- Email: [email protected]
Gender reassignment and cardiovascular risk
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Abstracts / Atherosclerosis 236 (2014) e303ee309
THE IMPACT OF ROUTINE NEXT GENERATION SEQUENCING TESTING FOR FAMILIAL HYPERCHOLESTEROLAEMIA e 5 MONTHS SERVICE EXPERIENCE L. Yarram-Smith a, g, P. Dean a, g, S. O'Shea a, g, G. Dennis a, g, G. Bayly b,g, A. Taylor c, g, A. Day d, g, M. Watson e, g, P. Giles f, g, R. Ayling h, g, K. Haralambos h, g, S. Whatley h, g, I. McDowell h, g, M. Williams a, g a Bristol Genetics Laboratory, Bristol, United Kingdom; b Bristol Royal Infirmary, Bristol, United Kingdom; c Royal United Hospital, Bath, United Kingdom; d Weston General Hospital, Weston-super-Mare, United Kingdom; e Wessex Clinical Genetics Service, Princess Anne Hospital, Southampton, United Kingdom; f Manor Hospital, Moat Road, Walsall, United Kingdom; g Derriford Hospital, Plymouth, United Kingdom; h University Hospital of Wales, Cardiff, United Kingdom
NICE recommends comprehensive genetic testing in all patients clinically diagnosed with FH and genetic cascade testing of at-risk relatives, however, the cost of FH genetic testing still remains a barrier to commissioning. Bristol Genetics Laboratory (BGL) has developed a comprehensive, high throughput diagnostic genetic test for FH using next generation sequencing. The custom-designed targeted capture assay (HaloPlex, Agilent) sequences 4 FH genes; LDLR, PCSK9, APOB and LDLRAP1 and the SLCO1B1 variants (rs2306283 and rs4149056) associated with statininduced myopathy. A control gene is included to aid copy number (deletion/duplication) detection. Data analysis uses an open-source pipeline; alignment (bwa), variant calling (GATK), variant annotation (Geneticist Assistant, SoftGenetics), and copy number analysis (CONTRA/bespoke CNV tool). BGL has provided FH testing since 2008 and our patient cohort now exceeds 900. The NGS service was launched in October 2013, with parallel MLPA testing to further validate copy number detection. To date, 130 patients have been reported with 33 distinct mutations and a 30% (39/130) positive detection rate, the most common mutations being APOB c.10580G>A and LDLR c.313+1G>A. NGS copy number analysis successfully detected 5 LDLR deletions and generated a reportable copy number result in 71% of cases. MLPA will now be used as a reflex test where NGS data is equivocal, generating cost savings. A further 9% (12/130) of patients have variants of unknown significance (VUS) with 11 of these found in APOB. Comprehensive APOB screening was precluded prior to NGS due to the large size of the gene. Recent literature evidence and our service data suggest that there are clinically significant variants outside of the exon 26 hotspot region supporting a comprehensive screening approach. Current cost of NGS diagnostic testing is £250, which may reduce further with increased throughput. We report on our service experience, and future prospects illustrated by interesting case studies. GENETIC VARIANTS OF UNCERTAIN SIGNIFICANCE (VUS) IN FAMILIAL HYPERCHOLESTEROLAEMIA (FH): CAN FAMILY BASED ASSOCIATION STUDIES HELP DETERMINE PATHOGENICITY? K. Haralambos a, *, S.D. Whatley b, R. Edwards c, R. Gingell c, Townsend c, P. Holmans a, A. Clarke a, B.N. Datta b, I.F.W. McDowell b
D.
a Cardiff University, Cardiff, UK; b University Hospital of Wales, Cardiff and Vale Health Board, Cardiff, UK; c All Wales FH Cascade Testing Service, All Wales Medical Genetics Service, Cardiff, UK
* Corresponding author.
