Iron can be both a friend and a foe to the kidneys. Chronic kidney disease (CKD) is a progressive decline in kidney function, widespread among those with hypertension. Despite iron’s importance for health, its impact on the kidneys is not fully understood. Both iron deficiency and excess can play roles in CKD development. Recent studies indicate that excess iron can decrease kidney function by promoting oxidative stress and hypoxia. Chinese researchers have investigated how iron supplementation affects CKD risk in people with hypertension.
Iron is vital for maintaining health and is often prescribed to prevent anemia. However, despite the widespread use of iron supplements, their benefits for chronic diseases remain controversial. Moreover, recent studies have shown that excess iron can increase the risk of various diseases, including CKD. Animal experiments have confirmed that iron overload can contribute to CKD development through oxidative stress and cellular damage.
Some studies indicate a connection between elevated ferritin levels—a marker of iron overload—and the risk of hypertension. Additionally, high doses of iron can be toxic to the kidneys, especially when combined with other medications.
Study Analysis
In this study, data from nearly 428,000 participants were analyzed:
- 55% were hypertensive patients, of which 37% were on antihypertensive medications and 63% were not.
- 45% were non-hypertensive participants.
Overall, 3% of participants took iron supplements.
Iron Increases CKD Risk by 12% in Hypertensive Patients
Iron intake combined with antihypertensive medications increased CKD risk by up to 29%. However, no correlation was found between iron intake and CKD in non-hypertensive individuals.
Compared to non-hypertensive participants not taking iron, the risk of CKD in hypertensive individuals taking both iron and antihypertensive medications increased by 89%. High body mass index (BMI ≥ 30 kg/m²) and unhealthy diets also increase CKD risk with iron intake.
Figure 1: Association between Iron Supplementation, Hypertensive Status (Normotension or Hypertension), and Antihypertensive Medication Use (No Medications or With Medications) and CKD Incidence
Source Image: https://www.mdpi.com/2072-6643/16/14/2355
Conclusion
Individuals with hypertension, especially those on antihypertensive medications, are more prone to iron overload when taking iron supplements. Excess iron can enhance lipid oxidation and cause oxidative stress, leading to cellular damage. Iron overload can lead to ferroptosis—cell death where excess iron damages cell membranes and causes cell destruction. Ferroptosis contributes to vascular calcification in CKD. Additionally, individuals on blood pressure medications often have diabetes and high cholesterol, which increases the risk of CKD.
Iron overload caused by iron supplements can form stable iron chelates with medications, altering the drugs’ actions and metabolism. Furthermore, iron overload-induced oxidative stress negates the antioxidant effects of some antihypertensive drugs, significantly reducing their efficacy. Animal experiments have confirmed that some antihypertensive drugs can disrupt iron homeostasis, evidenced by slight increases in kidney iron levels, which interact with iron supplements and lead to kidney damage, increasing the risk of chronic kidney failure.
Iron supplements can be dangerous for hypertensive patients, especially those taking blood pressure medications—the risk of CKD increases by 12%. However, iron intake is not associated with CKD in people with normal blood pressure.
Useful article, necessary information? Share it!
Someone will also find it useful and necessary:
