CHRM4 and depressive symptom measurement: Lastly, SBI patients who reported depression had significantly lower median titers of anti-α2AR (10.3 vs. 14.2, p < 0.001), anti-AT1R (10 vs. 11, p = 0.012), anti-β1AR (8 vs. 11, p = 0.003), anti-β2AR (5.1 vs. 7.5, p = 0.047), anti-ETAR (7.7 vs. 9.3, p = 0.017), anti-M1R (2.13 vs. 3.05, p = 0.021), anti-M2R (3 vs. 4, p < 0.001), anti-M3R (5.9 vs. 7.7, p = 0.026), anti-M4R (5 vs. 9, p < 0.001), and anti-M5R (6.3 vs. 7.6, p = 0.023) in comparison to SBI patients who did not report depression (Figure 4 and Table 4).