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. 2014 Apr 17;144(6):890–901. doi: 10.3945/jn.113.189027

TABLE 2.

Analysis of baseline caffeine intake (continuous, 100 mg/d), alcohol intake (g/d), and the NAS, and longitudinal change in cognitive performance (total and sex-stratified), time-interval mixed-effects linear regression analysis, BLSA, 1962–20081

Total: model 1
 Men: model 2
 Women: model 3
γ ± SEE2 P3 γ ± SEE2 P3 γ ± SEE2 P3
MMSE, total score4 n = 555 n′ = 1102 n = 328 n′ = 595 n = 227 n′ = 507
 Fixed effects
  Intercept (γ00 for π0i) +29.48 ± 0.27 <0.001 +29.76 ± 0.39 <0.001 +29.22 ± 0.36 <0.001
  Time (γ10 for π1i) +0.135 ± 0.106 0.201 +0.086 ± 0.148 0.559 +0.191 ± 0.182 0.294
  Agebase −0.052 ± 0.009 <0.001 −0.067 ± 0.013 <0.001 −0.032 ± 0.011 0.004
  Agebase × time −0.009 ± 0.004 0.014 −0.005 ± 0.006 0.386 −0.011 ± 0.006 0.044
  Gender (women vs. men) +0.182 ± 0.159 0.253 — — — —
  Gender × time +0.020 ± 0.059 0.733 — — — —
  Caffeine (γ01 for π0i) +0.094 ± 0.047 0.043 +0.001 ± 0.001 0.099 +0.060 ± 0.072 0.407
  Caffeine × time (γ11 for π1i) −0.004 ± 0.016 0.795 −0.000 ± 0.000 0.322 +0.008 ± 0.032 0.813
  NAS (γ02 for π0i) +0.072 ± 0.025 0.004 +0.058 ± 0.034 0.094 +0.104 ± 0.036 0.003
  NAS × time (γ12 for π1i) −0.004 ± 0.009 0.624 +0.003 ± 0.012 0.838 −0.013 ± 0.016 0.405
  Alcohol (γ03 for π0i) +0.006 ± 0.006 0.295 +0.008 ± 0.006 0.198* −0.008 ± 0.011 0.432
  Alcohol × time (γ13 for π1i) −0.003 ± 0.002 0.095 −0.001 ± 0.002 0.692* −0.008 ± 0.005 0.132
 Random effects
  Level 1 residuals (Rij) +0.79 ± 0.03 <0.001 +0.93 ± 0.05 <0.001 +0.622 ± 0.034 <0.001
  Level 2 residuals
   Intercept (ξ0i) +1.38 ± 0.05 <0.001 +1.36 ± 0.08 <0.001 +1.305 ± 0.034 <0.001
   Linear slope (ξ1i) +0.32 ± 0.02 <0.001 +0.30 ± 0.03 <0.001 +0.389 ± 0.037 <0.001
CVLT-List A, total score n = 568 n’ = 1111 n = 296 n’ = 559 n = 272 n’ = 552
 Intercept (γ00 for π0i) +58.32 ± 1.29 <0.001 +59.57 ± 1.85 <0.001 +63.18 ± 1.71 <0.001
 Time (γ10 for π1i) +0.060 ± 0.393 0.878 +0.191 ± 0.535 0.720 −0.175 ± 0.52 0.751
 Agebase −0.424 ± 0.036 <0.001 −0.472 ± 0.058 <0.001 −0.380 ± 0.046 <0.001
 Agebase × time −0.010 ± 0.010 0.317 −0.004 ± 0.015 0.789 −0.008 ± 0.014 0.554
 Gender (women vs. men) +6.547 ± 0.957 <0.001 — — — —
 Gender × time −0.269 ± 0.249 0.280 — — — —
 Caffeine (γ01 for π0i) +0.090 ± 0.276 0.745 −0.204 ± 0.348 0.559 +0.587 ± 0.480 0.222
 Caffeine × time (γ11 for π1i) +0.004 ± 0.064 0.944 −0.063 ± 0.078 0.419 +0.076 ± 0.109 0.484
 NAS (γ02 for π0i) +0.291 ± 0.152 0.055 +0.365 ± 0.231 0.114 +0.282 ± 0.203 0.164
