of all cases of isolated GKD published so far, and to develop a suspicion clinical diagnostic score for GKD.

METHODS

We reported four cases with suspicion of GKD and compared their phenotype with 584 males with triglycerides (TG) > 300 mg/dL, selected as control group (HTG non-GKD). The GK gene was sequenced in all cases. Lipoprotein particle concentrations were measured in all cases with GKD. The systematic review involved a PubMed, Cochrane and Scopus databases search to identify anthropometric and biochemical characteristics of all described cases with GKD.

RESULTS

The systematic review retrieved a total of 15 articles involving 39 subjects with GKD. GKD cases reported a history of high TG levels resistant to lipid-lowering therapy. Compared to GKD subjects (n = 43), HTG non-GKD subjects (n = 584) showed significantly higher BMI, total cholesterol, non-HDL cholesterol and gamma-glutamyltransferase, significantly lower HDL cholesterol and TG, and higher prevalence of diabetes. The proposed diagnostic score was significantly higher in GKD than in HTG non-GKD subjects.

CONCLUSIONS

This is the first systematic review that compiles all GKD cases reported to date including 4 novel cases, and examine the differential GKD phenotype compared to other types of HTG. The proposed score would have a broad utility in clinical practice to avoid unwarranted lipid lowering treatment in GKD patients.

Impaired Sensitivity to Thyroid Hormones Is Associated With Diabetes and Metabolic Syndrome

OBJECTIVE

Diabetes prevalence and incidence increase among individuals with hypothyroidism but also among those with hyperthyroxinemia, which seems contradictory. Both high free thyroxine (fT4) and high thyroid-stimulating hormone (TSH) are present in the resistance to thyroid hormone syndrome. A mild acquired resistance to thyroid hormone might occur in the general population and be associated with diabetes. We aimed to analyze the association of resistance to thyroid hormone indices (the Thyroid Feedback Quantile-based Index [TFQI], proposed in this work, and the previously used Thyrotroph T4 Resistance Index and TSH Index) with diabetes.

RESEARCH DESIGN AND METHODS

We calculated the aforementioned resistance to thyroid hormone indices based on a U.S. representative sample of 5,129 individuals ≥20 years of age participating in the 2007-2008 National Health and Nutrition Examination Survey (NHANES). Also, to approximate TFQI, a U.S.-referenced Parametric TFQI (PTFQI) can be calculated with the spreadsheet formula =NORM.DIST(fT4_cell_in_pmol_per_L,10.075,2.155,TRUE)+NORM.DIST(LN(TSH_cell_in_mIU_per_L),0.4654,0.7744,TRUE)-1. Outcomes of interest were glycohemoglobin ≥6.5%, diabetes medication, diabetes-related deaths (diabetes as contributing cause of death), and additionally, in a fasting subsample, diabetes and metabolic syndrome. Logistic and Poisson regressions were adjusted for sex, age, and race/ethnicity.

RESULTS

Odd ratios for the fourth versus the first quartile of TFQI were 1.73 (95% CI 1.32, 2.27) (P _trend = 0.002) for positive glycohemoglobin and 1.66 (95% CI 1.31, 2.10) (P _trend = 0.001) for medication. Diabetes-related death rate ratio for TFQI being above versus below the median was 4.81 (95% CI 1.01, 22.94) (P _trend = 0.015). Further adjustment for BMI and restriction to normothyroid individuals yielded similar results. Per 1 SD in TFQI, odds increased 1.13 (95% CI 1.02, 1.25) for diabetes and 1.16 (95% CI 1.02, 1.31) for metabolic syndrome. The other resistance to thyroid hormone indices showed similar associations for diabetes-related deaths and metabolic syndrome.

CONCLUSIONS

Higher values in resistance to thyroid hormone indices are associated with obesity, metabolic syndrome, diabetes, and diabetes-related mortality. Resistance to thyroid hormone may reflect energy balance problems driving type 2 diabetes. These indices may facilitate monitoring treatments focused on energy balance.

