In this study, which was published in the International Journal of Clinical Rheumatology, the researchers noted that lead is a common ubiquitous environmental pollutant, and that it may be one of the environmental factors affecting the increasing prevalence of knee osteoarthritis in young adult patients. So their primary aim, according to their research paper, is to try and find detailed information about the correlation between blood lead and hyaluronic acid levels and the degree of knee osteoarthritis among a group of patients.
In order to conduct their study, the researchers first needed to gather 90 patients aged 20 to 50 years, and confirm that each and every one of them had knee osteoarthritis. All patients were subjected to both clinical and radiological assessments of osteoarthritis to confirm the severity of their conditions. Then their blood samples were taken in order to estimate the blood lead level as well as to measure hyaluronic acid levels.
According to the researchers, there are very few studies investigating the correlation between the levels of blood lead and serum hyaluronic acid in young adult patients with knee osteoarthritis, so they came into some pretty interesting results and conclusions. Based on the data that they were able to gather, the researchers say that the blood levels detected in the participating patients are on the ranges that are considered toxic by the Centers for Disease Control and Prevention (CDC). This could be attributed to the level of environmental pollution in Egypt, which has a higher exposure to lead than in other regions and populations, according to the researchers.
The research results show that there is a positive correlation between blood lead levels and the severity of both symptomatic and radiologic knee osteoarthritis. There was already an assumption that low levels of lead in the blood could cause a local toxic effect to bones and joints, and that it can only be made worse with high blood lead levels. It is also said that lead exposure could increase the susceptibility of so-called osteoblasts to environmental toxins, and that once the blood lead levels are increased, it leads to a cycle of increased tendency to toxic damage -- regardless of causality.
Meanwhile, the research data shows that there is no association between blood lead levels and serum hyaluronic acid. This discrepancy could be due to population sample, study design, environmental influence, or genetic and ethnic factors, according to the researchers. In any case, the link that they did find between blood lead levels and knee osteoarthritis gives great insight into how current methods of assessing and treating the condition could be improved in the future.
For now, research on the matter will continue, especially since the researchers have yet to clarify the exact mechanisms involved in the pathogenesis of osteoarthritis in relation to the different environmental pollutants that affected individuals are typically exposed to, including lead itself. That gives some hope that one day, a truly effective treatment for osteoarthritis can become widely available.