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1. Plasma urate concentration and risk of coronary heart disease: a Mendelian randomisation analysis

Author

White, J, Sofat, R, Hemani, G, Shah, T, Engmann, J, Dale, C, Shah, S, Kruger, FA, Giambartolomei, C, Swerdlow, DI, Palmer, T, McLachlan, S, Langenberg, C, Zabaneh, D, Lovering, R, Cavadino, A, Jefferis, B, Finan, C, Wong, A, Amuzu, A, Ong, K, Gaunt, TR, Warren, H, Davies, TL, Drenos, F, Cooper, J, Ebrahim, S, Lawlor, DA, Talmud, PJ, Humphries, SE, Power, C, Hypponen, E, Richards, M, Hardy, R, Kuh, D, Wareham, N, Ben-Shlomo, Y, Day, IN, Whincup, P, Morris, R, Strachan, MW, Price, J, Kumari, M, Kivimaki, M, Plagnol, V, Whittaker, JC, International Consortium for Blood Pressure (ICBP), Smith, GD, Dudbridge, F, Casas, JP, Holmes, MV, Hingorani, AD, and UCLEB (University College London-London School of Hygiene & Trop

Abstract

BACKGROUND: Increased circulating plasma urate concentration is associated with an increased risk of coronary heart disease, but the extent of any causative effect of urate on risk of coronary heart disease is still unclear. In this study, we aimed to clarify any causal role of urate on coronary heart disease risk using Mendelian randomisation analysis. METHODS: We first did a fixed-effects meta-analysis of the observational association of plasma urate and risk of coronary heart disease. We then used a conventional Mendelian randomisation approach to investigate the causal relevance using a genetic instrument based on 31 urate-associated single nucleotide polymorphisms (SNPs). To account for potential pleiotropic associations of certain SNPs with risk factors other than urate, we additionally did both a multivariable Mendelian randomisation analysis, in which the genetic associations of SNPs with systolic and diastolic blood pressure, HDL cholesterol, and triglycerides were included as covariates, and an Egger Mendelian randomisation (MR-Egger) analysis to estimate a causal effect accounting for unmeasured pleiotropy. FINDINGS: In the meta-analysis of 17 prospective observational studies (166 486 individuals; 9784 coronary heart disease events) a 1 SD higher urate concentration was associated with an odds ratio (OR) for coronary heart disease of 1·07 (95% CI 1·04-1·10). The corresponding OR estimates from the conventional, multivariable adjusted, and Egger Mendelian randomisation analysis (58 studies; 198 598 individuals; 65 877 events) were 1·18 (95% CI 1·08-1·29), 1·10 (1·00-1·22), and 1·05 (0·92-1·20), respectively, per 1 SD increment in plasma urate. INTERPRETATION: Conventional and multivariate Mendelian randomisation analysis implicates a causal role for urate in the development of coronary heart disease, but these estimates might be inflated by hidden pleiotropy. Egger Mendelian randomisation analysis, which accounts for pleiotropy but has less statistical power, suggests there might be no causal effect. These results might help investigators to determine the priority of trials of urate lowering for the prevention of coronary heart disease compared with other potential interventions. FUNDING: UK National Institute for Health Research, British Heart Foundation, and UK Medical Research Council.

