Table 2. Associations Between the Mediterranean Diet Score and Heart Rate Variability in the Entire Sample.
| Outcome | Difference (%) (95% CI)per 1-unit increment in score*(n = 276) | P value | Means (95% CI) of Log-Transformed HRV Measures | P value§ | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
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| Diet Score = 0-3 (n =78) | Diet Score = 4 (n =58) | Diet Score = 5 (n =65) | Diet Score = 6-9 (n =75) | |||||||||||
| Time-domain | ||||||||||||||
| Model 1: Zygosity and nutritional factors not in the score adjusted† | ||||||||||||||
| SDNN, ms | 1.8 (0.2, 3.4) | 0.03 | 4.77 (4.71, 4.82) | 4.88 (4.81, 4.94) | 4.85 (4.79, 4.91) | 4.87 (4.81, 4.93) | 0.02 | |||||||
| SDANN, ms | 1.6 (−0.1, 3.3) | 0.07 | 4.60 (4.54, 4.66) | 4.69 (4.63, 4.76) | 4.66 (4.60, 4.73) | 4.69 (4.63, 4.75) | 0.04 | |||||||
| SDNNI, ms | 2.9 (1.2, 4.8) | 0.001 | 3.98 (3.91, 4.04) | 4.10 (4.03, 4.17) | 4.13 (4.06, 4.19) | 4.13 (4.06, 4.19) | 0.003 | |||||||
| rMSSD, ms | 3.9 (1.3, 6.5) | 0.003 | 3.37 (3.28, 3.45) | 3.58 (3.48, 3.67) | 3.55 (3.46, 3.64) | 3.55 (3.46, 3.64) | 0.005 | |||||||
| pNN50, % | 10.5 (3.6, 18) | 0.003 | 1.49 (1.27, 1.72) | 1.90 (1.66, 2.15) | 1.87 (1.63, 2.11) | 1.96 (1.74, 2.18) | 0.005 | |||||||
| Model 2: Multivariate adjusted‡ | ||||||||||||||
| SDNN, ms | 1.7 (0.1, 3.4) | 0.04 | 4.73 (4.63, 4.84) | 4.84 (4.74, 4.95) | 4.80 (4.70, 4.90) | 4.83 (4.73, 4.93) | 0.02 | |||||||
| SDANN, ms | 1.6 (−0.1, 3.4) | 0.07 | 4.55 (4.44, 4.67) | 4.65 (4.54, 4.77) | 4.61 (4.50, 4.72) | 4.65 (4.54, 4.75) | 0.03 | |||||||
| SDNNI, ms | 2.7 (1, 4.5) | 0.003 | 3.98 (3.87, 4.09) | 4.10 (3.99, 4.21) | 4.08 (3.98, 4.19) | 4.11 (4.01, 4.22) | 0.006 | |||||||
| rMSSD, ms | 3.8 (1.1, 6.4) | 0.005 | 3.42 (3.26, 3.58) | 3.60 (3.43, 3.76) | 3.57 (3.42, 3.73) | 3.59 (3.44, 3.75) | 0.007 | |||||||
| pNN50, % | 10.1 (3.2, 17.4) | 0.004 | 1.73 (1.32, 2.14) | 2.08 (1.66, 2.50) | 2.01 (1.61, 2.41) | 2.18 (1.78, 2.57) | 0.007 | |||||||
| Frequency-domain | ||||||||||||||
| Model 1: Zygosity and nutritional factors not in the score adjusted† | ||||||||||||||
| TotPow, ms2 | 4.5 (1.1, 7.9) | 0.009 | 9.29 (9.17, 9.41) | 9.54 (9.41, 9.67) | 9.51 (9.39, 9.63) | 9.53 (9.42, 9.65) | 0.003 | |||||||
| ULF, ms2 | 4.1 (0.4, 7.9) | 0.03 | 9.00 (8.87, 9.12) | 9.24 (9.10, 9.38) | 9.18 (9.05, 9.31) | 9.23 (9.10, 9.35) | 0.01 | |||||||
| VLF, ms2 | 5.5 (1.8, 9.5) | 0.004 | 7.41 (7.28, 7.54) | 7.65 (7.51, 7.79) | 7.72 (7.58, 7.85) | 7.67 (7.54, 7.80) | 0.01 | |||||||
| LF, ms2 | 7.9 (2.8, 13.3) | 0.002 | 6.40 (6.23, 6.57) | 6.65 (6.47, 6.84) | 6.80 (6.62, 6.98) | 6.74 (6.57, 6.91) | 0.02 | |||||||
| HF, ms2 | 4.5 (−1.2, 10.6) | 0.12 | 5.12 (4.93, 5.31) | 5.60 (5.39, 5.81) | 5.43 (5.23, 5.63) | 5.40 (5.21, 5.59) | 0.10 | |||||||
| Model 2: Multivariate adjusted‡ | ||||||||||||||
| TotPow, ms2 | 3.6 (0.2, 7.1) | 0.04 | 9.26 (9.05, 9.48) | 9.50 (9.29, 9.72) | 9.42 (9.22, 9.63) | 9.47 (9.27, 9.67) | 0.007 | |||||||
| ULF, ms2 | 3.0 (−0.6, 7.0) | 0.10 | 8.98 (8.74, 9.21) | 9.21 (8.97, 9.45) | 9.11 (8.88, 9.33) | 9.17 (8.95, 9.39) | 0.02 | |||||||
| VLF, ms2 | 4.8 (1.0, 8.7) | 0.012 | 7.45 (7.22, 7.68) | 7.69 (7.46, 7.93) | 7.68 (7.46, 7.90) | 7.68 (7.47, 7.90) | 0.02 | |||||||
| LF, ms2 | 7.7 (2.6, 13.1) | 0.003 | 6.35 (6.04, 6.66) | 6.56 (6.25, 6.87) | 6.66 (6.36, 6.95) | 6.66 (6.37, 6.95) | 0.01 | |||||||
| HF, ms2 | 4.7 (−1.0, 10.8) | 0.11 | 5.12 (4.77, 5.47) | 5.59 (5.23, 5.95) | 5.40 (5.07, 5.74) | 5.43 (5.11, 5.76) | 0.07 | |||||||
*
Values are % differences in geometric means (95% CI) calculated from the β coefficient of the diet score.
†
Total energy intake (continuous), egg consumption (continuous), potato consumption (continuous).
‡
Demographic factors [education (continuous) and marital status (yes/no)]; lifestyle factors [physical activity (continuous), waist-to-hip ratio (continuous)]; coronary risk factors [Framingham risk score (continuous) and plasma triglycerides (continuous)]; use of fish oil supplements (yes/no), β-blockers (yes/no), and other medications (statins, aspirin antihypertensives, and antihyperglycemics) (yes/no).
§
Test for trend across diet groups.