C-reactive protein concentration and risk of coronary heart disease, stroke, and mortality: an individual participant meta-analysis

Emerging Risk Factors Collaboration, Stephen Kaptoge, Emanuele Di Angelantonio, Gordon Lowe, Mark B Pepys, Simon G Thompson, Rory Collins, John Danesh, R W Tipping, C E Ford, S L Pressel, G Walldius, I Jungner, A R Folsom, L Chambless, C M Ballantyne, D Panagiotakos, C Pitsavos, C Chrysohoou, C Stefanadis, M W Knuiman, U Goldbourt, M Benderly, D Tanne, P Whincup, S G Wannamethee, R W Morris, S Kiechl, J Willeit, A Mayr, G Schett, N Wald, S Ebrahim, D Lawlor, J Yarnell, J Gallacher, E Casiglia, V Tikhonoff, P J Nietert, S E Sutherland, D L Bachman, J E Keil, M Cushman, B M Psaty, R Tracy, A Tybjaerg-Hansen, B G Nordestgaard, J Zacho, R Frikke-Schmidt, S Giampaoli, L Palmieri, S Panico, D Vanuzzo, L Pilotto, A Gómez de la Cámara, J A Gómez Gerique, L Simons, J McCallum, Y Friedlander, F G R Fowkes, A Lee, J Taylor, J M Guralnik, C L Phillips, R B Wallace, J M Guralnik, C L Phillips, D G Blazer, J M Guralnik, C L Phillips, C L Phillips, J M Guralnik, K-T Khaw, H Brenner, E Raum, H Müller, D Rothenbacher, J-H Jansson, P Wennberg, A Nissinen, C Donfrancesco, S Giampaoli, V Salomaa, K Harald, P Jousilahti, E Vartiainen, M Woodward, R B D'Agostino, P A Wolf, R S Vasan, E J Benjamin, E-M Bladbjerg, T Jørgensen, L Møller, J Jespersen, R Dankner, A Chetrit, F Lubin, A Rosengren, L Wilhelmsen, G Lappas, H Eriksson, C Björkelund, L Lissner, C Bengtsson, P Cremer, D Nagel, R S Tilvis, T E Strandberg, Y Kiyohara, H Arima, Y Doi, T Ninomiya, B Rodriguez, J Dekker, G Nijpels, C D A Stehouwer, E Rimm, J K Pai, S Sato, H Iso, A Kitamura, H Noda, U Goldbourt, J T Salonen, K Nyyssönen, T-P Tuomainen, J A Laukkanen, D J H Deeg, M A Bremmer, T W Meade, J A Cooper, B Hedblad, G Berglund, G Engström, W M M Verschuren, A Blokstra, M Cushman, A R Folsom, B M Psaty, S Shea, A Döring, W Koenig, C Meisinger, W M M Verschuren, A Blokstra, H B Bueno-de-Mesquita, L Wilhelmsen, A Rosengren, G Lappas, L H Kuller, G Grandits, R Selmer, A Tverdal, W Nystad, R F Gillum, M Mussolino, E Rimm, S Hankinson, J E Manson, J K Pai, V Salomaa, K Harald, P Jousilahti, E Vartiainen, T W Meade, J A Cooper, C Knottenbelt, J A Cooper, K A Bauer, K Davidson, S Kirkland, J Shaffer, M R Korin, S Sato, A Kitamura, Y Naito, H Iso, I Holme, R Selmer, A Tverdal, W Nystad, H Nakagawa, K Miura, P Ducimetiere, X Jouven, G Luc, C J Crespo, M R Garcia-Palmieri, P Amouyel, D Arveiler, A Evans, J Ferrieres, H Schulte, G Assmann, C J Packard, N Sattar, R G Westendorp, B M Buckley, B Cantin, B Lamarche, J-P Després, G R Dagenais, E Barrett-Connor, D L Wingard, R R Bettencourt, V Gudnason, T Aspelund, G Sigurdsson, B Thorsson, M Trevisan, J Witteman, I Kardys, M M B Breteler, A Hofman, H Tunstall-Pedoe, R Tavendale, G Lowe, M Woodward, B V Howard, Y Zhang, L Best, J Umans, Y Ben-Shlomo, G Davey-Smith, A Onat, T W Meade, I Njølstad, E B Mathiesen, M-L Løchen, T Wilsgaard, E Ingelsson, S Basu, T Cederholm, L Byberg, J M Gaziano, M Stampfer, P M Ridker, J M Gaziano, P M Ridker, H Ulmer, G Diem, H Concin, A Tosetto, F Rodeghiero, S Wassertheil-Smoller, J E Manson, I M Marmot, R Clarke, R Collins, A Fletcher, E Brunner, M Shipley, P M Ridker, J Buring, J Shepherd, S Cobbe, I Ford, M Robertson, Y He, A Marin Ibañez, E J M Feskens, M Walker, S Watson, R Collins, E Di Angelantonio, S Erqou, S Kaptoge, S Lewington, L Pennells, P L Perry, K K Ray, N Sarwar, M Alexander, A Thompson, S