Different protein composition of low-calorie diet differently impacts adipokine profile irrespective of weight loss in overweight and obese women

BACKGROUND AND AIMS

High-protein (HP) diets have shown benefits in cardiometabolic markers such as insulin or triglycerides but the responsible mechanisms are not known. We aimed to assess the effect of three energy-restricted diets with different protein contents (20%, 27%, and 35%; ∼80% coming from animal source) on plasma adipokine concentration and its association with changes in cardiometabolic markers.

METHODS

Seventy-six women (BMI 32.8 ± 2.93) were randomized to one of three calorie-reduced diets, with protein, 20%, 27%, or 35%; carbohydrates, 50%, 43%, or 35%; and fat, 30%, for 3 months. Plasma adipokine (leptin, resistin, adiponectin, and retinol-binding protein 4; RBP4) levels were assessed.

RESULTS

After 3 months, leptin concentration decreased in all groups without differences among them, while resistin levels remained unchanged. Adiponectin concentration heterogeneously changed in all groups (P for trend = 0.165) and resistin concentration did not significantly change. RPB4 significantly decreased by -17.5% (-31.7, -3.22) in 35%-protein diet (P for trend = 0.024 among diets). Triglycerides improved in women following the 35%-protein diet regardless of weight loss; RBP4 variation significantly influenced triglyceride concentration change by 24.9% and 25.9% when comparing 27%- and 35%- with 20%-protein diet, respectively.

CONCLUSIONS

A 35%-protein diet induced a decrease in RBP4 regardless of weight loss, which was directly associated with triglyceride concentration improvement. These findings suggest that HP diets improve the cardiometabolic profile, at least in part, through changes in adipokine secretion. Whether this beneficial effect of HP diet is due to improvements in hepatic or adipose tissue functionality should be elucidated.

CLINICAL TRIAL REGISTRATION

The clinical trial has been registered in ClinicalTrials.gov (Identifier: NCT02160496).

Bile acid synthesis precursors in subjects with genetic hypercholesterolemia negative for LDLR/APOB/PCSK9/APOE mutations. Association with lipids and carotid atherosclerosis

Some oxysterols are precursors of bile acid synthesis and play an important role in cholesterol homeostasis. However, if they are involved in the pathogeny of genetic hypercholesterolemia has not been previously explored. We have studied non-cholesterol sterol markers of cholesterol synthesis (lanosterol and desmosterol) and oxysterols (7α-hydroxy-4-cholesten-3-one, 24S-hydroxycholesterol and 27-hydroxycholesterol) in 200 affected subjects with primary hypercholesterolemia of genetic origin, negative for mutations in LDLR, APOB, PCSK9 and APOE genes (non-FH GH) and 100 normolipemic controls. All studied oxysterols and cholesterol synthesis markers were significantly higher in affected subjects than controls (P<0.001). Ratios of oxysterols to total cholesterol were higher in non-FH GH than in controls, although only 24S-hydroxycholesterol showed statistical significance (P<0.001). Cholesterol synthesis markers had a positive correlation with BMI, triglycerides, cholesterol and apoB in control population. However, these correlations disappeared in non-FH GH with the exception of a weak positive correlation for non-HDL cholesterol and apoB. The same pattern was observed for oxysterols with high positive correlation in controls and absence of correlation for non-FH GH, except non-HDL cholesterol for 24S-hydroxycholesterol and 27-hydroxycholesterol and apoB for 27-hydroxycholesterol. All non-cholesterol sterols had positive correlation among them in patients and in controls. A total of 65 (32.5%) and 35 (17.5%) affected subjects presented values of oxysterols ratios to total cholesterol above the 95th percentile of the normal distribution (24S-hydroxycholesterol and 27-hydroxycholesterol, respectively). Those patients with the highest levels of 24S-hydroxycholesterol associated an increase in the carotid intima media thickness. These results suggest that bile acid metabolism is affected in some patients with primary hypercholesterolemia of genetic origin, negative for mutations in the candidate genes, and may confer a higher cardiovascular risk. Our results confirm that cholesterol synthesis overproduction is a primary defect in non-HF GH and suggest that subjects with non-FH GH show high levels of oxysterols in response to hepatic overproduction of cholesterol.