genetic association statistical analysis can be used to quantify the likelihood of pathogenicity based on the family relationship, number of subjects, and LDL-C (with adjustment for age and gender), allowing for the genetic relatedness between family members. Data from families who share the same VUS can be combined. Data from 51 family members with 11 different variants has been collected to date, concentrating first on those with more extensive families available for testing. All available members have been tested in three families, with each family having a different VUS in the LDLR gene. Analysis showed the VUS to be significantly associated with LDL-C in two families (c.2087G>A p¼0.007) (c.1073G>A; p¼0.002), but not in the other (c.2098G>A; p¼0.14) indicating that in two families the variant is likely to be pathogenic whereas in the third it is not. This study demonstrates the feasibility and value of a quantitative statistical approach to family studies compared to qualitative segregation studies which do not take into account the concentration of LDL-C. This approach provides useful additional evidence for the genetic diagnostic laboratory which can be shared with other centres using anonymous genetic data bases for FH. The information helps clinicians provide more clarity for their patients and families. THE IMPORTANCE OF CONSIDERING LOW-DENSITY LIPOPROTEIN CHOLESTEROL RESPONSE AS WELL AS CARDIOVASCULAR RISK IN DECIDING WHO CAN BENEFIT FROM STATIN THERAPY. Handrean Soran a, b, Paul Durrington b a
Cardiovascular Trials Unit, Central Manchester University Hospital NHS Foundation Trust, Manchester, UK; b Cardiovascular Research Group, University of Manchester, Manchester, UK Introduction: Statins are in many countries the most frequently prescribed class of medication. In clinical trials statins achieved a mean reduction in low density lipoprotein cholesterol (LDL-C) of 1.07mmol/l and decreased atherosclerotic cardiovascular disease (CVD) incidence by 24% relative to placebo. Guidelines seeking to deploy statin treatment optimally rely heavily on the use of estimates of absolute CVD risk as an arbiter of who should receive statins. Aim: To demonstrate that this is not an effective strategy unless the LDL cholesterol response to statin treatment, which is determined by the choice of statin, its dose and the pre-treatment LDL cholesterol level, is taken into account. Method: The formula for calculating NNT to prevent one CVD event with statin therapy, taking into account the decrease in LDL cholesterol achieved, is derived as follows:Events prevented per 100 people (ε) ¼ Absolute CVD risk* x LDL cholesterol decrease** x 0.22 NNT ¼ 100 ÷ ε NNT ¼ 100 ÷ (absolute CVD risk x LDL cholesterol decrease x 0.22) *% over next 10 years. s**mmol/l. Results: We show that this is easily achieved and can be integrated to cardiovascular risk software. Application of this evidence reveals that many people with high LDL cholesterol levels can benefit more than people currently receiving statin treatment solely on the basis of their absolute CVD risk, whereas others at higher CVD risk, but with lower LDL cholesterol, will derive little benefit. Conclusion: Taking pre-treatment LDL cholesterol, absolute risk and number need to treat in consideration when deciding who should receive statin therapy will lead to a better patient selection. GENDER REASSIGNMENT AND CARDIOVASCULAR RISK Nandini Rao*, Darren Harvey, Anjly Jain, Devaki Nair
Genetic testing of 1191 index patients from lipid clinics in the Wales FH service revealed a pathogenic mutation in 23% and a genetic variant of uncertain significance (VUS) in 8% (102 individuals, 67 variants). A VUS is a DNA sequence variant for which there is insufficient laboratory or clinical evidence to designate the variant as causative or not. Finding a VUS leaves the diagnosis uncertain for patients and cannot be used for family cascade testing. In this study family members are tested for LDL-cholesterol and VUS with the aim of assessing whether the variant tracks with LDL-C. Specialist
Dept of Clinical Biochemistry, Royal Free London NHS Foundation Trust, NW3 2QG, UK
* Corresponding author. Background: Gender reassignment involves psychological, hormonal and surgical interventions to achieve transition to the opposite gender.