G Thompson, M Walker, S Watson, I R White, A M Wood, J Danesh, Emerging Risk Factors Collaboration, Stephen Kaptoge, Emanuele Di Angelantonio, Gordon Lowe, Mark B Pepys, Simon G Thompson, Rory Collins, John Danesh, R W Tipping, C E Ford, S L Pressel, G Walldius, I Jungner, A R Folsom, L Chambless, C M Ballantyne, D Panagiotakos, C Pitsavos, C Chrysohoou, C Stefanadis, M W Knuiman, U Goldbourt, M Benderly, D Tanne, P Whincup, S G Wannamethee, R W Morris, S Kiechl, J Willeit, A Mayr, G Schett, N Wald, S Ebrahim, D Lawlor, J Yarnell, J Gallacher, E Casiglia, V Tikhonoff, P J Nietert, S E Sutherland, D L Bachman, J E Keil, M Cushman, B M Psaty, R Tracy, A Tybjaerg-Hansen, B G Nordestgaard, J Zacho, R Frikke-Schmidt, S Giampaoli, L Palmieri, S Panico, D Vanuzzo, L Pilotto, A Gómez de la Cámara, J A Gómez Gerique, L Simons, J McCallum, Y Friedlander, F G R Fowkes, A Lee, J Taylor, J M Guralnik, C L Phillips, R B Wallace, J M Guralnik, C L Phillips, D G Blazer, J M Guralnik, C L Phillips, C L Phillips, J M Guralnik, K-T Khaw, H Brenner, E Raum, H Müller, D Rothenbacher, J-H Jansson, P Wennberg, A Nissinen, C Donfrancesco, S Giampaoli, V Salomaa, K Harald, P Jousilahti, E Vartiainen, M Woodward, R B D'Agostino, P A Wolf, R S Vasan, E J Benjamin, E-M Bladbjerg, T Jørgensen, L Møller, J Jespersen, R Dankner, A Chetrit, F Lubin, A Rosengren, L Wilhelmsen, G Lappas, H Eriksson, C Björkelund, L Lissner, C Bengtsson, P Cremer, D Nagel, R S Tilvis, T E Strandberg, Y Kiyohara, H Arima, Y Doi, T Ninomiya, B Rodriguez, J Dekker, G Nijpels, C D A Stehouwer, E Rimm, J K Pai, S Sato, H Iso, A Kitamura, H Noda, U Goldbourt, J T Salonen, K Nyyssönen, T-P Tuomainen, J A Laukkanen, D J H Deeg, M A Bremmer, T W Meade, J A Cooper, B Hedblad, G Berglund, G Engström, W M M Verschuren, A Blokstra, M Cushman, A R Folsom, B M Psaty, S Shea, A Döring, W Koenig, C Meisinger, W M M Verschuren, A Blokstra, H B Bueno-de-Mesquita, L Wilhelmsen, A Rosengren, G Lappas, L H Kuller, G Grandits, R Selmer, A Tverdal, W Nystad, R F Gillum, M Mussolino, E Rimm, S Hankinson, J E Manson, J K Pai, V Salomaa, K Harald, P Jousilahti, E Vartiainen, T W Meade, J A Cooper, C Knottenbelt, J A Cooper, K A Bauer, K Davidson, S Kirkland, J Shaffer, M R Korin, S Sato, A Kitamura, Y Naito, H Iso, I Holme, R Selmer, A Tverdal, W Nystad, H Nakagawa, K Miura, P Ducimetiere, X Jouven, G Luc, C J Crespo, M R Garcia-Palmieri, P Amouyel, D Arveiler, A Evans, J Ferrieres, H Schulte, G Assmann, C J Packard, N Sattar, R G Westendorp, B M Buckley, B Cantin, B Lamarche, J-P Després, G R Dagenais, E Barrett-Connor, D L Wingard, R R Bettencourt, V Gudnason, T Aspelund, G Sigurdsson, B Thorsson, M Trevisan, J Witteman, I Kardys, M M B Breteler, A Hofman, H Tunstall-Pedoe, R Tavendale, G Lowe, M Woodward, B V Howard, Y Zhang, L Best, J Umans, Y Ben-Shlomo, G Davey-Smith, A Onat, T W Meade, I Njølstad, E B Mathiesen, M-L Løchen, T Wilsgaard, E Ingelsson, S Basu, T Cederholm, L Byberg, J M Gaziano, M Stampfer, P M Ridker, J M Gaziano, P M Ridker, H Ulmer, G Diem, H Concin, A Tosetto, F Rodeghiero, S Wassertheil-Smoller, J E Manson, I M Marmot, R Clarke, R Collins, A Fletcher, E Brunner, M Shipley, P M Ridker, J Buring, J Shepherd, S Cobbe, I Ford, M Robertson, Y He, A Marin Ibañez, E J M Feskens, M Walker, S Watson, R Collins, E Di Angelantonio, S Erqou, S Kaptoge, S Lewington, L Pennells, P L Perry, K K Ray, N Sarwar, M Alexander, A Thompson, S G Thompson, M Walker, S Watson, I R White, A M Wood, J Danesh

Abstract

Background: Associations of C-reactive protein (CRP) concentration with risk of major diseases can best be assessed by long-term prospective follow-up of large numbers of people. We assessed the associations of CRP concentration with risk of vascular and non-vascular outcomes under different circumstances.

Methods: We meta-analysed individual records of 160 309 people without a history of vascular disease (ie, 1.31 million person-years at risk, 27 769 fatal or non-fatal disease outcomes) from 54 long-term prospective studies. Within-study regression analyses were adjusted for within-person variation in risk factor levels.

Results: Log(e) CRP concentration was linearly associated with several conventional risk factors and inflammatory markers, and nearly log-linearly with the risk of ischaemic vascular disease and non-vascular mortality. Risk ratios (RRs) for coronary heart disease per 1-SD higher log(e) CRP concentration (three-fold higher) were 1.63 (95% CI 1.51-1.76) when initially adjusted for age and sex only, and 1.37 (1.27-1.48) when adjusted further for conventional risk factors; 1.44 (1.32-1.57) and 1.27 (1.15-1.40) for ischaemic stroke; 1.71 (1.53-1.91) and 1.55 (1.37-1.76) for vascular mortality; and 1.55 (1.41-1.69) and 1.54 (1.40-1.68) for non-vascular mortality. RRs were largely unchanged after exclusion of smokers or initial follow-up. After further adjustment for fibrinogen, the corresponding RRs were 1.23 (1.07-1.42) for coronary heart disease; 1.32 (1.18-1.49) for ischaemic stroke; 1.34 (1.18-1.52) for vascular mortality; and 1.34 (1.20-1.50) for non-vascular mortality.

Interpretation: CRP concentration has continuous associations with the risk of coronary heart disease, ischaemic stroke, vascular mortality, and death from several cancers and lung disease that are each of broadly similar size. The relevance of CRP to such a range of disorders is unclear. Associations with ischaemic vascular disease depend considerably on conventional risk factors and other markers of inflammation.

Funding: British Heart Foundation, UK Medical Research Council, BUPA Foundation, and GlaxoSmithKline.

Copyright 2010 Elsevier Ltd. All rights reserved.