Lipid phenotype and heritage pattern in families with genetic hypercholesterolemia not related to LDLR, APOB, PCSK9, or APOE

BACKGROUND

A substantial proportion of individuals clinically diagnosed as familial hypercholesterolemia (FH) do not carry pathogenic mutations in candidate genes. Whether in them the high cholesterol trait is transmitted monogenically has not been studied.

OBJECTIVES

We assessed the inheritance pattern, penetrance, and expression of high low-density lipoprotein (LDL)-cholesterol (LDLc) in families with genetic hypercholesterolemia (GH) without known causative mutations (non-FH-GH).

METHODS

The study included probands with a clinical diagnosis of FH and their families attending 2 lipid clinics in Spain. Inclusion criteria for probands were LDLc >95th percentile, triglycerides <90th percentile, at least 1 first-degree family member with LDLc >90th percentile, >5 points in the Dutch Lipid Clinic Network criteria score, and absence of mutations in LDLR, APOB, PCSK9 or APOE. Eleven FH families with a LDLR mutation were also examined for comparison.

RESULTS

We analyzed 49 non-FH-GH probands and 277 first-and second-degree relatives. LDLc was >90th percentile in 37.8% of blood relatives, at concentrations similar to those of probands. LDLc had a normal distribution in non-FH-GH families, in contrast with a bimodal distribution in FH families. When a dominant model was tested, family-based association tests gave much lower heritability values for total cholesterol and LDLc in non-FH-GH (0.39 and 0.32, respectively) than in FH (0.78 and 0.61, respectively).

CONCLUSIONS

Non-FH-GH families have a milder lipid phenotype than genetically defined FH. The heritage pattern of LDLc in non-FH-GH does not fit with a monogenic disorder. Our findings support the concept that most non-FH-GHs are polygenic hypercholesterolemias.

Effect of different fat-enriched meats on non-cholesterol sterols and oxysterols as markers of cholesterol metabolism: Results of a randomized and cross-over clinical trial

BACKGROUND AND AIM

Different kinds of fatty acids can affect the synthesis, absorption, and elimination of cholesterol. This study was carried out to assess the associations of cholesterol metabolism with the intake of two meats with different fatty acid composition in healthy volunteers.

METHODS AND RESULTS

The study group was composed of 20 subjects (12 males and eight females; age, 34.4 ± 11.6 years; body mass index (BMI), 23.5 ± 2.3 kg/m(2); low-density lipoprotein (LDL) cholesterol, 2.97 ± 0.55 mmol/l; high-density lipoprotein (HDL) cholesterol, 1.61 ± 0.31 mmol/l; triglycerides (TG), 1.06 ± 0.41 mmol/l) who completed a 30-day randomized and cross-over study to compare the cholesterol metabolism effect of 250 g of low-fat lamb versus 250 g of high-fat lamb per day in their usual diet. Cholesterol absorption, synthesis, and elimination were estimated from the serum non-cholesterol sterol and oxysterol concentrations analyzed by a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). No changes in weight, plasma lipids, or physical activity were observed across the study. Cholesterol intestinal absorption was decreased with both diets. Cholesterol synthesis and elimination decreased during the low-fat lamb dietary intervention (ρ = 0.048 and ρ = 0.005, respectively).

CONCLUSION

Acute changes in the diet fat content modify the synthesis, absorption, and biliary elimination of cholesterol. These changes were observed even in the absence of total and LDL cholesterol changes in plasma.

REGISTRATION NUMBER FOR CLINICAL TRIALS

ClinicalTrials.gov PRS, NCT02259153.

Severe hypercholesterolemia and phytosterolemia with extensive xanthomas in primary biliary cirrhosis: role of biliary excretion on sterol homeostasis

Primary biliary cirrhosis (PBC) is an autoimmune, chronic, cholestatic liver disease that affects primarily women. PBC is commonly associated with hypercholesterolemia that has been associated with cholestasis. We report an exceptionally high blood cholesterol and phytosterols with just mild cholestasis indicating a selective defect in sterol biliary secretion in a patient with PBC.

