– There are no rules for preventing kidney disease because the kidneys never get sick separately. To paraphrase the saying “in a healthy body, a healthy mind” should be said that “in a healthy body, healthy kidneys”. With prof. Tomasz Stompór, we talk about how to care for “the filter of our body”.
Professor, experts are sounding the alarm – it is estimated that 4,2 million Poles suffer from kidney diseases, and most do not know about it. Who is at risk?
Groups of people at high risk of kidney disease have been identified fairly well. These include, in the first place, people with diabetes of both types (type 1 and 2). It can be assumed that about 30-40% of all diabetic patients suffer from kidney damage of varying degrees. This means, therefore, that diabetic kidney disease is the leading cause of kidney damage: in Poland (where – as it is estimated – up to 10% of the population, i.e. approx. Three million people suffer from kidney disease), no less than a million of them have a diabetic kidney disease. kidney. It is also the most common disease diagnosed in dialysis patients.
Other perfectly identified risk factors for kidney damage include: arterial hypertension, obesity, and the presence of kidney diseases in members of the immediate family. Age is, of course, a particular risk factor – in people over 65 years of age, the incidence of clinically significant kidney damage increases by leaps and bounds, exceeding 20%.
The so-called episodes are also an important cause. acute kidney injury – these are short-term periods of significant deterioration of kidney function due to e.g. dehydration, medications, contrast agents, severe infections, which in theory disappear after the causative factor has subsided. However, a few such episodes, even over many years, can have a “cumulative” effect and result in chronic kidney damage.
The so-called Chronic cardio-renal syndrome: People with chronic heart disease also gradually deteriorate in their kidney function. I would also identify one more specific risk group – people with chronically impaired urinary flow – these are mainly men with prostate enlargement, including the benign prostate.
Does the way we eat affect the kidneys?
Of course. As I mentioned, diabetes, high blood pressure and obesity are important risk factors for developing kidney disease. Each of them, in turn, is largely diet-related diseases. Both the excessive supply of calories as well as fats and carbohydrates translate (directly or indirectly) into the risk of developing kidney disease. Table salt and phosphates are very important dietary threats to the kidneys. The latter, however, serving to build bones and being a material for the synthesis of the physiological fuel, which is ATP, are very toxic when consumed in excess.
There are a lot of them in, among others, highly processed and preserved products, and sparkling drinks. Fructose (ubiquitous in similar product categories as listed above) is also very harmful to the kidneys. In some situations, excess oxalic acid and even high doses of vitamin C can be harmful. Speaking of which, I am confident that healthy people (and most patients suffering from chronic diseases) do not need any dietary supplements. The end of the 90s is, among others the famous and tragic history of Chinese herbal nephropathy – dozens of young women who developed severe and irreversible kidney failure requiring dialysis after taking herbal preparations to aid weight loss, imported from China.
Recently, high-protein and ketogenic diets have been enjoying great popularity – do they serve our kidneys?
A high-protein diet definitely increases the risk of progression, i.e. worsening of already diagnosed kidney disease. It is more difficult to make such categorical statements about the risk of developing kidney damage in healthy people. Nevertheless, most observational studies show an association between high protein intake in the diet and the risk of chronic kidney disease. This is due to several facts. First, a high-protein diet is also a diet full of phosphate.
Second, a high-protein diet is acidic, which promotes kidney damage. Thirdly, high protein content in the diet leads to changes in the composition of intestinal bacteria – the advantage is those that can produce toxic substances from dietary components, then absorbed from the gastrointestinal tract damage not only the kidneys, but also the heart and vessels.
All these negative effects mainly concern proteins of animal origin – plant proteins are definitely safer here. As for the ketogenic diet – there are no credible scientific publications that would allow to assess its effect on the kidneys, but taking into account its principles, I would not consider it healthy in kidney disease or in preventing the development of these diseases.
Then let’s move on to stimulants – which of them harm the kidneys the most?
