Jackie A Cooper

University College London, Londinium, England, United Kingdom

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Publications (77)706.66 Total impact

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    ABSTRACT: Background Numerous risk prediction algorithms based on conventional risk factors for Coronary Heart Disease (CHD) are available but provide only modest discrimination. The inclusion of genetic information may improve clinical utility. Methods We tested the use of two gene scores (GS) in the prospective second Northwick Park Heart Study (NPHSII) of 2775 healthy UK men (284 cases), and Pakistani case-control studies from Islamabad/Rawalpindi (321 cases/228 controls) and Lahore (414 cases/219 controls). The 19-SNP GS included SNPs in loci identified by GWAS and candidate gene studies, while the 13-SNP GS only included SNPs in loci identified by the CARDIoGRAMplusC4D consortium. Results In NPHSII, the mean of both gene scores was higher in those who went on to develop CHD over 13.5 years of follow-up (19-SNP p=0.01, 13-SNP p=7x10<sup>-3</sup>). In combination with the Framingha
    PLoS ONE 07/2015; 10(7-7):e0130754. DOI:10.1371/journal.pone.0130754 · 3.23 Impact Factor
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    ABSTRACT: Peroxisome proliferator-activated receptor gamma (PPARγ) is an important regulator of metabolic health and a common polymorphism in the PPAR-γ2 gene (PPARG2) may modify associations between lifestyle behaviour and health. To investigate whether the PPARG2 Pro12Ala genotype modifies the associations of sedentary behaviour and moderate-to-vigorous intensity physical activity (MVPA) with common measures of insulin sensitivity. Participants with a high risk of impaired glucose regulation were recruited, United Kingdom, 2010-2011. Sedentary and MVPA time were objectively measured using accelerometers. Fasting and 2-hour post-challenge insulin and glucose were assessed; insulin sensitivity was calculated using Matsuda-ISI and HOMA-IS. DNA was extracted from whole blood. Linear regression examined associations of sedentary time and MVPA with insulin sensitivity and examined interactions by PPARG2 Pro12Ala genotype. 541 subjects were included (average age = 65 years, female = 33%); 18% carried the Ala12 allele. Both sedentary time and MVPA were strongly associated with HOMA-IS and Matsuda-ISI after adjustment for age, sex, ethnicity, medication, smoking status and accelerometer wear time. After further adjustment for each other and BMI, only associations with Matsuda-ISI were maintained. Every 30 minute difference in sedentary time was inversely associated with a 4% (0, 8%; p = 0.043) difference in Matsuda-ISI, whereas every 30 minutes in MVPA was positively associated with a 13% (0, 26%; p = 0.048) difference. The association of MVPA with Matsuda-ISI was modified by genotype (p = 0.005) and only maintained in Ala12 allele carriers. Conversely, sedentary time was not modified by genotype and remained inversely associated with insulin sensitivity in Pro12 allele homozygotes. The association of MVPA with Matsuda-ISI was modified by PPARG2 Pro12Ala genotype with significant associations only observed in the 18% of the population who carried the Ala12 allele, whereas associations with sedentary time were unaffected.
    PLoS ONE 05/2015; 10(5):e0124062. DOI:10.1371/journal.pone.0124062 · 3.23 Impact Factor
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    ABSTRACT: -Observational studies report that secretory phospholipase A2 (sPLA2) activity is a marker for CHD risk, and activity measures are thought to represent the composite activity of sPLA2-IIA, -V and -X. The aim of this study was to use genetic variants of PLA2G10, encoding sPLA2-X, to investigate the contribution of sPLA2-X to the measure of sPLA2 activity, and coronary heart disease (CHD) risk traits and outcome. -Three PLA2G10 tagging SNPs (rs72546339, rs72546340, rs4003232) and a previously studied PLA2G10 cSNP rs4003228, R38C, were genotyped in a nested case: control cohort drawn from the prospective EPIC-Norfolk Study (2175 cases and 2175 controls). Meta-analysis of rs4003228 (R38C) and CHD was carried out using data from the Northwick Park Heart Study II and two published cohorts AtheroGene and SIPLAC, providing in total an additional 1884 cases and 3119 controls. EPIC-Norfolk subjects in the highest tertile of sPLA2 activity were older and had higher inflammatory markers compared to those in the lowest tertile for sPLA2 activity. None of the PLA2G10 tSNPs nor R38C, a functional variant, were significantly associated with sPLA2 activity, intermediate CHD risk traits or CHD risk. In meta-analysis the summary OR for R38C was OR=0.97 (95%CI 0.77-1.22). -PLA2G10 variants are not significantly associated with plasma sPLA2 activity or with CHD risk.