A genetic variant in the LDLR promoter is responsible for part of the LDL-cholesterol variability in primary hypercholesterolemia

BACKGROUND

GWAS have consistently revealed that LDLR locus variability influences LDL-cholesterol in general population. Severe LDLR mutations are responsible for familial hypercholesterolemia (FH). However, most primary hypercholesterolemias are polygenic diseases. Although Cis-regulatory regions might be the cause of LDL-cholesterol variability; an extensive analysis of the LDLR distal promoter has not yet been performed. We hypothesized that genetic variants in this region are responsible for the LDLR association with LDL-cholesterol found in GWAS.

METHODS

Four-hundred seventy-seven unrelated subjects with polygenic hypercholesterolemia (PH) and without causative FH-mutations and 525 normolipemic subjects were selected. A 3103 pb from LDLR (-625 to +2468) was sequenced in 125 subjects with PH. All subjects were genotyped for 4 SNPs (rs17242346, rs17242739, rs17248720 and rs17249120) predicted to be potentially involved in transcription regulation by in silico analysis. EMSA and luciferase assays were carried out for the rs17248720 variant. Multivariable linear regression analysis using LDL-cholesterol levels as the dependent variable were done in order to find out the variables that were independently associated with LDL-cholesterol.

RESULTS

The sequencing of the 125 PH subjects did not show variants with minor allele frequency ≥ 10%. The T-allele from g.3131C > T (rs17248720) had frequencies of 9% (PH) and 16.4% (normolipemic), p < 0.00001. Studies of this variant with EMSA and luciferase assays showed a higher affinity for transcription factors and an increase of 2.5 times in LDLR transcriptional activity (T-allele vs C-allele). At multivariate analysis, this polymorphism with the lipoprotein(a) and age explained ≈ 10% of LDL-cholesterol variability.

CONCLUSION

Our results suggest that the T-allele at the g.3131 T > C SNP is associated with LDL-cholesterol levels, and explains part of the LDL-cholesterol variability. As a plausible cause, the T-allele produces an increase in LDLR transcriptional activity and lower LDL-cholesterol levels.

Carotid atherosclerosis and lipoprotein particle subclasses in familial hypercholesterolaemia and familial combined hyperlipidaemia

BACKGROUND AND AIMS

Familial hypercholesterolaemia (FH) and familial combined hyperlipidaemia (FCH) are common atherogenic disorders with great variability in cardiovascular disease (CVD). No direct atherosclerosis burden comparisons have been performed between FH and FCH in relation to lipoprotein particle distribution.

METHODS AND RESULTS

Risk factors and three measures of carotid intima-media thickness (IMT) in both sides were determined in 572 FH, 250 FCH and 200 controls. Lipoproteins were assessed by nuclear magnetic resonance (NMR) spectroscopy. Compared with controls, IMT measures were increased in FH and FCH. FCH had the highest adjusted mean-maximum IMT. FH had twice low-density lipoprotein (LDL) particles than controls, but similar LDL subclass size and distribution. FCH subjects also had increased LDL particles and the highest number of small LDL (1519 ± 731 nmol l(-1) vs. 887 ± 784 nmol l(-1) in FH and 545 ± 409 nmol l(-1) in controls). Age, gender, cholesterol/high-density lipoprotein (HDL) ratio, smoking and systolic blood pressure were independently associated with IMT in FH (r(2) = 0.38). The same variables, except cholesterol/HDL ratio, were associated with IMT in FCH (r(2) = 0.40). Among NMR lipoproteins, only VLDL and chylomicrons increased IMT prediction in FCH by 0.8%.

CONCLUSION

FH and FCH subjects show increased carotid atherosclerosis in relation to classical risk factors. Lipoprotein subclasses do not substantially contribute to IMT variability.

Age and sex influence the relationship between waist circumference and abdominal fat distribution measured by bioelectrical impedance