Published
2016

2. Association of vitamin D status with arterial blood pressure and hypertension risk: a mendelian randomisation study

Author

Vimaleswaran, KS, Cavadino, A, Berry, DJ, Jorde, R, Dieffenbach, AK, Lu, C, Alves, AC, Heerspink, HJL, Tikkanen, E, Eriksson, J, Wong, A, Mangino, M, Jablonski, KA, Nolte, IM, Houston, DK, Ahluwalia, TS, Van der Most, PJ, Pasko, D, Zgaga, L, Thiering, E, Vitart, V, Fraser, RM, Huffman, JE, De Boer, RA, Schoettker, B, Saum, K-U, McCarthy, MI, Dupuis, J, Herzig, K-H, Sebert, S, Pouta, A, Laitinen, J, Kleber, ME, Navis, G, Lorentzon, M, Jameson, K, Arden, N, Cooper, JA, Acharya, J, Hardy, R, Raitakari, O, Ripatti, S, Billings, LK, Lahti, J, Osmond, C, Penninx, BW, Rejnmark, L, Lohman, KK, Paternoster, L, Stolk, RP, Hernandez, DG, Byberg, L, Hagstrom, E, Melhus, H, Ingelsson, E, Mellstroem, D, Ljunggren, O, Tzoulaki, I, McLachlan, S, Theodoratou, E, Tiesler, CMT, Jula, A, Navarro, P, Wright, AF, Polasek, O, Hayward, C, Wilson, JF, Rudan, I, Salomaa, V, Heinrich, J, Campbell, H, Price, JF, Karlsson, M, Lind, L, Michaesson, K, Bandinelli, S, Frayling, TM, Hartman, CA, Sorensen, TIA, Kritchevsky, SB, Langdahl, BL, Eriksson, JG, Florez, JC, Spector, TD, Lehtimaki, T, Kuh, D, Humphries, SE, Cooper, C, Ohlsson, C, Maerz, W, De Borst, MH, Kumari, M, Kivimaki, M, Wang, TJ, Power, C, Brenner, H, Grimnes, G, Van der Harst, P, Snieder, H, Hingorani, AD, Pilz, S, Whittaker, JC, Jarvelin, M-R, and Hypponen, E

Subjects
Adult, Male, Caroline Hayward, D SUPPLEMENTATION, Oxidoreductases Acting on CH-CH Group Donors, Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium, Polymorphism, Single Nucleotide, DISEASE, Body Mass Index, 1117 Public Health and Health Services, Endocrinology & Metabolism, KIDNEY, GENETIC-VARIANTS, Humans, Genetic Predisposition to Disease, GENOME-WIDE ASSOCIATION, Vitamin D, Cytochrome P450 Family 2, LifeLines Cohort Study investigators, Randomized Controlled Trials as Topic, OUTCOMES, Science & Technology, 1103 Clinical Sciences, Mendelian Randomization Analysis, Middle Aged, Vitamin D Deficiency, Phenotype, 1101 Medical Biochemistry and Metabolomics, Hypertension, Cholestanetriol 26-Monooxygenase, Global Blood Pressure Genetics (Global BPGen) consortium, TRIAL, Female, HEALTH, Life Sciences & Biomedicine, International Consortium for Blood Pressure (ICBP)
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. Funding British Heart Foundation, UK Medical Research Council, and Academy of Finland.

Published
2014

3. Association of vitamin D status with arterial blood pressure and hypertension risk: A mendelian randomisation study

Author

Vimaleswaran, Kerani S., Cavadino, Alana, Berry, Diane J., Jorde, Rolf, Grimnes, Guri, Dieffenbach, Aida Karina, Lu, Chen, Alves, Alexessander Couto, Heerspink, Hiddo J. Lambers, Tikkanen, Emmi, Eriksson, Joel, Wong, Andrew, Mangino, Massimo, Jablonski, Kathleen A., Nolte, Ilja M., Houston, Denise K., Ahluwalia, Tarunveer Singh, van der Most, Peter J., Pasko, Dorota, Zgaga, Lina, Thiering, Elisabeth, Schöttker, B, Saum, KU, Brenner, H, Järvelin, MR, Tzoulaki, I, Snieder, H, Stolk, RP, Hartman, CA, de Boer, RA, van der Harst, P, Navis, G, de Borst, MH, Lorentzon, M, Mellström, D, Ohlsson, C, Hardy, R, Kuh, D, Cooper, JA, Acharya, J, Humphries, SE, Hingorani, AD, Kumari, M, Kivimaki, M, Spector, TD, Kritchevsky, SB, Lohman, KK, Sørensen, TIA, Frayling, TM, Campbell, H, Theodoratou, E, Fraser, RM, Wilson, JF, Rudan, I, Price, JF, McLachlan, S, Vitart, V, Navarro, P, Huffman, JE, Hayward, C, Wright, AF, Tiesler, CMT, Heinrich, J, McCarthy, MI, Ingelsson, E, Arden, N, Cooper, C, Dupuis, J, Herzig, KH, Sebert, S, Pouta, A, Laitinen, J, Kleber, ME, März, W, Jameson, K, Osmond, C, Raitakari, O, Ripatti, S, Lahti, J, Eriksson, JG, Penninx, BW, Billings, LK, Florez, JC, Rejnmark, L, Langdahl, BL, Paternoster, L, Hernandez, DG, Byberg, L, Michaelsson, K, Hagström, E, Melhus, H, Ljunggren, O, Lind, L, Jula, A, Polasek, O, Salomaa, V, Karlsson, M, Bandinelli, S, Lehtimäki, T, Wang, TJ, Pilz, S, and Whittaker, JC

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 aff ect 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 fi nding warrants further investigation in an independent, similarly powered study.

