On 22nd May, The Lancet published a study titled “Factors affecting outcomes in patients reaching end-stage kidney disease worldwide: differences in access to renal replacement therapy, modality use, and hemodialysis practices”.
Factors like in-home hemodialysis, in-center hemodialysis, renal replacement therapy, the duration of dialysis and the frequency of dialysis were calculated in different countries. It was found that at some places in the world in-home hemodialysis emanated a low mortality rate whereas by changing the variables and conditions in a few countries, in-center hemodialysis showed promising results. These findings were of prime importance for health policymakers.
In this study, national registries like the US Renal Data System provided data on renal treatments for patients of end-stage kidney disease to make an upright comparison.
As the title suggests, this study looked into different factors across different countries that influenced the mortality rates in patients of end-stage kidney disease. It is estimated that more than two million people suffer from end-stage kidney disease worldwide. To provide life-sustaining treatments to these patients, it is crucial to scrutinize the available treatment options and their success rates.
The study was a compilation of many international cohort studies that assessed and compared population differences in the incidence of kidney failure. The study moved on to evaluate the medical options available to patients of renal dysfunction, and what choices were preferred over others.
In this regard, the three major treatments were focused in the discussion which included in-center hemodialysis, in-home hemodialysis and renal replacement therapy (RRT). The corresponding mortality rates across countries were also presented in the study. An in-depth analysis was presented on how the national income status of a country influenced the treatment choices of patients and on the underlying disparities in the availability of treatment options.
The data was collected from about 50 national registries to compare trends in treatment options and survival rates of end-stage kidney disease patients. Analysis of the trends will help in devising interventions for improving treatment options across countries.
The study compared the incidence and prevalence of end-stage kidney disease patients. These findings are of the utmost importance in evaluating the treatment options and a nation’s overall status at combating renal diseases.
Incidence of a disease indicates the appearances of new cases of a disease while prevalence of a disease indicates the number of people in a population who are living with a particular disease.
The incidence rate of end-stage kidney disease in a country has shown a strong correlation with the Gross Domestic Product (GDP) income of a country and the GDP percentage allocated to healthcare. Firstly, it was found that in some countries, an increase in prevalence was recorded with little change in incidence. This indicated that the mortality rate in end-stage kidney disease patients has declined as the survival rate of people living with a renal disease was improved (as indicated by high prevalence). Meanwhile, the number of people who developed end-stage kidney disease showed negligible change which suggested that the used interventions were satisfactory. Nevertheless, room for improvement is still present which could assist in decreasing the incidence rate.
Another trend was observed in which the prevalence of end-stage kidney disease patients was on a decline, while the incidence of end-stage kidney disease patients increased. This particular trend was suggestive of the fact that government or a third party payment for dialysis is limited in the countries. Also, these trends were associated closely with middle to low-income countries. However, while summarizing the data from all the countries, researchers in this study found an overall upward trend in end-stage kidney disease prevalence. This finding supports the impact of improved treatment facilities for end-stage kidney disease patients who can live longer if adequate medical help is provided.
High-income countries which had access to RRT were found to have the lowest end-stage kidney disease incidence. These countries included Australia, New Zealand and European countries. These countries were also found to have alternative conservative kidney management which was popular amongst the population.
But the current data is not sufficient to link the low incidence to conservative kidney management. Surprisingly, end-stage kidney disease incidence was not low at all in high-income countries. The US and high-income Eastern and Southeastern Asian countries were found to have high end-stage kidney disease incidences. This suggested a high burden of chronic kidney diseases in populations accompanied by high risk factors for renal dysfunction that included hypertension, diabetes, obesity and glomerular diseases.
Another important trend in this context was to observe how end-stage kidney disease incidence rates have plateaued over the decade. This, as mentioned earlier, indicates improved clinical practices in treating the diseases under discussion. Regardless of whether they are due to prevention of chronic kidney diseases or slowing of the progression of diseases leading to kidney failure, the contributing factors for low or stagnant end-stage kidney disease incidences are prominent public health achievements.
As this study looked at treatment modalities, it was observed that in-home hemodialysis and kidney transplantation were preferred over in-center hemodialysis. Amongst these treatment modalities, kidney transplants showed to help improve the quality of life of patients and also helped them reach median ages that were closely comparable with people who did not have end-stage kidney disease.
