Professor Merlin Thomas Professor and program leader , department of diabetes , Monash University , Melbourne , Victoria .

First published online on 1 November 2024

BACKGROUND

HIGH blood pressure affects more

than a third of adults across the globe . 1 , 2 High blood pressure is the most common reason for primary care visits and for the chronic use of prescription medications . 1 It is also the leading cause of premature death . 3

Exposure to high blood pressure can damage the blood vessels and the tissues they supply , including the heart , brain , eyes , feet and kidneys . In particular , sustained high blood pressure is one of the most common causes of chronic kidney disease ( CKD ), the latter identified by the presence of a persistently reduced eGFR and / or elevated urinary albumin excretion rate ( see box 1 ). 4 This is sometimes known as ‘ hypertensive kidney disease ’ or ‘ hypertensive nephrosclerosis ’. This is a presumptive clinical diagnosis in patients with both longstanding high blood pressure and CKD , which is made after other factors have been discounted ( eg , they do not have another obvious cause such as diabetes or glomerulonephritis ). However , because all forms of kidney disease can raise blood pressure and more than 90 % of patients with CKD will have high blood pressure , it is difficult , if not impossible , to attribute the occurrence

Box 1 . Diagnosis of chronic kidney disease

A diagnosis of chronic kidney disease is defined by abnormalities of kidney structure or function , present for a minimum of three months , with implications for health , including :

• eGFR less than 60mL / min / 1.73m 2 .

• Urinary albumin to creatinine ratio 30mg / g or more .

• Urine sediment abnormalities .

• Persistent haematuria .

• Electrolyte and other abnormalities due to tubular disorders .

• Abnormalities detected by histology .

• Structural abnormalities detected by imaging .

• A history of kidney transplantation . Source : Kidney Disease : Improving Global Outcomes 2

and / or progression of CKD solely to high blood pressure , and vice versa . 4 , 5 Other associated factors are often also present , including obesity , dyslipidaemia , age-related functional decline , genetics , reduced developmental nephron endowment , underlying primary kidney disease or multisystem diseases like diabetes and atherosclerosis . Secondary high blood pressure then enhances their effects on the kidney and increases the risk of poor clinical outcomes , including the need for hospitalisation , dialysis , and death .

Rather than ( imprecisely ) labelling this condition ‘ hypertensive kidney disease ’, it has been suggested that

this term should now be abandoned . 4 Just as we use the term ‘ CVD ’ in those with high blood pressure who have had a heart attack or stroke , it is more appropriate to simply diagnose ‘ CKD ’, and to undertake multifactorial strategies to protect their kidneys , lower their cardiovascular risk and improve clinical outcomes . Since chronic kidney function loss is irreversible and is related to significant morbidity and death , there is an urgent need to identify , correctly diagnose and manage CKD at an early stage , in addition to controlling their blood pressure .

Equally , rather than using the term ‘ hypertension ’, which is generally

defined by a single threshold , the term ‘ high blood pressure ’ is now preferred to denote individuals with a blood pressure above a target appropriate for them or people like them . 6 This is particularly important in CKD , as appropriate blood pressure targets are different from those recommended for the general population . 6

This How to Treat describes how to approach the management of CKD in non-diabetic patients with high blood pressure , including diagnosis , investigations , treatment and prognosis . It aims to ensure GPs can screen for CKD in all their patents with high blood pressure , and when identified can initiate appropriate investigations , treatment and when necessary , timely referral for specialist support . The management of patients with CKD in type 2 diabetes is described in a previous How to Treat . 7

EPIDEMIOLOGY

HIGH blood pressure affects approximately a third of the general adult population . 1 CKD is also observed in 10-15 % of adults worldwide . 8 So unsurprisingly , these conditions often coexist and are clearly interrelated . Population-based studies show that the prevalence of high blood