1- Population
During this study, we evaluated 24328 patients who underwent CABG in THC from 2007 to 2017. The mean age was 60.8 ± 9.52, 6428 (26.4 %) were women and 17900 (73.6%) were men. The mean age of patients increased from 60.7 ± 9.46 to 61.7 ± 9.5 and the male to female ratio remained nearly constant at approximately 2.8 (Table 1). The median follow-up duration was 78.1 months (76.31 to 79.87 months).
Table 1
Patients’ demographic characteristics in each 3 years
Year
|
Age
|
Sex
|
Coronary artery disease risk factors
|
HTN
|
DLP
|
DM
|
Cigarette smoking
|
Obesity
|
Opium addiction
|
Family History
|
2007–2010
|
60.7 ± 9.46
|
Male 73.2%
|
5210 (51.90%)
|
6201 (61.70%)
|
3491 (34.70%)
|
1645 (16.40%)
|
2361
(23.6%)
|
1122 (11.40%)
|
4278 (42.60%)
|
Female 26.8%
|
2011–2013
|
60.81 ± 9.53
|
Male 73.3%
|
2945 (48.30%)
|
3003 (49.20%)
|
2483 (40.70%)
|
961 (15.80%)
|
1366
(22.4%)
|
629 (10.80%)
|
2594 (42.50%)
|
Female 26.7%
|
2014–2017
|
61.7 ± 9.5
|
Male 74.3%
|
4760 (58.40%)
|
4387 (53.90%)
|
3363 (41.20%)
|
1656 (20.40%)
|
2017 (24.9%)
|
1509 (18.60%)
|
2449 (30.00%)
|
Female 25.7%
|
Total
|
60.8 ± 9.52
|
Male 73.6%
|
12915 (53.10%)
|
13591 (56.00%)
|
9337 (38.40%)
|
4262 (17.60%)
|
5744 (23.7%)
|
3260 (13.70%)
|
9321 (38.30%)
|
Female 26.4%
|
Data are presented as mean ± standard deviation and number (%) |
HTN: hypertension, DLP: dyslipidemia, and DM: diabetes mellitus |
2- Risk factor distribution
2 − 1. Total Population
We compared risk factors distribution in 3 time periods, 2007–2010, 2011–2013, and 2014–2017. In all of these periods, HTN and DLP were the most prevalent risk factors, present in more than half of the patients. Although not at a steady pace, HTN, DM, cigarette smoking, opium addiction tended to increase over the years. On the other hand, positive family history decreased significantly in the last period. As for DLP, despite a significant decrease in 2011–2013, it showed a slight increase in 2014–2017. Obesity remains nearly constant through the years being present in nearly a quarter of patients. In general, DLP (56.00%), HTN (53.10%), DM (38.40%), and positive family history (38.30%) were the most frequent risk factors in all patients (Table 1, Fig. 1).
2–2. Premature Population, Men vs. women
Based on the age of premature CAD in men and women, risk factors distribution was categorized into 4 groups, men ≤ 50 (2883; 11.9%), men > 50 (15018; 61.7%), women ≤ 55 (1448; 6.0%) and women > 55 (4979; 20.4%).
In premature CAD in men, DLP and positive family history were the most frequent risk factors, with DM and opium addiction being the least frequent ones. In men older than 50, DLP then HTN had the highest, and opium addiction and cigarette smoking had the lowest prevalence. Positive family history showed the biggest difference between the men of two age groups (52.6% in men ≤ 50 vs 33.2% in men > 50). In men of all ages, DLP (51.3%) and HTN (46.5%) were the most frequent risk factors. In women ≤ 55, DLP, HTN, DM, and positive family history were all present in more than 50% of patients being the most prevalent risk factors respectively. HTN, DLP, and DM had the highest prevalence in women > 55. Similar to men, positive family history prevalence had the highest difference between women of the age groups. HTN (72.3%), DLP (69.7%), and DM (55.4%) were the most prevalent risk factors in all women. In all age-sex groups, DLP was the most frequent risk factor except for women > 55 whose HTN was slightly higher than DLP. Both TG and LDL had a nearly declining trend in 2007–2016, with women ≤ 55 having the highest levels and men over 50 having the lowest levels. In comparison between men and women, HTN, DLP, DM, Obesity, and positive family history were all higher in women, all statistically significant. Cigarette smoking and opium addiction were significantly lower in the female group, present in less than 5% of the patients despite increasing prevalence over the years. (Table 2, Fig. 1).