Figures

Figure 1
Figure 1
Geometric mean C-reactive protein (CRP) concentration in men and women according to cohort and assay source (A) and within 5-year bands adjusted for cohort (B) Data from the third National Health and Nutrition Examination Survey (NHANESIII) and Population Study of Women in Göteborg (GOTOW) are not represented in the graph because they did not use high sensitivity CRP assays. NS=not stated. Error bars represent the 95% CIs.
Figure 2
Figure 2
Cross-sectional associations between geometric mean C-reactive protein (CRP) concentration and some conventional risk factors and other characteristics Mean CRP concentration was adjusted to age 50 years. Error bars represent the 95% CIs. BP=blood pressure. r=Pearson's correlation coefficient (95% CI) for association between the risk marker and loge CRP concentration in men and women combined.
Figure 3
Figure 3
Risk ratios for major vascular and non-vascular outcomes by quantiles of C-reactive protein (CRP) concentration, with different degree of adjustment for potential confounders Adjusted study-specific loge risk ratios were combined by use of multivariate random-effects meta-analysis. The adjustments were age, sex, and study only (A); age, sex, study, systolic blood pressure, smoking, history of diabetes, body-mass index, concentrations of loge triglycerides, non-HDL cholesterol, and HDL cholesterol, and alcohol consumption (B); and (A) plus (B) plus fibrinogen (C). Studies with fewer than ten cases of any outcome were excluded from the analysis of that outcome. Error bars represent the 95% CIs, calculated using floating absolute risk technique. The sizes of the boxes are proportional to the inverse of the variance of the risk ratios.
Figure 4
Figure 4
Age-adjusted and sex-adjusted risk ratios for mortality from vascular and non-vascular diseases per three-fold higher usual C-reactive protein (CRP) concentration Data are numbers, unless otherwise indicated. Risk ratios (boxes) were adjusted only for age, and stratified (when appropriate), by sex and trial group. Studies with fewer than ten cases of any outcome were excluded from the analysis of that outcome. The risk ratios are presented per 1·11 higher loge CRP (ie, 1-SD), corresponding to a three-fold higher CRP concentration. Horizontal lines represent the 95% CIs. The sizes of the boxes are proportional to the inverse of the variance of the risk ratios.

