Low Urinary Potassium Excretion is Associated With Higher Risk of All-Cause Mortality in Patients With Type 2 Diabetes: Results of the Dutch DIALECT Cohort

Low 24 h urinary potassium excretion, reflecting low potassium intake, is associated with premature mortality in the general population.Whether urinary potassium excretion is associated with all-cause mortality in patients with type 2 diabetes is unknown.We performed a prospective cohort study in 654 patients with type 2 diabetes of the Diabetes and Lifestyle Cohort Twente (DIALECT). Sex-specific tertiles of 24 h urinary potassium excretion were analysed in a multivariable Cox regression model with all-cause mortality. The outpatient program of the hospital uses a continuous surveillance system by the municipal registry of death to ensure up-to-date information on the patient's status (alive or deceased). Food frequency questionnaires were used to study associations between urinary potassium excretion and food products.Urinary potassium excretion at baseline was 84 ± 25 mmol·day-1 in males and 65 ± 22 mmol·day-1 in females, corresponding to estimated potassium intakes of 4250 ± 1270 mg·day-1 and 3300 ± 875 mg·day-1. During median follow-up for 5.2 [interquartile range 2.7 - 7.9] years, 96 participants died. In a fully adjusted model, patients in the lowest sex-specific tertile had a higher risk of all-cause mortality, compared with patients in the highest sex-specific tertile (HR: 2.09; 95% CI: 1.06, 4.10; P = 0.03). Patients in the lowest sex-specific tertile consumed less fruits and vegetables, dairy, coffee, and potato products compared with patients in the highest sex-specific tertile (all P 0.05).Low potassium intake is associated with a higher risk of all-cause mortality in Dutch patients with type 2 diabetes. Intervention studies are needed to determine whether potassium supplementation improves longevity in patients with type 2 diabetes.