The results revealed that MDS-UPDRS, MDS-UPDRS II, MDS-UPDRS IV, PDQ-39, Escherichia coli/Lactobacillus ratio, fecal lactoferrin, and fecal calprotectin were independent risk factors for the decline in treatment efficacy in Parkinson’s disease patients (all p < 0.05). This evidence concerns the gene LTF and Parkinson disease.