    Circulation Cardiovascular Genetics 01/2015; 8(2). DOI:10.1161/CIRCGENETICS.114.000633 · 5.34 Impact Factor
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    ABSTRACT: We developed a 65-T2D variant weighted gene score to examine the impact on T2D risk assessment in a UK-based consortium of prospective studies, initially free from type 2 diabetes (T2D) (N=13,294; 37.3% women; mean age 58.5 (38-99) years). We compared the performance of the gene score with the phenotypically-derived Framingham Offspring Study T2D risk model, and then the two in combination. Over the median 10 years follow-up, 804 participants developed T2D. The odds ratio for T2D (top vs. bottom quintiles of gene score) was 2.70 (95%CI 2.12-3.43). With a 10% false positive rate, the genetic score alone detected 19.9% incident cases, the Framingham risk model 30.7%, and together, 37.3%. The respective area under the receiver operator characteristic curves were 0.60 (95% CI: 0.58-0.62), 0.75 (95% CI: 0.73 to 0.77) and 0.76 (95% CI: 0.75 to 0.78). The combined risk scores Net Reclassification Improvement (NRI) was 8.1% (5.0 to 11.2) p=3.31x10(-7). While BMI stratification into tertiles influenced the NRI (95% CI) (BMI<24.5kg/m(2) (27.6% (17.7 to 37.5) p=4.82x10(-8)); 24.5-27.5kg/m(2) (11.6% (5.8 to 17.4) p=9.88x10(-5)); >27.5kg/m(2) (2.6% (-1.4 to 6.6) p=0.20), age categories did not. The addition of the gene score to a phenotypic risk model leads to a potentially clinically important improvement in discrimination of incident T2D. © 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.
    Diabetes 12/2014; 64(5). DOI:10.2337/db14-1504 · 8.47 Impact Factor
  • Atherosclerosis 12/2014; 237(2):e12-e13. DOI:10.1016/j.atherosclerosis.2014.10.071 · 3.97 Impact Factor
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    ABSTRACT: Familial hypercholesterolemia (FH) is an autosomal-dominant disorder caused by mutations in 1 of 3 genes. In the 60% of patients who are mutation negative, we have recently shown that the clinical phenotype can be associated with an accumulation of common small-effect LDL cholesterol (LDL-C)-raising alleles by use of a 12-single nucleotide polymorphism (12-SNP) score. The aims of the study were to improve the selection of SNPs and replicate the results in additional samples. We used ROC curves to determine the optimum number of LDL-C SNPs. For replication analysis, we genotyped patients with a clinical diagnosis of FH from 6 countries for 6 LDL-C-associated alleles. We compared the weighted SNP score among patients with no confirmed mutation (FH/M-), those with a mutation (FH/M+), and controls from a UK population sample (WHII). Increasing the number of SNPs to 33 did not improve the ability of the score to discriminate between FH/M- and controls, whereas sequential removal of SNPs with smaller effects/lower frequency showed that a weighted score of 6 SNPs performed as well as the 12-SNP score. Metaanalysis of the weighted 6-SNP score, on the basis of polymorphisms in CELSR2 (cadherin, EGF LAG 7-pass G-type receptor 2), APOB (apolipoprotein B), ABCG5/8 [ATP-binding cassette, sub-family G (WHITE), member 5/8], LDLR (low density lipoprotein receptor), and APOE (apolipoprotein E) loci, in the independent FH/M- cohorts showed a consistently higher score in comparison to the WHII population (P < 2.2 × 10(-16)). Modeling in individuals with a 6-SNP score in the top three-fourths of the score distribution indicated a >95% likelihood of a polygenic explanation of their increased LDL-C. A 6-SNP LDL-C score consistently distinguishes FH/M- patients from healthy subjects. The hypercholesterolemia in 88% of mutation-negative patients is likely to have a polygenic basis. © 2014 The American Association for Clinical Chemistry.
