Abstract MP062: Dietary Protein Intake and Coronary Heart Disease in Middle-Aged Adults: Results from the ARIC Study
Authors: Haring Bernhard , Gronroos Noelle N , Alonso Alvaro , von Ballmoos Moritz W , Nettleton Jennifer A , Selvin Elizabeth 
Published: July 2021

Background:
Dietary protein intake in the U.S. has increased substantially over the past decades, but studies examining the relationship between protein intake and coronary heart disease (CHD) are sparse. Our objective was to assess the relationship of total protein, animal protein, and vegetable protein with risk of CHD in a large, community-based cohort.

Research Design and Methods:
Participants from the Atherosclerosis Risk in Communities Study (ARIC) who were free of cardiovascular disease at baseline (1987-89) were included in this analysis. Dietary intake was assessed by an interviewer-administered 66-item food frequency questionnaire at baseline and again approximately 6 years later. CHD was defined as a definite or probable myocardial infarction, death from CHD, a cardiac procedure, or electrocardiographic evidence of a silent myocardial infarction. Cox proportional hazards models were used to calculate multivariable hazard ratios and 95% CIs where exposure status was a time-dependent covariate with baseline dietary data used as the exposure for the period between baseline and visit 3, and the average intake of visits 1 and 3 afterwards.

Results:
With a median follow up time of 19.8 years there were 1,611 CHD events among 10,395 eligible participants. We did not observe significant associations between total protein, animal protein, or vegetable protein intake and incident CHD in either the minimally adjusted or fully adjusted models (
Table
). Similarly, hazard ratios for substituting 50 grams of vegetable protein for animal protein did not result in a significant risk change (HR=0.97, 95% CI: 0.56-1.69).

Conclusion:
In this large community-based cohort intake of total protein, animal-derived protein, and plant-derived protein were not significantly associated with incident CHD. Studies using whole foods (e.g., chicken, eggs, legumes) as protein exposures may allow for a more nuanced analysis of the protein-CHD relationship.

Adjusted hazard ratios (95% CI) for incident CHD by quartile of protein intake at baseline (1987-89)

Total Protein Intake
Animal Protein Intake
Vegetable Protein Intake

Grams/Day
Incident CHD Cases (n)

HR (95% CI) Min Adj

‡

HR (95% CI) Fully Adj
*

Grams/Day
Incident CHD Cases (n)

HR (95% CI) Min Adj

‡

HR (95% CI) Fully Adj
*

Grams/Day
Incident CHD Cases (n)

HR (95% CI) Min Adj

‡

HR (95% CI) Fully Adj
*

Q1
<52.3
378 (2,598)
1 (ref)
1 (ref)
<37.4
384 (2,599)
1 (ref)
1 (ref)
<12.3
354 (2,599)
1 (ref)
1 (ref)

Q2
52.3-67.9
369 (2,599)
0.95 (0.82-1.10)
0.94 (0.81-1.10)
37.4-50.4
354 (2,598)
0.85 (0.74-0.98)
0.83 (0.72-0.97)
12.3-16.5
385 (2,598)
0.92 (0.79-1.07)
0.95 (0.81-1.10)

Q3
67.9-86.0
418 (2,599)
0.97 (0.82-1.14)
0.95 (0.80-1.13)
50.4-65.9
433 (2,600)
0.91 (0.78-1.06)
0.89 (0.76-1.05)
16.5-21.8
408 (2,599)
1.06 (0.91-1.24)
1.11 (0.95-1.31)

Q4
>86.0
446 (2,599)
0.97 (0.79-1.19)
0.90 (0.71-1.14)
>65.9
440 (2,598)
1.01 (0.85-1.20)
0.91 (0.74-1.12)
>21.8
464 (2,599)
0.91 (0.75-1.10)
0.96 (0.79-1.17)

p for trend

0.83
0.47

0.80
0.47

0.76
0.73

‡

Adjustment for age, sex, and race.

*

Additional adjustment for center and baseline levels of education, hypertension, type 2 diabetes, LDL, HDL, triglycerides, waist-to-hip ratio, physical activity, smoking status, alcohol intake, and time varying levels of total energy intake, and total carbohydrate intake.