TABLE 3. Associations of Self-reported Use of Spoken and Written Japanese and English with Dementia Outcomes.
| Probable or possible | ||||||
|---|---|---|---|---|---|---|
| All-cause dementia | Alzheimer disease | Probable Vascular dementia | ||||
| Language use group (number evaluated for dementia) | Cases/total no. or cases/person years | Adjusteda OR or HR (95% CI) | Cases/total no. or cases/person years | Adjusteda OR or HR (95% CI) | Cases/total no. or cases/person years | Adjusteda OR or HR (95% CI) |
| Analysis 1: Prevalent outcomes at Examination 4 (cases/total; odds ratio) | ||||||
| Neither spoke nor read Japanese (n = 29) | 18/561 | 0.78 (0.45-1.35) | 5/561 | 0.48 (0.17-1.33) | 6/561 | 0.96 (0.38-2.40) |
| Spoke but did not read Japaneseb (n = 168) | 91/1,847 | 1.0 | 48/1,847 | 1.0 | 23/1,847 | 1.0 |
| Both spoke and read Japanese (n = 91) | 45/731 | 1.80 (0.74-4.39) | 21/731 | 2.07 (0.53-8.13) | 14/731 | 1.22 (0.58-2.56) |
| Analysis 2: Incident outcomes at Examinations 5-7 (cases/ person years; hazard ratio) | ||||||
| Neither spoke nor read Japanese (n = 116) | 29/2,631 | 0.68 (0.46-1.02) | 20/2,631 | 0.79 (0.48-1.29) | 4/2,631 | 0.47 (0.17-1.35) |
| Spoke but did not read Japaneseb (n = 460) | 144/8,232 | 1.0 | 86/8,232 | 1.0 | 28/8,232 | 1.0 |
| Both spoke and read Japanese (n = 194) | 63/2,975 | 1.03 (0.76-1.40) | 32/2,975 | 0.84 (0.56-1.28) | 13/2,975 | 1.22 (0.62-2.40) |
| Analysis 3: Incident outcomes at Examinations 6-7 (cases/ person years; hazard ratio). | ||||||
| Analysis 3a: Japanese. | ||||||
| Neither spoke nor read Japanese (n = 83) | 32/2,180 | 0.88 (0.58-1.32)‡ | 18/2,180 | 0.74(0.43-1.26)‡ | 8/2,180 | 1.66 (0.65-4.23)‡ |
| Spoke but did not read Japaneseb (n = 188)c | 81/4,440 | 1.0 | 55/4,440 | 1.0 | 10/4,440 | 1.0 |
| Both spoke and read Japanese (n = 28)c | 12/558 | 1.01 (0.54-1.89) | 7/558 | 0.86 (0.38-1.93) | 2/558 | 1.47 (0.31-6.99) |
| Analysis 3b: English. | ||||||
| Not highly literate in English (n = 47) | 14/484 | 1.49 (0.82-2.70) | 10/484 | 1.63 (0.80-3.33) | 3/484 | 2.10 (0.56-7.90) |
| Highly literate in Englishb (n = 252) | 111/6,694 | 1.0 | 70/6,694 | 1.0 | 17/6,694 | 1.0 |
| Analysis 3c: both Japanese and English | ||||||
| Highly literate in neither Japanese nor English (n = 35) | 11/373 | 1.62 (0.83-3.12) | 8/373 | 1.81 (0.83-3.97) | 3/373 | n/a |
| Highly literate in English but not Japaneseb (n = 236) | 102/6,247 | 1.0 | 65/6,247 | 1.0 | 15/6,4247 | n/a |
| Highly literate in Japanese but not English (n = 12) | 3/112 | 1.17 (0.36-3.80) | 2/112 | 1.16 (0.27-4.91) | 0/112 | n/a |
| Highly literate in both Japanese and English (n = 16) | 9/447 | 1.08 (0.54-2.18) | 5/447 | 0.95 (0.38-2.41) | 2/447 | n/a |
a
Adjusted for age and education only unless indicated
b
Reference category
c
Models also adjusted for height
“n/a” indicates too few cases of incident vascular dementia were available for these analyses