    Clinical Chemistry 11/2014; 61(1). DOI:10.1373/clinchem.2014.231365 · 7.77 Impact Factor
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    ABSTRACT: Background Statins increase the risk of new-onset type 2 diabetes mellitus. We aimed to assess whether this increase in risk is a consequence of inhibition of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), the intended drug target. Methods We used single nucleotide polymorphisms in the HMGCR gene, rs17238484 (for the main analysis) and rs12916 (for a subsidiary analysis) as proxies for HMGCR inhibition by statins. We examined associations of these variants with plasma lipid, glucose, and insulin concentrations; bodyweight; waist circumference; and prevalent and incident type 2 diabetes. Study-specific effect estimates per copy of each LDL-lowering allele were pooled by meta-analysis. These findings were compared with a meta-analysis of new-onset type 2 diabetes and bodyweight change data from randomised trials of statin drugs. The effects of statins in each randomised trial were assessed using meta-analysis. Findings Data were available for up to 223 463 individuals from 43 genetic studies. Each additional rs17238484-G allele was associated with a mean 0·06 mmol/L (95% CI 0·05–0·07) lower LDL cholesterol and higher body weight (0·30 kg, 0·18–0·43), waist circumference (0·32 cm, 0·16–0·47), plasma insulin concentration (1·62%, 0·53–2·72), and plasma glucose concentration (0·23%, 0·02–0·44). The rs12916 SNP had similar effects on LDL cholesterol, bodyweight, and waist circumference. The rs17238484-G allele seemed to be associated with higher risk of type 2 diabetes (odds ratio [OR] per allele 1·02, 95% CI 1·00–1·05); the rs12916-T allele association was consistent (1·06, 1·03–1·09). In 129 170 individuals in randomised trials, statins lowered LDL cholesterol by 0·92 mmol/L (95% CI 0·18–1·67) at 1-year of follow-up, increased bodyweight by 0·24 kg (95% CI 0·10–0·38 in all trials; 0·33 kg, 95% CI 0·24–0·42 in placebo or standard care controlled trials and −0·15 kg, 95% CI −0·39 to 0·08 in intensive-dose vs moderate-dose trials) at a mean of 4·2 years (range 1·9–6·7) of follow-up, and increased the odds of new-onset type 2 diabetes (OR 1·12, 95% CI 1·06–1·18 in all trials; 1·11, 95% CI 1·03–1·20 in placebo or standard care controlled trials and 1·12, 95% CI 1·04–1·22 in intensive-dose vs moderate dose trials). Interpretation The increased risk of type 2 diabetes noted with statins is at least partially explained by HMGCR inhibition. Funding The funding sources are cited at the end of the paper.
    09/2014; DOI:10.1016/S0140-6736(14)61183-1
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    ABSTRACT: ABSTRACT Objective: To determine the sequence variant of TLL1 gene (rs1503298, T > C) in three British cohorts (PREDICT, UDACS and ED) of patients with type-2 Diabetes mellitus (T2DM) in order to assess its association with coronary heart disease (CHD).
    Journal of the College of Physicians and Surgeons--Pakistan: JCPSP 09/2014; 24(9):615-9. · 0.32 Impact Factor
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    ABSTRACT: Background Low plasma 25-hydroxyvitamin D (25[OH]D) concentration is associated with high arterial blood pressure and hypertension risk, but whether this association is causal is unknown. We used a mendelian randomisation approach to test whether 25(OH)D concentration is causally associated with blood pressure and hypertension risk. Methods In this mendelian randomisation study, we generated an allele score (25[OH]D synthesis score) based on variants of genes that affect 25(OH)D synthesis or substrate availability (CYP2R1 and DHCR7), which we used as a proxy for 25(OH)D concentration. We meta-analysed data for up to 108 173 individuals from 35 studies in the D-CarDia collaboration to investigate associations between the allele score and blood pressure measurements. We complemented these analyses with previously published summary statistics from the International Consortium on Blood Pressure (ICBP), the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium, and the Global Blood Pressure Genetics (Global BPGen) consortium. Findings In phenotypic analyses (up to n=49 363), increased 25(OH)D concentration was associated with decreased systolic blood pressure (β per 10% increase, −0·12 mm Hg, 95% CI −0·20 to −0·04; p=0·003) and reduced odds of hypertension (odds ratio [OR] 0·98, 95% CI 0·97—0·99; p=0·0003), but not with decreased diastolic blood pressure (β per 10% increase, −0·02 mm Hg, −0·08 to 0·03; p=0·37). In meta-analyses in which we combined data from D-CarDia and the ICBP (n=146 581, after exclusion of overlapping studies), each 25(OH)D-increasing allele of the synthesis score was associated with a change of −0·10 mm Hg in systolic blood pressure (−0·21 to −0·0001; p=0·0498) and a change of −0·08 mm Hg in diastolic blood pressure (−0·15 to −0·02; p=0·01). When D-CarDia and consortia data for hypertension were meta-analysed together (n=142 255), the synthesis score was associated with a reduced odds of hypertension (OR per allele, 0·98, 0·96—0·99; p=0·001). In instrumental variable analysis, each 10% increase in genetically instrumented 25(OH)D concentration was associated with a change of −0·29 mm Hg in diastolic blood pressure (−0·52 to −0·07; p=0·01), a change of −0·37 mm Hg in systolic blood pressure (−0·73 to 0·003; p=0·052), and an 8·1% decreased odds of hypertension (OR 0·92, 0·87—0·97; p=0·002). Interpretation Increased plasma concentrations of 25(OH)D might reduce the risk of hypertension. This finding warrants further investigation in an independent, similarly powered study.
