Prevalence of risk factors at presentation and early mortality in patients aged 80 years or older with ST-segment elevation myocardial infarction

Figures & data

Figure 1 Flow chart of the exposed/nonexposed cohort design.

Abbreviations: AMI, acute myocardial infarction; STEMI, ST-segment elevation myocardial infarction; NSTEMI, non-ST-segment elevation myocardial infarction; D, in-hospital mortality yes (+) or no (−).

Table 1 Patient characteristics at admittance

Characteristics	<80 years (n=3,556)	≥80 years (n=536)	P-value*
Male, n (%)	2,822 (79.4)	266 (49.6)	<0.001
Current smokers, n (%)	1,727 (48.6)	70 (13.1)	<0.001
Treated hypertension, n (%)	1,154 (32.5)	263 (49.1)	<0.001
Diabetes mellitus, n (%)	435 (12.3)	75 (14.0)	0.257
Prior hyperlipidemia, n (%)	420 (11.8)	40 (7.5)	0.003
Family history, n (%)	617 (17.5)	11 (2.1)	<0.001
Prior myocardial infarction, n (%)	478 (13.5)	123 (22.9)	<0.001
Prior percutaneous coronary intervention, n (%)	387 (10.9)	46 (8.6)	0.104
Prior stroke, n (%)	154 (4.3)	72 (13.5)	<0.001
Prior peripheral vascular disease, n (%)	121 (3.4)	44 (8.2)	<0.001
Prior angina, n (%) laboratory values†	266 (7.5)	97 (18.1)	<0.001
Creatinine, μmol/L	73 (62–105)	88 (72–110)	<0.001
Total cholesterol, mmol/L	4.8 (4.1–5.6)	4.7 (3.8–5.7)	0.024

Notes:

* Chi-square test for categorical variables. Mann–Whitney test for continuous variables;

† median with 25th and 75th percentile.

Table 2 Risk for in-hospital mortality in patients 80 years old and older versus those younger than 80 years, showing variables with significant confounding effect and effect modifiers in the stratification analysis

Variable level	OR (95% CI)	ORM-H (95% CI)	C%	P-value*
Prior angina
Yes	3.06 (1.43–6.53)	5.16 (3.84–6.95)	5.4	0.1233
No	5.84 (4.25–8.03)
Current smoker
Yes	7.82 (3.57–17.09)	4.10 (3.03–5.55)	24.2	0.0996
No	3.84 (2.78–5.30)
Creatinine, μmol/L
>84	3.04 (2.06–4.47)	†	Effect modifier	0.0025
<84	7.60 (4.86–11.89)
Cholesterol, mmol/L
>4.8	10.67 (5.86–19.40)	†	Effect modifier	0.0054
<4.8	4.01 (2.85–5.65)

Notes: Variables included that did not show any confounding effect on in-hospital mortality: sex, diabetes mellitus, treated hypertension; prior hyperlipidemia, family history, prior MI, prior percutaneous coronary intervention, prior stroke, and prior peripheral vascular disease. Crude OR was 5.41 (95% confidence interval, 4.04–7.24); confounder effect % = [[OR_M-H – ORc]/ORc] ×100.

* Heterogeneity test across strata, Breslow-Day test; P<0.05= effect modifier;

† we cannot estimate an adjusted OR_M-H in the presence of effect modification.

Abbreviations: C%, confounder effect percentage; CI, confidence interval; MI, myocardial infarction; OR, odds ratio; OR_M-H, Mantel-Haenszel adjusted OR.

Table 3 Adjusted risk for in-hospital mortality in patients 80 years old and older versus those younger than 80 years, controlling for the confounding effect of smoking and for the two effect modifiers, serum cholesterol and creatinine

Creatinine, μmol/L*	Cholesterol, mmol/L†	Odds ratio‡	95% confidence interval	P-value
63	4.1	3.01	1.86–4.93	0.0001
110	4.1	4.15	2.69–6.40	0.0001
63	6.4	8.50	3.80–19.20	0.0001
110	6.4	11.72	5.26–26.13	0.001

Notes: Variables included that did not show any confounding effect on in-hospital mortality: sex, diabetes mellitus, treated hypertension; prior hyperlipidemia, family history, prior myocardial infarction, prior percutaneous coronary intervention, prior stroke, and prior peripheral vascular disease. Crude odds ratio was 5.41 (95% confidence interval, 4.04–7.24).

* 63 μmol/L and 110 μmol/L =25th and 90th percentiles of creatinine, respectively;

† 4.1 mmol/L and 6.4 mmol/L =25th and 90th percentiles of cholesterol, respectively;

‡ logistic regression analysis.

Figure 2 Adjusted odds ratio (OR) of in-hospital mortality for patients 80 years old and older vs those younger than 80 years in relation to creatinine levels, controlling for smoking habits and for the median level of serum cholesterol (4.8 mmol/L).

Notes: OR curve with 95% confidence interval lower and upper bound. Points represent, from left to right, 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles.

Figure 3 Adjusted odds ratio (OR) of in-hospital mortality for patients 80 years old and older vs those younger than 80 years in relation to total cholesterol levels, controlling for smoking habits and for the median level of serum creatinine (84 μmol/L).

Notes: OR curve with 95% confidence interval lower and upper bound. Points represent, from left to right, 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles.