Table 1.
Sample characteristics by chocolate intake of 20,922 men and women of the EPIC-Norfolk cohort at the study baseline (1993–1997) and incident heart failure at respective follow up March 2009.
| Quintiles of daily chocolate intake | Quintile 1 (n = 4236) | Quintile 2 (n = 3521) | Quintile 3 (n = 4386) | Quintile 4 (n = 4582) | Quintile 5 (n = 4198) | p-value* |
|---|---|---|---|---|---|---|
| Range (g/day) | 0 | 0.6–3.4 | 3.5–6.9 | 7.0–15.5 | 15.6–98.8 | |
| Median (IQR) (g/day) | ||||||
| Chocolate intake | 0 | 0.8 (0.6, 1.4) | 4.1 (4.1, 4.9) | 8.7 (8.0, 12.0) | 24.9 (22.1, 39.5) | |
| Chocolate singles | 0 | 0.6 (0.6,1.1) | 0.6 (0, 1.1) | 1.1 (0, 3.4) | 1.1 (0.6, 3.4) | |
| Chocolate bars | 0 | 0 | 3.5 (3.5, 3.5) | 7.0 (3.5, 7.0) | 21.5 (21.5, 21.5) | |
| Chocolate beverages | 0 | 0 (0, 0.8) | 0 (0, 0.8) | 0 (0, 5.2) | 0 (0, 5.2) | |
| Sex, women | 53 (2236) | 56 (1962) | 56 (2441) | 54 (2455) | 50 (2090) | <0.001 |
| Age, years | 60 ± 9 | 60 ± 9 | 57 ± 9 | 58 ± 9 | 57 ± 9 | <0.001 |
| Body mass index, kg/m2 | 26.4 ± 4.0 | 26.2 ± 3.8 | 26.3 ± 3.6 | 26.2 ± 3.8 | 26.1 ± 3.7 | <0.001 |
| Current smoker | 10 (428) | 10 (369) | 11 (486) | 12 (547) | 13 (564) | <0.001 |
| Self-reported diabetes | 6 (235) | 2 (60) | 1 (60) | 1 (47) | 1 (31) | <0.001 |
| Self-reported hypertension | 16 (691) | 14 (494) | 13 (590) | 13 (587) | 12 (495) | <0.001 |
| Self-reported myocardial infarction | 4 (168) | 3 (108) | 2 (108) | 2 (114) | 2 (92) | <0.001 |
| Self-reported arrhythmia | 6 (239) | 6 (194) | 4 (190) | 5 (225) | 5 (213) | 0.050 |
| Total cholesterol, mmol/L | 6.2 ± 1.2 | 6.2 ± 1.1 | 6.1 ± 1.1 | 6.2 ± 1.2 | 6.1 ± 1.2 | <0.001 |
| Systolic blood pressure, mmHg | 137 ± 18 | 136 ± 18 | 135 ± 18 | 135 ± 18 | 134 ± 17 | <0.001 |
| Heart rate, beats/minute | 71 ± 12 | 71 ± 12 | 70 ± 12 | 71 ± 12 | 71 ± 11 | 0.79 |
| Social class | <0.001 | |||||
| I | 6 (268) | 8 (285) | 7 (318) | 7 (333) | 6 (271) | |
| II | 34 (1429) | 41 (1433) | 39 (1698) | 35 (1630) | 36 (1496) | |
| III non-manual | 16 (685) | 17 (590) | 16 (692) | 16 (754) | 17 (739) | |
| III manual | 25 (1041) | 20 (712) | 23 (1008) | 23 (1078) | 24 (996) | |
| IV | 15 (630) | 11 (398) | 13 (562) | 13 (618) | 13 (556) | |
| V | 4 (183) | 3 (103) | 2 (108) | 4 (168) | 3 (140) | |
| Education | <0.001 | |||||
| No qualification | 40 (1702) | 34 (1181) | 34 (1499) | 35 (1616) | 34 (1445) | |
| O-level | 10 (420) | 10 (365) | 11 (464) | 11 (514) | 11 (448) | |
| A-level | 40 (1682) | 41 (1440) | 41 (1799) | 41 (1867) | 43 (1784) | |
| Degree or higher | 10 (432) | 15 (535) | 14 (624) | 13 (584) | 12 (521) | |
| Physical activity | <0.001 | |||||
| Inactive | 34 (1420) | 29 (1037) | 27 (1196) | 27 (1256) | 28 (1158) | |
| Moderately inactive | 27 (1153) | 30 (1070) | 29 (1283) | 30 (1375) | 28 (1167) | |
| Moderately active | 21 (907) | 23 (818) | 24 (1057) | 23 (1048) | 24 (1023) | |
| Active | 18 (756) | 17 (596) | 19 (850) | 20 (902) | 20 (850) | |
| Energy intake by FFQ, kJ/day | 7812 ± 2291 | 8104 ± 2265 | 8339 ± 2309 | 8928 ± 2411 | 9926 ± 2666 | <0.001 |
| Alcohol by FFQ, g/day | 8.8 ± 14.4 | 9.3 ± 13.0 | 9.2 ± 13.1 | 8.3 ± 12.0 | 8.4 ± 12.2 | <0.001 |
| Incident heart failure | 7 (302) | 6 (201) | 5 (206) | 5 (221) | 4 (171) | <0.001 |
Data are presented as mean ± SD, percentage (number) or median (IQR).
*P-value determined by analysis of variance (ANOVA) for continuous variables and χ2 test for categorical variables for differences among groups.