Results of Florida's Amyotrophic Lateral Sclerosis Surveillance Project, 2009–2011

Abstract

ObjectiveStudies to determine the incidence and prevalence of amyotrophic lateral sclerosis (ALS) in defined geographic areas in the USA are needed. The Florida Department of Health received funding from the federal Agency for Toxic Substances and Disease Registry to implement a state-wide ALS Surveillance Project. The objectives of the project were to describe the demographic characteristics of ALS cases and to calculate the incidence and prevalence of ALS in Florida.Setting/participantsAll neurologists were asked to submit case reports for persons with ALS diagnosed and/or under their care during 1 January 2009 through 31 December 2011. A medical record verification form and an electromyogram (EMG) report were requested for a sample of cases and reviewed by an independent consulting neurologist to confirm ALS diagnosis. Death data were used to aid with case report collection.Primary and secondary outcome measuresDemographics, relevant history and clinical characteristics, El Escorial classifications, time from symptom onset to diagnosis, crude annual incidence rates and 2009 period prevalence are presented.ResultsThe 1450 reported ALS cases were more likely to be older, male, white and non-Hispanic. Slightly more than 4% of cases were reported as also having dementia, and 4.8% were reported to have an immediate family member diagnosed with ALS. Incidence rates ranged from 1.7 to 1.9 per 100 000 person-years during the project period and the 2009 period prevalence was 4.0 per 100 000 persons.ConclusionsProject findings are generally consistent with findings of population-based studies in Europe, as well as geographically limited studies in the USA. Our findings add to the growing body of epidemiological literature about ALS in the USA. Future epidemiological studies in the USA should focus on identifying cases from minority groups and those that may have limited access to healthcare, and should consider conducting capture–recapture analysis to assess case ascertainment.

Variation in worldwide incidence of amyotrophic lateral sclerosis: a meta-analysis

“…For the three remaining areas (Swabia, Lancashire, Hawaii) this was not possible; in these latter cases, we did not have access to the number of ALS cases by age and sex groups 9 , 39 , 60 . Number of cases or incidence rates of ALS by sex and age groups were available (present in the article or in supplementary material or provided on request by authors) for 36 areas 6 , 8 , 11–14 , 35–38 , 40–51 , 54–58 , 61 , 63 , 63 , 66 , 100 , 108 , 112 . For the remaining six articles, a graphical reading of the figure of age-specific incidence was performed to obtain rates 4 , 33 , 35 , 52 , 53 , 59 .…”

Prevalence of Amyotrophic Lateral Sclerosis — United States, 2012–2013

“…Because ALS is predominantly a disease that affects whites, these states and metro areas were selected for their over-representation of minority populations of blacks, Asians, and Hispanics. Incidence rates ranged from 1.1 to 2.1 per 100,000 personyears in individual states and metro areas (39,41,(49)(50)(51) and the incidence rate was 1.5 person-years for all states and metro areas combined (52). Incidence rates by race and ethnicity were calculated for all states and metro areas combined and showed that the incidence rate in whites was higher than the incidence rates for blacks and Asians.…”

“…Third, the calculation of ALS incidence with Registry data is not possible at this time because the date of diagnosis is not captured through the large administrative database approach, and cases without a date of diagnosis comprise 68% of cases in the Registry. However, through a separate Registry project, incidence has been calculated and the findings published for ALS incidence in smaller defined geographic areas of the United States (39,41,(49)(50)(51)(52). Finally, the Registry has been officially active since October 2009 and is still being enhanced.…”

Comparative analysis of C9orf72 and sporadic disease in an ALS clinic population

“…Age at disease onset and age at disease diagnosis were similar and comparable to published reports from other ALS cohorts. 26,27 Interestingly, C9Pos patients were more likely to receive a diagnosis sooner after symptom onset than C9Neg patients. This difference may be explained by a high index of suspicion in patients with a known family history of ALS.…”