 NAS × time (γ12 for π1i) +0.086 ± 0.040 0.031 +0.116 ± 0.056 0.040 +0.081 ± 0.059 0.169
 Alcohol (γ03 for π0i) +0.053 ± 0.031 0.088 +0.050 ± 0.038 0.191 +0.059 ± 0.057 0.295
 Alcohol × time (γ13 for π1i) −0.008 ± 0.007 0.208 −0.007 ± 0.007 0.298* +0.016 ± 0.017 0.351
CVLT-delayed recall, total score n = 568 n’ = 1111 n = 296 n’ = 559 n = 272 n’ = 552
 Intercept (γ00 for π0i) +12.52 ± 0.40 <0.001 +12.94 ± 0.58 <0.001 +13.47 ± 0.52 <0.001
 Time (γ10 for π1i) −0.021 ± 0.113 0.850 +0.008 ± 0.159 0.959 −0.072 ± 0.151 0.631
 Agebase −0.112 ± 0.011 <0.001 −0.139 ± 0.018 <0.001 −0.089 ± 0.014 <0.001
 Agebase × time −0.004 ± 0.003 0.157 −0.004 ± 0.004 0.376 −0.003 ± 0.004 0.502
 Gender (women vs. men) +1.281 ± 0.299 <0.001 — — — —
 Gender × time −0.024 ± 0.071 0.738 — — — —
 Caffeine (γ01 for π0i) +0.015 ± 0.086 0.858 +0.006 ± 0.110 0.953 −0.017 ± 0.146 0.909
 Caffeine × time (γ11 for π1i) −0.083 ± 0.018 0.964 −0.033 ± 0.023 0.148* +0.042 ± 0.030 0.157
 NAS (γ02 for π0i) +0.102 ± 0.047 0.030 +0.131 ± 0.073 0.071 +0.092 ± 0.062 0.140
 NAS × time (γ12 for π1i) +0.017 ± 0.011 0.131 +0.029 ± 0.017 0.081 +0.014 ± 0.016 0.373
 Alcohol (γ03 for π0i) +0.013 ± 0.010 0.174 +0.013 ± 0.012 0.550 +0.012 ± 0.017 0.477
 Alcohol × time (γ13 for π1i) −0.001 ± 0.002 0.498 −0.001 ± 0.002 0.550 +0.004 ± 0.005 0.366
BVRT, total errors n = 1005 n’ = 1975 n = 620 n’ = 1152 n = 385 n’ = 822
 Intercept (γ00 for π0i) +3.68 ± 0.31 <0.001 +4.03 ± 0.39 <0.001 +3.49 ± 0.43 <0.001
 Time (γ10 for π1i) +0.051 ± 0.048 0.288 +0.051 ± 0.058 0.384 −0.072 ± 0.082 0.377
 Agebase +0.112 ± 0.006 <0.001 +0.110 ± 0.008 <0.001 +0.111 ± 0.010 <0.001
 Agebase × time +0.005 ± 0.001 <0.001 +0.004 ± 0.001 <0.001 +0.005 ± 0.002 0.004
 Gender (women vs. men) −0.005 ± 0.244 0.985 — — — —
 Gender × time −0.054 ± 0.035 0.128 — — — —
 Caffeine (γ01 for π0i) −0.157 ± 0.070 0.024 −0.181 ± 0.092 0.050 −0.164 ± 0.112 0.144
 Caffeine × time (γ11 for π1i) +0.012 ± 0.005 0.031 +0.008 ± 0.012 0.507 +0.011 ± 0.007 0.138
 NAS (γ02 for π0i) −0.065 ± 0.037 0.076 −0.052 ± 0.051 0.311 −0.090 ± 0.054 0.099
 NAS × time (γ12 for π1i) −0.001 ± 0.005 0.878 +0.002 ± 0.007 0.795 −0.002 ± 0.008 0.776
 Alcohol (γ03 for π0i) −0.007 ± 0.007 0.307 −0.001 ± 0.007 0.933 −0.020 ± 0.016 0.220
 Alcohol × time (γ13 for π1i) −0.000 ± 0.001 0.851 −0.000 ± 0.001 0.539 +0.001 ± 0.002 0.718
VFT-C, total score n = 602 n’ = 1236 n = 346 n’ = 655 n = 256 n’ = 581
 Intercept (γ00 for π0i) +18.29 ± 0.47 <0.001 +18.21 ± 0.65 <0.001 +20.07 ± 0.70 <0.001
