Preterm and early-term birth are strong risk factors for the development of chronic kidney disease (CKD) from childhood into mid-adulthood, suggests a study from Sweden published by The BMJ on May 1, 2019.
Given the high levels of preterm birth (currently 10% in the United States and 5%-8% in Europe) and better survival into adulthood, these findings have important public health implications, say the researchers.
Preterm birth (before 37 weeks of pregnancy) interrupts kidney development and maturity during late stage pregnancy, resulting in fewer nephrons forming.
Nephrons act as the filters that remove waste and toxins from the body.
Lower nephron numbers have been associated with the development of high blood pressure and progressive kidney disease later in life, but the long-term risks for adults who were born prematurely remain unclear.
So a team led by Professor Casey Crump at the Icahn School of Medicine at Mount Sinai in New York, US, set out to investigate the relationship between preterm birth and risk of CKD from childhood into mid-adulthood.
Using nationwide birth records, they analysed data for over four million single live births in Sweden from 1973 to 2014.
Cases of CKD were then identified from nationwide hospital and clinic records through 2015 (maximum age 43 years).
Overall, 4,305 (0.1%) of participants had a diagnosis of CKD, yielding an overall incidence rate of 4.95 per 100,000 person years across all ages (0-43 years).
After taking account of other factors that might be important, they found that preterm birth (less than 37 weeks) was associated with a nearly twofold increased risk of CKD into mid-adulthood (9.24 per 100,000 person years).
Extremely preterm birth (less than 28 weeks) was associated with a threefold increased risk of CKD into mid-adulthood (13.33 per 100,000 person years).
A slightly increased risk (5.9 per 100,000 person years) was seen even among those born at early term (37-38 weeks).
The association between preterm birth and CKD was strongest up to the age of nine years, then weakened, but remained increased at ages 10-19 years and 20-43 years.
These associations affected both males and females, and did not seem to be related to shared gene-tic or environmental factors in families.
This is an observational study, and as such, can’t establish cause, and the researchers acknowledge some limitations, such as a lack of detailed clinical data to validate CKD diagnoses and potential misclassification of CKD, especially beyond childhood.
However, the large sample size and long-term follow-up prompted the researchers to conclude that preterm and early term birth “are strong risk factors for the development of CKD from childhood into mid-adulthood”.
People born prematurely “need long-term follow-up for monitoring and preventive actions to preserve renal function across the life course,” they add.
And they call for additional studies to assess these risks in later adulthood, and to further explain the underlying causes and clinical course of CKD in those born prematurely.
Are there typically early symptoms of chronic kidney disease? I was diagnosed with it last month but don’t have any symptoms. What causes this disease? Can it be genetic?
In its early stages, chronic kidney disease (CKD) rarely causes noticeable symptoms.
Although genetics may play a role in its development, CKD is most commonly the result of either diabetes or high blood pressure.
When diagnosed early, there are often steps that can minimise the damage and slow the progress of this disease.
Your kidneys are two bean-shaped organs – each about the size of a fist.
They are located in the back of your abdomen on either side of your spine.
Your kidneys’ main job is filtering waste and excess fluid from blood to make urine.
Kidneys also perform other tasks, such as adjusting the balance of minerals and acids in the blood and regulating blood pressure.
Kidney disease happens when the kidneys have been damaged and no longer work the way they should.
As in your situation, it’s common for kidney disease not to cause any obvious symptoms when it first develops.
As the disease worsens, symptoms may appear. But they are often vague and can include fatigue; shortness of breath; poor appetite; nausea; and swollen ankles, legs or hands.
Persistently foamy urine is a telltale sign of CKD that may be due to damage of the filtering apparatus in your kidneys.
As your kidneys filter blood, they take out waste products, while keeping substances your body needs, such as proteins.
When your kidneys are damaged, they may not be able to retain proteins properly and high levels of protein pass into your urine.
The extra protein causes urine to become foamy.
This typically happens in kidney disease states, such as glomerulonephritis (inflammation of the tiny filters in your kidneys), vasculitis (inflammation of the blood vessels in the body) or advanced diabetic kidney disease.
CKD does have a tendency to run in families, so some people are genetically more likely to develop the disease.
Genetic disorders such as autosomal dominant polycystic kidney disease, can also lead to serious kidney problems.
CKD is more common in certain groups, including African-Americans, Native Hawaiians, Pacific Islanders, Native Americans and Asian-Americans.
A more significant risk factor for CKD than genetics alone, however, is having a medical condition that could harm your kidneys.
The two most common are high blood pressure and diabetes.
If left untreated, over time, these diseases can weaken the tiny blood vessels within the kidneys that filter waste from the blood, making them unable to work properly.
Other conditions that can lead to CKD include polycystic kidney disease, recurrent kidney infections, obstruction of the urinary tract and disorders that cause inflammation within the kidneys, such as glomerulonephritis and interstitial nephritis.
Some medications can affect kidney function too.
Finally, CKD becomes more common as people age.
If a medical condition that affects the kidneys goes untreated, CKD will generally worsen over time.
Once the kidneys have been damaged, it may not be possible to restore the function that’s been lost.
But if an underlying medical condition is identified and successfully treated, that will often help slow the progression of kidney disease.
With some conditions, such as glomerulonephritis, kidney disease can be cured with treatment.
This is particularly true when kidney disease is identified in its early stages.
Medication and lifestyle changes, such as losing weight, quitting smoking, and eating less animal protein and salt, may also be necessary to keep kidney disease in check.
A nephrologist – a healthcare provider who specialises in kidney care – can work with you to identify specific steps you can take to help control your CKD. – Mayo Clinic News Network/Tribune News Service