Focusing on avoiding weight gain and maintaining physical fitness may be more beneficial than typical weight loss techniques, researchers in a new study published in Obesity said.

In the study, researchers call into question the established strategy for chronic kidney disease (CKD) prevention in obese people.

The findings call into question the usual approach to preventing chronic kidney disease (CKD) in obese people. They propose that rather than focusing solely on weight loss, limiting weight gain and maintaining physical fitness may be more useful in lowering CKD risk.

While the well-established association between obesity and CKD remains undisputed, this study offers a new perspective, claiming that maintaining a healthy weight and engaging in physical exercise may be as important as losing excess pounds in the fight against CKD. This is a serious worldwide health issue, and these findings may open the door for novel prevention strategies.

Researchers evaluated 1208 obese patients recruited in the National Institutes of Health's (NIH)-sponsored Multi-Ethnic Study of Atherosclerosis (MESA) in a large study spanning six US states. The individuals had no history of diabetes, heart disease, or kidney disease and were followed up at 18 months, 3 years, and 5 years. Unlike previous research on physical exercise and kidney risk, this NIH-funded study focuses on weight gain.

The researchers discovered a relationship between weight gain and the risk of chronic kidney disease (CKD). The risk of CKD increased by 1.34% for every 5kg increase in weight from the baseline. Researchers examined cystatin C and serum creatinine levels in blood tests to measure CKD risk, allowing them to calculate the estimated glomerular filtration rate (eGFR). Elevated eGFR levels have been linked to an increased risk of CKD.

The study revealed an unexpected finding in terms of slow walking pace was related to a considerable increase in the risk of renal impairment, regardless of hypertension history. This emphasises the need for physical activity to sustain kidney health.

According to available data, chronic kidney disease affects about 3.6 million people in the United States, making it a major public health concern.

Disturbingly, CKD-related mortality in the country increased from 91.7 per 1,000 people in 2019 to 100.6 per 1,000 people in 2020, thereby underlining the importance of further study in this field.

According to a 2022 study published in Kidney Supplement, CKD affects more than 10% of the global population or more than 800 million individuals.

The researchers noted in their paper that it is more common in elderly people, women, racial minorities, and people with diabetes and hypertension.

The disease has a significant impact on low- and middle-income countries, which are the least prepared to deal with its effects.

They further noted that notably, it has become one of the major causes of worldwide mortality and is one of the few noncommunicable diseases that has seen an increase in associated deaths over the last two decades. Given its extensive impact, there is an urgent need for increased preventative and treatment measures.

Dr Meera N. Harhay, Department of Medicine, Drexel University, said that in adults, obesity is linked with a high risk of CKD. However, researchers did not observe any relationship between low kidney disease risk and weight loss. Despite this, weight loss still has benefits like glycemic control or blood pressure control.

Pointing out the research, she noted that there is limited research related to the precise mechanisms that are associated with weight loss and renal impairment.

 “We already know that obesity raises the risk of type 2 diabetes, a condition that is the main driver of chronic kidney disease in our country. However, when we focused on adults with obesity who did not have diabetes or kidney disease at baseline, we found that it was weight gain and low physical fitness that were risk factors for CKD, whereas weight loss was not necessarily protective,” Dr Harhay said.

"The improved glycemic and blood pressure control that we typically see with weight loss might be more consequential in a population that already has chronic kidney disease or in adults with severe obesity who could not qualify for MESA if they weighed more than 300 pounds,” she further added.

pointing out that fitness may be a major factor in predicting the risk of CKD in individuals with obesity, she emphasized the need for further research to determine if the findings from this research are valid when evaluating interventions to prevent weight gain and improve physical fitness.