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there is a relative paucity of data on clinical outcomes of elderly patients undergoing contemporary percutaneous coronary interventions ( pcis ) with drug eluting stents ( dess ) .
elderly patients have been frequently excluded from randomized clinical trials because of multiple comorbidities making available data on des difficult to generalize to older patients .
several reports indicated that older age ( > 65 years old and particularly > 75 years old ) is an independent predictor of adverse events after percutaneous coronary interventions ( pcis ) with higher inhospital vascular complications and cardiac death [ 2 , 3 ] and higher long term cardiac mortality .
other reports suggested that older age , after adjusting for various clinical and procedural variables , does not appear to independently predict adverse early or late outcomes after pci [ 5 , 6 ] .
the paclitaxel - eluting stent ( pes ) taxus liberte ( boston scientific , natick , ma , usa ) and the everolimus - eluting stent ( ees ) xience ( or promus ) ( abbott laboratories , abbott park , il , usa ) are drug eluting stents ( dess ) that showed lower tvr than bare metal stents ( bmss ) irrespective of age , although higher mortality and myocardial infarction seem to increase with higher age groups .   in this report , we examine our own data for differences between younger ( < 65 years ) and older ( 65 years ) patients in target lesion failure ( tlf ) in an unselected consecutive series of patients treated with the ees and pes stents and followed for at least 2 years at our medical center .
unselected consecutive patients treated with the pes and ees stents were retrospectively recruited from a single center .
patients who received mixed stents during the index procedure or bypass graft treatment were excluded .
demographics , clinical , procedural , and angiographic variables are shown in tables 1 and 2 . angiographic variables ( including ejection fraction from left ventriculography )
were obtained by an independent blinded review of the angiograms to patients ' clinical variables and outcomes .  
followup was completed at 2 years from the index procedure using medical records , phone calls , or both .
patients were mailed a brief letter describing the protocol , followed by a phone call to obtain verbal consent to be part of the study .
patients who died during the follow - up period had their death certificates retrieved to verify the cause of death .   
the primary outcome of the study was differences in target lesion failure ( tlf ) defined as cardiac death , nonfatal myocardial infarction related to target vessel and target lesion revascularization ( tlr ) between younger ( < 65 years ) and older patients ( 65 years ) patients .
differences in secondary outcomes ( target vessel revascularization ( tvr ) , target vessel failure ( tvf ) , acute stent thrombosis ( st ) as defined by the academic research consortium ( arc ) , nonfatal mi , and cardiac death ) were prespecified as secondary endpoints .   
t - testing was used for continuous variables and chi - square testing for dichotomous variables .
univariate analysis compared the demographic , clinical , angiographic , and outcome variables between males and females . tlf survival analysis ( kaplan - meier ) was performed for both subgroups .
logistic regression analysis modeling for age , gender , obesity , diabetes , hypertension , lm lesions , renal insufficiency , number of stents per patient , and stent type was performed .
spss ( ibm , ny , usa ) software was used to conduct the analysis .
there were more males , smokers , obese patients , and a higher incidence of premature family history of coronary disease in the younger group .
the majority of both younger and older patients were still on dual antiplatelet agents on followup .
older patients had a nonsignificant trend for more left main and more vessels treated per patient , but otherwise angiographic variables appear to be similar between the 2 groups .
there was a high prevalence of treated bifurcating , left main , and ostial disease in both groups .   
the reasons for the index angiogram are listed in table 3 and appear to be similar in both younger and older patients .
the majority of patients were symptomatic with either acute coronary syndromes or chest pain with abnormal functional testing . a smaller percentage similar between the 2 groups had no symptoms and were treated for an abnormal functional test or as part of a staged procedure . despite the complex disease treated , angiographic success , defined as obtaining a residual stenosis of less than 30% , was achieved in all cases .   
at 2-year followup , the primary endpoint of tlf was 27.7% and 25.5% in both younger and older cohorts , respectively , ( p = 0.711 ) ( table 4 ) with no statistical difference in the secondary endpoints between tvf ( 36.0% versus 32.8% , p = 0.569 ) , tlr ( 24.8% versus 21.4% , p = 0.518 ) , cardiac death ( 3.4% versus 2.5% , p = 0.750 ) , definite and probable stent thrombosis ( 2.0% versus 1.0% ) , and nonfatal myocardial infarction ( 4.0% versus 4.5% , p = 0.475 ) .  
logistic regression analyses showed that renal failure ( p = 0.045 , odds ratio : 2.552 , 95% confidence interval : 1.021 to 6.381 ) , number of stents per patient ( p = 0.001 ; odds ratio : 1.603 , 95% confidence interval : 1.255 to 2.047 ) and to a lesser extent younger age ( p = 0.010 ; odds ratio : 0.969 , 95% confidence interval : 0.947 to 0.992 ) , but not gender , diabetes , or type of des stent ( ees versus pes ) predicted tlf .