    The Lancet Diabetes & Endocrinology 06/2014; DOI:10.1016/S2213-8587(14)70113-5 · 9.19 Impact Factor
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    ABSTRACT: -Telomere length is a heritable trait and short telomere length has been associated with multiple chronic diseases. We investigated the relationship of relative leukocyte telomere length (RTL) with cardiometabolic risk and performed the first GWAS and meta-analysis to identify variants influencing RTL in a population of Sikhs from South Asia. -Our results revealed a significant independent association of shorter RTL with type 2 diabetes (T2D) and heart disease. Our discovery GWAS (n=1,616) was followed by Stage 1 replication of 25 top signals (P<10(-6)) in an additional Sikhs (n=2,397). On combined discovery and Stage 1 meta-analysis (n= 4013), we identified a novel RTL locus at chromosome 16q21 represented by an intronic variant (rs74019828) in the CSNK2A2 gene (β -0.38, P=4.5x10(-8)). We further tested 3 top variants by genotyping in UKCVD (Caucasians n=2,952) for Stage 2. Next we performed in silico replication of 139 top signals (p<10(-5)) in UKTWIN, NHS, PLCO and MDACC (n=10,033) and joint meta-analysis (n=16,998). The observed signal in CSNK2A2 was confined to South Asians and could not be replicated in Caucasians due to significant difference in allele frequencies (P<0.001). CSNK2A2 phosphorylates TRF1 and plays an important role for regulation of telomere length homoeostasis. -By identification of a novel signal in telomere pathway genes, our study provides new molecular insight into the underlying mechanism that may regulate telomere length and its association with human aging and cardiometabolic pathophysiology.
    Circulation Cardiovascular Genetics 05/2014; 7(3). DOI:10.1161/CIRCGENETICS.113.000412 · 5.34 Impact Factor
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    ABSTRACT: We sought association of genetic variants in the renin-angiotensin system (RAS) and vitamin D system with acute pancreatitis (AP) development and severity. The endocrine RAS is involved in circulatory homeostasis through the pressor action of angiotensin II at its AT1 receptor. However, local RAS regulate growth and inflammation in diverse cells and tissues, and their activity may be suppressed by vitamin D. Intrapancreatic angiotensin II generation has been implicated in the development of AP. Five hundred forty-four white patients with AP from 3 countries (United Kingdom, 22; Germany, 136; and The Netherlands 386) and 8487 control subjects (United Kingdom 7833, The Netherlands 717) were genotyped for 8 polymorphisms of the RAS/vitamin D systems, chosen on the basis of likely functionality. The angiotensin-converting enzyme I (rather than D) allele was significantly associated with alcohol-related AP when all cohorts were combined (P = 0.03). The renin rs5707 G (rather than A) allele was associated with AP (P = 0.002), infected necrosis (P = 0.025) and mortality (P = 0.046). The association of 2 RAS polymorphisms with AP suggests the need for further detailed analysis of the role of RAS/vitamin D in the genesis or severity of AP, particularly given the ready potential for pharmacological manipulation of this system using existing marketed agents. However, further replication studies will be required before any such association is considered robust, particularly given the significant heterogeneity of AP causation and clinical course.
