Table 3.
Risk of Coronary Heart Disease by Quintiles of Nitrate Intake in the NHS (1986–2012) *
| Variable | Quintile 1 (<86 mg/d) |
Quintile 2 (86–117 mg/d) |
Quintile 3 (118–150 mg/d) |
Quintile 4 (151–195 mg/d) |
Quintile 5 (>195 mg/d) |
P-value for trend |
|---|---|---|---|---|---|---|
| Number of cases | 493 | 440 | 419 | 465 | 450 | … |
| Person-years | 293,249 | 294,919 | 295,097 | 295,112 | 294,658 | … |
| RR (95% CI) | ||||||
| Age-adjusted |
1 [Reference] |
0.88 (0.77,1.00) |
0.78 (0.69,0.89) |
0.83 (0.73,0.94) |
0.77 (0.68,0.87) |
0.0002 |
| †Model 1 |
1 [Reference] |
0.95 (0.84,1.09) |
0.89 (0.79, 1.02) |
0.97 (0.85,1.10) |
0.91 (0.80,1.04) |
0.27 |
| ‡Model 2 |
1 [Reference] |
0.99 (0.87,1.13) |
0.95 (0.83,1.08) |
1.06 (0.93,1.21) |
1.04 (0.91,1.20) |
0.35 |
| §Model 3 |
1 [Reference] |
0.98 (0.98,1.12) |
0.94 (0.83,1.08) |
1.05 (0.92,1.19) |
1.02 (0.89,1.17) |
0.55 |
Abbreviations: ellipses, data no applicable; RR, relative risk; CI, Confidence Intervals
*
Intake calculated using cumulative average (average of all available intake data from FFQ completed before each 2-year period at risk)
†
Model 1: Multivariable analyses stratified by age in months and period at risk, and adjusted for smoking status, race, body mass index and physical activity.
‡
Model 2: Model 1, adjusted for the Alternative Healthy Eating Index, excluding vegetables and fruit.
§
Model 3: Model 2, adjusted for hypertension, high cholesterol, diabetes and family history of myocardial infarction.