December 13, 2024

Obesity linked to more rapid kidney disease progression, but may have some protective benefits too

A new study explores the relationship between obesity and chronic kidney disease (CKD), highlighting obesity’s underlying socioeconomic influences, its impact on kidney disease progression, and—surprisingly—its possible protective health benefits in the advanced stages of kidney disease.  

Obesity has a major impact on health, particularly for those with CKD. To explore this relationship in more detail, Gurleen Sahi and colleagues analyzed the linked hospital, administrative, and laboratory data of more than 198,000 kidney patients in Ontario with a particular focus on those with a body mass index above 30, which is a commonly used measurement for obesity.  

The results show that people with obesity and more advanced kidney disease were more likely to have multiple diseases, tended to have lower incomes, and used more health care than those with more preserved kidney function. The results also show that people with obesity and moderate kidney disease (stage G3 or G4) were more likely to experience faster kidney disease progression than people with lower BMIs.  

Interestingly, the data suggests that obesity may offer some health benefits as patients approach the advanced stages of kidney disease, where obesity was associated with a reduced risk of death and better transplant outcomes. The researchers note that, while the reasons behind these protective benefits cannot be exactly known, high BMI can be associated with better nutrition, muscle mass, and hemoglobin levels—all of which are often compromised in patients with advanced kidney disease—and could potentially explain the association between obesity and increased survival. The more successful transplant outcomes observed in people with obesity in this study may be in part due to more strict vetting criteria for this population, the authors speculate. They emphasize the need for more studies to explore this phenomenon.