## 3 Results
### Patient Demographic and Clinical Data
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Characteristics** & **Value** \\ \hline \multicolumn{3}{c}{Clinical factors} \\ \multicolumn{3}{c}{Preoperative Hemoglobin (g/l)} & 141.0 (131.0–152.0) \\ \multicolumn{3}{c}{Ejection Fraction (\%)} & 55.0 (45.0–60.0) \\ \multicolumn{3}{c}{EuroSCORE-II} & 1.1 (0.7–2.0) \\ \multicolumn{3}{c}{Eutubating time (ET)} & 7.0 (5.0–10.0) \\ \multicolumn{3}{c}{On pump} & 193 (91.0) \\ \multicolumn{3}{c}{Extracorporeal Circulation length} & 79.5 (63.0–98.3) \\ \multicolumn{3}{c}{Number of grafts} & 3.0 (2.0–3.0) \\ \multicolumn{3}{c}{Postoperative hospital LOS (days)} & 8.0 (7.0–10.0) \\ \multicolumn{3}{c}{Binary postoperatively hospital LOS values} \\ \(\leq\)7 days & 88 (41.5) \\ \(>\)7 days & 124 (58.5) \\ \multicolumn{3}{c}{Intensive care unit LOS, days} & 2.0 (2.0–3.0) \\ \multicolumn{3}{c}{Postoperative atrial fibrillation} & 44 (20.8) \\ \multicolumn{3}{c}{Infection} & 13 (6.1) \\ \multicolumn{3}{c}{Preoperative CRP} & 2.3 (1.0–4.7) \\ \multicolumn{3}{c}{Early CRP Change score} & 107.2 (86.8–146.9) \\ \multicolumn{3}{c}{Persistent CRP Change score} & 68.5 (51.9–90.9) \\ \multicolumn{3}{c}{Depression symptoms} \\ \multicolumn{3}{c}{Total BDI-II scores} & 8.0 (5.0–11.0) \\ \multicolumn{3}{c}{Binary BDI-II scores} \\ \multicolumn{3}{c}{None (\(\leq\)13)} & 186 (87.7) \\ \multicolumn{3}{c}{Mild to Severe (>13)} & 26 (12.3) \\ \hline \end{tabular} Data are presented as counts (n) and percentages (%) for categorical variables and as mean \(\pm\) standard deviation (SD) or median and interquartile range (IQR) for continuous variables. ACE, Angiotensin-converting enzyme; BMI, body mass index; CRP, high-sensitivity C-reactive protein; BDI-II, the Beck Depression Inventory; ICU, intensive care unit; LOS, length of stay.  
\end{table} 
Table 1: _Cont._ \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Characteristics** & **BDI-II \(\leq\) 13** & **BDI-II \(>\) 13** & _p_**-Value** \\ \multicolumn{3}{c}{**N = 186**} & **N = 26** & _p_-Value** \\ \hline \multicolumn{3}{c}{Age (years)} & 61.6 \(\pm\) 7.9 & 61.9 \(\pm\) 8.7 & 0.850 \\ \multicolumn{3}{c}{Gender (male)} & 154 (82.8) & 17 (65.4) & 0.059 \\ \multicolumn{3}{c}{Smoking (yes)} & 24 (13.0) & 8 (30.8) & 0.026 \\ \multicolumn{3}{c}{BMI (kg/m\({}^{2}\))} & 28.2 (25.7–30.7) & 28.4 (25.6–31.8) & 0.672 \\ \multicolumn{3}{c}{Baseline medications} \\ \multicolumn{3}{c}{Beta-blockers} & 160 (86.5) & 19 (76.0) & 0.224 \\ \multicolumn{3}{c}{Acetylsalicylic acid} & 165 (88.7) & 22 (84.6) & 0.521 \\ \multicolumn{3}{c}{AC inhibitors} & 114 (61.3) & 18 (69.2) & 0.520 \\ \multicolumn{3}{c}{Statin medications} & 169 (91.4) & 22 (88.0) & 0.480 \\ \multicolumn{3}{c}{Antidepressants} & 2 (1.1) & 0 (0.0) & \textgreater{}0.999 \\ \multicolumn{3}{c}{Medical history} \\ \multicolumn{3}{c}{Hyperfrehension} & 163 (87.6) & 22 (84.6) & 0.752 \\ \multicolumn{3}{c}{Diabetes} & 63 (33.9) & 14 (53.8) & 0.053 \\ \multicolumn{3}{c}{Hyperlipidemia} & 141 (75.8) & 18 (69.2) & 0.630 \\ \multicolumn{3}{c}{Family history of cardiovascular diseases} & 118 (64.1) & 14 (53.8) & 0.386 \\ \multicolumn{3}{c}{Preoperative MI} & 93 (50.0) & 17 (65.4) & 0.150 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Association between BDI-II depression symptom scores and patients’ demographic and clinical data. The prolonged postoperative hospital LOS was significantly associated only with older age at admission (t = 4.301, \(p\) < 0.001), lower preoperative hemoglobin levels (Mann-Whitney U test, \(p\) < 0.001), higher EuroSCORE II (Mann-Whitney U test, \(p\) < 0.001), persistent CRP change (Mann-Whitney U test, \(p\) < 0.001), and higher frequency of postoperative atrial fibrillation (\(\chi^{2}\) = 12.45, \(p\) < 0.001) (Table 3).