***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    ***EXAMPLES*** 
    Input: An elevated level of C-reactive protein is a strong predictor of cardiovascular events in elderly persons . Whether C-reactive protein has direct adverse vascular effects or is a marker of aspecific systemic inflammation remains to be determined . The aim of this study was to investigate the relation between C-reactive protein and the occurrence of fatal strokes in elderly persons . In the Leiden 85-Plus Study , a population -based prospect i ve follow-up study , we studied the levels of C-reactive protein in 80 participants who died from stroke within the first 5 years of follow-up . Levels of  C-reactive protein  were determined in serum sample s at baseline . Levels of C-reactive protein  were also determined in 82 control subjects who survived for the first 5 years of follow-up and in 83 participants who died from noncardiovascular causes . Mortality risks were estimated with logistic regression and adjusted for differences in age , sex , smoking , medication , total cholesterol , history of diabetes or hypertension , and previous cardiovascular events . Levels of C-reactive protein at baseline were 2-fold higher in subjects who died from stroke than in control subjects ( median 5.7 versus 2.7 mg/L , P<0.005 ) . The levels of C-reactive protein in subjects who died from stroke or from noncardiovascular causes were similar ( median 5.7 versus 4.9 mg/L , P=0.7 ) . The risk of death from stroke as well as from noncardiovascular causes increased linearly up to 10-fold in subjects with the highest levels of C-reactive protein at baseline ( P<0.001 ) . The levels of C-reactive protein were lower when more time had elapsed between blood sampling and time of death during follow-up ( P=0.01 ) . C-reactive protein is a strong but nonspecific risk factor of fatal stroke in old persons . The data do not support the idea that C-reactive protein has direct vascular effects that underlie fatal cerebrovascular disease Little is known about the prospect i ve associations of fibrinogen , factor VII , or factor VIII with  cardiovascular disease ( CVD ) and mortality in the elderly . At baseline in the Cardiovascular Health Study ( 5888 white and African American men and women ; aged > /=65 years ) , we measured  fibrinogen , factor VIII , and factor VII .  We used sex-stratified stepwise Cox survival analysis to determine relative risks ( RRs ) for CVD events and all-cause mortality ( up to 5 years of follow-up ) , both unadjusted and adjusted for CVD risk factors and sub clinical CVD . After adjustment , comparing the fifth quintile to the first , fibrinogen was significantly associated in men with coronary heart disease events ( RR=2.1 ) and stroke or transient ischemic attack ( RR=1.3 ) , and also with mortality within 2.5 years of follow-up ( RR=5.8 ) and later ( RR=1.7 ) . Factor VIII was significantly associated in men with coronary heart disease events ( RR=1.5 ) and mortality ( RR=1.8 ) , and in women with stroke/transient ischemic attack ( RR=1.4 ) . For both factors , values were higher in those who died , whether causes were CVD-related or non-CVD-related , but highest in CVD death . Factor VII exhibited associations with incident angina ( RR=1.44 ) in men and with death in women ( RR , middle quintile compared with first=0.66 ) . However , in general , factor VII was not consistently associated with CVD events in this population . We conclude that , if confirmed in other studies , the measurement of fibrinogen and /or factor VIII may help identify older individuals at higher risk for CVD events and mortality BACKGROUND Among apparently healthy men , elevated levels of C-reactive protein ( CRP ) , a marker for systemic inflammation , predict risk of myocardial infa rct ion and thromboembolic stroke . Whether increased levels of CRP are also associated with the development of symptomatic peripheral arterial disease ( PAD ) is unknown . METHODS AND RESULTS Using a prospect i ve , nested , case-control design , we measured baseline levels of CRP in 144 apparently healthy men participating in the Physicians ' Health Study who subsequently developed symptomatic PAD ( intermittent claudication or need for revascularization ) and in an equal number of control subjects matched on the basis of age and smoking habit who remained free of vascular disease during a follow-up period of 60 months .  