Why routine kidney screening in primary care is a clinical and financial necessity

Chronic kidney disease (CKD) rarely announces itself, but it shows up clearly on the balance sheet.

Treating a patient with early-stage CKD costs a health system roughly $3,000 a year. If that same patient progresses to kidney failure, dialysis alone can exceed $57,000 annually, before counting hospitalizations, lost productivity or caregiver burden. And because kidney disease is closely tied to heart disease, diabetes and obesity, those costs rarely stay contained to a single diagnosis. That connection is the idea behind cardiovascular-kidney-metabolic syndrome (CKM), a framework that treats these conditions as one linked disease process. Nearly 90% of U.S. adults have at least one CKM risk factor, yet most people with CKD don't know they have it. For primary care, that gap is both a clinical opportunity and a financial one. Below, I outline where current screening falls short and how practices of every size can close it.

What is CKM disease, and how many people does it affect in the United States and globally?

CKM is the framework the American Heart Association (AHA) introduced in its 2023 presidential advisory to describe how heart disease, CKD and metabolic conditions such as diabetes and obesity actually behave in the body. Rather than treating those as three separate diagnoses, CKM stages a patient's risk from 0 (no risk factors) through 4 (established cardiovascular disease, often with kidney failure), because damage in one system consistently drives damage in the others.

The scale is larger than most physicians realize. In the United States, the AHA estimates that nearly 90% of adults have at least one CKM risk factor, and more than 89 million adults are already beyond stage 0. CKD alone affects roughly 14% of U.S. adults, or an estimated 37 million people, and the great majority don't know they have it. That's largely because kidney function can decline substantially before a patient feels any different, and the urine test that catches early-stage disease isn't part of a standard checkup the way blood pressure or cholesterol screening is, so the disease has room to progress quietly for years before anything prompts a physician to look for it.

Globally, nearly 800 million adults worldwide live with CKD, more than double the 378 million recorded in 1990, with a global age-standardized prevalence of approximately 14%.

What's most worrisome isn't the size of that number, but the trajectory behind it. CKD is becoming a more significant cause of death and a bigger driver of cardiovascular mortality specifically, even as kidney treatments have genuinely advanced. It is clear that the gap holding back better outcomes isn't the science. It's screening and implementation, meaning the more effective treatments we now have for slowing CKD still aren't reaching most of the people who'd benefit from them.

How is CKM disease currently diagnosed, and what limitations in that approach are keeping screening from becoming a routine part of primary care?

The two tests that do most of the work in diagnosing CKD risk are estimated glomerular filtration rate (eGFR), drawn from a basic metabolic panel, and urine albumin-to-creatinine ratio (UACR). These, paired with blood pressure levels, glucose levels and lipid panels, cover most of what's needed to stage a patient's CKM risk. Each test catches things the other can miss, which is why pairing them matters. The 2024 Kidney Disease: Improving Global Outcomes clinical practice guideline reinforces this approach, recommending that people at risk for chronic kidney disease be assessed using both GFR and urine albumin measurements to improve detection and support more accurate risk classification.

In a Carna Health screening program across 16 sites in Cameroon, we found that among participants who received both tests, blood testing alone would have missed 85% of the kidney disease cases that urine testing caught. Ordering eGFR without UACR, which is still common during routine visits, leaves a physician with a partial view of a patient's actual kidney status.

Part of the inconsistency traces back to the absence of current guidance. The U.S. Preventive Services Task Force is currently reviewing the evidence and updating its recommendations on CKD screening, as the previous evidence review and recommendation was issued in 2012 and is based on outdated information. In that gap, primary care clinicians are largely left to build their own approach to when and how to screen, and that inconsistency is where patients get missed.

Reimbursement compounds the problem. Most medical codes are built around larger interventions, dialysis, transplantation, and the care that surrounds them, rather than the preventive testing that could keep a patient from reaching that point. Until the incentive structure rewards catching CKD early as clearly as it rewards treating it late, screening will keep competing for attention in a patient visit that already has plenty of other priorities.

Why do kidney issues so often go undetected until the disease has significantly progressed, and what does that mean for treatment and cost?