Abstracts / Atherosclerosis 236 (2014) e303ee309
Cardiovascular disease (CVD) outcomes in these individuals using sex steroids are sparse and limited. Objective: We describe two patients referred to our Metabolic Lipid clinic for CVD risk assessment and review the literature. Description EW is a 78 y old male-to- female (MF) non-smoker, without family history of premature CVD, on ethinyl oestradiol 50mg patches and warfarin daily. Body mass index (BMI)25.83; waist circumference (WC) 80cm; and BP 146/72mmHg. TC: HDL 6, Lp(a) 0.85g/L, triglycerides 1.2mmol/L and calculated CVD risk is high. IR is a 47 y old, female-to- male (FM) non-smoker with a strong family history of premature CVD, awaiting testosterone therapy. BMI 21.59, WC 78cm and BP 124/78mmHg. TC: HDL 1.94, triglycerides 0.6mmol/L, and calculated CVD risk is low. CIMT e normal. Secondary causes of dyslipidaemia are excluded in both. EW is now on Pravastatin 10mg daily. IR’s CVD risk is being assessed with LpPLA2, Lp (a), and a gene score test to assess gene variants associated with CVD. The family is being tested for LDL mutations related to Familial Hyperlipidemia. Discussion: A European mortality study showed that in MF, ethinyl oestradiol use was linked to a threefold increased risk of death associated with CVD, independent of other risk factors. FM patients did not show this increased risk. A systematic review and meta-analyses on CVD outcomes was inconclusive but suggests that cross hormone therapies increase serum triglycerides in both groups. However, a trivial effect on HDL and systolic BP was noted in FM. Moreover, the relationship between androgens and CVD risk is complicated as endogenous and exogenous testosterone can be metabolised to oestrogens. Also, in European men, Y chromosome can be associated with CVD risk possibly through interactions with immunity and inflammation. THE CLINICAL AND LIFESTYLE DETERMINANTS OF SERUM HDL-C, APOLIPOPROTEIN A-1, PARAOXONASE-1 ACTIVITY AND OXIDISED LDL IN HEALTHY, MEDICATION NAÏVE MIDDLE-AGED ADULTS J.P. Hobkirk a, H. Soran b, d, M.G. Mellis c, P. Pemberton b, d, S. Carroll e a Hull York Medical School, University of Hull, Hull, UK; b Department of Cardiovascular Sciences, University of Manchester, UK; c Carnegie Research Institute, Leeds Metropolitan University, Leeds, UK; d Clinical Biochemistry, Manchester Royal Infirmary, Manchester, UK; e Department of Sport, Health and Exercise Science, University of Hull, Hull, UK
Introduction: HDL cholesterol may underestimate the anti-oxidative potential of HDL. HDL anti-oxidative potential is mediated by PON-1, which metabolises lipid peroxides and impacts on oxidised LDL (ox-LDL) concentrations. We sought to investigate the determinants of HDL-c, apo A-I and PON-1 activity and to ascertain whether HDL-c, apo A-I, PON-1 activity could explain the variance of ox-LDL concentrations in a sub-group of high PON-1 activity (n¼22) >230 or low (n¼22) <63 nmol/min/ml participants. Methods: 221 (72% male) participants were assessed during health assessments at Nuffield Health Medical Centre in Manchester. Participants avoided vigorous physical activity and alcohol 24 hours prior to assessment. Lifestyle factors including smoking status, alcohol intake and physical activity and cardio-respiratory fitness were assesssed. Participants with CVD or T2D were excluded. Fasting blood was taken to measure HDL-c, PON-1 activity, apo AI and ox-LDL and other blood variables. Correlations and regression analysis assessed inter-relationships and determinants of HDL-c, apo A-1, PON-1 activity and ox-LDL. Regression models included age, sex, waist, TG, alcohol, physical activity, fitness, hsCRP and QRISK. Results: The correlation between PON-1 activity and HDL-c (r¼0.12), apo AI (r¼0.11) were non-significant. Waist circumference, TG, alcohol intake, sex and fitness were predictors of HDL-c, accounting for 40.3% of the variance. Waist circumference, TG and alcohol predicted apo A-I concentrations, accounting for 13.1% of the variance. None of the variables measured predicted PON-1 activity. Ox-LDL was not significantly correlated with HDL-c (r¼0-.19) apo A-I (r¼-0.20) or PON-1 activity (r¼0.09) but was to TG (r¼0.69, p<0.001). Furthermore, TG (52%), hs-CRP (7.4%) and age (6.6%) accounted for 66% of the variance in ox-LDL. Discussion: PON-1 activity did not correlate with any clinical or lifestyle variables. Concentrations of ox-LDL were strongly related to TG