    Annals of surgery 04/2014; 261(1). DOI:10.1097/SLA.0000000000000655 · 7.19 Impact Factor
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    ABSTRACT: -Secretory phospholipase A2 (sPLA2) enzymes are considered to play a role in atherosclerosis. sPLA2 activity encompasses several sPLA2 isoenzymes, including sPLA2-V. While observational studies show strong association between elevated sPLA2 activity and CHD, no assay to measure sPLA2-V levels exists and the only evidence linking the sPLA2-V isoform to atherosclerosis progression comes from animal studies. In the absence of an assay that directly quantifies sPLA2-V levels, we used PLA2G5 mRNA levels in a novel, modified Mendelian randomization approach to investigate the hypothesized causal role of sPLA2-V in coronary heart disease (CHD) pathogenesis. -Using data from the Advanced Study of Aortic Pathology, we identified the single nucleotide polymorphism (SNP) in PLA2G5 showing strongest association with PLA2G5 mRNA expression levels, as a proxy for sPLA2-V levels. We tested the association of this SNP with sPLA2 activity and CHD events in four prospective and 14 case-control studies with 27,230 events and 70,500 controls. rs525380C>A showed the strongest association with PLA2G5 mRNA expression (P=5.1x10(-6)). There was no association of rs525380C>A with plasma sPLA2 activity (difference in geometric mean of sPLA2 activity per rs525380 A-allele 0.4% (95%CI: -0.9%, 1.6%), P=0.56). In meta-analyses, the odds ratio for CHD per A allele was 1.02 (95% CI: 0.99, 1.04; P=0.20). -This novel approach for SNP selection for this modified Mendelian randomization analysis showed no association between rs525380 (the lead SNP for PLA2G5 expression, a surrogate for sPLA2-V levels) and CHD events. The evidence does not support a causal role for sPLA2-V in CHD.
    Circulation Cardiovascular Genetics 02/2014; 7(2). DOI:10.1161/CIRCGENETICS.113.000271 · 5.34 Impact Factor
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    ABSTRACT: To replicate the associations of leukocyte telomere length (LTL) with variants at four loci and to investigate their associations with coronary heart disease (CHD) and type II diabetes (T2D), in order to examine possible causal effects of telomere maintenance machinery on disease aetiology. Four SNPs at three loci BICD1 (rs2630578 GγC), 18q12.2 (rs2162440 GγT), and OBFC1 (rs10786775 CγG, rs11591710 AγC) were genotyped in four studies comprised of 2353 subjects out of which 1148 had CHD and 566 T2D. Three SNPs (rs12696304 CγG, rs10936601G>T and rs16847897 GγC) at the TERC locus were genotyped in these four studies, in addition to an offspring study of 765 healthy students. For all samples, LTL had been measured using a real-time PCR-based method. Only one SNP was associated with a significant effect on LTL, with the minor allele G of OBFC1 rs10786775 SNP being associated with longer LTL (β=0.029, P=0.04). No SNPs were significantly associated with CHD or T2D. For OBFC1 the haplotype carrying both rare alleles (rs10786775G and rs11591710C, haplotype frequency 0.089) was associated with lower CHD prevalence (OR: 0.77; 95% CI: 0.61-0.97; P= 0.03). The TERC haplotype GTC (rs12696304G, rs10936601T and rs16847897C, haplotype frequency 0.210) was associated with lower risk for both CHD (OR: 0.86; 95% CI: 0.75-0.99; P=0.04) and T2D (OR: 0.74; 95% CI: 0.61-0.91; P= 0.004), with no effect on LTL. Only the last association remained after adjusting for multiple testing. Of reported associations, only that between the OBFC1 rs10786775 SNP and LTL was confirmed, although our study has a limited power to detect modest effects. A 2-SNP OBFC1 haplotype was associated with higher risk of CHD, and a 3-SNP TERC haplotype was associated with both higher risk of CHD and T2D. Further work is required to confirm these results and explore the mechanisms of these effects.