Published
2014

4. Polymorphisms in Natural Killer Cell Receptor Protein 2D (NKG2D) as a Risk Factor for Cholangiocarcinoma.

Author

Wadsworth CA, Dixon PH, Taylor-Robinson S, Kim JU, Zabron AA, Wong JH, Chapman MH, McKay SC, Spalding DR, Wasan HS, Pereira SP, Thomas HC, Whittaker JC, Williamson C, and Khan SA

Abstract

Background and Aims: Understanding of the significant genetic risk factors for Cholangiocarcinoma (CC) remains limited. Polymorphisms in the natural killer cell receptor G2D (NKG2D) gene have been shown to increase risk of CC transformation in patients with Primary Sclerosing Cholangitis (PSC). We present a validation study of NKG2D polymorphisms in CC patients without PSC., Methods: Seven common Single Nucleotide Polymorphisms (SNPs) of the NKG2D gene were genotyped in 164 non-PSC related CC subjects and 257 controls with HaploView. The two SNPs that were positively identified in the previous Scandinavian study, rs11053781 and rs2617167, were included., Results: The seven genotyped SNPs were not associated with risk of CC. Furthermore, haplotype analysis revealed that there was no evidence to suggest that any haplotype differs in frequency between cases and controls ( P  > 0.1)., Conclusion: The common genetic variation in NKG2D does not correlate significantly with sporadic CC risk. This is in contrast to the previous positive findings in the Scandinavian study with PSC-patients. The failure to reproduce the association may reflect an important difference between the pathogenesis of sporadic CC and that of PSC-related CC. Given that genetic susceptibility is likely to be multifaceted and complex, further validation studies that include both sporadic and PSC-related CC are required.

Published
2019
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5. HMG-coenzyme A reductase inhibition, type 2 diabetes, and bodyweight: evidence from genetic analysis and randomised trials.

Author

Swerdlow DI, Preiss D, Kuchenbaecker KB, Holmes MV, Engmann JE, Shah T, Sofat R, Stender S, Johnson PC, Scott RA, Leusink M, Verweij N, Sharp SJ, Guo Y, Giambartolomei C, Chung C, Peasey A, Amuzu A, Li K, Palmen J, Howard P, Cooper JA, Drenos F, Li YR, Lowe G, Gallacher J, Stewart MC, Tzoulaki I, Buxbaum SG, van der A DL, Forouhi NG, Onland-Moret NC, van der Schouw YT, Schnabel RB, Hubacek JA, Kubinova R, Baceviciene M, Tamosiunas A, Pajak A, Topor-Madry R, Stepaniak U, Malyutina S, Baldassarre D, Sennblad B, Tremoli E, de Faire U, Veglia F, Ford I, Jukema JW, Westendorp RG, de Borst GJ, de Jong PA, Algra A, Spiering W, Maitland-van der Zee AH, Klungel OH, de Boer A, Doevendans PA, Eaton CB, Robinson JG, Duggan D, Kjekshus J, Downs JR, Gotto AM, Keech AC, Marchioli R, Tognoni G, Sever PS, Poulter NR, Waters DD, Pedersen TR, Amarenco P, Nakamura H, McMurray JJ, Lewsey JD, Chasman DI, Ridker PM, Maggioni AP, Tavazzi L, Ray KK, Seshasai SR, Manson JE, Price JF, Whincup PH, Morris RW, Lawlor DA, Smith GD, Ben-Shlomo Y, Schreiner PJ, Fornage M, Siscovick DS, Cushman M, Kumari M, Wareham NJ, Verschuren WM, Redline S, Patel SR, Whittaker JC, Hamsten A, Delaney JA, Dale C, Gaunt TR, Wong A, Kuh D, Hardy R, Kathiresan S, Castillo BA, van der Harst P, Brunner EJ, Tybjaerg-Hansen A, Marmot MG, Krauss RM, Tsai M, Coresh J, Hoogeveen RC, Psaty BM, Lange LA, Hakonarson H, Dudbridge F, Humphries SE, Talmud PJ, Kivimäki M, Timpson NJ, Langenberg C, Asselbergs FW, Voevoda M, Bobak M, Pikhart H, Wilson JG, Reiner AP, Keating BJ, Hingorani AD, and Sattar N