 Time (γ10 for π1i) +0.167 ± 0.093 0.073 +0.128 ± 0.140 0.362 +0.314 ± 0.138 0.022
 Agebase −0.169 ± 0.015 <0.001 −0.173 ± 0.022 <0.001 −0.165 ± 0.023 <0.001
 Agebase × time −0.014 ± 0.003 <0.001 −0.012 ± 0.005 0.030 −0.017 ± 0.004 <0.001
 Gender (women vs. men) −0.341 ± 0.460 0.458 — — — —
 Gender × time −0.084 ± 0.139 0.545 — — — —
 Caffeine (γ01 for π0i) −0.036 ± 0.009 0.680 +0.002 ± 0.108 0.985 −0.001 ± 0.002 0.481
 Caffeine × time (γ11 for π1i) +0.006 ± 0.014 0.633 −0.003 ± 0.018 0.871 +0.000 ± 0.000 0.231
 NAS (γ02 for π0i) +0.051 ± 0.047 0.279 +0.052 ± 0.062 0.410 +0.056 ± 0.074 0.443
 NAS × time (γ12 for π1i) +0.003 ± 0.008 0.741 +0.001 ± 0.012 0.907 +0.004 ± 0.012 0.739
 Alcohol (γ03 for π0i) +0.012 ± 0.010 0.257 +0.006 ± 0.011 0.576 +0.025 ± 0.023 0.263
 Alcohol × time (γ13 for π1i) −0.000 ± 0.001 0.975 −0.000 ± 0.002 0.967 +0.003 ± 0.003 0.352
VFT-L, total score n = 601 n’ = 1233 n = 346 n′ = 645 n = 255 n’ = 577
 Intercept (γ00 for π0i) +15.13 ± 0.60 <0.001 +14.43 ± 0.87 <0.001 +16.25 ± 0.84 <0.001
 Time (γ10 for π1i) +0.239 ± 0.102 0.020 +0.273 ± 0.140 0.052 +0.190 ± 0.174 0.277
 Agebase −0.040 ± 0.019 0.041 −0.019 ± 0.029 0.515 −0.057 ± 0.027 0.036
 Agebase × time −0.012 ± 0.003 0.001 −0.013 ± 0.005 0.012 −0.012 ± 0.005 0.026
 Gender (women vs. men) +0.729 ± 0.387 0.059 — — — —
 Gender × time −0.001 ± 0.055 0.987 — — — —
 Caffeine (γ01 for π0i) +0.028 ± 0.113 0.980 +0.097 ± 0.145 0.502* −0.116 ± 0.187 0.533
 Caffeine × time (γ11 for π1i) −0.023 ± 0.015 0.121 −0.038 ± 0.018 0.039 −0.000 ± 0.000 0.994
 NAS (γ02 for π0i) −0.051 ± 0.060 0.393 +0.033 ± 0.084 0.687 −0.139 ± 0.088 0.113
 NAS × time (γ12 for π1i) +0.001 ± 0.009 0.891 +0.006 ± 0.012 0.586 +0.001 ± 0.015 0.941
 Alcohol (γ03 for π0i) +0.021 ± 0.013 0.107 +0.028 ± 0.015 0.066 −0.006 ± 0.027 0.827
 Alcohol × time (γ13 for π1i) −0.002 ± 0.002 0.141 −0.002 ± 0.002 0.294 −0.002 ± 0.004 0.652
DS-F, total score n = 541 n’ = 1067 n = 285 n’ = 544 n = 256 n’ = 523
 Intercept (γ00 for π0i) +9.50 ± 0.30 <0.001 +10.04 ± 0.43 <0.001 +8.74 ± 0.40 <0.001
 Time (γ10 for π1i) −0.002 ± 0.060 0.978 +0.015 ± 0.093 0.869 +0.013 ± 0.077 0.862
 Agebase −0.036 ± 0.008 <0.001 −0.053 ± 0.013 <0.001 −0.026 ± 0.010 0.011
 Agebase × time −0.002 ± 0.001 0.237 −0.002 ± 0.002 0.293 −0.001 ± 0.002 0.588
 Gender (women vs. men) −0.493 ± 0.215 0.022 — — — —
 Gender × time +0.012 ± 0.034 0.729 — — — —
 Caffeine (γ01 for π0i) −0.039 ± 0.061 0.519 −0.077 ± 0.076 0.312 +0.031 ± 0.106 0.773
 Caffeine × time (γ11 for π1i) −0.010 ± 0.009 0.286 −0.005 ± 0.013 0.706 −0.022 ± 0.014 0.111