Kidney disease often progresses silently, since function can decline substantially before a patient feels anything alarming, so without proactive testing, most people simply don't know there's a problem until it has advanced.

That awareness gap shows up clearly in our own screening data. In Bermuda, about 49% of participants had abnormal results, and 94% of those had no idea they had the condition. In a separate, larger initiative in Cameroon, nearly half of the nearly 35,000 people screened had abnormal UACR results, and nearly 1,000 individuals had disease severe enough to need immediate nephrology referral. That referral is no small ask in a country where specialist care is hard to come by, and most patients face an hours-long trip just to reach one, a challenge that mirrors what rural communities in the U.S. face when their nearest specialist is a large hospital or clinic hours away.

As noted above, late detection changes the entire cost trajectory of care, and the expense of managing CKD climbs steeply once a patient moves from early-stage disease to kidney failure.

These costs strain health systems and patients alike, and for those who can't afford care or lack access to specialists and dialysis, the outcomes are often bleak. CKD is now the ninth-leading cause of death globally, claiming close to 1.5 million lives a year, largely because so much of that burden is identified only once intervention options have narrowed.

With specialist wait times growing, what role can primary care physicians play in managing CKM disease and coordinating with specialists to improve outcomes before a referral becomes necessary?

Nephrology is one of the more strained specialties in American medicine right now. The Association of American Medical Colleges has projected a shortage of up to 77,100 specialists nationally by 2034, and nephrology fellowship programs have struggled for years to fill their available slots. That shortage is already showing up in referral patterns, with one study of an academic health system finding that only 45.4% of patients with an eGFR under 30 (a level guidelines say should trigger nephrology referral) who were actively seeing a primary care physician were actually referred.

That reality puts more of the CKM management burden on primary care by necessity, not by design. Blood pressure control, glycemic management, and the growing set of kidney-protective medications (RAAS inhibitors, SGLT2 inhibitors, and now GLP-1 receptor agonists in the right patients) are all things a primary care physician can manage directly for early- and moderate-stage disease. Reserving nephrology referral for advanced disease or genuinely complex cases, rather than every abnormal laboratory value, is both more realistic given specialist capacity and, done well, better for the patient, since it keeps care with the physician who already knows their full history.

This is exactly the kind of decision Carna Health's platform is built to support, giving primary care physicians the confidence to make that referral call at the right time, not too early and not too late.

How do tracking and monitoring tools help physicians understand how CKM disease progresses, and what does investing in this technology early mean for short-term and long-term patient outcomes?

A single laboratory result is a snapshot. What actually tells a physician whether a patient is stable, improving, or heading toward kidney failure is the trend across repeated eGFR and UACR measurements over time. Tools that track that trajectory, and flag when it's bending in the wrong direction, let a physician intervene while the disease is still modifiable rather than after a threshold toward reactive intervention has already been crossed.

In the near term, that kind of monitoring means fewer unnecessary specialist referrals, because a physician can distinguish between a patient whose numbers are drifting slowly and one whose kidney function is dropping quickly enough to need urgent attention. In the longer term, the value compounds as slowing progression by even a modest amount can be the difference between a patient managing their condition in a primary care setting for a decade or more, and that same patient reaching dialysis. The experience in Bermuda is a useful example, as the screening data was compelling enough that it led directly to the country's Ministry of Health establishing a nationwide CKD Integrated Care Pathway, essentially building coordinated follow-up infrastructure around what the tracking data showed.

There have been discussions around the use of GLP-1s in kidney care. What does the current evidence show about their effect on kidney function, and how should physicians factor that into patient conversations?

GLP-1 receptor agonists were originally developed for glycemic control, but the evidence has moved quickly, and data over the past decade have consistently shown cardiorenal benefits that go beyond blood sugar and weight, particularly in high-risk patients with type 2 diabetes. The clearest kidney-specific evidence comes from the FLOW trial, which tested semaglutide in more than 3,500 patients with Type 2 diabetes and existing CKD. The trial was stopped early for efficacy. Semaglutide reduced the primary composite outcome of major kidney events, cardiovascular death, and death from any cause by 24%, and it slowed the rate of eGFR decline over time compared with placebo.

