Transcranial midbrain sonography and depressive symptoms in patients with Parkinson's disease

Transcranial sonography (TCS) appeared to be a promising marker associated with depression: hypo/anechogenicity of the brainstem raphe (BR) was found in 50-70 % of patients with unipolar depression, in 40-60 % of depressed patients with Parkinson's disease (PD), but also in 8-28 % of healthy controls. Our study included 120 consecutive PD outpatients. Abnormal BR echogenicity was found in 51 (43 %), while normal findings were present in 67 PD patients (57 %). Patients with abnormal BR echogenicity had higher scores on the Montgomery-Asberg Depression Rating Scale (MADRS) items of apparent sadness (p = 0.03), reported sadness (p = 0.01), and pessimistic thoughts (p = 0.049), when compared to those with normal BR. In the second part of the study, previously suggested cut-off value at 14/15 on the MADRS was used to dichotomize patients into depressed (dPD) (46 patients; 39 %) and non-depressed PD patients (ndPD) (72 patients; 61 %). Abnormal TCS BR findings were obtained in 27 dPD (58.7 %) and in only 24 ndPD patients (33.3 %) (p = 0.007): the risk that PD patients with the TCS BR abnormality would display depressive symptoms was about 3.5 times higher when compared to PD patients with intact BR, controlling for the effect of motor difficulties (cross-odds ratio; OR = 3.48). Therefore, at least in a subgroup of dPD patients, TCS of the midbrain midline structure may potentially be a useful tool for depressive symptoms prediction.