(P12-49-26) Effect of the DASH4D Diet on Serum Potassium in Adults With Type 2 Diabetes and Hypertension: The DASH4D Trial

Objectives: To examine the effects of the Dietary Approaches to Stop Hypertension for Diabetes (DASH4D) diet on serum potassium levels among adults with type 2 diabetes and hypertension, as concerns about hyperkalemia may limit adoption of this potassium-rich dietary pattern.

Methods: The DASH4D randomized crossover feeding trial assessed the effects of a modified DASH-style diet (lower carbohydrates, higher unsaturated fats, and lower potassium than the original DASH diet) and sodium reduction on blood pressure among individuals with type 2 diabetes and hypertension. Participants received 4 isocaloric diets for 5 weeks each in random order: DASH4D diet (3800 mg/day potassium for a 2000 kcal/day diet) or a comparison diet (a typical US diet, 2000 mg/day potassium), each with higher (3600 mg/day) or lower (1500 mg/day) sodium. Total intake of energy and micronutrients was adjusted for weight maintenance. The primary outcome of this analysis was end-of-period serum potassium. We combined the sodium arms to compare the effect of DASH4D diet vs. comparison diet on serum potassium, and tested interactions between diet type and sodium content. Subgroup analyses were conducted by age and baseline chronic kidney disease (CKD, eGFR < 60 mL/min/1.73m²).

Results: A total of 101 participants completed at least one feeding period and had available end-of-period serum potassium. At enrollment, mean (SD) age was 67 (8.7) years, serum potassium was 4.3 (0.4) mmol/L, and eGFR was 80 (19) mL/min/1.73m². During the intervention, 2 participants had hyperkalemia (serum potassium ≥ 5.5 mmol/L confirmed by repeat) and were withdrawn from the study for safety. Compared with the comparison diet, the DASH4D diet increased end-of-period serum potassium by 0.12 mmol/L (95% CI: 0.074, 0.17), with no significant interaction by sodium intake level. While this pattern was consistent across CKD subgroups, DASH4D diet did not significantly change serum potassium for participants below 65 years of age (n = 38, p-interaction = 0.03).

Conclusions: In this randomized feeding trial, the DASH4D diet, nearly doubling the dietary potassium of the comparison diet, led to a modest increase in serum potassium with infrequent hyperkalemia events, supporting the safety of the DASH4D dietary pattern with high potassium content for adults with type 2 diabetes.

Funding Sources: Sheikh Khalifa Stroke Institute, NIDDK, NHLBI