several reports indicated that older age is an independent predictor of adverse events after pci with higher inhospital vascular complications and cardiac death [ 2 , 3 ] and higher long term cardiac mortality .
feldman et al .   reported the outcomes of pci patients in 3 age groups ( < 60 , 6080 , and > 80 years ) from the new state angioplasty registry .
older patients had more comorbidities with more extensive coronary disease , hypertension , peripheral vascular disease , and renal insufficiency . in the emergency pci group , there was an age - related incremental increase in inhospital mortality ( 1.0% versus 4.1% versus 11.5% , p < 0.05 ) and major adverse events ( 1.6% versus 5.2% versus 13.1% , p < 0.05 ) .
similarly , in those patients presenting for elective pci group , there was also an age - related incremental increase in mortality ( 0.1% versus 0.4% versus 1.1% , p < 0.05 ) , and adverse events ( 0.4% versus 0.7% versus 1.6% , p < 0.05 ) but to a lesser extent than emergency patients . in their series , multivariate analysis demonstrated that age was strongly predictive of inhospital mortality for all pci patients .
in addition , assali et al .   compared the outcomes of 266 consecutive patients 75 years with 1681 consecutive patients < 75 years of age undergoing nonemergent pci .
elderly patients had a higher length of hospital stay , more vascular complications , and bleeding complications .
multivariate analysis demonstrated that age 75 years was found to be an independent predictor of inhospital cardiac death ( odds ratio = 3.9 ; 95% ci = 1.311.5 ; p = 0.015 ) .   in our reports ,
cardiac mortality and tlr were not different between younger and older patients at 2-year followup .
there was a statistical increase in the odds ratio of tlr for younger patients , although the magnitude of this change was clinically insignificant .
et al .   reported in 1364 patients undergoing pci and stratified by age . in their cohort , and despite an increase in cardiac mortality in the elderly , the long term adverse events were similar between younger and older patients ( > 75 years ) .
similarly , xu et al .   reported in 333 patients undergoing pci that there were no differences in restenosis , tlr , stent thrombosis , bleeding , and stroke in younger versus older patients on followup at 7 months .
finally , rathore et al . reported no differences in procedural success , inhospital adverse cardiac events , and major adverse events at 1-year between younger ( < 65 years ) and older ( 65 years ) women undergoing pci .
in fact , similar to our data , older patients had less likely ischemia - driven revascularization at 1-year followup .
although we see a statistical reduction in the odds for tlf in older patients in our cohort , the magnitude of the change is small and likely to be clinically insignificant .
although elderly patients are more likely to have a higher cardiac mortality with long term followup , particularly when followup starts at an advanced age ( > 75 years or 80 years of age ) , there is no apparent disadvantage in revascularization of elderly patients compared to younger ones with respect to recurrent revascularization and tlf .
this data supports the conclusion that elderly patients need to be given the option of revascularization when feasible with expected tlf similar to the younger population .  
one of the limitations of this study is its relatively small size and its retrospective design .
the difference in tlf rates between the younger and older populations is , however , very small ( 2.2% ) and unlikely to be significant even with a much larger number of patients enrolled .
also , bias has been reduced by an unselected cohort of patients , and the data appears consistent with published outcomes in younger versus older patients in the current era of post - pci .
finally , we selected 65 years of age ( rather than 75 years ) to be the cutoff limit for defining an  older  population . whether our data can be extrapolated exclusively to patients over 75 years of age
we evaluate differences in outcomes in younger ( < 65 years ) and older ( 65 years ) patients for target lesion failure ( tlf ) at 2-year follow - up in an unselected consecutive series of patients treated with the everolimus- ( ees ) and paclitaxel - eluting ( pes ) stents at a tertiary medical center . 
 348 consecutive patients ( younger 150 ; older 198 ) stented with the ees and pes were retrospectively analyzed . 
 the primary endpoint was tlf ( composite endpoint of cardiac death , non fatal myocardial infarction due to index vessel and target lesion revascularization ( tlr ) ) . at 2 years 
 follow up , younger versus older patients had the following outcomes respectively : tlf 27.7% versus 25.5% ( p = 0.71 ) , tlr 24.8% versus 21.4% ( p = 0.52 ) , cardiac death 3.4% versus 2.5% ( p = 0.75 ) and definite and probable stent thrombosis ( 2.0% versus 1.0% ) . 
 multivariate analysis showed that renal failure ( odds ratio : 2.55 , p = 0.045 ) , number of stents per patient ( odds ratio : 1.60 , p = 0.001 ) and younger age ( odds ratio : 0.97 ; p = 0.010 ) , but not gender , diabetes or type of des stent ( ees versus pes ) predicted tlf . 
 we conclude that older age was not a predictor of tlf at 2-year follow - up after adjusting for renal insufficiency , number of stents used per patient , gender , diabetes and type of des used .