Subjects
Aged, Body Mass Index, Cholesterol, HDL metabolism, Cholesterol, LDL metabolism, Female, Genetic Testing, Humans, Male, Middle Aged, Randomized Controlled Trials as Topic, Risk Factors, Body Weight genetics, Diabetes Mellitus, Type 2 genetics, Hydroxymethylglutaryl CoA Reductases genetics, Hydroxymethylglutaryl-CoA Reductase Inhibitors adverse effects, Polymorphism, Single Nucleotide genetics
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., (Copyright © 2015 Swerdlow et al. Open Access article distributed under the terms of CC BY. Published by Elsevier Ltd. All rights reserved.)

Published
2015
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6. The interleukin-6 receptor as a target for prevention of coronary heart disease: a mendelian randomisation analysis.

Author

Swerdlow DI, Holmes MV, Kuchenbaecker KB, Engmann JE, Shah T, Sofat R, Guo Y, Chung C, Peasey A, Pfister R, Mooijaart SP, Ireland HA, Leusink M, Langenberg C, Li KW, Palmen J, Howard P, Cooper JA, Drenos F, Hardy J, Nalls MA, Li YR, Lowe G, Stewart M, Bielinski SJ, Peto J, Timpson NJ, Gallacher J, Dunlop M, Houlston R, Tomlinson I, Tzoulaki I, Luan J, Boer JM, Forouhi NG, Onland-Moret NC, van der Schouw YT, Schnabel RB, Hubacek JA, Kubinova R, Baceviciene M, Tamosiunas A, Pajak A, Topor-Madry R, Malyutina S, Baldassarre D, Sennblad B, Tremoli E, de Faire U, Ferrucci L, Bandenelli S, Tanaka T, Meschia JF, Singleton A, Navis G, Mateo Leach I, Bakker SJ, Gansevoort RT, Ford I, Epstein SE, Burnett MS, Devaney JM, Jukema JW, Westendorp RG, Jan de Borst G, van der Graaf Y, de Jong PA, Mailand-van der Zee AH, Klungel OH, de Boer A, Doevendans PA, Stephens JW, Eaton CB, Robinson JG, Manson JE, Fowkes FG, Frayling TM, Price JF, Whincup PH, Morris RW, Lawlor DA, Smith GD, Ben-Shlomo Y, Redline S, Lange LA, Kumari M, Wareham NJ, Verschuren WM, Benjamin EJ, Whittaker JC, Hamsten A, Dudbridge F, Delaney JA, Wong A, Kuh D, Hardy R, Castillo BA, Connolly JJ, van der Harst P, Brunner EJ, Marmot MG, Wassel CL, Humphries SE, Talmud PJ, Kivimaki M, Asselbergs FW, Voevoda M, Bobak M, Pikhart H, Wilson JG, Hakonarson H, Reiner AP, Keating BJ, Sattar N, Hingorani AD, and Casas JP

Subjects
Antibodies, Monoclonal, Humanized adverse effects, Gene Frequency genetics, Genetic Association Studies, Genetic Variation genetics, Genotype, Humans, Inflammation Mediators blood, Phenotype, Polymorphism, Single Nucleotide genetics, Randomized Controlled Trials as Topic, Signal Transduction drug effects, Signal Transduction genetics, Treatment Outcome, Antibodies, Monoclonal, Humanized therapeutic use, Coronary Disease genetics, Coronary Disease prevention & control, Mendelian Randomization Analysis, Receptors, Interleukin-6 antagonists & inhibitors, Receptors, Interleukin-6 genetics
Abstract