    PLoS ONE 12/2013; 8(12):e83122. DOI:10.1371/journal.pone.0083122 · 3.23 Impact Factor
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    ABSTRACT: Preoperative anaemia and low exertional oxygen uptake are both associated with greater postoperative morbidity and mortality. This study reports the association among haemoglobin concentration ([Hb]), peak oxygen uptake (V˙O2 peak) and anaerobic threshold (AT) in elective surgical patients. Between 1999 and 2011, preoperative [Hb] and cardiopulmonary exercise tests were recorded in 1,777 preoperative patients in four hospitals. The associations between [Hb], V˙O2 peak and AT were analysed by linear regression and covariance. In 436 (24.5%) patients, [Hb] was <12 g dl-1 and, in 83 of these, <10 g dl-1. Both AT and V˙O2 peak rose modestly with increasing [Hb] (r2 = 0.24, P <0.0001 and r2 = 0.30, P <0.0001, respectively). After covariate adjustment, an increase in [Hb] of one standard deviation was associated with a 6.7 to 9.7% increase in V˙O2 peak, and a rise of 4.4 to 6.0% in AT. Haemoglobin concentration accounted for 9% and 6% of the variation in V˙O2 peak and AT respectively. To a modest extent, lower haemoglobin concentrations are independently associated with lower oxygen uptake during preoperative cardiopulmonary exercise testing. It is unknown whether this association is causative.
    09/2013; 2(1):18. DOI:10.1186/2047-0525-2-18
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    ABSTRACT: To investigate the role of secretory phospholipase A2-(sPLA2)-IIA in cardiovascular disease. Higher circulating levels of sPLA2-IIA mass or sPLA2 enzyme activity have been associated with increased risk of cardiovascular events. However, it is not clear if this association is causal. A recent phase-III clinical trial of an sPLA2 inhibitor (varespladib) was stopped prematurely for lack of efficacy. We conducted a Mendelian randomization meta-analysis of 19 general population studies (8021 incident, 7513 prevalent major vascular events (MVE) in 74,683 individuals) and ten acute coronary syndrome (ACS) cohorts (2520 recurrent MVE in 18,355 individuals) using rs11573156, a variant in PLA2G2A encoding the sPLA2-IIA isoenzyme, as an instrumental variable. PLA2G2A rs11573156 C-allele associated with lower circulating sPLA2-IIA mass (38-44%) and sPLA2 enzyme activity (3-23%) per C allele. The odds ratio (OR) for MVE per rs11573156 C-allele was 1.02(95%CI:0.98,1.06) in general populations and 0.96(95%CI:0.90,1.03) in ACS cohorts. In the general population studies, the OR derived from the genetic instrumental variable analysis for MVE for a 1 log unit lower sPLA2-IIA mass was 1.04(95%CI:0.96,1.13), and differed from the non-genetic observational estimate (OR0.69;95%CI:0.61,0.79). In the ACS cohorts, both the genetic instrumental variable and observational ORs showed a null association with MVE. Instrumental variable analysis failed to show associations between sPLA2 enzyme activity and MVE. Reducing sPLA2-IIA mass is unlikely to be a useful therapeutic goal for preventing cardiovascular events.
    Journal of the American College of Cardiology 07/2013; 62(21). DOI:10.1016/j.jacc.2013.06.044 · 15.34 Impact Factor
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    ABSTRACT: Aim To determine the frequency and spectrum of mutations causing Familial Hypercholesterolaemia (FH) in patients attending a single UK specialist hospital lipid clinic in Oxford and to identify characteristics contributing to a high mutation detection rate. Methods 289 patients (272 probands) were screened sequentially over a 2-year period for mutations in LDLR, APOB and PCSK9 using standard molecular genetic techniques. The Simon Broome (SB) clinical diagnostic criteria were used to classify patients and a separate cohort of 409 FH patients was used for replication. Results An FH-causing mutation was found in 101 unrelated patients (LDLR = 54 different mutations, APOB p.(Arg3527Gln) = 10, PCSK9 p.(Asp374Tyr) = 0). In the 60 SB Definite FH patients the mutation detection rate was 73% while in the 142 with Possible FH the rate was significantly lower (27%, p < 0.0001), but similar (14%, p = 0.06) to the 70 in whom there was insufficient data to make a clinical diagnosis. The mutation detection rate varied significantly (p = 9.83 × 10−5) by untreated total cholesterol (TC) levels (25% in those <8.1 mmol/l and 74% in those >10.0 mmol/l), and by triglyceride levels (20% in those >2.16 mmol/l and 60% in those <1.0 mmol/l (p = 0.0005)), with both effects confirmed in the replication sample (p for trend = 0.0001 and p = 1.8 × 10−6 respectively). There was no difference in the specificity or sensitivity of the SB criteria versus the Dutch Lipid Clinic Network score in identifying mutation carriers (AROC respectively 0.73 and 0.72, p = 0.68). Conclusions In this genetically heterogeneous cohort of FH patients the mutation detection rate was significantly dependent on pre-treatment TC and triglyceride levels.
