Byine: Mohana RavindranathCars need oil changes to keep their engines running smoothly. Some anti-aging influencers, along with a handful of scientists, believe exchanging the plasma in your blood can do a similar thing for humans to help slow biological aging. The procedure is currently offered for thousands of dollars a session at many longevity clinics.One of the first trials examining plasma exchange for anti-aging in humans, published on May 27 in the journal Aging Cell, offers early evidence that it may be able to slow the biological breakdown that comes with age, even in otherwise healthy people. The small study of 42 participants, with an average age of 65, found that those who got plasma exchange therapy over the course of a few months had lower concentrations in their blood of the biological compounds that accumulate with age, compared with a control group. The trial was sponsored by Circulate Health, a plasma exchange startup.Still, many other scientists who study plasma exchange are skeptical. Its anti-aging benefits for healthy people have “never been proven” in large clinical trials, said Dr Katayoun Fomani, an associate professor and medical director of the blood bank at the University of Alabama at Birmingham, and drawing blood and replacing plasma with added fluids could put patients at risk for unnecessary medical complications without a clear payoff.Plasma exchange is a well-established treatment for certain blood disorders, autoimmune diseases and neurological conditions, and it’s typically covered by insurance when deemed medically necessary. It is not covered for anti-aging purposes. During the therapy, a provider — typically a registered nurse or a technician — hooks the patient up to a machine that draws out blood. The machine separates and discards the plasma from the blood, replaces it with donor plasma or a substitute fluid, then returns the blood back to the patient. The substitute fluid often contains a mixture of saline and proteins, like albumin. In some cases, an infusion of antibodies or drugs may also be added to boost the immune system or fight certain diseases.Hospitals and medical centers use plasma exchange to remove particles that hasten a disease’s progression. But proponents of the procedure for improving health span and life span say it can be used as a preventive measure, to remove the inflammatory antibodies and proteins that may drive biological aging.Plasma therapy is one of several different experimental longevity procedures that involve blood transfers, including platelet-rich plasma treatment, which concentrates and injects a patient’s own blood into injured areas; and a treatment where a young donor’s blood is transfused into an older recipient.Most of the research into the anti-aging benefits of plasma exchange has been done on animals, so the findings don’t necessarily carry over to humans, said Dr Caroline Alquist, co-director of the Hoxworth Blood Center at the University of Cincinnati.Until now, the research in humans has focused on patients who already have an age-related disease. In one trial of nearly 350 Alzheimer’s patients, those undergoing plasma therapy over about 14 months saw slower or more stable cognitive decline than those who received a placebo treatment.In the Circulate Health trial, one group of subjects received an albumin infusion every few weeks or so; another got the same infusion plus an antibody to fight infections; and a control group got only saline. Researchers used dozens of biological age tests to measure subjects’ blood several times during the full three-to-six-month regimen. They estimated that the albumin and antibody group decreased their biological age by about 2.6 years, while those on the albumin regimen saw a roughly one-year reduction. People who received only saline generally saw their biological age increase during the trial.While the study is “intriguing”, and suggests that plasma exchange appears to affect subjects’ blood composition even after the procedure, it doesn’t necessarily mean that it will help people live longer or healthier, said Dr Jeffrey Winters, the chair of transfusion medicine at the Mayo Clinic.It’s also not clear if the findings are a direct result of the treatment or if they were influenced by some other confounding factor, added Dr Zbigniew M Szczepiorkowski, a professor of pathology and laboratory medicine at Dartmouth Health. Finally, while plasma exchange is a relatively safe medical procedure, it does bring risks, according to Dr Winters. The machine could fail, damaging red blood cells and inducing anemia in the patient, among other hazards. Donor plasma could also carry an infection over to the patient. nyt news service