Background: A high circulating concentration of interleukin 6 is associated with increased risk of coronary heart disease. Blockade of the interleukin-6 receptor (IL6R) with a monoclonal antibody (tocilizumab) licensed for treatment of rheumatoid arthritis reduces systemic and articular inflammation. However, whether IL6R blockade also reduces risk of coronary heart disease is unknown., Methods: Applying the mendelian randomisation principle, we used single nucleotide polymorphisms (SNPs) in the gene IL6R to evaluate the likely efficacy and safety of IL6R inhibition for primary prevention of coronary heart disease. We compared genetic findings with the effects of tocilizumab reported in randomised trials in patients with rheumatoid arthritis., Findings: In 40 studies including up to 133,449 individuals, an IL6R SNP (rs7529229) marking a non-synonymous IL6R variant (rs8192284; p.Asp358Ala) was associated with increased circulating log interleukin-6 concentration (increase per allele 9·45%, 95% CI 8·34-10·57) as well as reduced C-reactive protein (decrease per allele 8·35%, 95% CI 7·31-9·38) and fibrinogen concentrations (decrease per allele 0·85%, 95% CI 0·60-1·10). This pattern of effects was consistent with IL6R blockade from infusions of tocilizumab (4-8 mg/kg every 4 weeks) in patients with rheumatoid arthritis studied in randomised trials. In 25,458 coronary heart disease cases and 100,740 controls, the IL6R rs7529229 SNP was associated with a decreased odds of coronary heart disease events (per allele odds ratio 0·95, 95% CI 0·93-0·97, p=1·53×10(-5))., Interpretation: On the basis of genetic evidence in human beings, IL6R signalling seems to have a causal role in development of coronary heart disease. IL6R blockade could provide a novel therapeutic approach to prevention of coronary heart disease that warrants testing in suitably powered randomised trials. Genetic studies in populations could be used more widely to help to validate and prioritise novel drug targets or to repurpose existing agents and targets for new therapeutic uses., Funding: UK Medical Research Council; British Heart Foundation; Rosetrees Trust; US National Heart, Lung, and Blood Institute; Du Pont Pharma; Chest, Heart and Stroke Scotland; Wellcome Trust; Coronary Thrombosis Trust; Northwick Park Institute for Medical Research; UCLH/UCL Comprehensive Medical Research Centre; US National Institute on Aging; Academy of Finland; Netherlands Organisation for Health Research and Development; SANCO; Dutch Ministry of Public Health, Welfare and Sports; World Cancer Research Fund; Agentschap NL; European Commission; Swedish Heart-Lung Foundation; Swedish Research Council; Strategic Cardiovascular Programme of the Karolinska Institutet; Stockholm County Council; US National Institute of Neurological Disorders and Stroke; MedStar Health Research Institute; GlaxoSmithKline; Dutch Kidney Foundation; US National Institutes of Health; Netherlands Interuniversity Cardiology Institute of the Netherlands; Diabetes UK; European Union Seventh Framework Programme; National Institute for Healthy Ageing; Cancer Research UK; MacArthur Foundation., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Published
2012
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7. Effect modification by population dietary folate on the association between MTHFR genotype, homocysteine, and stroke risk: a meta-analysis of genetic studies and randomised trials.

Author

Holmes MV, Newcombe P, Hubacek JA, Sofat R, Ricketts SL, Cooper J, Breteler MM, Bautista LE, Sharma P, Whittaker JC, Smeeth L, Fowkes FG, Algra A, Shmeleva V, Szolnoki Z, Roest M, Linnebank M, Zacho J, Nalls MA, Singleton AB, Ferrucci L, Hardy J, Worrall BB, Rich SS, Matarin M, Norman PE, Flicker L, Almeida OP, van Bockxmeer FM, Shimokata H, Khaw KT, Wareham NJ, Bobak M, Sterne JA, Smith GD, Talmud PJ, van Duijn C, Humphries SE, Price JF, Ebrahim S, Lawlor DA, Hankey GJ, Meschia JF, Sandhu MS, Hingorani AD, and Casas JP

Subjects
Homocysteine genetics, Humans, Randomized Controlled Trials as Topic, Risk Factors, Stroke blood, Stroke genetics, Dietary Supplements, Folic Acid administration & dosage, Homocysteine blood, Methylenetetrahydrofolate Reductase (NADPH2) genetics, Polymorphism, Genetic, Stroke prevention & control, Vitamin B Complex administration & dosage
Abstract