    Atherosclerosis 04/2013; 229(1). DOI:10.1016/j.atherosclerosis.2013.04.011 · 3.97 Impact Factor
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    ABSTRACT: BACKGROUND: Familial hypercholesterolaemia is a common autosomal-dominant disorder caused by mutations in three known genes. DNA-based cascade testing is recommended by UK guidelines to identify affected relatives; however, about 60% of patients are mutation-negative. We assessed the hypothesis that familial hypercholesterolaemia can also be caused by an accumulation of common small-effect LDL-C-raising alleles. METHODS: In November, 2011, we assembled a sample of patients with familial hypercholesterolaemia from three UK-based sources and compared them with a healthy control sample from the UK Whitehall II (WHII) study. We also studied patients from a Belgian lipid clinic (Hôpital de Jolimont, Haine St-Paul, Belgium) for validation analyses. We genotyped participants for 12 common LDL-C-raising alleles identified by the Global Lipid Genetics Consortium and constructed a weighted LDL-C-raising gene score. We compared the gene score distribution among patients with familial hypercholesterolaemia with no confirmed mutation, those with an identified mutation, and controls from WHII. FINDINGS: We recruited 321 mutation-negative UK patients (451 Belgian), 319 mutation-positive UK patients (273 Belgian), and 3020 controls from WHII. The mean weighted LDL-C gene score of the WHII participants (0·90 [SD 0·23]) was strongly associated with LDL-C concentration (p=1·4 × 10(-77); R(2)=0·11). Mutation-negative UK patients had a significantly higher mean weighted LDL-C score (1·0 [SD 0·21]) than did WHII controls (p=4·5 × 10(-16)), as did the mutation-negative Belgian patients (0·99 [0·19]; p=5·2 × 10(-20)). The score was also higher in UK (0·95 [0·20]; p=1·6 × 10(-5)) and Belgian (0·92 [0·20]; p=0·04) mutation-positive patients than in WHII controls. 167 (52%) of 321 mutation-negative UK patients had a score within the top three deciles of the WHII weighted LDL-C gene score distribution, and only 35 (11%) fell within the lowest three deciles. INTERPRETATION: In a substantial proportion of patients with familial hypercholesterolaemia without a known mutation, their raised LDL-C concentrations might have a polygenic cause, which could compromise the efficiency of cascade testing. In patients with a detected mutation, a substantial polygenic contribution might add to the variable penetrance of the disease. FUNDING: British Heart Foundation, Pfizer, AstraZeneca, Schering-Plough, National Institute for Health Research, Medical Research Council, Health and Safety Executive, Department of Health, National Heart Lung and Blood Institute, National Institute on Aging, Agency for Health Care Policy Research, John D and Catherine T MacArthur Foundation Research Networks on Successful Midlife Development and Socio-economic Status and Health, Unilever, and Departments of Health and Trade and Industry.
    The Lancet 02/2013; 381(9874). DOI:10.1016/S0140-6736(12)62127-8 · 45.22 Impact Factor
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    ABSTRACT: OBJECTIVE: Increased cardiovascular risk has been associated with high levels of serum antibodies to citrullinated proteins (ACPA) in patients with rheumatoid arthritis (RA). Citrullination is part of many chronic inflammatory processes and we therefore investigated whether ACPA might be associated with coronary artery disease, in the absence of RA. METHODS: To maximize the potential predictive value of this retrospective study we included sera from a cohort of 3052 healthy male individuals, subsequently followed for the development of coronary artery disease, and documented for other disease risk factors. With each case event (myocardial infarction; n = 144), 2 matched controls were assigned. RESULTS: We found 10.4% of cases were ACPA positive compared to 3.8% of controls (odds ratio (95% CI) = 3.26 (1.36-7.80), p = 0.008), remaining significant after adjustment for classical risk factors including smoking and CRP (4.23 (1.22-14.61) p = 0.02). CONCLUSION: The genesis and fine specificity of ACPA in patients with atherosclerosis, in the absence of Rheumatoid arthritis, may prove worthy of further investigation.