Median CRP levels at baseline were significantly higher among those who subsequently developed PAD ( 1.34 versus 0.99 mg/L ; P=.04 ) . Furthermore , the risks of developing PAD increased significantly with each increasing quartile of baseline CRP concentration such that relative risks of PAD from lowest ( referent ) to highest quartile of CRP were 1.0 , 1.3 , 2.0 , and 2.1 ( Ptrend=.02 ) . Compared with those with no clinical evidence of disease , the subgroup of case patients who required revascularization had the highest baseline CRP levels ( median= 1.75 mg/L ; P= .04 ) ; relative risks from lowest to highest quartile of CRP for this end point were 1.0 , 1.8 , 3.8 , and 4.1 ( Ptrend=.02 ) . Risk estimates were similar after additional control for body mass index , hypercholesterolemia , hypertension , diabetes , and a family history of premature atherosclerosis . CONCLUSIONS These prospect i ve data indicate that among apparently healthy men , baseline levels of CRP predict future risk of developing symptomatic PAD and thus provide further support for the hypothesis that chronic inflammation is important in the pathogenesis of atherothrombosis BACKGROUND AND PURPOSE Several cross-sectional and prospect i ve studies have indicated that high titers of antibodies to Chlamydia pneumoniae and cytomegalovirus ( CMV ) are associated with coronary heart disease . The aim of the present study was to examine whether elevated titers of antibodies to these pathogens are predictive of not only coronary but also cerebrovascular disease . METHODS Serum titers of antibodies to C pneumoniae ( IgM , IgG , IgA , IgG immune complex ) and CMV ( IgG ) were determined at baseline ( n=130 ) and after 3.5 years ( n=111 ) in a total sample of 152 men . All individuals had treated hypertension and at least 1 additional risk factor for cardiovascular disease ( hypercholesterolemia , smoking , or diabetes mellitus ) and constituted 93 % of a r and omly selected subgroup ( n=164 ) of patients participating in a multiple risk factor intervention study . RESULTS Elevations of any or both of the IgA or IgG titers to C pneumoniae at entry or after 3.5 years were found in 84 cases ( 55 % ) . Of those with high titers at entry , 97 % remained high at the 3.5 year reexamination . After 6.5 years of follow-up , high titers to C pneumoniae at entry were associated with an increased risk for future stroke ( relative risk [ RR ] , 8.58 ; P=0.043 ; 95 % CI , 1.07 to 68.82 ) and for any cardiovascular event ( RR , 2.69 ; P=0.042 ; 95 % CI , 1.04 to 6.97 ) . A high serum titer of antibodies to CMV was found in 125 cases ( 85 % ) , and this was not associated with an increased risk of future cardiovascular events . CONCLUSIONS Seropositivity for C pneumoniae , but not for CMV , was associated with an increased risk for future cardiovascular disease and , in particular , stroke OBJECTIVE : To determine whether Helicobacter pylori , a chronic bacterial infection often acquired in childhood , is associated with increased risk of coronary heart disease and stroke later in life . DESIGN : Nested case-control study . SETTING : Prospect i ve study of cardiovascular disease in men aged 40 - 59 years at entry ( 1978 - 1980 ) in 24 British towns . SUBJECTS : 135 cases of myocardial infa rct ion and 137 cases of stroke occurring before December 1991 ; 136 controls were identified , frequency matched to cases by town and age group . METHODS : Serum sample s stored at entry were analysed by an enzyme linked immunosorbent assay for the presence of H pylori specific IgG antibodies . RESULTS : 95 of the myocardial infa rct ion cases ( 70 % ) and 93 ( 68 % ) of the stroke cases were seropositive for H pylori compared with 78 ( 57 % ) of the controls ( odds ratio for myocardial infa rct ion 1.77 , 95 % confidence interval ( CI ) 1.06 to 2.95 , P = 0.03 ; odds ratio for stroke 1.57 , 95 % CI 0.95 to 2.60 , P = 0.07 ) . Helicobacter pylori infection was associated with manual