What diet is most appropriate for a hypertensive and obese patient prior to surgery?

From the Guidelines

For a hypertensive and obese patient preparing for surgery, a low-sodium DASH diet (Dietary Approaches to Stop Hypertension) with caloric restriction is most appropriate. This recommendation is based on the most recent and highest quality study, which emphasizes the importance of weight loss and dietary changes in managing hypertension 1. The DASH diet has been shown to be effective in lowering blood pressure, with an apparent dose–response relationship of about 1 mm Hg per kilogram of weight loss.

Key Components of the Diet

• Emphasize fruits, vegetables, whole grains, lean proteins, and low-fat dairy products
• Limit sodium to less than 2,300 mg daily (ideally 1,500 mg)
• Reduce caloric intake by 500-1000 calories per day to achieve gradual weight loss of 1-2 pounds weekly
• Portion control is essential, with meals consisting of half vegetables, one-quarter lean protein, and one-quarter whole grains
• Avoid processed foods, added sugars, saturated fats, and alcohol

Rationale

The DASH diet is a well-established dietary pattern that has been shown to be effective in lowering blood pressure and improving overall health outcomes 1. By combining the DASH diet with caloric restriction, patients can achieve weight loss and improve their surgical outcomes by reducing anesthetic requirements, decreasing operative time, and lowering risks of wound complications and venous thromboembolism.

Timing and Consultation

The diet should begin at least 2-4 weeks before surgery for optimal benefit, and the patient should consult with their healthcare provider about continuing or adjusting blood pressure medications during this period 1. It is essential to note that lifestyle management is an important component of hypertension treatment, and it can enhance the effectiveness of some antihypertensive medications, promote other aspects of metabolic and vascular health, and generally lead to few adverse effects 1.

From the Research

Diet Recommendations for Hypertensive and Obese Patients

The patient in question has a body mass index (BMI) of 39, which categorizes them as obese, and blood pressure readings of 148/92, indicating hypertension. Given these conditions, the most appropriate diet to recommend would be one that addresses both obesity and hypertension.

Key Considerations

• The patient has no known chronic conditions and takes no medication, making dietary changes a primary approach to managing their blood pressure and weight.
• Family history includes myocardial infarction and stroke, highlighting the importance of addressing cardiovascular risk factors through diet.

Recommended Diet

Based on the evidence, the Dietary Approaches to Stop Hypertension (DASH) diet is a feasible approach for weight loss and controlling blood pressure and hypercholesterolemia 2, 3. The DASH diet has been shown to:

• Significantly lower body weight, BMI, and waist circumference, as well as systolic and diastolic blood pressure 2.
• Reduce total cholesterol, low-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol levels 4.
• Be effective in improving systolic blood pressure and reducing the prevalence of arterial hypertension in adolescents, suggesting its potential benefits across different age groups 5.

Comparison with Other Diets

While a very low-carbohydrate (VLC) diet has been found to lead to greater improvements in systolic blood pressure, glycemic control, and weight compared to the DASH diet in adults with hypertension, prediabetes or type 2 diabetes, and overweight or obesity 6, the DASH diet is specifically designed to address hypertension and has a broader range of benefits, including improving lipid profiles and reducing cardiovascular risk factors.

Implementation

Given the patient's preoperative status, initiating the DASH diet three weeks before surgery could help in managing their blood pressure and weight, potentially reducing surgical risks. The DASH diet emphasizes fruits, vegetables, whole grains, lean protein, and low-fat dairy, which are nutrient-dense and can support overall health and well-being 2, 3.