. 2021 Feb 5;14(6):1524–1534. doi: 10.1093/ckj/sfab032

Table 5.

Categorizing risk based on IDF-DAR risk categories

Risk level	Low–moderate risk	High risk	Very high risk
Advice	Listen to medical advice	Should not fast	Must not fast
CKD stage	Stages 1–3 with stable kidney function	Stages 1–3 with unstable kidney function^a	Stages 4–5 (non-dialysis)^b Patients on all forms of HD and PD Stages 3–5 patients with a history of pre-existing cardiovascular disease
Other groups	CKD patients prone to urinary tract infections or stone formation	CKD patients with known electrolyte abnormalities. Patients at risk of dehydration due to fluid restriction requirements or need for diuretics. Patients on ACE-Is/ARBs, SGLT2 inhibitors and mineralocorticoid receptor antagonists	Patients on tolvaptan Pregnant CKD patients

Risk level

Low–moderate risk

High risk

Very high risk

Advice

Listen to medical advice

Should not fast

Must not fast

CKD stage

Stages 1–3 with stable kidney function

Stages 1–3 with unstable kidney function^a

Stages 4–5 (non-dialysis)^b

Patients on all forms of HD and PD

Stages 3–5 patients with a history of pre-existing cardiovascular disease

Other groups

CKD patients prone to urinary tract infections or stone formation

CKD patients with known electrolyte abnormalities. Patients at risk of dehydration due to fluid restriction requirements or need for diuretics. Patients on ACE-Is/ARBs, SGLT2 inhibitors and mineralocorticoid receptor antagonists

Patients on tolvaptan

Pregnant CKD patients

Unstable patients includes those with rapidly declining GFR, history of fluid overload and frailty.

Although HD and PD patients would be considered very high risk, a select group may be able to fast following risk stratification and counselling. Factors to consider include residual renal function, fluid balance, potassium >6.0 mmol/L, motivation, compliance with medical advice, considered alternatives to fasting and winter fasting.