Original ArticleNut consumption and risk of stroke in US male physicians☆
Introduction
Despite a decline in the rate of stroke in the US,1, 2 it remains a major public health issue and is associated with disability, mortality, and major direct and indirect costs.3, 4 This underscores the importance of prevention strategies aiming at reducing the incidence of stroke given the limited acute treatment options. Hypertension is a major risk factor for stroke5 and can be influenced by modifiable lifestyle factors including diet. Among dietary factors, nuts are important source of macro- and micronutrients with health benefits6 as they are low in sodium and also contain a variety of nutrients including unsaturated fatty acids, and minerals such as magnesium and potassium. Previous studies have suggested that nuts may have beneficial effects on blood pressure,7, 8, 9 lipids,10, 11 and insulin sensitivity.12 In a feeding trial, a Mediterranean diet enriched with 30 g/d of nuts (walnuts – 15 g/d, hazelnuts – 7.5 g/d, and almonds – 7.5 g/d) was associated with reduced blood pressure compared to low-fat diet.13 We have previously reported an inverse relation between nut intake and hypertension in male physicians.14 It is thus possible that these physiologic effects of nuts may confer a lower risk of stroke among people who consume them on a regular basis. However, there is a lack of data on the relation between nut consumption and the risk of total stroke or stroke subtypes. Since omega-3 fatty acids contained in nuts have been shown to inhibit platelet aggregation,15, 16 it is possible that nut consumption may prevent or attenuate the progression of thrombo-embolic events. The current study sought to prospectively examine whether nut consumption is associated with the risk of total stroke and stroke subtypes.
Section snippets
Study population
Participants in this project were drawn from the Physicians’ Health Study (PHS), which is a completed randomized, double-blind, placebo-controlled trial designed to study low-dose aspirin and beta-carotene for the primary prevention of cardiovascular disease and cancer. A detailed description of the PHS has been published previously.17 Each participant gave written informed consent and the Institutional Review Board at Brigham and Women’s Hospital approved the study protocol. Of the total
Results
Table 1 presents the crude baseline characteristics of 21,078 study participants according to categories of nut consumption. The mean age was 54.6 ± 9.5 years (range 40.7–86.7). Higher consumption of nuts was associated with a lower prevalence of hypertension and smoking, and a higher proportion of fruit and vegetable, dairy, and breakfast cereal consumption. During the follow up, 1424 new cases of stroke occurred (1189 ischemic, 219 hemorrhagic, and 16 of undetermined cause). Table 2 provides
Discussion
In this large prospective cohort of apparently healthy men at baseline, we found no evidence for an association between nut consumption and the risk of total or ischemic stroke after an average follow up of 21.1 years. For hemorrhagic stroke, we observed suggestive evidence for a J-shaped relation with nut consumption. Despite advances in medical and surgical treatment, stroke is still associated with major disability and is the 3rd leading cause of death. This underscores the importance of
Conflict of interest
None to disclose.
Acknowledgements
We are indebted to the participants in the PHS for their outstanding commitment and cooperation and to the entire PHS staff for their expert and unfailing assistance.
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2015, NutritionCitation Excerpt :Dietary changes are an integral component of LSM aimed at prevention of CVD. Reduction in the consumption of fats and refined carbohydrates along with increased consumption of fiber, nuts, fruits, and vegetables are associated with improvements in glycemic indices; lipid parameters; weight reduction; reduced risk for diabetes and hypertension; and a lower CV mortality [2,4–11]. Of all these different food components, nuts, particularly pistachios, almonds, and walnuts, are known to have numerous health benefits [12–14].
Consumption of nuts and legumes and risk of stroke: A meta-analysis of prospective cohort studies
2014, Nutrition, Metabolism and Cardiovascular DiseasesCitation Excerpt :Meta-regression analysis showed no variables were significant factors for the association between dietary nut intake and stroke risk. Three studies provided results for stroke types [17,18], and one for total fetal stroke [19]. The SRR for the highest versus lowest level of dietary nut intake was 0.97 (95% CI: 0.84–1.10; Pheterogeneity = 0.838, I2 = 0) for IS and 1.17 (95% CI: 0.54–2.54; Pheterogeneity = 0.036, I2 = 77.3%) for ICH.
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Funding: The Physicians’ Health Study is supported by grants CA-34944, CA-40360, CA-097193, HL-26490 and HL-34595 from the National Institute of Health, Bethesda, MD.