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concentrations. Lifestyle factors that regulate TG metabolism are an important therapy to decrease highly atherogenic ox-LDL particles. IMPAIRMENT OF HIGH DENSITY LIPOPROTEIN RESISTANCE TO LIPID PEROXIDATION AND ADIPOSE TISSUE INFLAMMATION IN OBESITY COMPLICATED BY OBSTRUCTIVE SLEEP APNEA Rahul Yadav a, b, *, Michael France a, b, Salam Hama a, Yifen Liu a, See Kwok b, Phil Pemberton c, Paul Durrington a, Maria Jeziorska a, Handrean Soran a, b a Cardiovascular Research Group, Core Technologies Facility, University of Manchester, UK; b Cardiovascular Trials Unit, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK; c Department of Biochemistry, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK
* Corresponding author. Abstract Context: Obstructive sleep apnea (OSA) complicates morbid obesity and is associated with increased cardiovascular disease incidence. An increase in circulating markers of chronic inflammation and dysfunctional high density lipoprotein (HDL) occur in severe obesity. Objective: To establish whether the effects of obesity on inflammation and HDL dysfunction are more marked when complicated by OSA. Design and patients: Morbidly obese patients (n¼41) were divided into those whose apnea-hypo-apnea index (AHI) was more or less than the median value and on the presence of OSA (“OSA” and “no OSA (nOSA)” groups). We studied the antioxidant function of HDL and measured serum paraoxonase 1 (PON1) activity, tumor necrosis factor a (TNFa) and intercellular adhesion molecule 1 (ICAM-1) levels in these patients. In a subset of 19 patients, we immunostained gluteal subcutaneous adipose tissue (SAT) for TNFa, macrophages and measured adipocyte size. Results: HDL lipid peroxide (LPO) levels were higher and serum PON1 activity was lower in the high AHI group versus the low AHI group (p<0.05 and p<0.0001, respectively) and in the OSA group versus the “nOSA” group (p¼0.005 and p<0.05 respectively). Serum TNFa and ICAM1 levels and TNFa immunostaining in SAT increased with the severity of OSA. Serum PON1 activity was inversely correlated with AHI (r¼ -0.41, p<0.03) in the OSA group. TNFa expression in SAT directly correlated with AHI (r¼ 0.53, p<0.03) in the subset of 19 patients from whom biopsy was obtained. Conclusion: Increased serum TNFa, ICAM-1 and TNFa expression in SAT provide a mechanistic basis for enhanced inflammation in patients with OSA. Decreased serum PON1 activity, impaired HDL anti-oxidant function and increased adipose tissue inflammation in these patients could be a mechanism for HDL and endothelial dysfunction. EFFECT OF EXTENDED RELEASE NIACIN ON HDL FUNCTIONALITY, APOB LIPOPROTEIN METABOLISM AND MEDIATORS OF VASCULAR INFLAMMATION IN STATIN TREATED PATIENTS Rahul Yadav a, b, Yifen Liu a, See Kwok b, Salam Hama a, Michael France a, b, Ruth Eatough a, Phil Pemberton c, Jonathan Schofield a, b, Paul Durrington a, Handrean Soran a, b a Cardiovascular Research Group, Core Technologies Facility, University of Manchester, UK; b Cardiovascular Trials Unit, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK; c Department of Biochemistry, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK
Abstract Objective: We investigated the influence of extended release niacin/ laropiprant (ERN/LRP) vs. placebo on HDL antioxidant function, cholesterol efflux, apolipoprotein B (apoB) containing lipoproteins metabolism and associated mediators of vascular inflammation in patients who had persistent dyslipidaemia despite receiving high doses of potent statins.