 NAS (γ02 for π0i) −0.003 ± 0.035 0.934 −0.002 ± 0.053 0.975 −0.010 ± 0.047 0.835
 NAS × time (γ12 for π1i) +0.010 ± 0.006 0.085 +0.001 ± 0.009 0.988 +0.022 ± 0.008 0.005
 Alcohol (γ03 for π0i) +0.015 ± 0.007 0.036 +0.022 ± 0.009 0.012 +0.003 ± 0.013 0.788
 Alcohol × time (γ13 for π1i) +0.000 ± 0.001 0.850 −0.001 ± 0.001 0.406 +0.003 ± 0.002 0.156
DS-B, total score n = 545 n’ = 1066 n = 284 n’ = 540 n = 261 n’ = 526
 Intercept (γ00 for π0i) +8.90 ± 0.32 <0.001 +9.08 ± 0.48 <0.001 +8.57 ± 0.40 <0.001
 Time (γ10 for π1i) −0.367 ± 0.098 <0.001 −0.383 ± 0.143 0.008 −0.298 ± 0.132 0.024
 Agebase −0.036 ± 0.009 <0.001 −0.044 ± 0.015 0.003 −0.032 ± 0.011 0.002
 Agebase × time +0.006 ± 0.002 0.008 +0.008 ± 0.004 0.041 +0.006 ± 0.003 0.050
 Gender (women vs. men) −0.257 ± 0.224 0.251 — — — —
 Gender × time +0.103 ± 0.057 0.073 — — — —
 Caffeine (γ01 for π0i) −0.040 ± 0.064 0.533 −0.068 ± 0.084 0.418 −0.034 ± 0.111 0.759
 Caffeine × time (γ11 for π1i) −0.008 ± 0.015 0.576 −0.022 ± 0.020 0.263 +0.014 ± 0.024 0.558
 NAS (γ02 for π0i) −0.051 ± 0.036 0.160 −0.052 ± 0.058 0.373 −0.035 ± 0.047 0.462
 NAS × time (γ12 for π1i) +0.003 ± 0.010 0.742 −0.003 ± 0.015 0.849 +0.012 ± 0.013 0.378
 Alcohol (γ03 for π0i) +0.021 ± 0.007 0.004 +0.024 ± 0.009 0.013 +0.018 ± 0.013 0.171
 Alcohol × time (γ13 for π1i) −0.002 ± 0.002 0.106 −0.003 ± 0.002 0.078 +0.001 ± 0.004 0.788
1

Models were further adjusted for baseline year of intake, race/ethnicity, education (y), baseline smoking status, and baseline BMI. See Materials and Methods for more details on covariate coding and model specifications. Random effects are presented only for the MMSE, for simplicity. *P < 0.10 for interaction with gender to test effect modification by gender for each of the 3 predictors’ effects (i.e., caffeine intake, alcohol intake, and NAS) on cognitive performance at baseline and cognitive change over time. BLSA, Baltimore Longitudinal Study of Aging; BVRT, Benton Visual Retention Test; CVLT, California Verbal Learning Test; DS-B, digits span-backward; DS-F, digits span-forward; MMSE, Mini Mental State Examination; NAS, nutrient adequacy score; Trails A, Trail Making Test, part A; Trails B, Trail Making Test, part B; VFT-C, Verbal Fluency Test-Categorical; VFT-L, Verbal Fluency Test-Letter.

2

n = number of participants in the analysis.

3

n′ = total number of visits included in the analysis.

4

Cognitive scores were in the direction of higher score indicated better performance with the exception of the BVRT and Trails A and B.