Is Anesthesia Risky for People with MTHFR?
MTHFR deficiency is a genetic mutation that results in elevated levels of homocysteine in the blood (hyperhomocysteinemia). This has been linked to risks with nitrous oxide, a major component of anesthesia. N2O inhibits methionine synthase, the enzyme required for converting homocysteine to methionine, which may further increase homocysteine levels.
This article will explain the interaction between MTHFR, nitrous oxide, and anesthesia and the potential risks for people with MTHFR.
MTHFR, Nitrous Oxide, and Homocysteine
Nitrous oxide (N2O) is a colorless gas that is a major component of anesthesia used on patients undergoing medical procedures, usually in dentistry. It acts quickly, provides pain relief, and is eliminated from the body within a short period. It is also relatively low cost.
However, N2O effectively destroys vitamin B12 in the body, which means B12 is not available to be used by methionine synthase in the conversion of homocysteine to methionine. As a result, conversion does not occur, and homocysteine remains elevated. This is especially serious for those with MTHFR as these individuals are already at risk of higher homocysteine levels.
Nitrous oxide use also means B12 is not available to function as a cofactor in producing succinyl CoA(Succinyl-coenzyme A), a mitochondrial enzyme involved in ATP (Adenosine Triphosphate) production, the citric acid cycle, ketone metabolism, and red blood cell formation.
Several studies have shown that short-term exposure to nitrous oxide increases plasma homocysteine, which can last for several days.
One study involving 90 ASA (American Society of Anesthesiologists) Class I-III patients (patients with severe systemic disease) found that those with MTHFR mutations developed higher plasma homocysteine concentrations after treatment with nitrous oxide anesthesia than those without the mutation. This was associated with an increase in postoperative myocardial ischemia (a lack of blood flow and oxygen to the muscles of the heart).
MTHFR and General Anesthesia
General anesthesia is a risk to those with MTHFR if it contains nitrous oxide. Nitrous oxide cannot produce general anesthesia when used alone, which is why it is combined with other agents to induce a sedative/general anesthetic effect.
Acute increases in homocysteine caused by N2Ohave been linked to impaired endothelial function and procoagulant effects, suggesting an increased risk of postoperative myocardial ischemia. The effects of N2O-induced homocysteine increases are responsible for myocardial infarctions occurring on the first postoperative night.
However, another study involving 500 patients found that acute homocysteine increases were not associated with perioperative cardiac troponin increase after N2O anesthesia. Troponin is a protein that appears in the blood only when the heart muscle is damaged, as in a heart attack.
Nitrous oxide is also linked to vitaminB12 deficiency, which can cause spinal cord degeneration and various neurological symptoms such as ataxia, paresthesia, and loss of muscle function.
General anesthesia that does not contain N2Ois safe for those with MTHFR. A study involving patients treated with sevoflurane and propofol for anesthesia induction showed no harmful effects on homocysteine levels in those with MTHFR. Halogenated and intravenous anesthetics are also generally considered safe for patients with MTHFR.
Those with MTHFR deficiency face numerous health risks due to this enzyme's crucial role in the body. Although symptoms vary between individuals and variants, MTHFR gene mutations cause low or deficient levels of folate and B12, which has a range of downstream effects.
The increase in homocysteine levels means that those with MTHFR are at higher risk of cardiovascular and thromboembolic diseases. Hyperhomocysteinemia predisposes patients to venous and arterial thrombosis with a three to six-fold increased risk compared to the normal population.
MTHFR patients must be aware of how to support their health. This includes supplementing with methylfolate and methylated vitamin B12, active forms which do not require the MTHFR enzyme to be used in the body.
Supplements containing these activated vitamins are available in the Methyl-Life® product range, designed specifically for those with MTHFR. Recommended supplements include L-Methylfolate, which can bypass the MTHFR mutation and is immediately available for use in the body.
Active vitamin B12 is vital if an MTHFR patient is exposed to N2O. Supplementation with B vitamins before anesthesia was shown to blunt the increases in homocysteine caused by nitrous oxide.
In addition, B12 functions alongside folate as a crucial component of the methylation cycle and homocysteine conversion. Methyl-Life® offers Active B12 as a powerful independent formula or in combination with Methylfolate for maximum convenience and bioavailability.