Fluctuations – known as the ‘yo-yo’ effect – in body mass index (BMI) and blood pressure are associated with the progression of diabetic kidney disease in people with type 1 diabetes, new papers have revealed.
The findings, shown in two studies from Dr Murat Ozdede, Visiting Research Fellow, and Janaka Karalliedde, Professor of Diabetes, both from King’s College London, indicate that only having good average blood pressure and weight may not be enough to prevent progression of the disease. Instead, keeping fluctuations under control may be a better way to keep the kidneys healthy.
Variability – also known as ‘yo-yo-ing’ – in weight and blood pressure has been shown to be harmful in people with type 2 diabetes with regard risk heart and kidney disease. Our work is the first demonstration of this potential risk in people with type 1 diabetes, many of whom had normal weight, BMI and blood pressure. Future studies will need to explore if reducing variability with treatments can reduce the risk of kidney disease.”
Janaka Karalliedde, Professor of Diabetes, King’s College London
Diabetic Kidney Disease (DKD) affects up to 40% of people with diabetes and is one of the leading causes of kidney failure in the UK and many countries around the world. Individuals with kidney failure require kidney replacement therapy. Doctors already know that DKD is linked to higher blood glucose, higher blood pressure and protein in the urine. However, these biological functions change over time. Therefore, the researchers were interested in exploring whether variation of these risk factors may affect the body in ways that stress the kidneys and contribute to progression of kidney disease.
The first study looked at changes in systolic blood pressure (max pressure) and diastolic blood pressure (when the heart rests in between beats). The researchers measured variation in visit-to-visit changes, taken from test results of 3,079 adults with type 1 diabetes between 2004 and 2018.
They used estimated glomerular filtration rate (eGFR) test results to understand how well the kidneys were filtering the blood. A 50% fall of eGFR, or a final eGFR below 30 – indicating serious kidney damage – were the primary endpoints.
They found that both a higher systolic blood pressure and diastolic blood pressure variability was linked to substantially higher risk of kidney decline. This was independent of average blood pressure, meaning two people could have the same average systolic blood pressure, but the one who has higher variability may be at greater risk of kidney harm.
The second study explored whether BMI fluctuation – also known as metabolic cycling – could add additional stress to the kidneys and lead to the progression of the disease.
The researchers studied 3,270 adults over roughly 9.6 years, taking at least six BMI measurements during that time. They used four different ways of measuring variability to confirm their analyses.
They found that one of the key factors contributing to worsening of the disease was higher BMI variability, even after adjusting for other risk factors. After 12 years, cumulative incidence of the kidney endpoint was 11.9% in the highest variability group, compared with just 2.1% in the most stable group.
Baseline BMI itself was fairly similar between the different groups, suggesting that simply ‘being heavier’ was less of a risk factor than BMI that changed over time.
These findings are of particular importance considering recent trends in weight loss diets and medication, that can cause sudden weight loss caused by weight gain – a phenomenon known as the ‘yo-yo’ effect.
Rapid fluctuations in weight or blood pressure can cause damage to the blood vessels in the kidney. People with diabetes are more susceptible to blood vessel damage and it’s vital to prevent further aggravating factors. Avoiding fluctuations in weight, blood pressure, and blood sugar levels may help reduce to risk of kidney damage.”
Janaka Karalliedde, Professor of Diabetes, King’s College London
Source: King’s College London
