Dietary glycemic index is inversely associated with the risk of Parkinson's disease: A case–control study in Japan

• Published in: Nutrition (Burbank, Los Angeles County, Calif.) Vol. 26; no. 5; pp. 515 - 521
• Main Authors: Murakami, Kentaro, M.Sc, Miyake, Yoshihiro, M.D., Ph.D, Sasaki, Satoshi, M.D., Ph.D, Tanaka, Keiko, D.D.S., Ph.D, Fukushima, Wakaba, M.D., Ph.D, Kiyohara, Chikako, Ph.D, Tsuboi, Yoshio, M.D., Ph.D, Yamada, Tatsuo, M.D., Ph.D, Oeda, Tomoko, M.D., Ph.D, Miki, Takami, M.D., Ph.D, Kawamura, Nobutoshi, M.D, Sakae, Nobutaka, M.D., Ph.D, Fukuyama, Hidenao, M.D., Ph.D, Hirota, Yoshio, M.D., Ph.D, Nagai, Masaki, M.D., Ph.D
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.05.2010; [New York]: Elsevier Science Inc; Elsevier; Elsevier Limited
• Subjects: Aged; Biological and medical sciences; Bone surgery; Brain research; Carbohydrates; Case studies; Case-Control Studies; Case–control study; Confidence intervals; Diet; Diet Records; Dietary Carbohydrates - administration & dosage; Dietary Fiber; Dietary supplements; dietary surveys; Dopamine; Feeding. Feeding behavior; Female; Food; Fundamental and applied biological sciences. Psychology; Gastroenterology and Hepatology; Glycemic Index; Glycemic load; Hospitals; Humans; Hypotheses; Japan; Male; Medicine; Methods; Middle Aged; Odds Ratio; Orthopedics; Otolaryngology; Parkinson disease; Parkinson Disease - epidemiology; Parkinson's disease; patients; Questionnaires; Recruitment; risk assessment; Risk Factors; Sensitivity analysis; Surgery; Surveys and Questionnaires; University graduates; Variables; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Japan; Asia; Glycemic index; Parkinson's disease; Case–control study; Japan; Glycemic load; Nervous system diseases; Parkinson disease; Case-control study; Case control study; Cerebral disorder; Vertebrata; Mammalia; Central nervous system disease; Risk factor; Degenerative disease; Extrapyramidal syndrome
• ISSN: 0899-9007; 1873-1244
• DOI: 10.1016/j.nut.2009.05.021

Abstract Objective High glycemic index (GI) or glycemic load (GL) carbohydrates might be expected to decrease the risk of Parkinson's disease (PD) by an insulin-induced increase in brain dopamine. We conducted a hospital-based case–control study in Japan to examine associations between dietary GI and GL and other dietary carbohydrate variables, including intake of available carbohydrate and dietary fiber, and PD. Methods Patients with PD diagnosed using the U.K. Parkinson's Disease Society Brain Bank criteria ( n = 249) and controls without neurodegenerative diseases ( n = 368) were recruited. Dietary intake during the preceding month was assessed at the time of study recruitment using a validated, self-administered, semiquantitative, comprehensive diet history questionnaire. Results After adjustment for potential dietary and non-dietary confounding factors, dietary GI was significantly inversely associated with the risk of PD. Multivariate odds ratios (95% confidence intervals) for PD in the first, second, third, and fourth quartiles of dietary GI were 1.00 (reference), 1.03 (0.64–1.66), 0.68 (0.41–1.15), and 0.61 (0.34–1.09), respectively ( P for trend = 0.04). Conversely, no significant association was observed for other dietary carbohydrates, including dietary GL ( P for trend = 0.77), available carbohydrate intake ( P for trend = 0.28), or dietary fiber intake ( P for trend = 0.73). Conclusion This preliminary case–control study based on current dietary habits found an independent inverse relation between dietary GI and PD. Considering the plausibility of the putative mechanism, further investigation using a case–control design with accurate assessment of past dietary habits or a prospective design is warranted.