TABLE 5.
Associations between regular coffee consumption and cognitive function tests in the UK Biobank stratified by CMSG1
| Cups/day | 0–1 | 1–2 | 3–4 | |||
|---|---|---|---|---|---|---|
| β (95% CI) | P | β (95% CI) | P | β (95% CI) | P | |
| Fluid Intelligence2 | ||||||
| 0 | Reference | Reference | Reference | |||
| <1 | 0.11 (0.02, 0.19) | 0.01 | 0.21 (0.13, 0.28) | <0.0001 | 0.19 (0.08, 0.30) | 0.001 |
| 1 | −0.004 (−0.06, 0.05) | 0.89 | 0.01 (−0.04, 0.06) | 0.81 | −0.002 (−0.08, 0.07) | 0.96 |
| 2–3 | −0.01 (−0.06, 0.04) | 0.71 | 0.03 (−0.02, 0.07) | 0.27 | 0.09 (0.02, 0.15) | 0.008 |
| 4–5 | 0.03 (−0.04, 0.10) | 0.42 | 0.03 (−0.03, 0.09) | 0.39 | 0.12 (0.04, 0.20) | 0.004 |
| 6–7 | −0.04 (−0.17, 0.09) | 0.53 | −0.06 (−0.16, 0.04) | 0.22 | −0.05 (−0.18, 0.08) | 0.44 |
| ≥8 | −0.02 (−0.20, 0.17) | 0.86 | 0.01 (−0.13, 0.15) | 0.90 | −0.10 (−0.28, 0.07) | 0.24 |
| Cups/day, linear trend | −0.005 (−0.02, 0.01) | 0.42 | −0.0005 (−0.01, 0.01) | 0.92 | 0.002 (−0.01, 0.01) | 0.79 |
| Reaction Time3 | ||||||
| 0 | Reference | Reference | Reference | |||
| <1 | −1.09 (−3.76, 1.58) | 0.42 | −1.25 (−3.65, 1.15) | 0.31 | 1.37 (−2.08, 4.83) | 0.44 |
| 1 | 3.53 (1.72, 5.35) | 0.0001 | 2.57 (0.99, 4.15) | 0.001 | 2.42 (0.16, 4.68) | 0.04 |
| 2–3 | 3.02 (1.40, 4.64) | 0.0003 | 2.73 (1.34, 4.12) | 0.0001 | 2.71 (0.77, 4.65) | 0.006 |
| 4–5 | 3.73 (1.47, 6.00) | 0.001 | 2.69 (0.85, 4.54) | 0.004 | 3.07 (0.58, 5.56) | 0.02 |
| 6–7 | 3.51 (−0.36, 7.38) | 0.08 | 3.71 (0.69, 6.73) | 0.02 | 5.62 (1.78, 9.47) | 0.004 |
| ≥8 | 3.35 (−2.31, 9.01) | 0.25 | 0.80 (−3.45, 5.05) | 0.71 | 6.23 (0.99, 11.46) | 0.02 |
| Cups/day, linear trend | 0.68 (0.32, 1.03) | 0.0002 | 0.47 (0.19, 0.75) | 0.001 | 0.77 (0.40, 1.15) | <0.0001 |
| Pairs Matching3 | ||||||
| 0 | Reference | Reference | Reference | |||
| <1 | 0.012 (−0.004, 0.029) | 0.15 | −0.010 (−0.025, 0.005) | 0.18 | 0.005 (−0.017, 0.026) | 0.67 |
| 1 | 0.019 (0.008, 0.031) | 0.001 | 0.019 (0.010, 0.029) | <0.0001 | 0.018 (0.004, 0.032) | 0.01 |
| 2–3 | 0.015 (0.005, 0.025) | 0.003 | 0.025 (0.016, 0.033) | <0.0001 | 0.019 (0.007, 0.031) | 0.002 |
| 4–5 | 0.012 (−0.002, 0.026) | 0.09 | 0.011 (−0.001, 0.022) | 0.06 | 0.010 (−0.005, 0.025) | 0.20 |
| 6–7 | −0.008 (−0.032, 0.016) | 0.49 | 0.011 (−0.007, 0.030) | 0.24 | 0.007 (−0.017, 0.031) | 0.55 |
| ≥8 | −0.002 (−0.037, 0.033) | 0.90 | −0.008 (−0.034, 0.018) | 0.53 | 0.039 (0.006, 0.071) | 0.02 |
| Cups/day, linear trend | 0.001 (−0.001, 0.004) | 0.19 | 0.002 (0.00001, 0.004) | 0.05 | 0.003 (0.001, 0.005) | 0.01 |
| Symbol Digit Substitution2 | ||||||
| 0 | Reference | Reference | Reference | |||
| <1 | −0.27 (−0.50, −0.04) | 0.02 | −0.16 (−0.37, 0.05) | 0.14 | −0.18 (−0.49, 0.13) | 0.26 |
| 1 | −0.07 (−0.24, 0.09) | 0.40 | −0.17 (−0.31, −0.03) | 0.02 | −0.29 (−0.49, −0.09) | 0.005 |
| 2–3 | −0.22 (−0.37, −0.07) | 0.003 | −0.23 (−0.36, −0.11) | 0.0002 | −0.24 (−0.41, −0.06) | 0.008 |
| 4–5 | −0.03 (−0.24, 0.17) | 0.74 | −0.22 (−0.38, −0.05) | 0.01 | −0.27 (−0.49, −0.04) | 0.02 |
| 6–7 | −0.33 (−0.70, 0.04) | 0.08 | −0.33 (−0.61, −0.04) | 0.02 | −0.38 (−0.76, −0.01) | 0.04 |
| ≥8 | −1.02 (−1.60, −0.44) | 0.001 | −0.08 (−0.51, 0.34) | 0.70 | −0.94 (−1.47, −0.40) | 0.001 |
| Cups/day, linear trend | −0.05 (−0.09, −0.02) | 0.002 | −0.04 (−0.06, −0.01) | 0.008 | −0.07 (−0.10, −0.03) | 0.0002 |
| Trail A3 (P-interaction = 0.03) | ||||||
| 0 | Reference | Reference | Reference | |||
