Social class inequalities in self-rated health and their gender and age group differences in Japan.
BACKGROUND
Few studies have examined social inequalities in self-rated health in Japan, and the issue of gender differences related to social inequalities in self-rated health remains inconclusive.


METHODS
The data derived from interviews with 2987 randomly selected Japanese adults in four prefectures in Japan who completed the cross-national World Mental Health survey from 2002 through 2005. We calculated odds ratios (ORs) of having poor self-rated physical and mental health by two social class indicators independently with multivariate logistic regression models, adjusted for age, gender, marital status, and area. Stratified analyses by gender and age group were also conducted.


RESULTS
The adjusted ORs of the lowest educational attainment category having poor self-rated physical and mental health were 1.42 (95% confidence interval [CI]: 1.15-1.76) and 1.37 (95% CI: 1.10-1.70), respectively. Among females, educational attainment had significant linear associations with self-rated physical and mental health. Adjusted household income was also significantly associated with self-rated physical health among female respondents. No associations were found among males. While educational attainment was associated with self-rated health among the young age group, adjusted household income was associated with self-rated physical health in the middle and old age group.


CONCLUSIONS
These results indicated social inequalities in self-rated health and prominent social inequalities in self-rated health among females in Japan. Social inequalities in self-rated health seemed to exist across age groups. However, the mechanism of social inequalities in self-rated health could be different depending on the age group.
Honjo
Kaori
K
Social and Environmental Medicine, Osaka University Graduate School of Medicine, Suita, Osaka. khonjyo@pbhel.med.osaka-u.ac.jp
Kawakami
Norito
N
Takeshima
Tadashi
T
Tachimori
Hisateru
H
Ono
Yutaka
Y
Uda
Hidenori
H
Hata
Yukihiro
Y
Nakane
Yoshibumi
Y
Nakane
Hideyuki
H
Iwata
Noboru
N
Furukawa
Toshiaki A
TA
Watanabe
Makoto
M
Nakamura
Yosikazu
Y
Kikkawa
Takehiko
T
D000328:Adult; D000367:Age Factors; D005260:Female; D006304:Health Status; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D012923:Social Class