That kidney-specific signal builds on a broader pattern across GLP-1 therapeutics. A study by the University Medical Center Groningen, in the Netherlands, found that for people with obesity but without diabetes, semaglutide at a higher dose has reduced body weight by up to 15% and lowered the risk of major cardiovascular events by 20%. A new generation of multihormone agents, such as tirzepatide, which combines GLP-1 and glucose-dependent insulinotropic polypeptide receptor activity, is showing even stronger metabolic and weight-loss results, with up to 22.5% weight loss in phase 3 trials. Across this drug class, the trend points toward metabolic therapies carrying measurable organ-protective effects, kidneys included, rather than glucose control being the only benefit.

For physicians, the practical implication is that a GLP-1 prescribing decision for a patient with Type 2 diabetes and early kidney impairment isn't purely a diabetes management choice anymore. The kidney benefit is now backed by a dedicated outcomes trial, a meaningfully higher bar of evidence than the general cardiometabolic data these drugs were first known for. That said, physicians should be precise about what the evidence covers. FLOW enrolled patients who already had Type 2 diabetes and a defined degree of existing kidney disease. It doesn't yet tell us how GLP-1s perform in patients with CKD but without diabetes, and the newer combination agents haven't been through the same dedicated kidney-outcomes testing that semaglutide has. For a patient with both diabetes and CKD, kidney protection is now a real, evidence-backed reason to consider the therapy. For other populations, it's still worth raising, but it should be framed as promising rather than proven.

How can AI-powered diagnostics support primary care physicians, who may not have specialized training in kidney or metabolic disease, in identifying at-risk patients earlier?

Primary care physicians aren't given the granular training to manage kidney and metabolic disease the way a nephrologist or endocrinologist is, which is why specialists exist. But that division of labor assumes a patient can actually reach a specialist, and for many, especially in rural or underserved areas, that access isn't there.

AI-powered diagnostics can help close that gap. Point-of-care testing paired with AI-driven risk stratification turns a patient's results into a clear signal: Monitor closely, refer now, or recheck later. The physician doesn't have to interpret subtle kidney-specific markers themselves.

That support matters in two ways. For patients without reasonable access to a specialist, it means their risk still gets managed rather than going untracked. For patients who might eventually need one, it means catching risk factors early enough that some never progress that far. We've seen this in our own global screening programs, where community health workers, not nephrologists, used point-of-care testing with AI-driven interpretation and still caught high rates of disease needing follow-up. A tool that works in the hands of a community health worker with no clinical background will work at least as well for a primary care physician who already brings years of medical training, just not in this particular specialty.

How should health systems, from large networks to small and medium independent practices, weigh the cost of investing in earlier screening and technology against the cost of treating advanced kidney and metabolic disease?

The math looks different depending on where a system sits, since CKD costs don't rise in a straight line. One U.S. claims analysis found annual costs for a commercially insured patient jump from roughly $7,500 with no kidney disease to nearly $77,000 at stage 4 or 5. Early detection saves more than a single expensive treatment. It prevents years of compounding costs most systems don't see coming.

Large networks are better positioned to act on that now, largely because they're more likely to sit inside value-based or kidney-focused payment models, including Medicare programs built to reward earlier detection. That gives them a way to see the financial upside within their own contracts.

Independent and mid-sized practices rarely have that leverage, and building the data infrastructure to justify screening on their own isn't realistic at their scale. What tends to work instead is point-of-care tools that don't require new specialist hires, often paired with a hospital system or public health partnership that helps cover the upfront cost. The case for early detection holds everywhere. What changes by size is whether a system reaches it through its own contracts or through outside support that makes the technology affordable.

Salvatore Viscomi, M.D., is the co-founder and CEO of Carna Health, a global digital health company transforming the prevention and management of cardio-kidney-metabolic disease through artificial intelligence-powered diagnostics, predictive analytics, and large-scale population screening. A physician-entrepreneur, he has over 20 years of patient-facing experience.