Abstracts / Atherosclerosis 236 (2014) e303ee309
THE IMPACT OF ROUTINE NEXT GENERATION SEQUENCING TESTING FOR FAMILIAL HYPERCHOLESTEROLAEMIA e 5 MONTHS SERVICE EXPERIENCE L. Yarram-Smith a, g, P. Dean a, g, S. O'Shea a, g, G. Dennis a, g, G. Bayly b,g, A. Taylor c, g, A. Day d, g, M. Watson e, g, P. Giles f, g, R. Ayling h, g, K. Haralambos h, g, S. Whatley h, g, I. McDowell h, g, M. Williams a, g a Bristol Genetics Laboratory, Bristol, United Kingdom; b Bristol Royal Infirmary, Bristol, United Kingdom; c Royal United Hospital, Bath, United Kingdom; d Weston General Hospital, Weston-super-Mare, United Kingdom; e Wessex Clinical Genetics Service, Princess Anne Hospital, Southampton, United Kingdom; f Manor Hospital, Moat Road, Walsall, United Kingdom; g Derriford Hospital, Plymouth, United Kingdom; h University Hospital of Wales, Cardiff, United Kingdom
NICE recommends comprehensive genetic testing in all patients clinically diagnosed with FH and genetic cascade testing of at-risk relatives, however, the cost of FH genetic testing still remains a barrier to commissioning. Bristol Genetics Laboratory (BGL) has developed a comprehensive, high throughput diagnostic genetic test for FH using next generation sequencing. The custom-designed targeted capture assay (HaloPlex, Agilent) sequences 4 FH genes; LDLR, PCSK9, APOB and LDLRAP1 and the SLCO1B1 variants (rs2306283 and rs4149056) associated with statininduced myopathy. A control gene is included to aid copy number (deletion/duplication) detection. Data analysis uses an open-source pipeline; alignment (bwa), variant calling (GATK), variant annotation (Geneticist Assistant, SoftGenetics), and copy number analysis (CONTRA/bespoke CNV tool). BGL has provided FH testing since 2008 and our patient cohort now exceeds 900. The NGS service was launched in October 2013, with parallel MLPA testing to further validate copy number detection. To date, 130 patients have been reported with 33 distinct mutations and a 30% (39/130) positive detection rate, the most common mutations being APOB c.10580G>A and LDLR c.313+1G>A. NGS copy number analysis successfully detected 5 LDLR deletions and generated a reportable copy number result in 71% of cases. MLPA will now be used as a reflex test where NGS data is equivocal, generating cost savings. A further 9% (12/130) of patients have variants of unknown significance (VUS) with 11 of these found in APOB. Comprehensive APOB screening was precluded prior to NGS due to the large size of the gene. Recent literature evidence and our service data suggest that there are clinically significant variants outside of the exon 26 hotspot region supporting a comprehensive screening approach. Current cost of NGS diagnostic testing is £250, which may reduce further with increased throughput. We report on our service experience, and future prospects illustrated by interesting case studies. GENETIC VARIANTS OF UNCERTAIN SIGNIFICANCE (VUS) IN FAMILIAL HYPERCHOLESTEROLAEMIA (FH): CAN FAMILY BASED ASSOCIATION STUDIES HELP DETERMINE PATHOGENICITY? K. Haralambos a, *, S.D. Whatley b, R. Edwards c, R. Gingell c, Townsend c, P. Holmans a, A. Clarke a, B.N. Datta b, I.F.W. McDowell b
D.
a Cardiff University, Cardiff, UK; b University Hospital of Wales, Cardiff and Vale Health Board, Cardiff, UK; c All Wales FH Cascade Testing Service, All Wales Medical Genetics Service, Cardiff, UK
* Corresponding author.
