Patients who were followed for more than 5 years after truncal vagotomy had about a 40% lower risk of being diagnosed with Parkinson’s disease, compared with matched population controls, according to the results of a cohort registry study.
Selective vagotomy did not decrease the risk of Parkinson’s disease (PD), however, reported Bojing Liu of Karolinska Institutet, Stockholm, and her associates. The findings, which reflect those from a prior Danish study, “provide preliminary and indirect support” for the idea that Lewy pathology in PD begins in peripheral nerves and spreads to the central nervous system through “prion-like mechanisms,” they added.
The findings reflect a prior registry study that found a 15% decrease in the risk of PD compared with the general population more than 5 years after truncal vagotomy (). “This Danish study, however, did not differentiate truncal from selective vagotomy and thus might have underestimated the association of truncal vagotomy with PD,” the researchers said.
Another study found that truncal vagotomy exhibited a nonsignificant protective effect overall and an insignificantly increased risk of PD more than 20 years after surgery (). Likewise, the current study yielded “stronger evidence for PD risk reduction more than 5 or 10 years after truncal vagotomy,” and the protective effect appeared to weaken with longer follow-up, the investigators noted. If PD started at multiple sites within the peripheral nervous system, “even truncal vagotomy may delay, rather than eliminate, the risk for PD,” they emphasized. “Indeed, abnormal alpha-synuclein accumulation has been found throughout the digestive tract of patients with PD with descending pattern of density, and even in the submandibular gland in patients with preclinical PD.”
The study was funded by the Swedish Research Council for Health, Working Life and Welfare, the Parkinson Research Foundation in Sweden, the Karolinska Institutet, the Swedish Society for Medical Research, the Stockholm County Council, and Karolinska Institutet–NIH Doctoral Partnership Program in Neuroscience. The investigators had no relevant disclosures.