Researchers Identify Flaws in Chronic Illness Studies, Explore New Lyme Diagnostic
A group of 16 researchers from Rutgers University, the National Institutes of Health, Rockefeller University, and the Icahn School of Medicine at Mount Sinai published an article in the journal Brain identifying recurring methodological problems in studies of infection-associated chronic illnesses, such as post-treatment Lyme disease syndrome and Long COVID. Separately, a study led by Tufts University School of Medicine published in Infection and Immunity examined a potential new method for diagnosing Lyme disease using anti-lipid antibodies.
Recurring Study Design Flaws
The Brain article outlines specific methodological issues that the researchers argue are common across studies of infection-associated chronic illnesses.
- Failure to Confirm Active Infection: The authors state that many studies do not verify that participants had a confirmed active infection. For example, studies may rely on antibody tests or the presence of a bull's-eye rash for Lyme disease diagnosis. The researchers note that Lone Star tick bites, drug reactions, and other conditions can produce similar rashes and symptoms, which could lead to the inclusion of participants with diseases other than Lyme disease.
- Inadequate Control Groups: The article identifies the use of insufficient or inappropriate comparison groups as a recurring problem.
- Improper Sample Handling: Issues with how biological samples are collected, stored, or processed are also cited as a common flaw.
- Grouping of Heterogeneous Patients: In studies of Long COVID, the authors note that patients with potentially different underlying mechanisms are often grouped together, which may obscure results.
"Studies cannot produce concrete conclusions about Lyme disease if it is uncertain whether patients actually had Lyme disease or a condition that mimics it." — Steven Schutzer, Rutgers New Jersey Medical School
The authors point to multiple sclerosis research as an example where rigorous study design eventually led to the development of FDA-approved treatments, despite the underlying cause of the disease being unknown at the time.
Up to 20% of the approximately 476,000 annual U.S. cases of Lyme disease are estimated to develop post-treatment Lyme disease syndrome, according to information in the analysis.
Quotes from the Researchers
- Steven Schutzer (Rutgers New Jersey Medical School, corresponding author) stated that studies cannot produce concrete conclusions about Lyme disease if it is uncertain whether patients actually had Lyme disease or a condition that mimics it.
- Avindra Nath (National Institute of Neurological Disorders and Stroke, NIH) said the proposed framework provides rigorous guidelines for conducting clinical trials in this patient population.
- Jacqueline Becker (Icahn School of Medicine at Mount Sinai) stated that patients deserve clinical trials that confirm diagnoses, choose appropriate comparison groups, and treat patient populations as distinct.
Potential New Diagnostic Markers for Lyme Disease
A separate study from Tufts University School of Medicine focused on a group of immune molecules known as anti-lipid antibodies as a potential tool for diagnosing Lyme disease. The study analyzed blood samples from 199 people diagnosed with Lyme disease, as well as healthy controls and patients with conditions including lupus and Long COVID.
Key Findings
- Three anti-lipid antibodies (anti-phosphatidic acid (αPA), anti-phosphatidylserine (αPS), and a third) were found at higher levels during infection.
- The antibodies αPA and αPS were elevated at the time of diagnosis, including in some patients who tested negative on standard Lyme disease tests.
- Patients with persistent symptoms after treatment were more likely to have elevated αPS levels months after initial diagnosis.
- Elevated αPS levels were common in patients with persistent Lyme symptoms but were largely absent in patients with other autoimmune conditions studied.
Limitations and Next Steps
The researchers stated that the findings do not yet support the use of this method as a new clinical test. Larger studies are needed to validate the markers. The research team is currently conducting a multi-institution study following patients for up to 15 months after their initial diagnosis to further assess the utility of these antibodies. The study also suggests that different types of immune dysfunction may be driving persistent symptoms in Lyme disease.