Microbiocenosis-correcting approaches to personalized complex therapy of Parkinson’s disease patients

Parkinson’s disease (PD) is a socially significant neurodegenerative disorder characterized by dysbiotic imbalances in intestinal microbiome.

The aim: to evaluate the effect of personalized combination therapy for PD based on an assessment of gastrointestinal microbiome and its correlation with iron, hemoglobin, cyanocobalamin, and folate metabolism, as well as cognitive status.

Material and methods. 112 patients with PD (aged 50–85 years) and 52 healthy volunteers were examined. A cohort of 60 patients (n = 60) was randomized into two groups: Group 1 received metronidazole and a probiotic (Bifiform) along with standard PD therapy; Group 2 (n = 30) received standard therapy alone. Participants were assessed for fecal microbiome, iron metabolism parameters, vitamin B9 and B12 levels, and neuropsychological scale scores (HADS, MoCA, 3-KT, MDS-UPDRS, MOSCOW).

Results. Desulfovibrio spp. bacteria were detected in 73.3% of PD patients and only in 1.9% of healthy control participants (p <0.001). With intestinal cleansing, patients showed improvements in HADS (decreased anxiety/depression) and MoCA (increased mean score; decreased proportion of patients with moderate cognitive impairment) scales’ indexes. According to the 3-CT scale, patients with PD showed significant improvements in semantic and phonetic associations, clock drawing, and recall tests. More than 90% of PD patients had baseline iron deficiency (median 8.4 vs. 13.1 μmol/L in healthy individuals; p <0.001), and they were also more likely to have low blood levels of vitamins B₉ and B₁₂. After the treatment, patients in Group 1, who received metronidazole and a probiotic in addition to standard PD therapy, showed statistically significant increases in hemoglobin, iron, and B₉ levels. Furthermore, the proportion of patients with vitamin B₆, B₁₂, and iron deficiencies in this study group was statistically significantly reduced.

Conclusion. High Desulfovibrio spp. levels in case of PD and their reduction with targeted therapy are accompanied by clinical and metabolic improvements in patients having such kind of disease.