- Scientists know that depression accelerates the progression of chronic kidney disease (CKD), but little research discusses how depression affects kidney function in the general population.
- A Chinese university recently discovered a strong correlation between high depressive symptoms and a 39% greater chance of rapid kidney decline in individuals with normal kidney function.
- These findings suggest the need for mental health screening and interventions to reduce the risk of developing CKD.
Kidney specialists have long observed that individuals with CKD commonly experience depression.
Until now, though, researchers had not explored whether depression could increase the risk of renal dysfunction in otherwise healthy individuals.
In a recent study of adults with healthy kidneys, the researchers found that those with major depression were more prone to develop a faster-than-normal deterioration in kidney function. The results appear in the Clinical Journal of the American Society of Nephrology (CJASN).
The lead author, Dr. Xianhui Qin of Southern Medical University in China, explains: “CKD is a leading risk factor for cardiovascular disease, kidney failure, and mortality worldwide. Therefore, the identification of more modifiable risk factors may reduce the huge burden of CKD and its related complications by leading to early detection and prevention.”
Dr. Qin and the study’s co-authors analyzed data on adults participating in the China Health and Retirement Longitudinal Study (CHARLS), a national study of China’s middle-aged and elderly population.
The team gathered complete measurements from 4,763 individuals aged 45 years and older with healthy kidneys. The mean age was 59, and males made up 45% of the study population.
The researchers analyzed data from 2011, 2013, and 2015 and conducted one-to-one interviews and follow-ups.
During each 2-yearly follow-up, doctors performed physical measurements, and they collected blood samples every two follow-up cycles.
The researchers measured kidney function using the estimated glomerular filtration rate (eGFR). They assessed depressive symptoms with a 10-item Center for Epidemiologic Studies Depression (CES-D) scale.
During an average follow-up of 4 years, 260 or 6% of the participants experienced accelerated kidney dysfunction.
After adjusting for demographic, psychosocial, or clinical factors, the team found a “significant positive association between baseline depressive symptoms and rapid decline in kidney function” in the general population.
Specifically, they found that individuals with “high depressive symptoms” had a 39% greater risk of “rapid decline in kidney function.”
Depression is a common mental health disorder, which is prevalent in people with CKD. It may activate several “potential mechanisms” that could contribute to the rapid deterioration of kidney function.
According to a paper in World Psychiatry, the first possible culprit — increased inflammation — occurs in 25–50%Trusted Source of people with depression.
According to the new study’s authors, results from previous research have shown that people with major depression have higher levels of circulating inflammatory proteins called cytokines. These cytokines may trigger autoimmune processes that lead to dysfunction of the endothelium, which is the layer of cells that line blood vessels. It might also trigger kidney fibrosis, which leads to kidney disease.
The study authors also suggest that health-related behaviors, such as poor nutrition, reduced social interaction, physical inactivity, and not seeking medical care, may also impair kidney function.
The scientists found that participants with the highest depressive symptoms consistently had not had access to many educational opportunities and, consequently, may have less emotional resilience or awareness of how to take good care of themselves.
Wu is an American-born Chinese two-time kidney transplant recipient. Living with CKD from early childhood, she could not discuss her condition or the emotional turmoil resulting from her illness and surgeries. She relates:
“The findings of the article do not surprise me: when people are depressed, they are not as motivated to care for themselves. […] Mental health services need to be available when a person is in decline, not just in the final stages of kidney disease.”
The study’s authors admit to several limitations. For instance, the study identified an association with but cannot prove that depressive symptoms cause kidney disease.
Also, the researchers only gauged kidney function at the baseline and final visits, but more frequent assays would have allowed a more precise assessment.
The authors also note that they did not measure urine protein or urine albumin levels. These factors could have influenced the links between depressive symptoms and kidney decline.
The authors hope that their findings will help in the development of depressive symptom screening. In turn, this may lead to “effective psychosocial intervention[s] to improve primary prevention of CKD.”
Wu also hopes that further research will engender solutions for people dealing with depression and CKD. She recommends: “I would highly hope and suggest the study is expanded to the Asian population in the United States, and to teenagers and young adult transplant recipients who have been shown to experience depression. It would also be helpful for the investigators to explore and include anxiety with depression because these are very common challenges that those with kidney failure, and even a chronic illness, experience.”