Characteristics of the study populations
| Characteristic | Participants from CSHA,* mean ± SD | Participants from NACC,* mean ± SD | ||
|---|---|---|---|---|
| Healthy controls group n = 6411 | Dementia group n = 1158* | Healthy controls group n = 6000 | Dementia group n = 501 | |
| Age at start of study, yr | 76.04 ± 6.90 | 80.79 ± 6.67 | 72.93 ± 7.76 | 79.87 ± 7.07 |
| Education, yr | 10.49 ± 3.78 | 9.35 ± 3.88 | 15.71 ± 3.00 | 15.00 ± 3.25 |
| MMSE score at start of study | 27.07 ± 2.69 | 23.71 ± 5.14 | 28.98 ± 1.34 | 28.24 ± 1.77 |
| MMSE decline at end of study | −0.54 ± 2.64† | −6.70 ± 5.94‡ | −0.08 ± 1.45§ | −5.36 ± 5.33¶ |
Note: CSHA = Canadian Study of Health and Aging,22 MMSE = Mini-Mental State Examination, NACC = National Alzheimer’s Coordinating Center’s Uniform Data Set,25 SD = standard deviation.
↵* Dementia developed in 1158 participants over the course of the study, including 361 prevalent cases of dementia.
↵† Participants who had normal cognitive function through the course of the study and had at least 1 follow-up MMSE (n = 3951).
↵‡ Participants who had a diagnosis of dementia during the course of the study and had at least 1 follow-up MMSE (n = 695).
↵§ Participants who had normal cognitive function through the course of the study and had at least 1 follow-up MMSE (n = 5864).
↵¶ Participants who had a diagnosis of dementia during the course of the study and had at least 1 follow-up MMSE (n = 486).