Table 4- Overview of studies on amyotrophic lateral sclerosis risk factors in sub-Sahara Africa
Author, year of
publication
Wall [152],1972
Country/Setting
Design/year
Population characteristics
Diagnostic criteria/ Prevalence
tools
Clinical (no ENMG) NA
Risk factors
Comments
Zimbabwe
Hospital-based
Retrospective
1967-1971
13 (men 10) consecutive
patients; age 24-55 y.
NA
6 participants had sensory changes
Osuntokun [74],
1974
Nigeria
Hospital-based
Retrospective
1958 -1973
92 patients with MND
ALS 73; PMA 10, SMA 9
ENMG/Muscle
biopsy/
0.21/1000
NA
Mean age at onset: 39y
Mean duration of disease exceeded 15y in
8% of participants
4 patients with ALS had poliomyelitis in
childhood.
Osuntokun [69] ,
1987
Nigeria
Community-based
Cross-sectional
1985
18954 participants (men
Screening
9282); 58% <20 y and 11%>50 questionnaire
y
developed by the
authors
South Africa Hospital- Retrospective Cases 59 blacks (mean age 47.4 y.); Clinical and ENMG
based
collected during 9.5 y. 16 whites and 2 coloured
in
(mean age 54 y.)
9
45%
Indians (mean age 54y)
MND: 15/100,000
NA
Blacks/white &
coloured/Indians (per
100,000) 0.88/2·7/1.4
NA
Nigeria
Hospital-based
Retrospective
2003-2007
8440 admissions; 1249 (men
640) with neurological
diseases, mean age 45 y.;
10 (men 4) with ALS
0.8%
NA
Abdulla [75], 1997 Sudan
Hospital-based
Retrospective:
1993-1995
28 (men 17) patients with
Clinical and ENMG NA
MND; 19 (men 14) with ALS
Kengne [39], 2006
Cameroon
Hospital-based
Retrospective
1993-2001
4041 neurologic consultations; Not provided
145 with neurodegenerative
diseases
10 (men 8) with ALS; mean
age 50.9 y.
Imam [153], 2004
Nigeria
Hospital-based
Retrospective
1980-99
16 (men 15) participants; age
16-60y.
El Escorial
NA
diagnostic criteria
for ALS, no ENMG
NA
Adam [77], 1992
Kenya
Hospital-based
Retrospective
1978-88
47(men 35) participants with
MND;
Age 13-80y
18 had ALS
Clinical (ENMG in NA
1/3 of participants)
NA
Cosnett [73], 1989
Ekenze [40], 2010
Not specified
Mean age of onset: 47y (blacks) and 54y (in
whites and indians)
29% of participants not followed up.
Family history of MND Mean age of onset: 40y
in 14%
12% of all
neurodegeneration
2.5/1000 of all
neurologic consultation
4 selected degenerative brain diseases:
Dementia, PD, ALS and chorea
Duration of disease: 5m to 4y.
1
Tekle-Haimanot
[70], 1990
Ethiopia
Community-based
Cross-sectional
1986-88
60820 participants (men
29412), 59% aged < 20 y
3 (2 men) had MND
Screening
questionnaire and
neurological exam
Harries [154], 1955 Ethiopia
Hospital-based
Case series
1954
2(all males) participants
Age 26 and 30y
Clinical (no ENMG) NA
Jacquin-cotton [71], Senegal
1970
Hospital-based
Retrospective
1960-1969
Clinical (No
ENMG)
Piquemal [72]
1982
Ivory coast
Hospital-based
Retrospective
1971-80
Collomb [155], 1968 Senegal
Hospital-based
Retrospective
1960-68
6100 participants with
neurological disorders
18 (16 men) participants with
ALS, age 25-70y
4000 participants with
neurological disorders
30 (men 22) participants had
ALS, 50% aged <40y
18 (17men)participants with
ALS, age 25-70y
Sene [76], 2004
Retrospective
1999-2000
33 (19 men) participants with
ALS;
El Escorial
(ENMG in half of
the patients)
Senegal Hospital
5/100,000
NA
A population survey of neurological
diseases
NA
2.9/1000
A study of patients with paraplegia in a
neurological unit
Clinical (no ENMG) 7.5/1000
NA
Duration of disease: 3m to 5 y.
Clinical (no ENMG) NA
NA
Duration of diseae: 4m to 13y
Definite ALS: 57%,
Probable: 30%, Possible ALS: 9%
Suspect ALS: 3%
age at onset 14-67 y.
Duration of disease: 6m to 5y.
ALS: amyotrophic lateral sclerosis; ENMG: Electroneuromyography; MND: Motor Neuron Disease; NA: Not available; PMA: Progressive muscular atrophy; SMA: Spinal
Muscular Atrophy; y:years; m: months
2