Homocysteine Test

A homocysteine test is performed to diagnose deficiencies of vitamins B12, B6 or folic acid. It is also used to check for homocystinuria, which is a rare inherited disorder that prevents the breakdown of certain proteins and increases the levels of homocysteine in the blood and urine. It is also used as a screening test for people with a high risk of heart disease or stroke and for monitoring patients with heart diseases. A healthcare provider may suggest a homocysteine test if he/she observes the following symptoms:

• Weakness
• Dizziness
• Fatigue
• Pale skin
• Sore mouth and tongue
• Tingling in arms and legs
• Unexplained anaemia
• Recurrent abortions 
• Infertility
• Delayed development 
• Failure to thrive in babies
• Elderly aged above 75 years
• Vegetarians who do not take B12 supplements
• Persons using drugs that may lead to folic acid deficiency 

As this test is expensive, it is not recommended routinely. In general, adults can get their homocysteine levels checked every 3 to 5 years and newborns every 3 to 5 days.

Fasting for 7 to 10 hours is usually recommended before the test. 

A needle will be inserted into a vein of your arm to withdraw a blood sample- you may feel a slight sting at the site of needle puncture. The procedure is usually simple and is completed within a few minutes. The collected sample will be put into a special tube which separates serum from blood and sent to a lab for analysis. 

Normal results:

Male: Range of 1-2.12 milligrams/litre (mg/L)
Female: Range of 0.53-2 mg/L

Abnormal results: Higher than normal homocysteine levels indicate the following:

• High risk of heart diseases
• Smoking
• Vitamin deficiencies (B12, B6 and folic acid)
• Old age
• Use of medicines such as carbamazepine, cycloserine, isoniazid, methotrexate, penicillamine, phenytoin and procarbazine

Other possible reasons for increased homocysteine levels include

• Low levels of thyroid hormone
• Renal illness
• Psoriasis
• Family history

Following a healthy diet rich in vitamins and folic acid helps in the reduction of homocysteine levels in the body. However, there is no evidence that this would help in reducing the risk of heart disease or stroke in the future. Patients with high homocysteine levels are usually prescribed multivitamins as part of the treatment. Appropriate diet and lifestyle changes are also advised. Evaluation of other factors that may increase the risk of cardiovascular diseases should also be performed. If your healthcare provider prescribes medications to reduce homocysteine levels, the test may be repeated after eight weeks. 

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.