Table 2.
The Change in Cognitive Scores Associated With Pulmonary Function
| Pulmonary Function | Each SD Increment† | ||||||
|---|---|---|---|---|---|---|---|
| Quintile 1 | Quintile 2 | Quintile 3 | Quintile 4 | Quintile 5 | p Trend* | ||
| Global cognitive score | |||||||
| Participants | 970 | 945 | 1053 | 1137 | 1180 | ||
| β (95% CI), Model 1‡ | 0 | 0.05 (−0.30, 0.40) | −0.18 (−0.53, 0.17) | −0.19 (−0.53, 0.15) | 0.23 (−0.11, 0.58) | .51 | 0.76 (0.65, 0.87) |
| β (95% CI), Model 2§ | 0 | 0.06 (−0.27, 0.39) | −0.18 (−0.51, 0.15) | −0.07 (−0.40, 0.25) | 0.19 (−0.13, 0.51) | .47 | 0.53 (0.44, 0.62) |
| β (95% CI), Model 3|| | 0 | 0.07 (−0.26, 0.41) | −0.16 (−0.49, 0.17) | −0.09 (−0.42, 0.23) | 0.12 (−0.20, 0.45) | .99 | 0.44 (0.34, 0.53) |
| Immediate memory | |||||||
| Participants | 1310 | 1276 | 1337 | 1405 | 1445 | ||
| β (95% CI), Model 1 | 0 | 0.08 (−0.03, 0.19) | 0.05 (−0.06, 0.16) | 0.11 (0.00, 0.21) | 0.32 (0.21, 0.43) | <.0001 | 0.19 (0.16, 0.22) |
| β (95% CI), Model 2 | 0 | 0.06 (−0.04, 0.17) | 0.03 (−0.08, 0.13) | 0.08 (−0.02, 0.18) | 0.24 (0.14, 0.34) | <.0001 | 0.14 (0.11, 0.17) |
| β (95% CI), Model 3 | 0 | 0.06 (−0.05, 0.16) | 0.01 (−0.10, 0.11) | 0.05 (−0.05, 0.16) | 0.19 (0.09, 0.30) | .0012 | 0.12 (0.09, 0.15) |
| Delayed memory | |||||||
| Participants | 997 | 971 | 1076 | 1159 | 1202 | ||
| β (95% CI), Model 1 | 0 | 0.11 (−0.02, 0.23) | 0.01 (−0.12, 0.13) | 0.05 (−0.07, 0.17) | 0.23 (0.10, 0.35) | .0042 | 0.18 (0.14, 0.22) |
| β (95% CI), Model 2 | 0 | 0.09 (−0.03, 0.21) | 0.00 (−0.12, 0.12) | 0.05 (−0.07, 0.17) | 0.18 (0.06, 0.29) | .0291 | 0.13 (0.10, 0.17) |
| β (95% CI), Model 3 | 0 | 0.10 (−0.03, 0.22) | 0.00 (−0.12, 0.12) | 0.03 (−0.09, 0.15) | 0.16 (0.04, 0.28) | .0718 | 0.12 (0.08, 0.16) |
| Subtraction calculation | |||||||
| Participants | 1630 | 1627 | 1637 | 1650 | 1645 | ||
| β (95% CI), Model 1 | 0 | −0.13 (−0.24, −0.01) | −0.10 (−0.21, 0.02) | −0.08 (−0.20, 0.04) | 0.04 (−0.08, 0.16) | .33 | 0.19 (0.16, 0.23) |
| β (95% CI), Model 2 | 0 | −0.13 (−0.25, −0.02) | −0.12 (−0.24, −0.01) | −0.10 (−0.21, 0.02) | −0.05 (−0.16, 0.07) | .67 | 0.13 (0.10, 0.17) |
| β (95% CI), Model 3 | 0 | −0.13 (−0.25, −0.02) | −0.12 (−0.23, −0.00) | −0.11 (−0.22, 0.01) | −0.08 (−0.19, 0.04) | .30 | 0.10 (0.07, 0.14) |
| Date orientation | |||||||
| Participants | 1655 | 1645 | 1650 | 1657 | 1657 | ||
| β (95% CI), Model 1 | 0 | 0.13 (0.04, 0.21) | 0.16 (0.08, 0.25) | 0.09 (−0.00, 0.17) | 0.15 (0.06, 0.24) | .0100 | 0.16 (0.13, 0.18) |
| β (95% CI), Model 2 | 0 | 0.13 (0.04, 0.21) | 0.15 (0.06, 0.23) | 0.09 (0.01, 0.18) | 0.11 (0.02, 0.19) | .0724 | 0.11 (0.09, 0.13) |
| β (95% CI), Model 3 | 0 | 0.13 (0.04, 0.21) | 0.14 (0.06, 0.23) | 0.07 (−0.01, 0.16) | 0.07 (−0.02, 0.15) | .49 | 0.08 (0.06, 0.11) |
Notes: BMI = body mass index; CI = confidence interval; SD = standard deviation.
*General linear regression models were used to obtain coefficients (β [95% CI]) for the change in cognitive scores for quintiles 2–5 versus the quintile 1 of pulmonary function. Changes in cognitive scores were computed as the scores at baseline subtracting from those at follow-up.
†Repeated-measures generalized estimating equations were used to test cognitive change associated with each SD increment of pulmonary function over time.
‡Model 1 was adjusted for age and gender.
§Model 2 was adjusted for Model 1 plus education, region, smoking, alcohol intake, physical activity, physical function, and global cognitive score at baseline.
||Model 3 was adjusted for Model 2 plus height, BMI, lung disease, hypertension, dyslipidemia, diabetes, heart disease, stroke, and psychiatric disorders at baseline.