genetic association statistical analysis can be used to quantify the likelihood of pathogenicity based on the family relationship, number of subjects, and LDL-C (with adjustment for age and gender), allowing for the genetic relatedness between family members. Data from families who share the same VUS can be combined. Data from 51 family members with 11 different variants has been collected to date, concentrating first on those with more extensive families available for testing. All available members have been tested in three families, with each family having a different VUS in the LDLR gene. Analysis showed the VUS to be significantly associated with LDL-C in two families (c.2087G>A p¼0.007) (c.1073G>A; p¼0.002), but not in the other (c.2098G>A; p¼0.14) indicating that in two families the variant is likely to be pathogenic whereas in the third it is not. This study demonstrates the feasibility and value of a quantitative statistical approach to family studies compared to qualitative segregation studies which do not take into account the concentration of LDL-C. This approach provides useful additional evidence for the genetic diagnostic laboratory which can be shared with other centres using anonymous genetic data bases for FH. The information helps clinicians provide more clarity for their patients and families. THE IMPORTANCE OF CONSIDERING LOW-DENSITY LIPOPROTEIN CHOLESTEROL RESPONSE AS WELL AS CARDIOVASCULAR RISK IN DECIDING WHO CAN BENEFIT FROM STATIN THERAPY. Handrean Soran a, b, Paul Durrington b a
Cardiovascular Trials Unit, Central Manchester University Hospital NHS Foundation Trust, Manchester, UK; b Cardiovascular Research Group, University of Manchester, Manchester, UK Introduction: Statins are in many countries the most frequently prescribed class of medication. In clinical trials statins achieved a mean reduction in low density lipoprotein cholesterol (LDL-C) of 1.07mmol/l and decreased atherosclerotic cardiovascular disease (CVD) incidence by 24% relative to placebo. Guidelines seeking to deploy statin treatment optimally rely heavily on the use of estimates of absolute CVD risk as an arbiter of who should receive statins. Aim: To demonstrate that this is not an effective strategy unless the LDL cholesterol response to statin treatment, which is determined by the choice of statin, its dose and the pre-treatment LDL cholesterol level, is taken into account. Method: The formula for calculating NNT to prevent one CVD event with statin therapy, taking into account the decrease in LDL cholesterol achieved, is derived as follows:Events prevented per 100 people (ε) ¼ Absolute CVD risk* x LDL cholesterol decrease** x 0.22 NNT ¼ 100 ÷ ε NNT ¼ 100 ÷ (absolute CVD risk x LDL cholesterol decrease x 0.22) *% over next 10 years. s**mmol/l. Results: We show that this is easily achieved and can be integrated to cardiovascular risk software. Application of this evidence reveals that many people with high LDL cholesterol levels can benefit more than people currently receiving statin treatment solely on the basis of their absolute CVD risk, whereas others at higher CVD risk, but with lower LDL cholesterol, will derive little benefit. Conclusion: Taking pre-treatment LDL cholesterol, absolute risk and number need to treat in consideration when deciding who should receive statin therapy will lead to a better patient selection. GENDER REASSIGNMENT AND CARDIOVASCULAR RISK Nandini Rao*, Darren Harvey, Anjly Jain, Devaki Nair
Genetic testing of 1191 index patients from lipid clinics in the Wales FH service revealed a pathogenic mutation in 23% and a genetic variant of uncertain significance (VUS) in 8% (102 individuals, 67 variants). A VUS is a DNA sequence variant for which there is insufficient laboratory or clinical evidence to designate the variant as causative or not. Finding a VUS leaves the diagnosis uncertain for patients and cannot be used for family cascade testing. In this study family members are tested for LDL-cholesterol and VUS with the aim of assessing whether the variant tracks with LDL-C. Specialist
Dept of Clinical Biochemistry, Royal Free London NHS Foundation Trust, NW3 2QG, UK
* Corresponding author. Background: Gender reassignment involves psychological, hormonal and surgical interventions to achieve transition to the opposite gender.
