Relationship between a diagnosis of kidney failure and heart diseases in patients with hyperkalaemia.

Objectives: This study seeks to determine the association between kidney failure and heart diseases by examining how they influence the diagnosis of hyperkalaemia.

Methods: We employ a fuzzy regression discontinuity design (RDD) by harnessing the inherent threshold in potassium levels, which serves as a diagnostic criterion for hyperkalaemia. Simultaneously, we utilize patient diagnosis data related to kidney failure and heart diseases. This approach allows us to evaluate the causal impact of both diagnoses on hyperkalaemia.

Results: Significant overall increases in the risk of developing hyperkalaemia are evident subsequent to a diagnosis of kidney failure or heart disease. The study finds that the probability of receiving a kidney failure diagnosis increases by 11.2% regarding a cut-off of 6 mEq/L of potassium. In addition, there is an 6.8% likelihood of experiencing hyperkalaemia in the case of a prior diagnosis of hypertension, and an 8.8% probability in the case of a diagnosis of depression. The findings remain robust when considering alternative parametric and non-parametric specifications as well as placebo tests.

Conclusions: This study provides new empirical insights into the causal impact of kidney failure and heart disease, underscoring the significance of monitoring such patients to prevent serious complications in the future.