Major Dietary Patterns and Risk of Coronary Heart Disease - Essay Example

The dietary patterns of 44,875 male US health professionals, aged 40-75 y, were derived from their answers to a food frequency questionnaire (FFQ) that was given every two years from 1986 to 1994. Incident coronary heart disease (CHD) (fatal and non-fatal myocardial infarction) was observed in 1089 cases. Factor analysis was conducted to determine dietary patterns based on the 40 food groups listed in the questionnaire. Adjustments for age, smoking, alcohol consumption, level of physical activity, total caloric intake, and other risk factors were also done.
Two major dietary patterns were observed: prudent, which is heavy on vegetables, fruits, fish, and poultry; and western, loaded with red and processed meats, refined grain, desserts, French fries, and dairy. Increased prudent patterns were found to decrease the incidence of CHD while increased western patterns also increased the CHD incidence.
2. Identify what the study is about and its appropriateness (30%)
Previous researches correlated CHD to single nutrients in the diet. This study considered overall dietary patterns in subjects for 8 years and how these relate to the occurrence of CHD within the study period. Diet plays an important role in disease as observed in disease occurrence in countries that have a distinct dietary pattern. The study is appropriate because it considers the interaction of the different components in the diet taking into consideration food preferences and habitual food use. The study is also very appropriate and timely because of the high incidence of CHD in many countries and therefore nutritional intervention by recommending changes in dietary patterns may be more acceptable to the public.
3. Identify exposure, outcome, and confounders (10%)
In this study, exposure refers to the dietary patterns; the outcome is the incidence of CHD and confounders are other risk factors like smoking, alcohol consumption, total caloric intake, age, level of physical activity, genetics. Notably, the researchers did their best to remove the effects of confounders through factor analysis.
4. Method of dietary assessment and its appropriateness (20%)
The dietary assessment came from food consumption data provided in the FFQ. The FFQ had itemized 131 items further grouped into 40 distinct categories. Factor analysis was done to derive dietary patterns. Factor analysis removes effects due to lifestyle and other risk factors, therefore, removing confounding effects. FFQ and factor analysis were appropriate for this type and size of the experiment. FFQ was shown in previous studies to effectively determine dietary preferences while factor analysis is appropriate in determining the statistical significance by minimizing systematic errors contributed by lifestyle.
5. Main strengths and weakness of study (20%)
Strengths. This is the first report on the relationship between dietary patterns and CHD. The study validated earlier reports on the relationship between diet and diseases. Read More