References

    1. Pepys MB, Hirschfield GM. C-reactive protein: a critical update. J Clin Invest. 2003;111:1805–1812.
    1. Gabay C, Kushner I. Acute-phase proteins and other systemic responses to inflammation. N Engl J Med. 1999;340:448–454.
    1. Emberson JR, Whincup PH, Morris RW, Walker M, Lowe GD, Rumley A. Extent of regression dilution for established and novel coronary risk factors: results from the British Regional Heart Study. Eur J Cardiovasc Prev Rehabil. 2004;11:125–134.
    1. Pearson TA, Mensah GA, Alexander RW. Markers of inflammation and cardiovascular disease: application to clinical and public health practice: a statement for healthcare professionals from the Centers for Disease Control and Prevention and the American Heart Association. Circulation. 2003;107:499–511.
    1. Kuller LH, Tracy RP, Shaten J, Meilahn EN. Relation of C-reactive protein and coronary heart disease in the MRFIT nested case-control study. Multiple Risk Factor Intervention Trial. Am J Epidemiol. 1996;144:537–547.
    1. Ridker PM, Cushman M, Stampfer MJ, Tracy RP, Hennekens CH. Inflammation, aspirin, and the risk of cardiovascular disease in apparently healthy men. N Engl J Med. 1997;336:973–979.
    1. Danesh J, Wheeler JG, Hirschfield GM. C-reactive protein and other circulating markers of inflammation in the prediction of coronary heart disease. N Engl J Med. 2004;350:1387–1397.
    1. Ridker PM, Hennekens CH, Buring JE, Rifai N. C-reactive protein and other markers of inflammation in the prediction of cardiovascular disease in women. N Engl J Med. 2000;342:836–843.
    1. Ridker PM, Buring JE, Rifai N, Cook NR. Development and validation of improved algorithms for the assessment of global cardiovascular risk in women: the Reynolds risk score. JAMA. 2007;297:611–619.
    1. Scirica BM, Morrow DA. Is C-reactive protein an innocent bystander or proatherogenic culprit? The verdict is still out. Circulation. 2006;113:2128–2134.
    1. Verma S, Devaraj S, Jialal I. Is C-reactive protein an innocent bystander or proatherogenic culprit? C-reactive protein promotes atherothrombosis. Circulation. 2006;113:2135–2150.
    1. de Beer FC, Soutar AK, Baltz ML, Trayner IM, Feinstein A, Pepys MB. Low density lipoprotein and very low density lipoprotein are selectively bound by aggregated C-reactive protein. J Exp Med. 1982;156:230–242.
    1. Pepys MB, Rowe IF, Baltz ML. C-reactive protein: binding to lipids and lipoproteins. Int Rev Exp Pathol. 1985;27:83–111.
    1. Zhang YX, Cliff WJ, Schoefl GI, Higgins G. Coronary C-reactive protein distribution: its relation to development of atherosclerosis. Atherosclerosis. 1999;145:375–379.
    1. Bos MJ, Schipper CM, Koudstaal PJ, Witteman JC, Hofman A, Breteler MM. High serum C-reactive protein level is not an independent predictor for stroke: the Rotterdam Study. Circulation. 2006;114:1591–1598.
    1. Kaplan RC, McGinn AP, Baird AE. Inflammation and hemostasis biomarkers for predicting stroke in postmenopausal women: the Women's Health Initiative Observational Study. J Stroke Cerebrovasc Dis. 2008;17:344–355.
    1. Andersson J, Johansson L, Ladenvall P. C-reactive protein is a determinant of first-ever stroke: prospective nested case-referent study. Cerebrovasc Dis. 2009;27:544–551.
    1. Casas JP, Shah T, Hingorani AD, Danesh J, Pepys MB. C-reactive protein and coronary heart disease: a critical review. J Intern Med. 2008;264:295–314.
    1. Emerging Risk Factors Collaboration. Danesh J, Erqou S, Walker M. The Emerging Risk Factors Collaboration: analysis of individual data on lipid, inflammatory and other markers in over 1·1 million participants in 104 prospective studies of cardiovascular diseases. Eur J Epidemiol. 2007;22:839–869.
    1. Tunstall-Pedoe H, Kuulasmaa K, Amouyel P. Myocardial infarction and coronary deaths in the World Health Organization MONICA Project. Registration procedures, event rates, and case-fatality rates in 38 populations from 21 countries in four continents. Circulation. 1994;90:583–612.
    1. Emerging Risk Factors Collaboration. Erqou S, Kaptoge S, Perry PL. Lipoprotein(a) concentration and the risk of coronary heart disease, stroke, and nonvascular mortality. JAMA. 2009;302:412–423.
    1. Fibrinogen Studies Collaboration. Kaptoge S, White IR, Thompson SG. Associations of plasma fibrinogen levels with established cardiovascular disease risk factors, inflammatory markers, and other characteristics: individual participant meta-analysis of 154 211 adults in 31 prospective studies: the fibrinogen studies collaboration. Am J Epidemiol. 2007;166:867–879.
    1. Fibrinogen Studies Collaboration. Danesh J, Lewington S, Thompson SG. Plasma fibrinogen level and the risk of major cardiovascular diseases and nonvascular mortality: an individual participant meta-analysis. JAMA. 2005;294:1799–1809.
    1. Friedewald WT, Levy RI, Fredrickson DS. Estimation of the concentration of low-density lipoprotein cholesterol in plasma, without use of the preparative ultracentrifuge. Clin Chem. 1972;18:499–502.