Maybe I’ll start with a stimulant that seems unequivocally beneficial – coffee, of course. Most large observational studies show a renal benefit from drinking this drink, in fact directly proportional to the number of cups consumed (although this benefit may not apply to one of the conditions, known as autosomal dominant polycystic kidney disease). There is no doubt about the harmfulness of cigarette smoking.
With alcohol, the matter is a bit more complicated – we can observe the so-called J-curve phenomenon: the risk of developing chronic kidney damage increases with increasing alcohol consumption, but also with approaching complete abstinence. In other words, moderate, occasional alcohol consumption is not likely to be harmful to the kidneys. However, taking into account other harmful effects of alcohol (including the unequivocal effect that promotes the formation of cancer), it does not mean that people suffering from kidney disease or those with risk factors for their development should be advised to drink alcohol.
And by the way – because this is a hot question – it is about the pharmacological effect of alcohol and therefore no special properties should be attributed to beer. If we move to the level of prohibited substances, all narcotic substances and the admixtures or contaminants they contain are very dangerous. One of the diseases well described in the scientific literature, for example, heroin nephropathy.
And what about non-steroidal anti-inflammatory drugs (NSAIDs), which Poles so eagerly reach for?
In the 70s it was a plague – NSAIDs were one of the most important groups of drugs leading to advanced renal failure. The main responsibility for this was phenacetin – a very toxic substance from this group, available in Poland in the 60s and 70s as the so-called “Tablets with a cross”. Understanding the mechanisms of action of this substance (also carcinogenic to the urinary tract) and its elimination significantly reduced the problem.
Nevertheless, it should be emphasized that each NSAID increases the risk of kidney damage in predisposed individuals and leads to the progression of existing damage. For this reason, I am very concerned about advertising this group of drugs at every commercial break on TV or radio.
In addition, their toxicity to the kidneys is strengthened by the vasoconstrictors contained in cold and flu preparations. People with chronic heart and liver diseases, people taking diuretics and dehydrated are particularly vulnerable. NSAIDs are needed and very effective in many indications, but should be warned against abuse and always taken with plenty of fluid.
We know that the kidneys are discreetly ill, which should worry us?
Swelling (not only around the ankles and lower legs, but also under the eyes or on the face), hypertension or deterioration of control of previously well-controlled hypertension (need to “strengthen” blood pressure-lowering treatment) may be eye-catching and then worrying. , foaming of urine, changes in the color of urine (including especially haematuria).
Uncharacteristic pains in the lumbar region, and sometimes pains may also appear in the course of kidney diseases (of course, you should also remember about kidney stones – renal colic is described as one of the most difficult pains to bear). Unfortunately, many of these symptoms are highly non-specific. Let me give you an example – every few months, we are visited by representatives of a profession in which it is particularly difficult to conduct self-control and a regular lifestyle. These are drivers who drive long, foreign routes. In fact, nothing is happening to them, except for gradually increasing fatigue and deteriorating well-being over the next few weeks.
Finally, they use another short stay at home for a check-up at the family doctor and … in two or three days they are already undergoing dialysis because of the so-called irreversible treatment. end-stage renal failure. Reverse, detailed analysis of their history often does not allow to identify the moment when the disease began. This illustrates the insidious, non-specific, latent history of kidney disease.
How can we diagnose abnormalities in the work of the kidneys?
If such a suspicion has already been established, which, as I said, is not easy, then the diagnosis (at least preliminary) is not difficult. It is necessary to measure the concentration of sodium, potassium and creatinine in the blood (it is also good to check LDL-cholesterol), blood count, the so-called general examination of urine (from the first or second morning sample), measurement of blood pressure and ultrasound of the abdominal cavity with an assessment of the size and appearance of the kidneys. The above tests basically identify significant kidney disease with 100% sensitivity and specificity (although, of course, to find out its cause, you still need to work a lot).
How often should we perform urinalysis and blood creatinine levels?
