Table 2.
Breakfast frequency and multivariable-adjusted hazard ratios of myocardial infarction (MI) and coronary heart disease (CAD) with 95% confidence intervals.
| Breakfast Frequency |
|||
|---|---|---|---|
| Not-daily (0−6 days/week) (n = 597) | Daily (7 days/week) (n = 3473) | P-value | |
| MI cases (n) | 111 | 684 | |
| Person-time (years, %) | 8,139.14 (14.98) | 461,93.43 (85.02) | |
| Adjusted for age and sex: HR (95% CI) | 1.04 (0.85, 1.27) | 1 (ref) | 0.72 |
| + Demographic factorsa | 1.01 (0.82, 1.24) | 1 (ref) | 0.92 |
| + Lifestyle and mental health factorsb | 1.01 (0.82, 1.24) | 1 (ref) | 0.92 |
| + Dietary factorsc(final model) | 1.01 (0.82, 1.28) | 1 (ref) | 0.91 |
| Sensitivity analysis: Additional adjustmentd | 1.02 (0.81, 1.29) | 1 (ref) | 0.90 |
| Sensitivity analysis: Excluding early eventse | |||
| Cases (n) | 106 | 609 | |
| Person-time (years, %) | 8110.3 (14.98) | 46036.08 (85.02) | |
| HRc (95% CI) | 1.08 (0.85, 1.37) | 1 (ref) | 0.54 |
| CAD cases (n) | 228 | 1389 | |
| Person-time (years, %) | 7,478.38 (14.99) | 42,424.34 (85.01) | |
| Adjusted for age and sex: HR (95% CI) | 1.01 (0.90, 1.20) | 1 (ref) | 0.58 |
| + Demographic factorsa | 1.00 (0.87, 1.16) | 1 (ref) | 0.95 |
| + Lifestyle and mental health factorsb | 1.00 (0.87, 1.16) | 1 (ref) | 0.99 |
| + Dietary factorsc(final model) | 0.99 (0.85, 1.17) | 1 (ref) | 0.94 |
| Sensitivity analysis: Additional adjustmentd | 0.98 (0.84, 1.15) | 1 (ref) | 0.81 |
| Sensitivity analysis: Excluding early eventse | |||
| Cases (n) | 210 | 1225 | |
| Person-time (years, %) | 7437.25 (14.99) | 42188.64 (85.01) | |
| HRc (95% CI) | 1.04 (0.88, 1.22) | 1 (ref) | 0.68 |
Abbreviations: BMI, Body Mass Index; CI, confidence interval; HR, hazard ratio.
Data are from a multivariable-adjusted analysis using Cox proportional hazard regression.
In addition to age (years) and sex (female, male), this model is adjusted for demographic factors: marital status (married, not married), largest racial group in the CHS (no, yes), education (≤high school graduation, >high school graduation), and annual household income (<$25,000, $25,000-$49,999, ≥$50,000).
In addition to age, sex, and demographic factors, this model is further adjusted for lifestyle and mental health factors: smoking status (never, former, current), alcohol (number of alcoholic beverages/week; 0, <7, 7−14, >14), exercise (none/low, moderate/high), and Centre for Epidemiological Studies-Depression Scale score (high: ≥10, low: <10).
In addition to age, sex, demographic, lifestyle, and mental health factors, this model is further adjusted for dietary factors: fruit and vegetable intake (<3, ≥3 servings/day), breakfast timing (before 07:00, 07:00−09:00, after 09:00), meal frequency (<3, ≥3 meals/day), and snacks after dinner (yes, no). This model (bolded) is the main model reported for this analysis.
In addition to age, sex, demographic, lifestyle, mental health, and dietary factors, this model is further adjusted for BMI (kg/m2) fasting insulin, fasting glucose, and hypercholesterolemia.
Events within the study’s first two years were excluded to help reduce the possibility of reverse causation from underlying illness affecting breakfast habits at baseline. In this analysis, participants who had early events did not contribute any follow-up. Participants who were event-free at 2 years contributed person-time from year 2 onward.