Accounting for the mortality benefit of drug-eluting stents in percutaneous coronary intervention: a comparison of methods in a retrospective cohort study
Key result
A stent era comparison showed no significant difference in 1-year mortality between drug-eluting stents and bare metal stents (OR 0.92), suggesting prior observational benefits were due to unmeasured confounding.
Why the study?
Do drug-eluting stents reduce all-cause mortality and myocardial infarction in patients undergoing percutaneous coronary intervention compared to bare metal stents?
Population
35,438 patients undergoing percutaneous coronary intervention with stenting in a large, integrated health…
Comparison
Drug-eluting stents (DES) vs Bare metal stents (BMS)
Design
Cohort
Follow-up
30 days and 1 year
Authors
Discussion
Loading...
Member takes
Implication
No mortality difference supports equipoise in stent selection; challenges prior observational benefits and leaves open randomized confirmation.
Study Design
Type
Cohort (n=35,438)
Multicenter
Yes
Structured PICO
Do drug-eluting stents reduce all-cause mortality and myocardial infarction in patients undergoing percutaneous coronary intervention compared to bare metal stents?
P
Population
35,438 patients undergoing percutaneous coronary intervention (PCI) with stenting in a large, integrated health system between 1998 and 2007
I
Intervention
Drug-eluting stents (DES)
C
Comparator
Bare metal stents (BMS)
O
Outcome
Short-term rates of all-cause mortality and myocardial infarction (at 30 days and one year)hard clinical
Main Result
Effect estimate: OR 0.92 (95% CI 0.82 - 1.02)
p-value: p=0.12
The apparent mortality benefit of drug-eluting stents over bare metal stents in observational studies is likely due to unmeasured confounding by indication rather than a true biological effect, as demonstrated by stent era comparisons.
Limitations
- Potential for unmeasured variables that confound results in observational studies
- Stent era comparison compares patients at two different times, meaning secular trends may have influenced the results
- Residual confounding in propensity-score adjustment and matching due to strong treatment selection
- Unobserved factors influencing stent selection (confounding by indication)
Cite This Study
Yeh et al. (2011) conducted a cohort in Percutaneous coronary intervention (n=35,438). Drug-eluting stents vs. Bare metal stents was evaluated on All-cause mortality at 1 year (stent era comparison) (OR 0.92, 95% CI 0.82 - 1.02, p=0.12). A stent era comparison showed no significant difference in 1-year mortality between drug-eluting stents and bare metal stents (OR 0.92), suggesting prior observational benefits were due to unmeasured confounding.