title: Incidence of amyotrophic lateral sclerosis among American Indians and Alaska natives.
abstract: OBJECTIVE
  More thorough evaluation of amyotrophic lateral sclerosis (ALS) and motor neuron disease in unique populations could provide clues to etiologies for these idiopathic conditions, and educational programs for American Indian and Alaska Native (AI/AN) people and health care professionals on reservations could improve awareness, understanding, diagnosis, and treatment. In the ongoing search for susceptibility genes, studying particular racial groups, such as AI/ANs,might facilitate the identification of new mutations.
  
  
  OBJECTIVE
  To provide better understanding of ALS and secondarily of motor neuron disease among AI/AN people by estimating the incidence and prevalence among AI/ANs served by the Indian Health Service health care system.
  
  
  METHODS
  Analysis of electronic records for AI/ANs with ALS and with motor neuron disease separately for the calendar years 2002-2009 using inpatient and outpatient visit data from the Indian Health Service, which provides health care to eligible AI/ANs nationwide.
  
  
  METHODS
  Cases were defined by at least 2 inpatient or outpatient visits with the diagnosis.
  
  
  METHODS
  Crude and age-adjusted incidence and prevalence rates were calculated.
  
  
  RESULTS
  Seventy-one AI/ANs were diagnosed with ALS, yielding an average annual crude incidence rate of 0.63 cases per 100 000 and an age-adjusted incidence of 0.92. The median age at onset was 56.0 years and was higher among women than men (62.0 vs 55.0 years; P=.06). Age-specific incidence increased to 70 to 74 years. The crude and age-adjusted point prevalence rates were 2.00 and 4.12, respectively. The crude and age-adjusted incidence rates for motor neuron disease were 1.08 and 1.50, respectively. The annual rates were unchanged across the study period.
  
  
  CONCLUSIONS
  The incidence of ALS among AI/ANs appears to be lower than that reported for white populations, a finding congruent with reports of other minority populations. Community-based studies are important to confirm these findings and to examine reasons for the low rate of ALS among AI/ANs.
authors: Northern Navajo Medical Center, Medical Staff Office, Hwy 491 N, Shiprock, NM 87420, USA. paul.gordon@ihs.gov
authors: Paul H
authors: PH
authors: Gordon
authors: Jason M
authors: JM
authors: Mehal
authors: Robert C
authors: RC
authors: Holman
authors: Lewis P
authors: LP
authors: Rowland
authors: Andrew S
authors: AS
authors: Rowland
authors: James E
authors: JE
authors: Cheek
mesh_terms: D000367:Age Factors; D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000453:epidemiology* / Q000208:ethnology*; D005260:Female; D006801:Humans; D015994:Incidence; D007198:Indians, North American / Q000208:ethnology*; D004930:Inuit / Q000208:ethnology*; D008297:Male; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000453:epidemiology / Q000208:ethnology; D015995:Prevalence; D012737:Sex Factors; D014481:United States / Q000453:epidemiology / Q000208:ethnology; D016549:United States Indian Health Service