French Kidney Transplants: A 12-Year Deep Dive into Treatment Patterns

Hey everyone! So, I was looking at this really interesting study called OISTER, and guess what? It gives us a fantastic peek into how kidney transplant patients in France have been cared for over a whopping 12 years, from 2009 right through to 2020. It’s all based on data from the French national healthcare database, which covers pretty much everyone in France – how cool is that for getting a real-world picture?

The main gig here was to see what kind of immunosuppressive treatments these patients were getting and how well they were doing in terms of survival – both the patients themselves and the transplanted kidneys (the grafts). Because, let’s be real, preventing the body from rejecting that new kidney is absolutely key, and it needs lifelong treatment.

What We Looked At

The OISTER study is what you call a retrospective cohort study. Basically, they looked back at data for all adult patients who got a kidney transplant in France during that 2009-2020 window. They followed each patient from the day of their transplant until the study ended, they passed away, or their new kidney stopped working. The database is super detailed, documenting every single immunosuppressive drug delivery from pharmacies.

We’re talking about a massive group here: 34,600 patients were eligible for the study. The median time they were followed was 4 years, but some were tracked for up to 7 years or even longer. That’s a solid chunk of time to see what’s really happening.

The Big Picture: Survival

Okay, let’s get to the good news first. The survival rates look pretty high! At the five-year mark after transplantation:

• Overall patient survival probability was 89.0%.
• Death-censored graft survival (meaning the kidney was still working, even if the patient passed away from something else) was 85.0%.

This is actually quite encouraging and seems consistent with, or even slightly better than, what’s been reported in other international studies, even though patients are getting older and often have other health issues.

Interestingly, patient survival *did* depend on age – younger folks had a higher chance of being alive at five years compared to older patients. But here’s a neat finding: graft survival was pretty similar across all age groups of recipients. So, the kidney itself seems to do well regardless of whether the recipient is 20 or 70!

The Treatment Landscape

Now, onto the main event: the immunosuppressive treatments. The study documented treatment for over 92% of the patients, which is great coverage. The patterns they saw align pretty well with the standard recommendations out there, like those from the European Association of Urology.

The absolute backbone of treatment was (and still is!) a class of drugs called calcineurin inhibitors (CNIs). About 91.3% of patients received one. Within this group, tacrolimus was the clear favourite, becoming even more popular over the decade, while ciclosporin saw its use decline.

Next up were antimetabolites, used by about 90.5% of patients. These are almost always used alongside a CNI. And then there were corticosteroids, used by 88.1%, though their use also decreased over the study period.

Shifting Sands? Newer Therapies Enter the Scene

While the core combination remained dominant, the study saw some shifts and the introduction of newer players:

• mTOR inhibitors (mTORi): Used by 16.1% of patients. The big change here was that everolimus pretty much took over from sirolimus as the go-to mTORi by the end of the decade. These were often added to a CNI regimen or used after a switch.
• Belatacept: Used by 3.9% of patients. This is a newer type of drug that’s been around in the EU since 2011. Its use increased over the study period, but it was still used in a relatively small number of patients compared to CNIs.

The standard approach usually starts with a CNI, an antimetabolite, and corticosteroids. If patients have issues with CNIs (which can happen, like kidney toxicity), doctors might switch them to something else. The study showed that about a quarter of patients (23.5%) did switch their treatment at some point, and some even switched more than once. mTOR inhibitors and other CNIs were the most frequent treatments patients switched *to*, with belatacept also being an option after a switch.

What’s really striking is how stable the overall patterns were. Despite the minor shifts in specific drugs (like tacrolimus replacing ciclosporin, or everolimus replacing sirolimus), the core strategy remained consistent. And get this – 76.5% of patients stayed on their initial immunosuppressive treatment throughout the entire follow-up period! That tells us that for most people, the initial plan works well for a long time.

Why This Matters and What’s Next

This study is a big deal because it gives us a really comprehensive, real-world look at post-transplant care across an entire country over a long period. It confirms that the standard treatment approaches recommended in guidelines are indeed what’s happening in practice in France, and that these strategies are associated with high survival rates.

It also highlights the increasing use of newer options like everolimus and belatacept, even if they are primarily used after a switch from the initial regimen. Belatacept, in particular, is interesting because it might have fewer side effects like high blood pressure or diabetes compared to ciclosporin.

The study points out that identifying belatacept use was a bit tricky for most of the study period because it was mainly given in hospitals, and the database doesn’t detail individual drugs given in hospital pharmacies until recently (July 2020), when a “retrocession” procedure made it available via community pharmacies. They had to use a clever algorithm to estimate its use before then. This change in 2020, making belatacept easier to access outside of the hospital, could potentially lead to more doctors prescribing it in the future, maybe even influencing costs. It’ll be fascinating to see if future studies show an increase in belatacept use because of this.

A Few Puzzles Remain

Like any study looking back at data, this one has its limits. The biggest one? We don’t know *why* doctors decided to change a patient’s treatment. Was it a side effect? Was it the patient’s kidney function? Was it a viral infection? The database just shows *what* happened, not the clinical reasoning behind it.

Also, the database only goes back to 2008, so if a patient had a kidney transplant *before* that and then got another one during the study period, the study might not fully capture their complete transplant history.

Despite these limitations, the OISTER study provides invaluable insights. It shows a picture of stable, guideline-aligned immunosuppressive care in France over a decade, associated with excellent patient and graft survival outcomes. It sets the stage for future studies to see how newer therapies and changes in access might further shape post-transplant care.

Source: Springer