Background: The MTHFR 677C→T polymorphism has been associated with raised homocysteine concentration and increased risk of stroke. A previous overview showed that the effects were greatest in regions with low dietary folate consumption, but differentiation between the effect of folate and small-study bias was difficult. A meta-analysis of randomised trials of homocysteine-lowering interventions showed no reduction in coronary heart disease events or stroke, but the trials were generally set in populations with high folate consumption. We aimed to reduce the effect of small-study bias and investigate whether folate status modifies the association between MTHFR 677C→T and stroke in a genetic analysis and meta-analysis of randomised controlled trials., Methods: We established a collaboration of genetic studies consisting of 237 datasets including 59,995 individuals with data for homocysteine and 20,885 stroke events. We compared the genetic findings with a meta-analysis of 13 randomised trials of homocysteine-lowering treatments and stroke risk (45,549 individuals, 2314 stroke events, 269 transient ischaemic attacks)., Findings: The effect of the MTHFR 677C→T variant on homocysteine concentration was larger in low folate regions (Asia; difference between individuals with TT versus CC genotype, 3·12 μmol/L, 95% CI 2·23 to 4·01) than in areas with folate fortification (America, Australia, and New Zealand, high; 0·13 μmol/L, -0·85 to 1·11). The odds ratio (OR) for stroke was also higher in Asia (1·68, 95% CI 1·44 to 1·97) than in America, Australia, and New Zealand, high (1·03, 0·84 to 1·25). Most randomised trials took place in regions with high or increasing population folate concentrations. The summary relative risk (RR) of stroke in trials of homocysteine-lowering interventions (0·94, 95% CI 0·85 to 1·04) was similar to that predicted for the same extent of homocysteine reduction in large genetic studies in populations with similar folate status (predicted RR 1·00, 95% CI 0·90 to 1·11). Although the predicted effect of homocysteine reduction from large genetic studies in low folate regions (Asia) was larger (RR 0·78, 95% CI 0·68 to 0·90), no trial has evaluated the effect of lowering of homocysteine on stroke risk exclusively in a low folate region., Interpretation: In regions with increasing levels or established policies of population folate supplementation, evidence from genetic studies and randomised trials is concordant in suggesting an absence of benefit from lowering of homocysteine for prevention of stroke. Further large-scale genetic studies of the association between MTHFR 677C→T and stroke in low folate settings are needed to distinguish effect modification by folate from small-study bias. If future randomised trials of homocysteine-lowering interventions for stroke prevention are undertaken, they should take place in regions with low folate consumption., Funding: Full funding sources listed at end of paper (see Acknowledgments)., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Published
2011
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8. High-dose vitamin D supplements are not associated with linear growth in a large Finnish cohort.

Author

Hyppönen E, Fararouei M, Sovio U, Hartikainen AL, Pouta A, Robertson C, Whittaker JC, and Jarvelin MR

Subjects
Adolescent, Adult, Birth Weight, Cohort Studies, Female, Finland, Growth Disorders chemically induced, Growth Disorders prevention & control, Humans, Infant, Infant, Newborn, Male, Nutrition Policy, Prospective Studies, Vitamin D adverse effects, Vitamin D therapeutic use, Vitamin D Deficiency prevention & control, Adolescent Development, Body Height, Child Development, Dietary Supplements adverse effects, Vitamin D administration & dosage
Abstract

High vitamin D intake in childhood has been suggested to have an adverse influence on linear growth. In Finland, in the mid-1960s the official recommendation for infant vitamin D supplementation was 2000 IU/d (50 μg/d). We investigated whether high-dose vitamin D supplementation in infancy was associated with subsequent growth in height. We used data from a prospective population-based birth cohort study including all children due to be born in the 2 northernmost provinces in Finland in 1966 (12,058 live-births, coverage 96%). Information on each participant's height was collected at birth and ages 1, 14, and 31 y, as were possible confounding factors (data for analyses available from 10,060 singletons). Information on the frequency and dose of vitamin D supplementation was collected in 1967 when participants were 1 y of age. A weak association was found between frequency of vitamin D supplementation with greater height at age 1 y (P = 0.005), which was explained by birth characteristics and maternal and social factors (adjusted P = 0.34). Neither frequency nor dose of vitamin D supplementation was associated with height at 14 or 31 y (P > 0.13). To conclude, contrary to proposed evidence suggesting that vitamin D has a negative influence on growth rate at a dosage of ~2000 IU/d, supplementation at this level in the Northern Finland Birth Cohort was not associated with reduced height at any age studied.