Abstracts / Atherosclerosis 236 (2014) e303ee309
Cardiovascular disease (CVD) outcomes in these individuals using sex steroids are sparse and limited. Objective: We describe two patients referred to our Metabolic Lipid clinic for CVD risk assessment and review the literature. Description EW is a 78 y old male-to- female (MF) non-smoker, without family history of premature CVD, on ethinyl oestradiol 50mg patches and warfarin daily. Body mass index (BMI)25.83; waist circumference (WC) 80cm; and BP 146/72mmHg. TC: HDL 6, Lp(a) 0.85g/L, triglycerides 1.2mmol/L and calculated CVD risk is high. IR is a 47 y old, female-to- male (FM) non-smoker with a strong family history of premature CVD, awaiting testosterone therapy. BMI 21.59, WC 78cm and BP 124/78mmHg. TC: HDL 1.94, triglycerides 0.6mmol/L, and calculated CVD risk is low. CIMT e normal. Secondary causes of dyslipidaemia are excluded in both. EW is now on Pravastatin 10mg daily. IR’s CVD risk is being assessed with LpPLA2, Lp (a), and a gene score test to assess gene variants associated with CVD. The family is being tested for LDL mutations related to Familial Hyperlipidemia. Discussion: A European mortality study showed that in MF, ethinyl oestradiol use was linked to a threefold increased risk of death associated with CVD, independent of other risk factors. FM patients did not show this increased risk. A systematic review and meta-analyses on CVD outcomes was inconclusive but suggests that cross hormone therapies increase serum triglycerides in both groups. However, a trivial effect on HDL and systolic BP was noted in FM. Moreover, the relationship between androgens and CVD risk is complicated as endogenous and exogenous testosterone can be metabolised to oestrogens. Also, in European men, Y chromosome can be associated with CVD risk possibly through interactions with immunity and inflammation. THE CLINICAL AND LIFESTYLE DETERMINANTS OF SERUM HDL-C, APOLIPOPROTEIN A-1, PARAOXONASE-1 ACTIVITY AND OXIDISED LDL IN HEALTHY, MEDICATION NAÏVE MIDDLE-AGED ADULTS J.P. Hobkirk a, H. Soran b, d, M.G. Mellis c, P. Pemberton b, d, S. Carroll e a Hull York Medical School, University of Hull, Hull, UK; b Department of Cardiovascular Sciences, University of Manchester, UK; c Carnegie Research Institute, Leeds Metropolitan University, Leeds, UK; d Clinical Biochemistry, Manchester Royal Infirmary, Manchester, UK; e Department of Sport, Health and Exercise Science, University of Hull, Hull, UK
Introduction: HDL cholesterol may underestimate the anti-oxidative potential of HDL. HDL anti-oxidative potential is mediated by PON-1, which metabolises lipid peroxides and impacts on oxidised LDL (ox-LDL) concentrations. We sought to investigate the determinants of HDL-c, apo A-I and PON-1 activity and to ascertain whether HDL-c, apo A-I, PON-1 activity could explain the variance of ox-LDL concentrations in a sub-group of high PON-1 activity (n¼22) >230 or low (n¼22) <63 nmol/min/ml participants. Methods: 221 (72% male) participants were assessed during health assessments at Nuffield Health Medical Centre in Manchester. Participants avoided vigorous physical activity and alcohol 24 hours prior to assessment. Lifestyle factors including smoking status, alcohol intake and physical activity and cardio-respiratory fitness were assesssed. Participants with CVD or T2D were excluded. Fasting blood was taken to measure HDL-c, PON-1 activity, apo AI and ox-LDL and other blood variables. Correlations and regression analysis assessed inter-relationships and determinants of HDL-c, apo A-1, PON-1 activity and ox-LDL. Regression models included age, sex, waist, TG, alcohol, physical activity, fitness, hsCRP and QRISK. Results: The correlation between PON-1 activity and HDL-c (r¼0.12), apo AI (r¼0.11) were non-significant. Waist circumference, TG, alcohol intake, sex and fitness were predictors of HDL-c, accounting for 40.3% of the variance. Waist circumference, TG and alcohol predicted apo A-I concentrations, accounting for 13.1% of the variance. None of the variables measured predicted PON-1 activity. Ox-LDL was not significantly correlated with HDL-c (r¼0-.19) apo A-I (r¼-0.20) or PON-1 activity (r¼0.09) but was to TG (r¼0.69, p<0.001). Furthermore, TG (52%), hs-CRP (7.4%) and age (6.6%) accounted for 66% of the variance in ox-LDL. Discussion: PON-1 activity did not correlate with any clinical or lifestyle variables. Concentrations of ox-LDL were strongly related to TG
