A recent study on 475 veterans with high blood pressure has found that accumulation of lead in the body has a direct relation with high blood pressure that’s hard to treat. These new finds are important as they not only explain why some people with high blood pressure are drug resistant, but they also pave the way for new treatment methods.
Dr. Sung Kyun Park, an associate professor of epidemiology and environmental health sciences at the University of Michigan School of Public Health in Ann Arbor explains that accumulated lead in the body which is measured by the amount deposited in the outer layer of the shin bone is something that’s ignored as a risk factor to drug-resistant blood pressure. Perhaps medical experts should start taking the amount of lead, specifically the amount found in the tibia (shin bone) as a factor as well when diagnosing patients.
The relationship between resistant hypertension and lead
The main focus of this study was not to see how lead affects normal blood pressure. Drug-resistant blood pressure is a persistent form of blood pressure that does not get better despite the treatment measures taken. Treatment measures in this case usually refer to lifestyle changes and drug-related medication.
People who have to take four or more drugs to regulate their blood pressure are also considered to have drug-resistant blood pressure. How does lead affect this type of blood pressure? Dr. Park reviewed multiple studies and in their published work, they cite quite a few. The cited works show the positive link between blood lead and high blood pressure. It was also suggested by the study that high blood lead may result in cardiovascular-related deaths.
There are also biological mechanisms through which lead in the body can lead to hypertension. For example, blood lead can disrupt blood vessel regulation and the progression of atherosclerosis. However, blood lead and blood accumulation on the bone are two different things. That’s where Dr. Park’s study comes in.
Dr. Park and his team analyzed data on 475 veterans with high blood pressure. The dataset they worked on included readings of blood pressure, blood pressure medication, and levels of lead in blood, kneecaps (patella), and shin bones (tibia). Amongst the 475 men, 97 of them were found to have resistant hypertension.
In their analysis, they took many confounding factors into account which might’ve affected the accuracy of the results. The researchers looked at age, race, income, education, weight, smoking status, further lifestyle, socioeconomic, and demographic factors. The results were adjusted accordingly and a highly sifnificant correlation was found between lead buildup in the shin bone and increased risk of resistant hypertension.
It was found that every 15 micrograms extra lead per gram of bone in the tibia is linked to a 19 percent higher risk of developing resistant hypertension.
Although the results of this study are quite significant, there are a few limitations. The study was conducted on a small sample, of only veterans. It’s possible that these people could also have resistant hypertension due to taking unprescribed drugs or due to taking over-the-counter medication.
Furthermore, the study was only conducted on “white males”, it’s possible that the results may have come out differently for women. Blood pressure measurements can also vary due to different apparatus in a doctor’s office. Since the researchers used data that was already available, they didn’t take their own measurements. Therefore, the study is not perfectly accurate but it does provide something to research more on.
It’s been known for years that lead is bad for our body. Steps need to be taken to limit the exposure to lead. Moreover, more research needs to be done to see the effect of lead on hypertension. If it is indeed a significant risk factor, then treatment methods will need to be adjusted accordingly.