Obesity, CKD, and population-level health

The growing burden of obesity and its impact on chronic kidney disease (CKD) was the focus of a presentation by Prof Francis Finucane, Consultant Endocrinologist, University Hospital Galway, at the Irish Nephrology Society Annual Scientific Meeting 2026.

Opening his address, Prof Finucane highlighted the dramatic rise in obesity prevalence in Ireland, and internationally, and described a “population-wide shift in BMI [body mass index]” to the right. While obesity is an important risk factor for CKD, he noted significant heterogeneity in disease development, with many individuals never progressing to CKD despite long-standing obesity.

Prof Finucane told delegates that obesity management requires the same strategic thinking applied to other major public health crises.

He cited “the single most important blueprint” for tackling population health challenges – the landmark paper, ‘Sick individuals and sick populations’ by British epidemiologist Prof Geoffrey Rose.

The framework advocates a “two-pronged approach”, the first being a whole-population strategy addressing the environmental drivers of obesity through interventions like expanded cycling lanes, sugar taxes, and restrictions on unhealthy food advertising. “These are crucially important,” Prof Finucane said.

“It’s important we don’t lose sight of the need for population-level strategy, better legislation, and better-informed politicians.” The second part focuses on identifying high-risk individuals and providing “intensive interventions” like bariatric surgery, which he described as “by far the most effective treatment for severe and complicated obesity”.

Reviewing data from TILDA [The Irish Longitudinal Study on Ageing], Prof Finucane noted that 36 per cent of Irish adults aged over 50 years have a BMI greater than 30kg/m², and one in six adults over 50 has CKD stage 3 or higher, with prevalence increasing among older people and those with obesity. He reviewed the complex relationship between obesity and kidney disease, referencing an article based on the KDIGO [Kidney Disease: Improving Global Outcomes] consensus conference in October 2024.

This paper provided “an elegant description of the complex mechanistic basis and pathology linking obesity and CKD”.

Obesity increases the risk of major CKD drivers, including hypertension and type 2 diabetes, he said. Shared pathological mechanisms include insulin resistance, chronic inflammation within adipose tissue, increased production of angiotensin-converting enzyme 2, and tumour necrosis factor-alpha. Fat accumulation within the kidney itself can also contribute to renal injury through both macroscopic and microscopic effects. At a molecular level, Prof Finucane discussed adipocyte dysfunction, including excess leptin production, reduced adiponectin secretion, and impaired suppression of the renin-angiotensin-aldosterone system.

“I think it has less to do with the volume or mass of adipose tissue and more to do with adipose tissue dysfunction. Adipose tissue is a professional fuel storage depot, and when fat is stored in the right place it is metabolically relatively benign. It’s when fat accumulates in other tissues like the pancreas that we see problems.”

Turning to treatment, Prof Finucane discussed structured lifestyle interventions in relation to obesity management. He highlighted the value of community-based programmes, such as those delivered by the west of Ireland heart and stroke charity Croí, which address weight management as a comprehensive cardiovascular and metabolic risk reduction strategy. Although successful in terms of engagement, average weight loss among programme completers is modest.

Prof Finucane then described the discovery of incretin-based therapies as “really exciting”, and “game-changing”, moving on to discuss the benefits of glucagon-like peptide-1 (GLP-1) receptor agonists.

“The most important question I ask any patient before I start these drugs is: ‘Do you think you eat too much?’ because these drugs are designed to make you eat less,” he said.

Delegates received an overview of the latest major clinical investigations like the STEP trial, which demonstrated “extraordinary results that absolutely change the therapeutic face of treatment” in people with overweight or obesity. Prof Finucane also detailed the available diabetes and cardiovascular trial outcomes that have “strengthened the case for GLP-1 therapies”, like SUSTAIN-6, SELECT, and LEADER. He then presented data from the only trial of GLP-1s with primary kidney outcomes – the FLOW trial. This illustrated that semaglutide significantly slows the progression of CKD and improves cardiovascular outcomes. Renal outcomes are frequently overlooked in obesity studies, and more work is needed to better characterise kidney-related benefits of treatment, the conference heard.

Addressing current challenges, Prof Finucane emphasised “the significant heterogeneity in response” to GLP-1 drugs, with approximately one in six patients failing to lose weight after one year of treatment. He also argued that affordability remains a major barrier to maximising the public health benefits of these therapies.

Drawing comparisons with historical examples, he said, “we need to be more like MERCK,” referring to the pharmaceutical company’s 1987 provision of millions of doses of ivermectin to combat onchocerciasis (river blindness) in Africa.

He also highlighted Volvo, which in 1959 made its patent for the three-point seatbelt freely available to competing car manufacturers, a move credited with saving millions of lives worldwide. Prof Finucane concluded that companies developing incretin therapies should take a similar approach.