social class , residence in Northern Engl and or Scotl and , cigarette smoking , higher systolic pressure and blood glucose , and a lower height-st and ardised forced expiratory volume in one second . Adjustment for these factors attenuated the relation between H pylori and myocardial infa rct ion ( odds ratio = 1.31 , 95 % CI 0.70 to 2.43 , P = 0.40 ) and effectively abolished the relation with stroke ( odds ratio = 0.96 , 0.46 to 2.02 , P = 0.92 ) . The relation between helicobacter infection and fatal myocardial infa rct ion was slightly stronger ( odds ratio 2.41 , 95 % CI 1.13 to 5.12 ) but was also markedly attenuated after adjustment ( 1.56 , 95 % CI 0.68 to 3.61 ) . CONCLUSION : In this prospect i ve study the association between Helicobacter pylori infection and increased risk of myocardial infa rct ion and stroke was substantially confounded by the relation between this infection , adult social class , and major cardiovascular risk factors BACKGROUND Sinking prebeta lipoprotein is a putative marker for elevated levels of lipoprotein ( a ) . Although prospect i ve data suggest that increased plasma lipoprotein ( a ) is an independent risk factor for coronary heart disease in men , no prospect i ve studies are available in women . METHODS AND RESULTS From 1968 through 1975 , sinking prebeta lipoprotein  was determined by paper electrophoresis in 3103 women Framingham Heart Study participants who were free of prevalent cardiovascular disease . A  sinking prebeta lipoprotein b and was detectable in 434 of the women ( 14 % ) studied . The median follow-up interval was approximately 12 years . Incident cardiovascular disease was associated with b and presence using a proportional hazards model that included age , smoking , body mass index , systolic blood pressure , glucose intolerance , low- and high-density lipoprotein cholesterol , and ECG left ventricular hypertrophy . Multivariable adjusted relative risk estimates ( with 95 % confidence intervals ) for outcomes in the b and present versus absent groups were as follows : myocardial infa rct ion ( 82 events ) , 2.37 ( 1.48 to 3.81 ) ; intermittent claudication ( 62 events ) , 1.94 ( 1.07 to 3.50 ) ; cerebrovascular disease ( 83 events ) , 1.88 ( 1.12 to 3.15 ) ; total coronary heart disease ( 174 events ) , 1.61 ( 1.13 to 2.29 ) ; and total cardiovascular disease ( 305 events ) , 1.44 ( 1.09 to 1.91 ) . A subset analysis indicated that b and presence was 50.9 % sensitive and 95.4 % specific for detecting plasma lipoprotein ( a ) levels of > 30 mg/dL , the threshold value linked to increased cardiovascular disease risk in men . CONCLUSIONS Sinking prebeta lipoprotein was a valid surrogate for elevated lipoprotein ( a ) levels in Framingham Heart Study women . B and presence and , equivalently , elevated plasma lipoprotein ( a ) , was a strong , independent predictor of myocardial infa rct ion , intermittent claudication , and cerebrovascular disease . Confirmation of these findings in other longitudinal studies of women is needed Background : To decide whether a person with certain characteristics should be given any kind of intervention to prevent a cardiovascular event , it would be helpful to classify subjects in low , medium and high risk categories . The study evaluated which well known cerebrovascular and cardiovascular correlates , in particular fibrinogen level and ECG characteristics , are able to predict the occurrence of  stroke in men of the general population using data from three European cohorts participating in EUROSTROKE . Methods : EUROSTROKE is a collaborative project among ongoing European population based cohort studies and design ed as a prospect i ve nested case-control study . For each stroke case two controls were sample d. Strokes were classified according to MONICA criteria or review ed by a panel of four neurologists . Complete data were available of 698 men ( 219 stroke events ) from cohorts in Cardiff ( 84 cases 
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Conclusion : Data on novel risk factors for stroke are lacking compared with the equivalent data for acute coronary events , and there are very few data on specific subtypes of ischaemic stroke