Yoon Jin Choi1, In Young Choi2, Wooyoung Jang3, Su-Min Jeong4, Sanghyun Park5, Kyungdo Han6, Yoontaek Lee7, Dong Ho Lee8, Dong Wook Shin9. 1. Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea. 2. Department of Family Medicine & International Healthcare Center, Samsung Medical Center, Seoul, Republic of Korea. 3. Department of Neurology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Republic of Korea. Electronic address: neveu@gnah.co.kr. 4. Department of Family Medicine, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul, Republic of Korea; TH Chan School of Public Health, Harvard University, MA, USA. 5. Department of Biostatistics, Catholic University of Korea, Seoul, Republic of Korea. 6. Department of Statistics and Actuarial Science, Soongsil University, Seoul, Republic of Korea. 7. Department of Surgery, Ewha Womans University Medical Center, Seoul, Republic of Korea. 8. Department of Internal Medicine, Seoul National University Bundang Hospital, College of Medicine, Seoul National University, Seongnam, Republic of Korea. 9. Department of Family Medicine & Supportive Care Center, Samsung Comprehensive Cancer Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea. Electronic address: dwshin.md@gmail.com.
Abstract
INTRODUCTION: Previous evidence has suggested roles for α-synuclein propagation and vitamin B12 (VitB12) deficiency in the pathogenesis of Parkinson's disease (PD). We investigated whether gastric cancer (GC) patients who underwent gastrectomy had a lower risk of PD and whether VitB12 supplementation modified the risk. METHODS: GC patients aged ≥50 years who underwent curative gastrectomy between 2007 and 2012 (n = 72,216) and matched comparison groups (n = 211,389) were identified from the Korean National Health Insurance database. The risks of PD were analyzed by Cox regression. RESULTS: Compared to their matched comparison groups, GC patients who underwent gastrectomy showed a decreased risk of PD (adjusted HR [aHR] 0.86; 95% confidence interval [CI] 0.75-0.98), but the significance disappeared after further adjustment with smoking and body mass index (BMI). To elaborate, subtotal gastrectomy (STG) was associated with decreased risk of PD (aHR 0.85; 95% CI 0.74-0.99) while total gastrectomy (TG) was not (aHR 0.89; 95% CI 0.66-1.19), although the risk reduction was not significant when further adjusted for smoking and BMI. Among the patients who underwent TG, their risk of PD was markedly lower when they had VitB12 supplementation after surgery (aHR 0.36; 95% CI 0.17-0.76), while the risk was higher when they did not have any (aHR 1.55; 95% CI 1.03-2.32). CONCLUSIONS: GC patients who underwent gastrectomy and received uninterrupted VitB12 supplementation had a decreased incidence of PD. This study provides indirect epidemiological evidence for the potential roles of gastrectomy and VitB12 in the pathogenesis of PD.
INTRODUCTION: Previous evidence has suggested roles for α-synuclein propagation and vitamin B12 (VitB12) deficiency in the pathogenesis of Parkinson's disease (PD). We investigated whether gastric cancer (GC) patients who underwent gastrectomy had a lower risk of PD and whether VitB12 supplementation modified the risk. METHODS: GC patients aged ≥50 years who underwent curative gastrectomy between 2007 and 2012 (n = 72,216) and matched comparison groups (n = 211,389) were identified from the Korean National Health Insurance database. The risks of PD were analyzed by Cox regression. RESULTS: Compared to their matched comparison groups, GC patients who underwent gastrectomy showed a decreased risk of PD (adjusted HR [aHR] 0.86; 95% confidence interval [CI] 0.75-0.98), but the significance disappeared after further adjustment with smoking and body mass index (BMI). To elaborate, subtotal gastrectomy (STG) was associated with decreased risk of PD (aHR 0.85; 95% CI 0.74-0.99) while total gastrectomy (TG) was not (aHR 0.89; 95% CI 0.66-1.19), although the risk reduction was not significant when further adjusted for smoking and BMI. Among the patients who underwent TG, their risk of PD was markedly lower when they had VitB12 supplementation after surgery (aHR 0.36; 95% CI 0.17-0.76), while the risk was higher when they did not have any (aHR 1.55; 95% CI 1.03-2.32). CONCLUSIONS: GC patients who underwent gastrectomy and received uninterrupted VitB12 supplementation had a decreased incidence of PD. This study provides indirect epidemiological evidence for the potential roles of gastrectomy and VitB12 in the pathogenesis of PD.