Lifestyle Factors and Risk of Amyotrophic Lateral Sclerosis: A Case-Control Study in Japan

Okamoto, Kazushi; Kihira, Tameko; Kondo, Tomoyoshi; Kobashi, Gen; Washio, Masakazu; Sasaki, Satoshi; Yokoyama, Tetsuji; Miyake, Yoshihiro; Sakamoto, Naomasa; Inaba, Yutaka; Nagai, Masaki

doi:10.1016/j.annepidem.2009.01.015

« Previous Next »Annals of Epidemiology
Volume 19, Issue 6 , Pages 359-364, June 2009

Lifestyle Factors and Risk of Amyotrophic Lateral Sclerosis: A Case-Control Study in Japan

Kazushi Okamoto, MD
- Department of Public Health, Aichi Prefectural College of Nursing and Health
- Address correspondence and reprint requests to: Kazushi Okamoto, MD, Aichi Prefectural College of Nursing and Health, Togoku, Kamishidami, Moriyama-ku, Nagoya 463-8502, Japan. Tel: +81-52-736-1401; Fax: +81-52-736-1415.
Tameko Kihira, MD
- Department of Neurology, Wakayama Medical University
Tomoyoshi Kondo, MD
- Department of Neurology, Wakayama Medical University
Gen Kobashi, MD
- Molecular Biostatistics Research Team, Research Center for Charged Particle Therapy, National Institute of Radiological Science
Masakazu Washio, MD
- Department of Public Health, St. Mary's College
Satoshi Sasaki, MD
- Department of Epidemiology, Tokyo University
Tetsuji Yokoyama, MD
- Department of Technology Assessment and Biostatistics, National Institute of Public Health
Yoshihiro Miyake, MD
- Department of Public Health, Fukuoka University School of Medicine
Naomasa Sakamoto, MD
- Department of Hygiene, Hyogo College of Medicine
Yutaka Inaba, MD
- Department of Epidemiology, Juntendo University School of Medicine
Masaki Nagai, MD
- Department of Public Health, Saitama Medical School

Received 19 March 2008; accepted 15 January 2009. published online 03 April 2009.

Purpose

We examined the associations between lifestyle factors and the risk of amyotrophic lateral sclerosis (ALS) using a case-control study in Aichi Prefecture, Japan.

Methods

The study comprised 183 ALS patients diagnosed by the El Escorial World Federation of Neurology criteria as well as 366 gender- and age-matched controls randomly selected from the general population with the use of the basic register of residents. Detailed information on lifestyle factors was obtained through a mailed self-administered questionnaire. The strength of association between ALS and a potential risk factor was assessed by calculating odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Vigorous physical activity, self reported stress, a type A behavior pattern, and less frequent intakes of green-yellow vegetables were significantly associated with increased risk of ALS, whereas smoking and drinking habits were not. The greatest effect on risk for ALS was posed by the combination of a type A behavior pattern and less frequent intakes of green-yellow vegetables (adjusted OR, 11.2; 95% CI, 3.8 to 33.0).

Conclusion

These data suggested that imbalances between excessive productions of oxidants as patient-specific factors and a diminished or missing antioxidant defense system in motor neurons may increase the risk of ALS.

Key Words: Amyotrophic Lateral Sclerosis, Epidemiology, Case-Control Study Personality, Oxidants, Antioxidants

Selected Abbreviations and Acronyms: ALS, amyotrophic lateral sclerosis, MET, metabolic rate, OR, odds ratio, CI, confidence interval