    Atherosclerosis 02/2013; 228(1). DOI:10.1016/j.atherosclerosis.2013.02.009 · 3.97 Impact Factor
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    ABSTRACT: The primary role of apolipoprotein E (apoE) is to mediate the cellular uptake of lipoproteins. However, a new role for apoE as a regulator of bone metabolism in mice has recently been established. In contrast to mice, the human APOE gene is characterized by three common isoforms APOE ε2, ε3 and ε4 that result in different metabolic properties of the apoE isoforms, but it remains controversial whether the APOE polymorphism influences bone traits in humans. To clarify this, we investigated bone phenotypes of apoE knock-in mice, which express one human isoform each (apoE2 k.i., apoE3 k.i., apoE4 k.i.) in place of the mouse apoE. Analysis of 12 week-old female knock-in mice revealed increased levels of biochemical bone formation and resorption markers in apoE2 k.i. animals as compared to apoE3 k.i. and apoE4 k.i., with a reduced OPG/RANKL ratio in apoE2 k.i., indicating increased turnover with prevailing resorption in apoE2 k.i.. Accordingly, histomorphometric and µCT analyses demonstrated significantly lower trabecular bone mass in apoE2 than in apoE3 and apoE4 k.i. animals, which was reflected by a significant reduction of lumbar vertebrae maximum force resistance. Unlike trabecular bone, femoral cortical thickness, and stability was not differentially affected by the apoE isoforms. To extend these observations to the human situation, plasma from middle-aged healthy men homozygous for ε2/ε2, ε3/ε3, and ε4/ε4 (n = 21, n = 80, n = 55 respectively) was analyzed with regard to bone turnover markers. In analogy to apoE2 k.i. mice, a lower OPG/RANKL ratio was observed in the serum of ε2/ε2 carriers as compared to ε3/ε3 and ε4/ε4 individuals (p = 0.02 for ε2/ε2 vs ε4/ε4). In conclusion, the current data strongly underline the general importance of apoE as a regulator of bone metabolism and identifies the APOE ε2 allele as a potential genetic risk factor for low trabecular bone mass and vertebral fractures in humans. © 2012 American Society for Bone and Mineral Research.
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 02/2013; 28(2). DOI:10.1002/jbmr.1757 · 6.59 Impact Factor
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    ABSTRACT: There is debate about the value of assessing levels of C-reactive protein (CRP) and other biomarkers of inflammation for the prediction of first cardiovascular events. We analyzed data from 52 prospective studies that included 246,669 participants without a history of cardiovascular disease to investigate the value of adding CRP or fibrinogen levels to conventional risk factors for the prediction of cardiovascular risk. We calculated measures of discrimination and reclassification during follow-up and modeled the clinical implications of initiation of statin therapy after the assessment of CRP or fibrinogen. The addition of information on high-density lipoprotein cholesterol to a prognostic model for cardiovascular disease that included age, sex, smoking status, blood pressure, history of diabetes, and total cholesterol level increased the C-index, a measure of risk discrimination, by 0.0050. The further addition to this model of information on CRP or fibrinogen increased the C-index by 0.0039 and 0.0027, respectively (P<0.001), and yielded a net reclassification improvement of 1.52% and 0.83%, respectively, for the predicted 10-year risk categories of "low" (<10%), "intermediate" (10% to <20%), and "high" (≥20%) (P<0.02 for both comparisons). We estimated that among 100,000 adults 40 years of age or older, 15,025 persons would initially be classified as being at intermediate risk for a cardiovascular event if conventional risk factors alone were used to calculate risk. Assuming that statin therapy would be initiated in accordance with Adult Treatment Panel III guidelines (i.e., for persons with a predicted risk of ≥20% and for those with certain other risk factors, such as diabetes, irrespective of their 10-year predicted risk), additional targeted assessment of CRP or fibrinogen levels in the 13,199 remaining participants at intermediate risk could help prevent approximately 30 additional cardiovascular events over the course of 10 years. In a study of people without known cardiovascular disease, we estimated that under current treatment guidelines, assessment of the CRP or fibrinogen level in people at intermediate risk for a cardiovascular event could help prevent one additional event over a period of 10 years for every 400 to 500 people screened. (Funded by the British Heart Foundation and others.).
    New England Journal of Medicine 10/2012; 367(14):1310-20. DOI:10.1056/NEJMoa1107477 · 54.42 Impact Factor

Publication Stats

3k Citations
706.66 Total Impact Points

Institutions

  • 2008–2015
    • University College London
      • • Institute of Cardiovascular Science
      • • Faculty of Population Health Sciences
      • • Centre for Cardiovascular Biology and Medicine
      • • Division of Medicine
      Londinium, England, United Kingdom
  • 2014
    • University of Oxford
      Oxford, England, United Kingdom