During the progression of the movement disorder, older patients with Parkinson disease may see changes in their insulin-like growth factor and serum homocysteine indices but a potential therapy could improve these factors.
Newly published BMC Neurology, a study on patients with mid-late Parkinson disease (PD) who received resagiline in combination with levodopa and benserazide hydrochloride demonstrated significant positive therapeutic effects. In the trial, treatment with the combination therapy significantly reduced patient’s serum levels of homocysteine (Hcy), raised insulin-like growth factor (IGF-1) levels, and improved motor performance.1
After 1-year on the combination therapy, investigators observed a significantly higher total effective rate in the clinical observation group (n = 32) in comparison with controls (n = 32) (93.75%; 68.75%; P <.05, respectively). At the same time, investigators observed decreases in both groups on Unified Parkinson’s Disease Rating Scale (UPDRS) score although the observation group had significantly lower scores than the control group (P<.05). Notably, following treatment, both groups experienced decreases in serum Hcy and IGF-1; however, the observation group had higher mean levels compared with the control group (P<.05).
“The latest results of this study showed that through about 1 year of combined drug and rehabilitation therapy, the H-Y classification and UPDRS scores of the patients in the observation group were significantly lower than those of the control group, and the UPDRS III scores of the patients in the observation group were all significantly lower than those of the control group,” lead author Yifan Yang, MD, department of neurology, Affiliated Hospital of Southwest Jiaotong University & Chengdu Third People's Hospital, in Sichuan, China, and colleagues wrote.1 “This suggests that relative to levodopa therapy alone, the addition of rasagiline adjuvant therapy to levodopa is more effective in improving the motor function of patients with PD, reducing the incidence of end-of-agent fluctuations of motor complications, and leading to a significant improvement in the motor function of patients with PD.”
Investigators gathered data from over 168 cases of patients with PD who were over 60 years old in the middle and late stages of PD between June 2020 and December 2021. These patients were seen in the outpatient and inpatient departments of the Third People's Hospital of Chengdu City and had a detailed observation record. The authors randomly and evenly grouped 64 patients who met the inclusion criteria into a clinical observation group and a control group, each with 32 patients. Those in the control group received only levodopa and benserazide hydrochloride treatment, while the observation group was treated with resagiline in combination with the clinical control group. The motor function and serum Hcy and IGF-1 indexes of both groups were compared after the end of 1 year on treatment.
“The results of this analysis showed that after 1 year of treatment, the degree of hcy reduction in patients in the observation group was significantly better than that in the control group, and the differences were all statistically significant, which may be explained by the neuronal protective function of resagiline, a drug that also prevents dopamine neurons from Hcy-mediated oxidative stress damage,” Yang et al noted.1 “The results of this study showed that the serum IGF-1 level in the observation group was significantly higher than that before treatment, and the difference was statistically significant, which may be because of the fact that the combination of resagiline can inhibit the regulatory function of monoamine oxidase B, thus enhancing the release of dopamine in the body and blocking the uptake of dopamine, which plays a role in protecting dopaminergic neurons.”
The authors noted that it is important to consider that the collection of this clinical information was limited and thus, further extensive clinical follow-up is needed to confirm these findings. Additionally, investigators recommended that the information gathered from this study should be expanded to draw out any clinical symptomatic targets and impacts in more depth.