Table 2
Risk factors distribution in each age-sex group
Age-sex category
|
Coronary artery disease risk factors
|
Hypertension
|
Dyslipidemia
|
Diabetes mellitus
|
Cigarette smoking
|
Obesity
|
Opium addiction
|
Family History
|
Men ≤ 50
|
1023 (35.50%)
|
1620 (56.30%)
|
708 (24.60%)
|
998 (34.60%)
|
775 (27.0%)
|
734 (25.90%)
|
1517 (52.60%)
|
Men > 50
|
7269 (48.50%)
|
7513 (50.10%)
|
5081 (33.90%)
|
3080 (20.60%)
|
2562 (17.1%)
|
2394 (16.40%)
|
4986 (33.20%)
|
Women ≤ 55
|
930 (64.30%)
|
1008 (69.70%)
|
844 (58.30%)
|
56 (3.90%)
|
646 (44.7%)
|
44 (3.00%)
|
803 (55.50%)
|
Women > 55
|
3693 (74.30%)
|
3450 (69.50%)
|
2704 (54.40%)
|
128 (2.60%)
|
1761 (35.6%)
|
88 (1.80%)
|
2015 (40.50%)
|
Men
|
8292 (46.4%)
|
9133 (51.1%)
|
5789 (32.3%)
|
4078 (22.8%)
|
3337 (18.7%)
|
3128 (17.8%)
|
6503 (36.3%)
|
Women
|
4623 (72.0%)
|
4458 (69.5%)
|
3548 (55.2%)
|
184 (2.8%)
|
2407 (37.6%)
|
132
(2.0%)
|
2818 (43.8%)
|
P-value⁎
|
< 0.001
|
< 0.001
|
< 0.001
|
< 0.001
|
< 0.001
|
< 0.001
|
< 0.001
|
Data are presented as mean ± standard deviation and number (%) |
⁎ Men vs women risk factor distribution difference, statistically significant values are bolded |
3- Long term outcome, Men vs. Women
We evaluated patients’ post-CABG prognosis based on our follow-up data and compared the results in different age-sex groups. Men under 50 had the best survival (93.6%) and least incident of MACE (20.8%). Worst survival observed in female patients older than 55 (83.4%) who also had the highest incident of MACE (30.6%). In comparison, men had better survival than women (86.2% vs. 84.9%) with fewer MACE incidents (24.6% vs 29.7%) which both were statistically significant. In general, patients had 85.9% overall survival and 74.1% of them survived without any MACE (Table 3). We used the Kaplan-Meyer method to draw age-sex group survival plots. As for overall survival men ≤ 50, women ≤ 55, men > 50, and women > 55 had the best to worst survival respectively. Men > 50 and women > 55 survival declined greater than those with premature CAD after CABG. In terms of MACE incident men, ≤ 50 had the best and women > 55 had the worst MACE-free survival and men > 50 and female ≤ 55 had near-identical plot after surgery (Fig. 2)
Table 3
Overall survival and survival without major adverse cardiovascular events after CABG
Age-sex category
|
Overall survival
|
MACE-free survival
|
Men ≤ 50
|
93.6%
|
79.2%
|
Men > 50
|
84.80%
|
74.70%
|
Women ≤ 55
|
90.5%
|
73.6%
|
Women > 55
|
83.4%
|
69.4%
|
Men
|
86.2%
|
75.4%
|
Women
|
84.9%
|
70.3%
|
P-value⁎
|
0.013
|
< 0.001
|
Total
|
85.9%
|
74.1%
|
MACE: major adverse cardiovascular event |
⁎ Men vs women risk factor distribution difference, statistically significant values are bolded |
Finally, we compared men and women in the number of CADRFs. Near half of the patients had 3 or more risk factors and on average female patients had slightly more risk factors. (Fig. 3)