Waist circumference (WC) is a subrogate measurement of abdominal visceral fat (AVF) with a different normal threshold for men and women. However, age plays an important role in the relationship of WC with AVF. The hypothesis of the present work was that the adjustment of the WC, not only by sex but also by age, would improve WC prediction of AVF as measured by a new bioelectrical impedance (BIA) methodology. The study was carried out in 311 subjects (178 men and 133 women) with a body mass index between 18 and 35 kg/m(2). Abdominal fat composition was measured by BIA by using a new device recently developed specifically for the measurement of abdominal fat compartments (ViScan AB140;Omron Corp, Tokyo, Japan). Clinical, anthropometric, and biochemical data were also collected. There was a high correlation of WC with total abdominal fat and AVF in all age ranges and for both fat depots, which decreased with age in men but remained more stable in women. Age independently influenced the level of AVF in women and in those subjects with normal WC, increasing by 0.32 and 0.47 for each decade of age, respectively. In conclusion, age plays an important role in the association between WC and AVF with a high correlation existing in all age ranges. A specific BIA method that measures abdominal composition would be useful in women and in those subjects with normal WC as an indicator of AVF.

Effect of phlebotomy on lipid metabolism in subjects with hereditary hemochromatosis

Genetic predisposition to hereditary hemochromatosis (HH) is associated with primary hypertriglyceridemia (HTG). If iron overload influences the development of HTG, the management of these patients could be different. However, the metabolic syndrome in primary HTG is frequent; and it could partially confuse the association. The objective was to determine whether periodic bloodletting could decrease triglyceride concentrations in subjects with HH and iron overload. We retrospectively studied 155 genetically defined HH patients (C282Y homozygotes and compound heterozygotes C282Y/H63D) with iron overload and under periodic therapeutic phlebotomy. Hypertriglyceridemia (triglycerides ≥150 mg/dL) was present in 49 subjects at baseline (31.6%). Phlebotomies significantly decreased triglycerides, especially in subjects with basal HTG (from 287 mg/dL at baseline to 133 mg/dL after phlebotomies, P < .001). Blood glucose and total cholesterol did not change with phlebotomies. The triglyceride-lowering effect was obtained until ferritin concentration decreased to less than 200 μg/L and transferrin saturation to less than 40%. The triglyceride-lowering effect was obtained for glucose levels both less than and greater than 100 mg/dL. In summary, HH subjects frequently have HTG that improves after therapeutic phlebotomy, independently of basal blood glucose. Our results suggest that therapeutic phlebotomy could be a useful therapeutic approach in patients with HTG and iron overload.

Prevalence of metabolic syndrome and cardiovascular disease in a hypertriglyceridemic population

BACKGROUND

We aim to study the prevalence of metabolic syndrome (MS), hypertension and diabetes, and their relationship to cardiovascular disease in subjects with hypertriglyceridemia.

METHODS

This is an observational cross-sectional study, uncontrolled and multicentre study. Selected subjects were patients with hypertriglyceridemia (triglycerides, TG, ≥ 200 mg/dl) visited in the Lipid Units of the Spanish Arteriosclerosis Society who met the inclusion criteria. Prevalence of MS (ATPIII and IDF criteria, MS-ATPIII or MS-IDF), hypertension and diabetes were studied. The presence of cardiovascular disease (CVD) was also determined.

RESULTS

The results showed that individuals referred for hypertriglyceridemia had a high prevalence of MS-ATPIII 79.6% and MS-IDF 75.2%. The prevalence of MS was independent of plasma triglyceride levels. The prevalence of hypertension and diabetes were 50.9% and 33.5%, respectively. The prevalence of diabetes was double than in the general population. The prevalence of CVD was 14.6%. 95.9% of CVD events were found in patients with MS-ATPIII and only 4.1% in the group without MS-ATPIII, significant differences.

CONCLUSIONS

Hypertriglyceridemia is associated to the metabolic syndrome and diabetes, as well as the risk of CVD, independently of the levels of triglycerides. Hypertriglyceridemia may be an important marker in the screening of these severe metabolic and vascular abnormalities.

Inverse association between serum phospholipid oleic acid and insulin resistance in subjects with primary dyslipidaemia

BACKGROUND & AIMS

Data on intake of oleic acid (OA) and insulin resistance (IR) are inconsistent. We investigated whether OA in serum phosphatidylcholine relates to surrogate measures of IR in dyslipidaemic subjects from a Mediterranean population.

METHODS

Cross-sectional study of 361 non-diabetic subjects (205 men, 156 women; mean age 44 and 46 y, respectively; BMI 25.7 kg/m(2)). IR was diagnosed by BMI and HOMA values using published criteria validated against the euglycemic clamp. Alternatively, IR was defined by the 75th percentile of HOMA-IR of our study population. The fatty acid composition of serum phosphatidylcholine was determined by gas-chromatography.

RESULTS

The mean (±SD) proportion of OA was 11.7 ± 2.0%. Ninety-two subjects (25.5%) had IR. By adjusted logistic regression, including the proportions of other fatty acids known to relate to IR, the odds ratios (OR) (95% confidence intervals) for IR were 0.75 (0.62-0.92) for 1% increase in OA and 0.84 (0.71-0.99) for 1% increase in linoleic acid. Other fatty acids were unrelated to IR. When using the alternate definition of IR, OA remained a significant predictor (0.80 [0.65-0.99]).

CONCLUSIONS

Higher phospholipid proportions of OA relate to less IR, suggesting an added benefit of increasing olive oil intake within the Mediterranean diet.

High-density lipoprotein cholesterol increase and non-cardiovascular mortality: a meta-analysis

CONTEXT

Many observational prospective studies have confirmed the inverse relationship between high-density lipoprotein (HDL) cholesterol and coronary heart disease. However, the potential benefit of the pharmacological increase in HDL cholesterol has not been clearly demonstrated. Moreover, in some interventions an increase in total mortality has been reported.

OBJECTIVE

The objective of this meta-analysis was to determine the relationship between HDL cholesterol increase and non-cardiovascular mortality in randomised trials.

DATA SOURCES

Authors searched Medline up to December 2008.

STUDY SELECTION

Four reviewers identified randomised trials in which, through different types of interventions, HDL cholesterol increase in the treatment group was >4% compared to control group, both groups reported separately non-cardiovascular mortality and the duration of the study was, at least, one year.

DATA EXTRACTION

Data of HDL cholesterol concentrations and deaths were collected as they appeared in the original studies. If necessary, reviewers calculated data by using trial information.

RESULTS

Meta-regression analysis included 44 articles corresponding to 107 773 participants. Analysis showed an association between HDL cholesterol increase and non-cardiovascular mortality (p=0.023), however, the correlation disappeared when we excluded the ILLUMINATE (Investigation of Lipid Level Management to Understand its Impact in Atherosclerosis Events) trial from the analysis (p=0.972).

CONCLUSIONS

Meta-regression analysis results suggest that increases in HDL cholesterol up to 40% are not associated with higher non-cardiovascular death. The increase in adverse events observed in some trials where HDL cholesterol was raised in large amounts could be related with the drug mechanisms more than the HDL cholesterol increase itself.

Serum ferritin is a major determinant of lipid phenotype in familial combined hyperlipidemia and familial hypertriglyceridemia

Familial combined hyperlipidemia (FCH) and familial hypertriglyceridemia (FHTG) share pathogenic mechanisms and a high interaction with components of the metabolic syndrome. The metabolic syndrome associates increased serum ferritin concentration and high cardiovascular risk. The objective was to describe the frequency of iron overload and the relationship between serum ferritin and the phenotype in patients with FCH and FHTG. The study was composed of 211 consecutive unrelated patients aged at least 18 years with primary hypertriglyceridemia, 149 with FCH, and 62 with FHTG. The prevalence of the metabolic syndrome and hyperferritinemia was very high in both hypertriglyceridemic groups (51.7% and 20.1% in FCH and 62.9% and 16.1% in FHTG, respectively), without significant statistical differences between them. Serum ferritin concentration did not show any significant association with the number of metabolic syndrome criteria. Subjects in the highest tertile of ferritin concentration (ferritin >200 mug/L) presented higher concentrations of triglycerides and liver enzymes than subjects in the first tertile of ferritin concentration (ferritin <90 mug/L). The highest positive correlation coefficient for triglycerides was found with ferritin in FCH and in FHTG subjects (R = 0.317 [P < .001] when combined). Ferritin was also the covariate that showed the highest independent association with triglycerides in FCH and FHTG. In contrast, ferritin was not associated with carotid intima-media thickness. In summary, serum ferritin is commonly increased in FCH and in FHTG, it is not related with the presence of metabolic syndrome, and it is highly correlated with liver enzymes.