e305
concentrations. Lifestyle factors that regulate TG metabolism are an important therapy to decrease highly atherogenic ox-LDL particles. IMPAIRMENT OF HIGH DENSITY LIPOPROTEIN RESISTANCE TO LIPID PEROXIDATION AND ADIPOSE TISSUE INFLAMMATION IN OBESITY COMPLICATED BY OBSTRUCTIVE SLEEP APNEA Rahul Yadav a, b, *, Michael France a, b, Salam Hama a, Yifen Liu a, See Kwok b, Phil Pemberton c, Paul Durrington a, Maria Jeziorska a, Handrean Soran a, b a Cardiovascular Research Group, Core Technologies Facility, University of Manchester, UK; b Cardiovascular Trials Unit, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK; c Department of Biochemistry, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK
* Corresponding author. Abstract Context: Obstructive sleep apnea (OSA) complicates morbid obesity and is associated with increased cardiovascular disease incidence. An increase in circulating markers of chronic inflammation and dysfunctional high density lipoprotein (HDL) occur in severe obesity. Objective: To establish whether the effects of obesity on inflammation and HDL dysfunction are more marked when complicated by OSA. Design and patients: Morbidly obese patients (n¼41) were divided into those whose apnea-hypo-apnea index (AHI) was more or less than the median value and on the presence of OSA (“OSA” and “no OSA (nOSA)” groups). We studied the antioxidant function of HDL and measured serum paraoxonase 1 (PON1) activity, tumor necrosis factor a (TNFa) and intercellular adhesion molecule 1 (ICAM-1) levels in these patients. In a subset of 19 patients, we immunostained gluteal subcutaneous adipose tissue (SAT) for TNFa, macrophages and measured adipocyte size. Results: HDL lipid peroxide (LPO) levels were higher and serum PON1 activity was lower in the high AHI group versus the low AHI group (p<0.05 and p<0.0001, respectively) and in the OSA group versus the “nOSA” group (p¼0.005 and p<0.05 respectively). Serum TNFa and ICAM1 levels and TNFa immunostaining in SAT increased with the severity of OSA. Serum PON1 activity was inversely correlated with AHI (r¼ -0.41, p<0.03) in the OSA group. TNFa expression in SAT directly correlated with AHI (r¼ 0.53, p<0.03) in the subset of 19 patients from whom biopsy was obtained. Conclusion: Increased serum TNFa, ICAM-1 and TNFa expression in SAT provide a mechanistic basis for enhanced inflammation in patients with OSA. Decreased serum PON1 activity, impaired HDL anti-oxidant function and increased adipose tissue inflammation in these patients could be a mechanism for HDL and endothelial dysfunction. EFFECT OF EXTENDED RELEASE NIACIN ON HDL FUNCTIONALITY, APOB LIPOPROTEIN METABOLISM AND MEDIATORS OF VASCULAR INFLAMMATION IN STATIN TREATED PATIENTS Rahul Yadav a, b, Yifen Liu a, See Kwok b, Salam Hama a, Michael France a, b, Ruth Eatough a, Phil Pemberton c, Jonathan Schofield a, b, Paul Durrington a, Handrean Soran a, b a Cardiovascular Research Group, Core Technologies Facility, University of Manchester, UK; b Cardiovascular Trials Unit, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK; c Department of Biochemistry, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK
Abstract Objective: We investigated the influence of extended release niacin/ laropiprant (ERN/LRP) vs. placebo on HDL antioxidant function, cholesterol efflux, apolipoprotein B (apoB) containing lipoproteins metabolism and associated mediators of vascular inflammation in patients who had persistent dyslipidaemia despite receiving high doses of potent statins.