You may have recently received a notification from the surgery that you have a condition called Chronic Kidney Disease (CKD). The following information will explain what that means.

Firstly, please be reassured that if you have received this information as a text, then your results have been assessed by a clinician as being at very low risk of any immediate significant health consequences and at this time your management involves simple monitoring. There are however some actions you can undertake to reduce risk of health consequences associated with CKD, and these will be outlined below.

What is Chronic Kidney Disease?

Your kidneys filter your blood, removing chemical waste (including medications) and excess water, resulting in the production of urine. This urine is then stored in your bladder until the next time you go to the toilet.

We can measure this filtering function through a blood test. This allows us to calculate an estimated filtration rate (eGFR). We also check your urine for the amount of protein it contains. CKD diagnosis is based on these calculations. If your eGFR dips below a certain level on three consecutive tests, then we diagnose this as Chronic Kidney Disease. There are various stages of CKD. We only start monitoring blood/urine tests at CKD stage 3.

Please note that eGFR tests can vary a lot from one test to the next – a set of results over a few years can look more like a Yo-yo, than a steady slope. It is the trend that is important. A sudden change in the levels for no apparent reason will most likely initially result in a repeat test request.

What causes CKD?

Like many of the rest of our body’s functions, there can be a gradual loss of kidney function as we age. For most of us CKD would be better described as Chronic Kidney Decline. Because we start our lives with essentially an overcapacity of kidney function, we can lose a lot of function before we notice any health problems. So, CKD that starts in our 70s, 80s or 90s is very unlikely to have any noticeable effect on our either quality or quantity of life. If you develop CKD younger than this then there is a small possibility that your slow loss of function will eventually require more kidney investigations and support. Younger age at onset may also indicate that other health conditions are affecting the kidney function.

The commonest other health condition associated with CKD is Diabetes. Good diabetic control as well as blood pressure control is essential to reduce health risks associated with this. If you are also diabetic your CKD monitoring will be part of your diabetic monitoring.

Will I have any symptoms?

It is very unlikely that you will have ANY symptoms of 02 unless it were to become quite advanced.  We would already have contacted you to discuss further investigations/referral to kidney specialist if your filtration rates had declined to a point where this might be possible.

CKD and Medication

Many medications are dependent on the kidney to remove them from your body. If this is not done, then the medication may accumulate in your blood stream. If your filtration rate is below a certain level, then the dose of some medications will be reduced.  Different medications are changed at different filtration levels. Our pharmacists may contact you to discuss this. A common example of this is Anticoagulants used in the risk management of Atrial Fibrillation.

When we are ill with for example an infection, or having surgery, we are at risk of dehydration and our Kidneys can show signs of increased stress (a drop in eGFR), which likely recovers as we recover from that illness. In anticipation of this stress to the kidneys it is recommended that some medications are reduced or stopped when we are unwell for other reasons. These are called sick day rules.

CKD, Cardiovascular disease, and statins

Kidneys naturally have a very high blood flow rate. So, CKD may be an early sign of cardiovascular disease. Taking a statin will not reduce the rate of progression of CKD but it may be a benefit to your overall risk of cardiovascular disease. We also know that Blood pressure control in CKD patients is important to overall cardiovascular risk, while not directly reducing the change in CKD. Guidelines are now to offer all patients a statin to try and get their ‘Bad cholesterol’ down.

Monitoring

Depending on the last eGFR you had you will be booked for a monitoring test (blood and urine test) in 12, 6 or 3 months. Please note – if you are being monitored for other health conditions, such as diabetes or hypertension, your tests will be ‘combined’ if at all possible, into a single annual test if appropriate.

To achieve the least variation in tests please try and avoid meat/high protein foods and heavy exercise the day before the blood test and provide a urine sample of the first pass of urine of the day.

Will I be routinely referred to a Kidney specialist?

As overall kidney function remains perfectly adequate despite a slow kidney function decline over many years most patients will never need to see a kidney specialist. If the monitoring detects a more rapid decline, then we will refer for advice. It is also possible to estimate a risk of needing renal-replacement using the ‘4-variable Kidney Failure risk equation’. If the 5-year risk is calculated at more than 5% then a patient is referred to the Renal team for review.

Medication Sick Day Rules

When we are ill, we often reduce our fluid and dietary intake when the illness is at its worst.  We may also lose fluid through vomiting or diarrhoea or sweating. This can lead to dehydration and can make it more difficult for our kidneys to remove chemical waste and medication from our blood stream, making us more unwell.

In view of this it is a good safety measure to temporarily stop medication that either increases water loss through the kidneys (worsening the dehydration) or medication that is particularly dependent on kidney excretion.

These medications include:

• Diuretics – eg Furosemide, Bendroflumethiazide, Bumetanide.
• ACE inhibitors – medications ending in ‘PRIL such as Ramapril, Enalapril or Lisinopril
• ARB’s – medications ending in ‘Sartan – such as losartan, candesartan.
• Ibuprofen or Naproxen (pain killers)
• Diabetic medication – specifically Metformin and ‘flozins such as dapagliflozin and empagliflozin

This is not an exhaustive list, and you may be told specifically about medication you are taking.

These medications have long lasting positive effects, so you are very unlikely to suffer any health consequences if you do not take them for a few days. Once your symptoms have improved and you are eating and drinking regularly for 1-2 days you can restart the medication.