Published
2011
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9. Genetic variation in complement factor H and risk of coronary heart disease: eight new studies and a meta-analysis of around 48,000 individuals.

Author

Sofat R, Casas JP, Kumari M, Talmud PJ, Ireland H, Kivimaki M, Marmot M, Hughes AD, Thom S, Ebrahim S, Whittaker JC, Smeeth L, Lawlor DA, Humphries SE, and Hingorani AD

Subjects
Cohort Studies, Female, Genetic Variation, Genotype, Humans, Male, Molecular Epidemiology, Myocardial Infarction genetics, Polymorphism, Single Nucleotide, Risk, Risk Factors, Sequence Analysis, DNA, Triglycerides blood, Complement Factor H genetics, Coronary Disease genetics
Abstract

Objectives: To investigate the association of polymorphisms in complement factor H (CFH) and coronary heart disease (CHD) using meta-analysis., Background: Age-related macular degeneration (AMD) and CHD may share partially overlapping pathogenesis. A non-synonymous SNP (rs1061170/Y402H) in CFH encoding complement factor H (fH) is robustly associated with increased AMD risk but associations with CHD risk have been inconsistent., Methods: We conducted de novo genotyping and genetic association analyses of incident and prevalent CHD in four studies, and in silico analysis of the same association in a further four cohorts. We pooled these data with information from all published studies using random effects meta-analysis, including a total of 48,646 participants of which 9097 were CHD cases. We also evaluated the association of Y402H with known risk factors for CHD by pooling results from new and in silico studies providing relevant data., Results: CFH genotype was not associated with CHD. Compared to the reference TT homozygote group the pooled odds ratio (OR) for individuals homozygous for the C allele was 1.02, 95% CI (0.91, 1.13) and that for heterozygote TC individuals was 1.04 (0.98, 1.10). There was no association of CFH with systolic and diastolic blood pressure, total-, LDL- and HDL-cholesterol, or body mass index. Individuals who were CC compared to TT had higher triglyceride levels: pooled mean difference 0.06 (0.02, 0.10) mmol/L, p=0.005., Conclusions: The AMD-associated CFH genotype is not associated with CHD. With the possible exception of triglycerides, this CFH SNP was not associated with a wide range of other CHD risk factors., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Published
2010
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10. Multiple trial two strategy conflicts.

Author

Whittaker JC and Cannings C

Subjects
Animals, Biological Evolution, Game Theory, Models, Statistical
Abstract

Much work has been done on iterated conflicts where the one-trial conflict is the Prisoner's Dilemma. The present paper is concerned with an iterated contest where the underlying contest has two pure strategies and the underlying payoff matrix is general; this therefore includes the Prisoner's Dilemma as a special case. By limiting the player's memory severely we can almost completely specify the Evolutionary Stable Strategies (ESS) of the two- and infinite-trial conflicts derived from this underlying payoff matrix.

Published
1994
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11. A two-trial two-strategy conflict.

Author

Cannings C and Whittaker JC

Subjects
Animals, Biological Evolution, Game Theory
Abstract

Iterated conflicts allow the possibility of co-operative-like behaviour in games such as the Prisoner's Dilemma. The present paper is an attempt to initiate the study of iterated conflicts when, (a) the number of iterations is fixed and finite and (b) the underlying payoff matrix is general, e.g. a mixed Evolutionary Stable Strategy (ESS) could occur in the non-iterated coflict. These assumptions are in contrast to the Iterated Prisoner's Dilemma. We consider a somewhat special case which none the less produces results of an interesting nature. For those cases where there is no internal ESS in the one trial case the two-trial case is easily resolved. When the former has an internal ESS then the two-trial case yields two ESSs whose supports are a partition of the space of strategies.

Published
1991
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