Angiotensin-converting enzyme insertion/deletion polymorphism is associated with cerebral white matter changes in Alzheimer's disease.
OBJECTIVE
The presence of cerebral white matter changes (WMC) has been reported as an important predictor of the rapidity of cognitive decline in Alzheimer's disease (AD). The association between the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and WMC in AD is yet to be elucidated. The present study aimed to examine the association between the ACE I/D polymorphism and WMC among AD patients in Taiwan.


METHODS
A total of 403 patients clinically diagnosed with AD were recruited in a cross-sectional study carried out in an area hospital in Kaohsiung, Taiwan. The ACE I/D polymorphism was genotyped, and cerebral white matter rating was carried out using the visual rating scale for age-related white matter changes.


RESULTS
The I allele was associated with a significantly lower total age-related white matter changes scale score compared with the D allele (4.83 vs 5.93, P = 0.013). The total age-related white matter changes scale score was significantly lower for the I/I genotype than for the I/D (4.37 vs 5.87, P = 0.009) and I/D + D/D genotypes (4.37 vs 5.91, P = 0.006), with no differences observed between the I/I + I/D and the D/D genotypes (5.08 vs 6.09, P = 0.373), after adjustment for age and hypertension. A stratified analysis by sex demonstrated that the I/I genotype was associated with significant lower WMC than other genotypes in women, but not in men.


CONCLUSIONS
The present study supports the hypothesis that the ACE I/D polymorphism is associated with the severity of WMC in patients with AD. Patients with AD who are homozygous for the I allele might be less likely to develop WMC, especially women. Geriatr Gerontol Int 2017; 17: 945-950.
Department of Neurology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.|Department of Neurology, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan.
Ping-Song
PS
Chou
Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung, Taiwan.
Shyh-Jong
SJ
Wu
Department of Neurology, National Taiwan University Hospital Yun-Lin Branch, Yun-Lin, Taiwan.
Yi-Hui
YH
Kao
Department of Neurology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.|Department of Neurology, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan.
Mei-Chuan
MC
Chou
Department of Family Medicine, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan.|Department of Family Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
Shu-Yu
SY
Tai
Department of Neurology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.|Department of Neurology, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan.|Department of and Master's Program in Neurology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
Yuan-Han
YH
Yang
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging / Q000235:genetics* / Q000473:pathology; D044466:Asian People / Q000235:genetics*; D003430:Cross-Sectional Studies; D005260:Female; D005838:Genotype; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D012720:Severity of Illness Index; D012737:Sex Factors; D013624:Taiwan; D014057:Tomography, X-Ray Computed; D066127:White Matter / Q000000981:diagnostic imaging / Q000473:pathology*
D007703:Peptidyl-Dipeptidase A
Alzheimer's disease; angiotensin-converting enzyme; genetic polymorphisms; insertion/deletion mutation; leukoaraiosis