In 2013, it was recorded that kidney transplantation for treating patients with end-stage kidney disease ranged from 57-72% in Nordic countries, Estonia and the Netherlands. In contrast, in some Asian and European countries, the popularity of transplantation was low and only about 10% of patients with end-stage kidney disease opted for transplantation as their treatment option.
While comparing the treatment modalities and disease incidence, it was noted that countries with low incidence rates had kidney transplantation as their preferred mode of treatment. This finding can be very useful from a public health viewpoint, as the general treatment trend and corresponding incidence rate can help in devising health policies for end-stage kidney disease across many countries.
Although kidney transplant has been a fruitful treatment option for many countries, an anomalous finding has questioned the timing of giving kidney transplantation to patients. 18-40% end-stage kidney disease patients in Denmark, Iceland, Norway, Sweden, the Netherlands and the UK were found to recommend pre-emptive kidney transplantation. This caused an increase in the incidence of end-stage kidney disease.
With the increased popularity of kidney transplantation, doctors have been seen to over-diagnose a renal condition and go directly for kidney transplantation, bypassing other options which may be more suitable in a particular case.
While making a comparison between in-home hemodialysis and in-center hemodialysis, it was found that in-home hemodialysis was preferred. The clinical outcomes were found to be poor for in-center hemodialysis, making in-home hemodialysis as the preferred option. In-home hemodialysis has become increasingly popular in many countries as it is convenient for the patient to stay in their home and get the required treatment instead of travelling to the hospital and waiting in lines for their turn.
In Hong Kong, 45% of patients, while in Colombia, New Zealand and the Jalisco region of Mexico, 23-31% of the patients with end-stage kidney disease are being treated with an in-home hemodialysis. These findings are significant as these countries are setting precedence for other countries that have not been using in-home hemodialysis as their preferred treatment option.
Considering its increased popularity, the US has increased the use of in-home hemodialysis from 8% to 10% from 2009-2010. It is also worth noting that if in-home hemodialysis becomes a preferable mode of treatment, the disease burden of in-center treatments can be reduced by 2/3 of the original influx of patients.
While the majority of countries use in-home hemodialysis, a prominent number of countries rely on in-center hemodialysis as the primary mode of treatment. Countries in Eastern and Southeastern Asia have at least 85% patients who receive treatment via an in-center hemodialysis. In this context, Japan has achieved strikingly impressive clinical outcomes by making use of in-center treatments for end-stage kidney disease patients. In Japan, hemodialysis mortality is low. This can give valuable insights into clinical practices from which other countries can improve their mortality figures.
While comparing the clinical practices of in-center hemodialysis in Japan with other countries, it was noticed that in Japan, anemia management is less intensive, erythropoietin stimulating agent doses are lower and less intravenous iron is used.
Additionally, targets for hemoglobin, serum ferritin, and parathyroid hormone are also found to be lower than used in many European countries and the USA. However, in Japan strict dialysis practices were observed with increased central dialysate composition and ultra-pure dialysate water. The use of surgical vascular access was another salient feature in the in-center dialysis practices of Japan.
A vascular access uses a surgical technique to create a vein in the circulatory system of the patient undergoing dialysis. This technique is used for an increased blood flow so that blood is purified in larger volumes without collapsing the vein due to increased pressure. This technique is classified in three types — arteriovenous fistula (AVF), atreriovenous graft and central venous catheter (CVC).
The most commonly used vascular access technique is AVF which gives most favorable outcomes. Japan and Russia are the countries where the use of AVF is most prevalent, up to 90%. The high AVF has attained crucial clinical importance since policy changes, guidelines and quality initiatives are being taken in countries with low rate of AVF use. This is being done so that the use of AVF is promoted and the population that can benefit from this is increased.
Other contributing factors like the duration of dialysis and the frequency of dialysis have also been discussed in the paper. While some countries believe that larger durations of dialysis e.g., 3 hours a day and 12 hours a week yield better results, other countries prefer going with short dialysis sessions on alternate days. Another proposed notion was to make the weekly dialysis duration of 15 hours or more. But further studies have to be done to reach a consensus between nephrologists across countries to decide on dialysis duration.
The study has brought forth many interesting facts and figures regarding clinical practices for end-stage kidney disease treatment. Except for a few limitations, like covering the data from all low-income countries and densely populated countries like China and India, the study has given an in-depth analysis on treatments for renal dysfunction.
The findings of this study can help health policymakers to incorporate clinical practices in their setups to improve clinical outcomes and survival rates in end-stage kidney disease patients worldwide.