Association of Nut Consumption with Total and Cause-Specific Mortality

1. Association of Nut Consumption with Total and Cause-Specific Mortality Gabrielle Sherer Cardiovascular Risk Reduction Jeff LuckringMS, RD

2. Citation Bao Y, Han J, Hu F, et al. Association of Nut Consumption with Total and Cause-Specific Mortality. N Engl J Med. 2013; 369:2001-2011

3. Background Nuts! • Unsaturated fatty acids • Fiber • Vitamins • Minerals • Antioxidants • Sterols

4. Background Reductions in: • Blood cholesterol • Oxidative stress • Inflammation • Visceral adiposity • Hyperglycemia • Insulin resistance • Endothelial dysfunction Reduced risks of: • CHD • DM2 • Metabolic syndrome • Colon cancer • HTN • Gallstone disease • Diverticulitis • Death from inflammatory diseases

5. Objective Unknown: relationship btw nut consumption and total mortality Examine the association of nut consumption with total and cause specificmortality in two large, independent cohort studies of nurses and other health professionals.

6. Design • Prospective cohort study • Repeated measures of diet • separate data on peanuts and tree nuts • Adj confounding variables • 30 years of f/u • data on 27,000+ deaths

7. Participants & Setting • Nurses’ Health Study • 121,700 female nurses  n=76,464 • from 11 U.S. states • enrolled in 1976 • Health Professionals Follow-up Study • 51,529 male health professionals  n= 42,498 • from all 50 states • enrolled in 1986 • Exclusion: • h/o Cancer, CHD, CVA, DM, smoking • 40<BMI<18.5

8. Methods • F/U questionnaire every other yr • Baseline: year of first validated food frequency questionnaire • How often was a 1 oz serving of nuts consumed? • Subsequent questionnaires split reporting of nut consumption into peanuts and other nuts. • Systematic searches of vital records of states and National Death Index • Blinded Physician-COD using International Classification of Diseases

9. Outcome Measures • Primary Endpoint: death from any cause • Nut consumption : • never or almost never • one to three times a month • once a week • two to four times a week • five or six times a week • once a day • two or three times a day • four to six times a day • more than six times a day

10. Statistical Analysis • Cumulative average of nut consumption • Suspended updating of dietary variables when participants reported dxof CVA, CHD, angina, DM, or cancer • Cox proportional-hazards models adj for predictors of death • hazard ratios and 95% confidence intervals • Wald test • P values for trend • Restricted-cubic-spline regression • model the association • Controlled for intake of Na and oil

11. Results • More frequent nut consumption- leaner, less likely to smoke, more likely to exercise, more likely to use multivit/min, ate more fruit/veg, drank more etoh • Significant inverse association btw frequency of nut consumption and total mortality among women and men

14. Conclusions • Consume nuts 7+ times per week – 20% lower death rate • Consistent with smaller studies • Strengths: large sample, repeated measures of intake over 30yrs, measures to min confounding factors and reverse causality • Limitations: self reporting of intake (avg), nut preparation not considered, cohort of health professionals (metabolic processes unlikely to differ from gen pop).

15. Implications for Clinical Practice • Recommend nut consumption • 2-4 x per week • Replace foods high in sat fat • Focus on portion size -1 oz(1/4 cup) • Consider preparation