Precise guidelines apply only to people with diabetes and hypertension. For the sake of simplicity, it can be assumed that every diabetic patient should have blood creatinine tested and urine tested for albumin (one of the proteins that get into the urine in kidney diseases). The frequency of such tests should increase after the diagnosis of kidney damage and as the damage progresses; it happens that blood parameters are checked every 6-8 weeks.
The guidelines for the diagnosis and treatment of arterial hypertension require the determination of creatinine concentration and urinary albumin excretion as tests necessary in the diagnosis of this disease (and monitoring these parameters at least once a year in case of abnormalities). However, urine testing or creatinine are not standard tests, e.g. in occupational medicine. Therefore, they are performed too rarely. Many potent drugs can accumulate in kidney diseases (many functions of the kidneys include elimination of drugs from the body).
Therefore, the use of certain drugs requires a systematic assessment of kidney function, because their efficiency has a key impact on the dosage. For this reason, scientific societies and groups of experts in the field of cardiology, neurology, oncology and many other specialties recommend monitoring kidney function. But in healthy people such guidelines have not been formulated. The test for the kidneys is pregnancy – a condition that presents particular challenges to the kidneys of a pregnant woman. Simply put, it can be said that an uncomplicated pregnancy is a certificate of health for the kidneys – in clinically significant kidney disease, the correct course of pregnancy is practically impossible.
What is the risk of kidney disease?
The most obvious consequence is the need to start dialysis treatment. They are taken when the kidneys are unable to cleanse the body of toxic products of metabolism at all. It is important to note that this is not necessarily related to a decrease in urine volume – many patients continue to urinate, but the urine is “watery”, diluted – no toxins.
Dialysis is cleansing the body of toxins through a special filter (dialyzer, artificial kidney), which has to be done 3 times a week, and the procedure lasts 4 – 4,5 hours. We do our best to report patients at this stage of kidney damage for kidney transplantation. You can also become a candidate for transplant before starting dialysis. Unfortunately, only some of the patients will have kidneys for transplantation.
Kidney diseases also shorten life: their impaired function is a powerful risk factor for the development of cardiovascular disease, stroke, and resistant hypertension. If – as I said at the beginning of our conversation – we add diabetes, which is present in most patients, to kidney disease, then a tandem is created that poses a huge threat. Nephrologists say their patients have kidney disease but die of heart disease …
What rules should everyone who wants to have healthy kidneys follow?
I often hear this question and answer as follows: there are no rules for preventing kidney disease, because the kidneys never get sick separately. “In a healthy body, a healthy mind” – to paraphrase this saying, it should be said that “in a healthy body, healthy kidneys”. I would rather say about universal prevention of civilization diseases: together we prevent diabetes, hypertension, heart disease, cancer and kidney diseases (but also diseases of the lungs, liver, motor system, etc.).
Organs are closely related in physiology and health, but also in pathology and disease. Of course, smoking is much more important to lung disease prevention than it does to your kidneys, but it’s just a matter of emphasis. By the way – few people know that smoking is one of the most important factors in the development of bladder cancer.
So you see how it is all inextricably intertwined. One of the most serious consequences of advanced kidney disease, for example, is progressive and very severe damage to… bones. So, the four most important commandments for World Kidney Day: a healthy diet, exercise, avoid obesity, and control blood pressure.
Finally, I would like to ask you how do you assess the awareness of Poles in the field of kidney disease prophylaxis?
Not the best. I think that probably only kidney transplantation is something that evokes associations in the majority of society. The kidneys usually do not hurt, they do not give characteristic symptoms when they are ill. They are quiet and modest. Hidden deeply, they filter hectoliters of plasma every day to produce 1,5 – 2 liters of this important and underestimated fluid, thanks to which we detoxify our body so effectively. Because of this urine, they are also a bit … embarrassing. We love with our heart, it rings like a bell, it is brave and brave, but without healthy kidneys, nothing works as it should. Therefore, let us not skip the opportunity to talk about them.