Long-Term Benefit and Withdrawal Effect of Statins After Percutaneous Coronary Intervention: A Nationwide Population-Based Cohort Study

Figures & data

Figure 1 Examples of the definition of risk periods according to statin treatment.

Abbreviation: PCI, percutaneous coronary intervention.

Table 1 Clinical Characteristics of Patients Who Received Percutaneous Coronary Intervention

Variable	[All] N = 5218
Sex, male	3402 (65.2)
Age	60–64 [50–54; 70–74]
Hypertension	4511 (86.5)
Diabetes mellitus	1742 (33.4)
Atrial fibrillation	436 (8.4)
Myocardial infarction	2380 (45.6)
Household Income
Low	1535 (29.4)
Middle	1908 (36.6)
High	1775 (34.0)
Year of Admission
2002–2005	1059 (20.3)
2006–2009	1805 (34.6)
2010–2013	2354 (45.1)

Note: Data are number (%) or median [interquartile range].

Table 2 Result of Cox Regression Analyses for Primary Outcome After Percutaneous Coronary Intervention

Variable	Univariate		Multivariate
	Unadjusted HR [95% CI]	p-value	Adjusted HR [95% CI]	p-value
Time-fixed variables
Sex, male	0.98 [0.88–1.08]	0.646	1.06 [0.95–1.19]	0.292
Age, per 5 years	1.07 [1.05–1.10]	< 0.001	1.07 [1.04–1.10]	< 0.001
Hypertension	1.09 [0.93–1.27]	0.302	1.02 [0.87–1.20]	0.082
Diabetes mellitus	1.34 [1.20–1.48]	< 0.001	1.33 [1.19–1.47]	< 0.001
Atrial fibrillation	1.27 [1.08–1.50]	< 0.001	1.16 [0.98–1.37]	0.090
Myocardial infarction	1.42 [1.28–1.57]	< 0.001	1.42 [1.29–1.58]	< 0.001
Household Income
Low	1 (Ref)	–	1 (Ref)	–
Middle	0.99 [0.87–1.12]	0.863	1.03 [0.91–1.17]	0.637
High	1.05 [0.92–1.19]	0.456	1.08 [0.95–1.23]	0.243
Time-dependent Variables
Antiplatelets
No aspirin, no ADPRB	1 (Ref)	–	1 (Ref)	–
Aspirin only	0.49 [0.42–0.57]	< 0.001	0.71 [0.59–0.85]	< 0.001
ADPRB only	0.58 [0.46–0.72]	< 0.001	0.82 [0.64–1.05]	0.120
Aspirin plus ADPRB	0.69 [0.60–0.80]	< 0.001	1.03 [0.86–1.23]	0.730
Statins
No statin	1 (Ref)	–	1 (Ref)	–
Statin use	0.69 [0.62–0.78]	< 0.001	0.72 [0.63–0.81]	< 0.001
Withdrawal	1.90 [1.56–2.32]	< 0.001	1.87 [1.52–2.29]	< 0.001

Note: Data are derived from multivariate time-dependent Cox proportional hazard regression model.

Abbreviations: ADPRB, adenosine diphosphate receptor blocker (clopidogrel, prasugrel, ticlopidine, ticagrelor); CI, confidence interval; HR, hazard ratio.

Table 3 Secondary Outcome Analysis for Individual Outcome

Event of Interest	Myocardial Infarction	Coronary Revascularization	Stroke	All-Cause Death
Risk period
No statin	1 (Ref)	1 (Ref)	1 (Ref)	1 (Ref)
Statin use	0.84 [0.64–1.11]	0.79 [0.66–0.94]	0.73 [0.33–1.61]	0.44 [0.34–0.58]
Withdrawal	2.11 [1.39–3.20]	2.43 [1.81–3.26]	0.78 [0.55–1.12]	1.49 [1.02–2.18]

Notes: Data are adjusted hazard ratio [95% confidence interval] derived from multivariate time-dependent Cox proportional hazard regression models for individual outcomes. Adjustments were performed for same variables listed in Table 2.

Figure 2 Risk for primary outcome according to statin treatment. (A) Adjusted HR for “statin use period” and “withdrawal period” compared to the “no statin period” (Ref). (B) Adjusted HR for statin withdrawal for “low-intensity”, “moderate-intensity”, and “high-intensity” statins compared to the “no statin period” (Ref). Data are derived from multivariate time-dependent Cox proportional hazard regression analysis adjusted for the variables listed in Table 2

Abbreviations: CI, confidence interval; HR, hazard ratio.