A total of 5,469 AIS patients were identified. In this population, 1,608 patients were eligible for rtPA and 1,327 of these received rtPA (Table 1). Of the patients treated with rtPA, 630 were taking a cholesterol reducer prior to the event, whereas 687 were not. As presented in Table 1, the rtPA treated subset of patients were younger (65.8 ± 14.8 vs. 67.7 ± 14.7), more likely to be Hispanic (2.3% vs. 1.3%) and have a higher BMI (28.18 ± 7.01 vs. 28.84 ± 6.84). This group presented with lower rates of carotid stenosis (4.2% vs. 6.7%) and diabetes (31.3% vs. 36.7%) but had higher rates of depression (15.4% vs. 12.5%) and dyslipidemia (52.8% vs. 49.6%). Furthermore, the rtPA group was more likely to be on HRT (2.3% vs. 1.2%), suffer from migraines (3.4% vs. 2.1%), and be obese (51.1 vs. 39.4). This group presented with fewer prior strokes (21.9% vs. 27.4%), but a greater history of TIAs (10.8 vs. 8.1%). They were less likely to have PVD (6.0% vs. 7.7%) and chronic renal disease (6.0% vs. 8.9%) but were more likely to be taking cholesterol reducing agents (47.6% vs. 43.4%) and antidepressants (16.7% vs. 11.8%). The rtPA group was taking fewer antidiabetic medications (24.9% vs. 28.1%) and presented with higher NIHSS scores (9.95 ± 6.6 vs. 7.82 ± 6.8). This group also presented with lower levels of serum cholesterol (168.7 ± 46.5 mg/dL vs. 173.0 ± 53.6 mg/dL), creatinine concentrations (1.14 ± 0.75 mg/dL vs. 1.34 ± 1.27 mg/dL), and blood glucose (141.3 ± 74.8 mg/dL vs. 149.2 ± 82.9 mg/dL) when compared to the non rtPA group. Moreover, the rtPA group differed significantly on ambulation classification prior to stroke, on admission, and on discharge. Patients in the rtPA group were more likely to be directly admitted to the hospital (23.4% vs. 19.9%) and have an improved ambulatory status (55.3% vs. 29.7%).
Table 2 shows the clinical and demographic characteristics associated with improving or worsening neurologic functions for patients who received rtPA and previously used cholesterol reducers versus those who didn’t have a history of cholesterol reducer therapy. In the rtPA with prior cholesterol reducer use group, patients with worsening neurologic functions were older (70.83 ± 13.26 vs. 65.95 ± 12.09), less likely to be Caucasian (86.3% vs. 79.0%), and more likely to be female (51.5% vs. 40.5%), with higher rates of atrial fibrillation (23.9% vs. 11.5%) and heart failure (15.2% vs. 9.7%). This group presented with lower rates of a family history of stroke (7.1% vs. 14.0%) and obesity (47.2% vs. 58.3%). For laboratory values, the group with worsening neurologic functions who received rtPA presented with higher blood glucose levels (147.04 ± 73.66 vs. 136.22 ± 63.35), higher international normalized ratio (INR) (1.07 ± 0.12 vs. 1.04 ± 0.12) and were more likely to be directly admitted to the hospital (84.5% vs. 67.3%). For the rtPA without prior cholesterol reducer use group, the patients with worsening neurologic functions were older (66.31 ± 15.82 vs. 59.67 ± 15.47), presented with lower BMI (27.83 ± 6.24 vs. 29.07 ± 6.72), higher rates of heart failure (10.8% vs. 5.2%), hypertension (71.1% vs. 59.5%), and were more likely to be taking anti-hypertensive (anti-HTN) medications (56.7% vs. 49.0%). This group presented with lower rates of a family history of stroke (6.3% vs. 12.7%), migraines (2.1% vs. 6.2%), obesity (45.4% vs. 56.2%) smoking history (29.1% vs. 38.2%) and triglycerides (128.33 ± 95. vs. 153.54 ± 119.4), but higher serum creatinine (1.16 ± 1.04 vs. 1.04 ± 0.4) and higher INR (1.07 ± 0.18 vs. 1.04 ± 0.15). In addition, this group presented with a higher heart rate (84.98 ± 18.94 vs. 80.71 ± 16.21) and were more likely to be directly admitted to the hospital (82.2% vs. 72.2%).
The forest plot demonstrating clinical factors that were associated with the severity of stroke for the total ischemic stroke population (Figure 1). In the adjusted analysis, increasing age (OR = 1.03, 95% CI, 1.019-10.4, P <0.001) and being female (OR = 1.369, 95% CI, 1.048-1.787, P =0.021) were variables associated with worsening neurologic functions, while dyslipidemia (OR = 0.709, 95% CI, 0.541‐0.927, P = 0.012), obesity (OR = 0.745, 95% CI, 0.572‐0.971, P = 0.029), direct admission (OR = 0.466, 95% CI, 0.324‐0.670, P <0.001), and Caucasian race (OR = 0.589, 95% CI, 0.42‐0.828, P = 0.002) were associated with improving neurologic functions. The discriminating capability of the model was moderately strong as shown by the ROC curve (Figure 2), with area under the curve (AUROC) = 0.677 (95% CI, 0.646–0.707, P < 0.001). In the rtPA group without prior cholesterol reducer use (Figure 3) increasing age (OR = 1.027, 95% CI, 1.014‐1.041, P < 0.0.01), higher heart rate (OR=1.016, 95% CI, 1.005-1.027, P=0.005), and improvement in ambulation (OR=1.571, 95% CI, 1.078-2.289, P =0.019) were associated with neurologic deterioration or worsening neurologic functions. Patients with a family history of stroke (OR=0.511, 95% CI, 0.264-0.99, P =0.047), migraines (OR=0.250, 95% CI, 0.130-0.943, P =0.038), obesity (OR = 0.685, 95% CI, 0.473‐0.992, P = 0.045), direct admission (OR=0.512, 95% CI, 0.303-0.866, P =0.013), and Caucasian race (OR = 0.604, 95% CI, 0.381‐0.957, P = 0.032) were more likely to be associated with a neurologic improvement. As presented in Figure 4, the predictive power of the logistic regression was moderately strong, as the area under the curve (AUROC) was 0.681 (95% CI, 0.637–0.724, P < 0.001). For the rtPA group with prior cholesterol reducer use (Figure 5), increasing age (OR = 1.032, 95% CI, 1.015-1.048, P < 0.001) and atrial fibrillation (OR = 1.859, 95% CI, 1.098-3.149, P = 0.021) were more likely to be associated with worsening neurologic function. Direct admission (OR = 0.411, 95% CI, 0.246-0.686, P = 0.001) and Caucasian race (OR = 0.496, 95% CI, 0.297-0.827, P = 0.007) were associated with greater neurologic improvement. The ROC curve for the predictive power of the regression model as presented in Figure 6 shows that the discriminating capability of the model was moderately strong, with the area under the curve (AUROC) = 0.680 (95% CI, 0.639–0.722, P < 0.001).