| <1 | −0.003 (−0.020, 0.013) | 0.70 | 0.012 (−0.003, 0.026) | 0.13 | −0.003 (−0.025, 0.020) | 0.81 |
| 1 | 0.001 (−0.010, 0.013) | 0.83 | 0.006 (−0.004, 0.016) | 0.26 | 0.009 (−0.006, 0.023) | 0.26 |
| 2–3 | 0.004 (−0.007, 0.014) | 0.48 | 0.003 (−0.006, 0.012) | 0.52 | 0.009 (−0.004, 0.022) | 0.18 |
| 4–5 | −0.007 (−0.022, 0.008) | 0.36 | 0.015 (0.003, 0.027) | 0.01 | 0.012 (−0.004, 0.028) | 0.15 |
| 6–7 | 0.002 (−0.024, 0.029) | 0.86 | 0.015 (−0.005, 0.036) | 0.14 | 0.031 (0.004, 0.058) | 0.02 |
| ≥8 | 0.009 (−0.032, 0.050) | 0.68 | 0.006 (−0.023, 0.036) | 0.67 | 0.058 (0.020, 0.096) | 0.003 |
| Cups/day, linear trend | −0.0002 (−0.003, 0.002) | 0.86 | 0.002 (0.00008, 0.004) | 0.04 | 0.004 (0.001, 0.006) | 0.003 |
| Trail B3 (P-interaction = 0.02) | ||||||
| 0 | Reference | Reference | Reference | |||
| <1 | 0.002 (−0.014, 0.018) | 0.84 | 0.011 (−0.004, 0.025) | 0.16 | −0.018 (−0.040, 0.004) | 0.11 |
| 1 | 0.008 (−0.003, 0.020) | 0.15 | 0.012 (0.002, 0.022) | 0.02 | 0.014 (−0.001, 0.028) | 0.06 |
| 2–3 | 0.014 (0.004, 0.025) | 0.006 | 0.011 (0.002, 0.019) | 0.02 | 0.011 (−0.001, 0.024) | 0.07 |
| 4–5 | −0.004 (−0.019, 0.010) | 0.56 | 0.018 (0.006, 0.029) | 0.003 | 0.004 (−0.012, 0.019) | 0.64 |
| 6–7 | −0.005 (−0.031, 0.021) | 0.70 | 0.007 (−0.013, 0.027) | 0.50 | 0.032 (0.006, 0.058) | 0.01 |
| ≥8 | 0.039 (−0.002, 0.080) | 0.06 | 0.019 (−0.010, 0.049) | 0.20 | 0.069 (0.032, 0.106) | 0.0002 |
| Cups/day, linear trend | 0.001 (−0.001, 0.004) | 0.32 | 0.002 (0.0004, 0.004) | 0.02 | 0.004 (0.002, 0.007) | 0.001 |
| Prospective Memory Test2 | ||||||
| OR (95% CI) | P | OR (95% CI) | P | OR (95% CI) | P | |
| 0 | Reference | Reference | Reference | |||
| <1 | 1.15 (1.02, 1.30) | 0.03 | 1.37 (1.22, 1.54) | <0.0001 | 1.28 (1.09, 1.51) | 0.003 |
| 1 | 0.99 (0.92, 1.08) | 0.85 | 1.03 (0.96, 1.10) | 0.47 | 1.04 (0.94, 1.15) | 0.48 |
| 2–3 | 0.99 (0.92, 1.07) | 0.85 | 0.97 (0.91, 1.03) | 0.29 | 1.01 (0.92, 1.11) | 0.81 |
| 4–5 | 0.93 (0.84, 1.04) | 0.20 | 1.02 (0.94, 1.11) | 0.64 | 1.02 (0.91, 1.14) | 0.77 |
| 6–7 | 0.96 (0.80, 1.14) | 0.64 | 1.02 (0.89, 1.18) | 0.74 | 1.00 (0.83, 1.20) | 0.97 |
| ≥8 | 0.99 (0.77, 1.27) | 0.91 | 1.02 (0.84, 1.24) | 0.86 | 0.79 (0.63, 1.00) | 0.05 |
| Cups/day, linear trend | 0.99 (0.97, 1.01) | 0.20 | 1.00 (0.98, 1.01) | 0.62 | 0.99 (0.97, 1.01) | 0.15 |
Results from linear/logistic regressions adjusted for age, sex, smoking, Townsend deprivation index, education, income, employment status, home ownership, self-reported health, waist-to-hip ratio, physical activity, fasting time and intakes of alcohol, water, fish, red meat, fruit, vegetables, and tea (model 3). CMSG: caffeine metabolism score; derived by summing the number of single-nucleotide polymorphism alleles multiplied by their β-coefficients and recalibrated such that it ranged from 0 to 4, with higher scores predicting faster caffeine metabolism.
Positive β-coefficients for FI (difference in 13-point score) and SDS (difference in number of correct substitutions) and OR >1 for PM (correct on first attempt) correspond to higher performance compared with nondrinkers (0 cups/day).
Negative β-coefficients for Pairs [difference in (log-transformed) number of errors], RT (difference in time, seconds, to respond), Trails A and Trails B [difference in (log transformed) time to complete] correspond to higher performance compared with nondrinkers (0 cups/d).
FI, fluid intelligence; Pairs, Pairs Matching; PM, prospective memory; RT, reaction time; SDS, symbol digit substitution.