Stroke and Lab Testing: What You Need to Know

 Stroke is a condition caused by the sudden blockage or diminished blood supply to a part of the brain.  This changes/affects body functions controlled by the part of the brain, hence reduced response or no response to stimulation at all. Stroke mainly happens when/if these brain cells do not get oxygen and nutrients made available by the fresh supply of blood. Body cells, and brain cells may get inflamed or even die if they do not get enough oxygen and nutrients, one of the reasons why stroke leaves one permanently disabled.  

Statistics show that more than 129,000 Americans die from stroke each year, with approximately 795,000 people suffering new or recurrent stroke annually. This makes stroke the 5th leading cause of death in the United States. 65% of all stroke-related deaths occur in women. In addition to causing long-term disability in most survivors, at least 25% of them are at risk of suffering another stroke within five years. 

Types of Stroke  

  • Ischemic: This is the most common type of stroke, accounting for more than 87% of reported cases. It is mainly caused by a blocked artery to the brain (thrombotic stroke). This can occur as a result of a blood clot in a narrow artery, or if the clot (in other parts of the body) breaks off and travels to the brain, commonly known as an embolic stroke. 
  • Hemorrhagic stroke: This type of stroke occurs when/if a blood vessel ruptures, causing breeding in and around the brain. This could be as a result of a head injury (from an accident) or aneurysms. Aneurysms occur as a result of high blood pressure or a genetic defect.  This is the most dangerous type of stroke, which almost always leads to death.  

Risk Factors 

The most common risk factors include: 

  • Diabetes mellitus  
  • High blood pressure  
  • Dangerously high cholesterol levels  
  • Age (seniors have a risk)  
  • Hereditary genetics  
  • Race (African Americans have a higher risk of stroke when compared to Caucasians)  
  • Sex (more men suffer a stroke as compared to women, while more women succumb to it quickly)  
  • Sickle cell anemia   
  • Antiphospholipid antibody syndrome  
  • Leading an unhealthy lifestyle (lack of exercise, drug abuse, and unhealthy eating habits)   

Signs and Symptoms

Most people will have one or more mini strokes, commonly known as TIAs (Transient Ischemic Attacks), before having an actual one. These mini strokes should serve as a warning and a reason to seek medical attention as soon as possible. Symptoms of stroke can be persistent, with TIAs fading off within no time. The most common symptoms of TIA or Stroke include:  

  • Severe, unexplained headache  
  • Trouble talking, sudden loss of speech, and difficulties understanding what is being said  
  • Sudden loss of coordination, balance, and trouble walking  
  • Paralysis of the leg, arm, or face (on one side of the body), sudden weakness and numbness 
  • Unexpected difficulties in seeing with one or both eyes and blurred vision.   

Tests  

Doctors mainly use non-laboratory testing for stroke diagnosis. These include several imaging tests, a neurological and physical exam. Researchers are, however, in the process of finding laboratory tests that could be used in stroke diagnosis, screening, treatment, and management. Stroke biomarkers may also come in handy in the future.  

Some of the feasible biomarkers that could be used in risk assessment include N-methyl-D-aspartate neuroreceptors (NMDAR), Lp-PLA2, and NT-PRoBNP. Antibodies to metalloproteinases (MMPs) and NR2A/2B are potential candidates for stroke diagnosis as well. A panel of biomarkers could be used in both risk assessment and diagnostic tools for stroke. All these are, however, in the research stage, hence, yet to be tested.  

Some lab tests may also be ordered to assess a patient’s risk. These include:  

More tests may be required to identify situations that could increase your risk. These include: