Physical function is weakly associated with angiotensin-converting enzyme gene I/D polymorphism in elderly Japanese subjects.
BACKGROUND
The turning point in the deterioration of physical function seems to occur between the ages of 70 and 80 years. In particular, muscle strength may decline even more in subjects older than 75. A recent study found that the angiotensin-converting enzyme (ACE) genotype also affects physiological left ventricular hypertrophy. A very limited number of papers have examined genetic differences in resistance and endurance forms of a single sporting discipline.


OBJECTIVE
The purpose of this study was to evaluate the relationship between ACE genotype and physical function by controlling the known confounding factors including dental status.


METHODS
We selected 431 subjects who were aged 76 years and did not require special care for their daily activities. We conducted a medical examination, followed by 5 physical function tests, as follows: (1) maximum hand grip strength, (2) maximal isometric knee extensor strength, (3) maximal stepping rate for 10 s, (4) one-leg standing time with eyes open and (5) 10-meter maximum walking speed. Subjects were genotyped for the ACE intron 16 Alu insertion. In addition, serum concentrations of total cholesterol, total protein, IgA and IgG were measured at a commercial laboratory. The Eichner index was used as an indicator of occlusal condition. Multiple linear regression analysis was performed to evaluate the relationship between the ACE gene insertion/deletion (I/D) polymorphism and physical function considering confounding factors.


RESULTS
The ACE gene I/D polymorphism was positively associated with hand grip strength and 10-meter maximum walking speed. Betas of hand grip strength were 0.09 for I/D (p = 0.022) and 0.12 for insertion/insertion (I/I; p = 0.004). Betas of 10-meter walking speed were -0.11 for I/D (p = 0.093) and -0.14 for I/I (p = 0.039). Dental status such as Eichner index class C was significantly associated with one-leg standing time with eyes open (beta -0.11; p = 0.028).


CONCLUSIONS
This study suggests that there is a significant relationship between ACE genotype and physical function. In particular, subjects with the ACE deletion/deletion genotype were associated with upper extremities.
Yoshihara
A
A
Division of Preventive Dentistry, Department of Oral Health Science, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan. akihiro@dent.niigata-u.ac.jp
Tobina
T
T
Yamaga
T
T
Ayabe
M
M
Yoshitake
Y
Y
Kimura
Y
Y
Shimada
M
M
Nishimuta
M
M
Nakagawa
N
N
Ohashi
M
M
Hanada
N
N
Tanaka
H
H
Kiyonaga
A
A
Miyazaki
H
H
D000368:Aged; D000375:Aging / Q000235:genetics* / Q000502:physiology*; D020087:Alu Elements; D044466:Asian People / Q000235:genetics; D005260:Female; D005838:Genotype; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D054643:INDEL Mutation; D007438:Introns; D007564:Japan; D008297:Male; D053580:Muscle Strength / Q000502:physiology; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D010809:Physical Fitness / Q000502:physiology*; D011110:Polymorphism, Genetic; D016138:Walking / Q000502:physiology
D007703:Peptidyl-Dipeptidase A