Reference
Rai SK, Fung TT, Lu N, et al. The Dietary Approaches to Stop Hypertension (DASH) diet, Western diet, and risk of gout in men: prospective cohort study. BMJ. 2017;357:j1794.
Design
Prospective cohort study
Objective
To look for associations between the Dietary Approaches to Stop Hypertension (DASH) diet, the Western diet, and risk of gout in men.
Participants
A total of 44,444 men from the ongoing longitudinal Health Professionals Follow-up Study (HPFS) were included in this cohort. In 1986, when HPFS was established, the men were primarily white (91%) and aged 40 to 75. During each 2-year assessment cycle since the HPFS began, there has been a greater than 90% eligibility rate. Only men who provided complete information on dietary patterns and did not have a history of gout were included in this study.
Study Parameters Assessed
Data from food frequency questionnaires were used to generate both a DASH dietary pattern and a Western dietary pattern score for each participant. The DASH dietary pattern is high in fruits, vegetables, nuts, legumes, low-fat dairy products, and whole grains and low in sodium, sweetened beverages, and red and processed meats. A Western dietary pattern is high in red and processed meats, fried foods, simple carbohydrates, and sweets.
Outcome Measures
The primary outcome measure was the risk of gout; risk was assessed by applying the preliminary American College of Rheumatology survey criteria, adjusting for potential confounders (eg, age, body mass index [BMI], hypertension, and alcohol consumption).
Key Findings
Compared to men who had a higher Western dietary pattern score, the men who had a higher DASH dietary pattern had significantly lower risk of developing gout in both age-adjusted and multivariable regression models and after adjusting for other risk factors associated with gout, such as alcohol intake and body mass index (BMI).
The DASH diet is especially intriguing because it addresses common comorbidities associated with gout.
To estimate relative risk, researchers categorized dietary pattern scores into fifths. The gout risk score for men in the highest fifth compared to the lowest fifth was 0.68 (P<0.001) in the DASH group and 1.42 (P=0.005) in the Western diet group. Men who had a higher Western dietary pattern had a significantly increased risk of developing gout. High BMI, high alcohol intake, and high coffee intake were also associated with increased risk. Men in the highest fifth in the DASH group consumed less alcohol and coffee, tended to be older, and had lower BMI.
Practice Implications
Interestingly, this year is the 20th anniversary of the introduction of the Dietary Approaches to Stop Hypertension (DASH) diet, considered an important nutritional advancement in the field of cardiovascular health.1 According to the National Institutes of Health (NIH), compared to the typical American diet, the DASH diet includes more fruits, vegetables, fat-free or low-fat milk and milk products, whole grains, fish, poultry, beans, seeds, and nuts, with less sodium, sweets, sugary beverages, fats, and red meat.2
During the past 2 decades, clinical trials have consistently demonstrated that the DASH diet can help lower blood pressure.1 This present study adds to the emerging body of research that associates the DASH diet with lower serum uric acid levels when compared to the standard American diet, suggesting DASH may be a useful intervention in patients who have gout or are at risk of developing gout.3,4
Gout is a form of arthritis that can cause intense pain, swelling, redness, and inflammation of a joint, often the big toe joint. Approximately 6 million US adults have gout, and it primarily affects men aged 40 to 50.5 The incidence of gout has been steadily increasing in many parts of the world, including the United States.6 This may be due, in part, to the corresponding increase in obesity and poor dietary habits.
In addition to anti-inflammatory over-the-counter medications for acute attacks, clinicians often recommend dietary changes to reduce risk and decrease flare-ups. The “gold standard” recommendation is to avoid purine-rich foods, such as processed meats, gravy, and beer.7 However, some studies indicate that purine-rich foods are not the problem and suggest that refined fructose may be a culprit, specifically in beverages.8,9
The DASH diet is especially intriguing because it addresses common comorbidities associated with gout. Individuals with gout have higher rates of cardiovascular comorbidities, including hypertension, which the DASH diet is specifically designed to address. In addition, those suffering from gout have a 63% increased risk for metabolic syndrome.10,11 As the researchers in this present study point out, although individual dietary risk factors for hyperuricemia and gout have been identified, a “piecemeal approach to modifying the various, yet limited, number of specific dietary risk factors is often ineffective and impractical.”12 In addition, the low-purine diet without guidance regarding healthy calorie replacements can lead to a high-carbohydrate diet, which further increases risk of metabolic syndrome.13
As with any diet, compliance and sustainability are linchpin issues when it comes to efficacy. In one study involving patients with hypertension, the participants actually enjoyed the DASH diet enough that they stated they would be willing to continue it long-term.14
This present study provides further evidence that the typical American diet will exacerbate gout risk and flare-ups and demonstrates that the DASH diet is a viable and sustainable intervention for these patients. It may not be the only diet capable of doing so, but this is the first prospective study suggesting the DASH diet can reduce the risk of gout.
