1 of 2 | People who gained weight and had slow gait speed, indicating low physical fitness, developed kidney disease at a faster rate compared to those with stable weight and higher fitness, according to Dr. Meera N. Harhay, a professor of medicine at Drexel University College of Medicine. The study was conducted in Philadelphia. Photo courtesy of Drexel University College of Medicine
NEW YORK, Sept. 28 (UPI) — A new study suggests that maintaining physical fitness and avoiding weight gain may be more important than weight loss itself in preventing kidney disease among obese adults.
The research, published in the journal Obesity, was conducted by scientists from Drexel University’s College of Medicine and Dornsife School of Public Health in Philadelphia.
This study is one of the first to investigate the relationship between physical fitness, weight gain, and chronic kidney disease risk in an obese population without diabetes or kidney disease as a baseline. Previous studies have shown a connection between weight gain and a higher risk of chronic kidney disease.
“Over 40% of U.S. adults are obese, which independently increases the risk of kidney disease,” said lead author Dr. Meera N. Harhay in an email to UPI.
Dr. Harhay is a professor of medicine at Drexel University College of Medicine.
“Most studies examining kidney disease risk factors in obese adults have focused on those with diabetes or other risk factors like cardiovascular disease,” she explained. “However, many obese adults do not have diabetes and may be otherwise healthy.”
In contrast to previous research, the participants in this study did not have diabetes, heart disease, or reduced kidney function at the start. Chronic kidney disease affects more than 1 in 7 U.S. adults, with estimates suggesting that 9 out of 10 of these individuals are unaware of their condition.
Deaths from chronic kidney disease are increasing, particularly among Black and Hispanic populations. In 2019, the adjusted mortality rate was 91.7 per 1,000, which rose to 100.6 per 1,000 in 2020.
Furthermore, providing treatment for patients with chronic kidney disease places a significant burden on the healthcare system, with Medicare alone spending over $85 billion in 2020. Currently, there are over 88,000 individuals waiting for a kidney transplant in the United States.
The study followed 1,208 overweight and obese adults from six different cities across the country who were part of the National Institutes of Health-sponsored Multi-Ethnic Study of Atherosclerosis.
Over a median of nine years, the participants underwent follow-up exams at 18 months, three years, five years, and 10 years. The researchers discovered a link between weight gain and an increased risk of chronic kidney disease. Specifically, every 5-kilogram increase in weight from the baseline corresponded to a 1.34 times higher rate of developing the disease.
The study also examined the association between physical fitness, measured by walking pace, and kidney function. Individuals with a slower walking pace (under 2 miles per hour) demonstrated a more rapid decline in kidney function.
These findings held true regardless of whether the participants had high blood pressure at the start. Dr. Harhay stated, “We found that individuals who gained weight and those with slow gait speed, indicating low physical fitness, developed kidney disease faster than those who maintained stable weight and had higher fitness levels.”
She emphasized the importance of preventing weight gain and improving physical fitness as strategies for reducing the risk of kidney disease among obese adults. While weight loss is beneficial for many reasons, maintaining weight and improving fitness should be the focus.
The study included individuals from various racial and ethnic backgrounds, as well as different age groups, who did not have diabetes, kidney disease, or known cardiovascular disease at the start. Therefore, these results may not be applicable to adults with these risk factors or extreme obesity.
Although the study did not find a significant association between weight loss and a lower risk of chronic kidney disease, Dr. Harhay mentioned that weight loss likely has kidney-related health benefits in this population, such as improved glycemic and blood pressure control.
Dr. Reshmi Srinath, an assistant professor at Mount Sinai Health System in New York, described the study as “very reliable” and highlighted the importance of assessing the risk of developing kidney disease in addition to diabetes and cardiovascular outcomes. She emphasized the need for healthcare professionals to monitor kidney function in patients with weight gain.
Dr. Marie Nevin, an endocrinologist with Summit Health in New Jersey, praised the study’s size and 10-year duration, calling it a “solid study.” She emphasized the significance of these findings, as they suggest that individuals can positively impact their risk for kidney disease through lifestyle modifications.
However, Dr. Nevin noted that the lack of a protective effect from weight loss on kidney disease warrants confirmation in larger studies.
