Hypertension, the kidney, and cardiovascular risk

Hypertension and chronic kidney disease are both independent risk factors for first or subsequent cardiovascular events. Blood pressure-lowering therapy is recommended in patients with hypertension and chronic kidney disease, in order to reduce the risk of cardiovascular disease and kidney failure. Ideally, blood pressure targets are reached in all patients but in clinical practice this is often not achieved. Therefore, more insight in the prevalence of potential modifiable factors related to hypertension (i.e. underlying diseases and lifestyle factors) and hypertension-related cardiovascular risk is imperative in high-risk patients, such as patients with cardiovascular disease or vascular risk factors. Because chronic kidney disease is related to development of cardiovascular disease, it is relevant to identify new kidney-related risk factors for cardiovascular events as this may enable further identification of patients at high cardiovascular risk. In this thesis we show that there is a high prevalence of potential modifiable factors of hypertension in patients with uncontrolled hypertension, including underlying medical conditions and lifestyle factors. Follow-up of patients with cardiovascular disease demonstrated that blood pressure control does not improve time. We also show that one in every eleven patients with cardiovascular disease has apparent resistant hypertension, which is defined by persisting high blood pressure despite blood pressure-lowering drug use from multiple classes. Patients with apparent resistant hypertension are at higher risk to die from subsequent cardiovascular events. These results demonstrate that uncontrolled hypertension has considerable impact on current clinical practice because of the high prevalence and associated increased vascular risk.
Large kidney length in overall, is related to higher of cardiovascular events in patients at high cardiovascular risk. Furthermore, high ratios of kidney function to kidney size are related to higher risk of mortality and kidney function decline. Thus, kidney size may serve as marker to identify patients at high vascular risk.