O. Elwan et al., BRAIN AGING IN A SAMPLE OF NORMAL EGYPTIANS COGNITION, EDUCATION, ADDICTION AND SMOKING, Journal of the neurological sciences, 148(1), 1997, pp. 79-86
The impact of duration of education, cannabis addiction and smoking on
cognition and brain aging is studied in 211 normal Egyptian volunteer
s with mean age 46.4+/-3.6 years (range: 20-76 years). Subjects were c
lassified into two groups: Gr I(non-addicts) with 174 subjects, mean a
ge 49.9+/-3.8 years (range 20-76 years), smokers and non-smokers, educ
ated and non-educated and Gr II (cannabis addicts) with 37 subjects, m
ean age 43.6+/-2.6 years (range 20-72 years) all smokers, educated and
non-educated. Outcome measures included the Paced Auditory Serial Add
ition test (PASAT) for testing attention and the Trailmaking test A, a
nd B (TMa and TMb) for testing psychomotor performance. Age correlated
positively with score of Trailmaking test (TMb) in the non-addict gro
up and in the addict group (TMa and TMb). Years of education correlate
d negatively with scores of Trialmaking test (TMb) in the non-addict g
roup (Gr I) but not the addict group (Or II). However, in both groups
mean scores of the Trailmaking test (TMa) were significantly lower in
subjects with a primary level of education than those with higher leve
ls of education. No significant difference was detected between male s
mokers and nonsmokers of Gr I (non-addicts) regarding any of the neuro
psychological tests. Yet, smokers and the non-educated group had poore
r attention compared to non-smokers of the same group. Cannabis addict
s (Gr II) had significantly poorer attention than non-addict normal vo
lunteers (Or I). It is concluded that impairment of psychomotor perfor
mance is age related whether in normal non-addicts or in cannabis addi
cts. A decline in attention was detected in cannabis addicts and has b
een considered a feature of pathological aging. Education in early lif
e as well as the duration of education are neuroprotectors for brain a
ging more so in the non-addict than addict group. Though cigarette smo
king per se has no effect on cognitive abilities in normal aging, it b
ecomes evident that its association with lack of education impairs att
ention. (C) 1997 Elsevier Science B.V.