    1. Emerging Risk Factors Collaboration. Di Angelantonio E, Sarwar N, Kaptoge S. Major lipids, apolipoproteins, and risk of vascular disease. JAMA. 2009;302:1993–2000.
    1. Fibrinogen Studies Collaboration. Wood AM, White I, Thompson SG, Lewington S, Danesh J. Regression dilution methods for meta-analysis: assessing long-term variability in plasma fibrinogen among 27 247 adults in 15 prospective studies. Int J Epidemiol. 2006;35:1570–1578.
    1. Fibrinogen Studies Collaboration. Wood AM, White I, Thompson SG. Correcting for multivariate measurement error by regression calibration in meta-analyses of epidemiological studies. Stat Med. 2009;28:1067–1092.
    1. Danesh J, Collins R, Appleby P, Peto R. Association of fibrinogen, C-reactive protein, albumin, or leukocyte count with coronary heart disease: meta-analyses of prospective studies. JAMA. 1998;279:1477–1482.
    1. Andresdottir MB, Sigfusson N, Sigvaldason H, Gudnason V. Erythrocyte sedimentation rate, an independent predictor of coronary heart disease in men and women: the Reykjavik Study. Am J Epidemiol. 2003;158:844–851.
    1. Kundu JK, Surh YJ. Inflammation: gearing the journey to cancer. Mutat Res. 2008;659:15–30.
    1. Danesh J, Kaptoge S, Mann AG. Long-term interleukin-6 levels and subsequent risk of coronary heart disease: two new prospective studies and a systematic review. PLoS Med. 2008;5:e78.
    1. Hansson GK. Inflammation, atherosclerosis, and coronary artery disease. N Engl J Med. 2005;352:1685–1695.
    1. Clarke R, Emberson JR, Breeze E. Biomarkers of inflammation predict both vascular and non-vascular mortality in older men. Eur Heart J. 2008;29:800–809.
    1. Heikkila K, Harris R, Lowe G. Associations of circulating C-reactive protein and interleukin-6 with cancer risk: findings from two prospective cohorts and a meta-analysis. Cancer Causes Control. 2009;20:15–26.
    1. Elliott P, Chambers JC, Zhang W. Genetic loci associated with C-reactive protein levels and risk of coronary heart disease. JAMA. 2009;302:37–48.
    1. Casas JP, Shah T, Cooper J. Insight into the nature of the CRP-coronary event association using Mendelian randomization. Int J Epidemiol. 2006;35:922–931.
    1. Timpson NJ, Lawlor DA, Harbord RM. C-reactive protein and its role in metabolic syndrome: mendelian randomisation study. Lancet. 2005;366:1954–2009.
    1. Zacho J, Tybjaerg-Hansen A, Jensen JS, Grande P, Sillesen H, Nordestgaard BG. Genetically elevated C-reactive protein and ischemic vascular disease. N Engl J Med. 2008;359:1897–1908.
    1. Lange LA, Carlson CS, Hindorff LA. Association of polymorphisms in the CRP gene with circulating C-reactive protein levels and cardiovascular events. JAMA. 2006;296:2703–2711.
    1. Kinlay S. Low-density lipoprotein-dependent and -independent effects of cholesterol-lowering therapies on C-reactive protein: a meta-analysis. J Am Coll Cardiol. 2007;49:2003–2009.
    1. Ridker PM, Danielson E, Fonseca FA. Rosuvastatin to prevent vascular events in men and women with elevated C-reactive protein. N Engl J Med. 2008;359:2195–2207.
    1. Clarke R, Shipley M, Lewington S. Underestimation of risk associations due to regression dilution in long-term follow-up of prospective studies. Am J Epidemiol. 1999;150:341–353.
    1. Kelley-Hedgepeth A, Lloyd-Jones DM, Colvin A. Ethnic differences in C-reactive protein concentrations. Clin Chem. 2008;54:1027–1037.
    1. Packard CJ. Lipoprotein-associated phospholipase A2 as a biomarker of coronary heart disease and a therapeutic target. Curr Opin Cardiol. 2009;24:358–363.
    1. Yudkin JS, Stehouwer CD, Emeis JJ, Coppack SW. C-reactive protein in healthy subjects: associations with obesity, insulin resistance, and endothelial dysfunction: a potential role for cytokines originating from adipose tissue? Arterioscler Thromb Vasc Biol. 1999;19:972–978.
    1. Lawlor DA, Smith GD, Rumley A, Lowe GD, Ebrahim S. Associations of fibrinogen and C-reactive protein with prevalent and incident coronary heart disease are attenuated by adjustment for confounding factors. British Women's Heart and Health Study. Thromb Haemost. 2005;93:955–963.
    1. Danesh J, Saracci R, Berglund G. EPIC-Heart: the cardiovascular component of a prospective study of nutritional, lifestyle and biological factors in 520 000 middle-aged participants from 10 European countries. Eur J Epidemiol. 2007;22:129–141.
    1. Fibrinogen Studies Collaboration. Pennells L, White IR, Wood AM, Kaptoge S, Sarwar N. Measures to assess the prognostic ability of the stratified Cox proportional hazards model. Stat Med. 2009;28:389–411.
    1. Pencina MJ, D'Agostino RB, Sr, D'Agostino RB, Jr, Vasan RS. Evaluating the added predictive ability of a new marker: from area under the ROC curve to reclassification and beyond. Stat Med. 2008;27:157–172.
    1. Shah T, Casas JP, Cooper JA. Critical appraisal of CRP measurement for the prediction of coronary heart disease events: new data and systematic review of 31 prospective cohorts. Int J Epidemiol. 2009;38:217–231.

Source: PubMed

3
Prenumerera