Stroke Diagnosis

According to the National Institution of Health's extensive article on stroke diagnosis, a stroke is diagnosed by observing signs and symptoms, analyzing a patient's medical history, a physical exam, and results from several medical tests.
     Signs and symptoms are one of the predominant methods of stroke diagnosis, because stroke manifests physically in quite significant ways. Examples may include things such as sudden weakness, paralysis (typically on one side of the body), an inability to speak or comprehend speech, vision problems, confusion, respiration difficulty, balance and coordination problems, loss of consciousness, and headache with intense, rapid onset. These symptoms are experienced differently by different individuals, and can vary in intensity and duration. If these symptoms occur, urgent medical attention is needed, in order to limit the damage inflicted by stroke.
     There are several factors that may play into stroke risk, including things such as a family history of stroke incidence, high blood pressure, smoking, and heart disease. In a physical exam, a physician may examine coordination, balance, mental alertness, speech clarity, as well as other factors that could be indicative of stroke occurrence.
     Several diagnostic tests exist for determining stroke occurrence or likelihood, including tests such as brain computed tomography, magnetic resonance imaging, computed tomography arteriogram, magnetic resonance arteriogram, carotid tests, heart diagnostic tests, as well as blood tests. A brain computed tomography (brain CT scan) is an x-ray diagnostic tool that allows a physician to show bleeding in the brain or other damage that could have been caused by stroke. Magnetic resonance imaging (MRI) is used to detect brain tissue changes as well as brain damage that may have occurred in a stroke. A CT arteriogram and MR arteriogram both show large blood vessels in the brain, which can illustrate where a blood clot affected the brain most significantly, and gives blood flow information. Carotid angiography and ultrasound are both utilized by a physician to examine the inside of carotid arteries to determine blood flow success and factors that may have led to stroke. Heart tests illustrate factors of the heart, such as size and shape, valve success, and heartbeat patterns, that may influence the likelihood of stroke incidence. Blood tests may be used to determine blood clotting patterns, blood glucose levels that may mimic stroke symptoms, and thrombotic or bleeding disorders that all can influence the occurrence and severity of stroke.

Video Explanation of Stroke Diagnosis (with pictures of scans and diagnostic tests)

MRI scan of normal brain vs. damaged brain due to stroke
http://www.webmd.com/stroke/stroke-mri

CT scan showing stroke location in brain
http://www.uhnj.org/stroke/images/diagnosis/ct.jpg

References:
NIH Stroke Diagnosis
Mayo Clinic Stroke Diagnosis

Stroke Pathophysiology

     The number one cause of stroke is underlying heart or blood vessel disease. According to the Stroke Center Online, the primary pathologies for stroke include, but are not completely limited to: hypertension, atherosclerosis leading to coronary artery disease, dyslipidemia, heart disease, and hyperlipidemia. The reasoning behind this is that the greater the amount of plaque in arteries present, the more the chance of blood flow to the brain be stopped, thus initiating stroke incidence. The more heavily the arteries are clogged, the slower and more difficult blood flow, thus leaving less time to respond to this medical emergency.

Extensive Article on Pathophysiology of Stroke

     Some non-reducable risk factors include things such as age (the older one gets, the more likely stroke becomes), previous stroke (causes future strokes to become more likely), gender, ethnicity, family history with stroke, and a pre-diagnosed case of diabetes. There are also several risk factors that can be reduced with healthy diet and exercise, such as hypertension, high blood cholesterol, smoking, and regulation of diabetes and heart disease.

     The management of various heart diseases is not an easy task, but can be most controlled through diet and exercise. The greater level that plaque can be reduced, the easier it is for those in a "healthy" lifestyle to maintain their figure. 

     For the most part, when a stroke occurs, it occurs very quickly. The most time consuming aspect of this disease is the buildup of plaque in arteries that travel to or near the brain, which occurs over a long amount of time. There is increasing research that suggests that the incidence of infection and inflammation in arteries in the weeks leading up to stroke is evident and important. The interaction of plaque buildup and structural artery instability is important in analyzing the occurrence of stroke, because these are the two greatest factors that play a part in determining when a stroke occurs as well as how dangerous it may be. 

     The most dangerous aspect of stroke incidence is the lack of oxygen to the brain, whether the pathway is completely or significantly blocked. After even 4 minutes of no oxygen supply to the brain, irreversible brain damage occurs, with essentially no survivors after 10-15 minutes. This is hugely essential to understanding the need for fast and effective treatment of stroke with CPR or other lifesaving methods, because time is essential when it comes to mortality. The more time it takes to recognize a stroke and to begin it's treatment, the greater risk of mortality. 

http://blam-lab.org/publications/pdf/Papers/Krakauer07DynamicsStrk.pdf

http://www.strokecenter.org/professionals/stroke-management/for-pharmacists-counseling/pathophysiology-and-etiology/

Stroke Epidemiology

Epidemiology for Stroke:

According to the American Heart Association's "Heart Disease and Stroke Statistics: 2015 Update", in 2010, stroke was the number two global cause of death, shortly behind heart disease. In 2010, stroke mortality accounted for around 11.3% of deaths. Today, stroke is the fifth leading cause of death in the United States, killing about 129,000 people per year. 

The most significant aspect of this data is the difference in stroke incidence between ethnicities. African-Americans have been found to have a significantly higher risk of a first stroke occurrence than those of a Caucasian background. As seen in the graph below, there are large disparities in stroke mortality between ethnicities. 

http://www.heart.org/idc/groups/heart-public/@wcm/@sop/@smd/documents/downloadable/ucm_449858.pdf

Stroke mortality has been decreasing over the past several years in the United States, largely due to more effective post-stroke treatment and care. Since 2010, stroke mortality has decreased by 35%, which is a significant five year change. However, stroke still currently accounts for 1 in every 20 deaths in the United States. This is especially significant upon the consideration that many strokes can be prevented through a healthy diet and exercise regimen.

 The most significant geographical location of stroke mortality occurs in the Southeastern United States. This data isn't surprising based on a dietary analysis of this geographical region--with large amounts of fats and other unhealthy foods--in correlation with the levels of heart and arterial diseases, which also influences risk for stroke. There is also a direct correlation between age and stroke incidence, with that occurrence increasing as age increases. However, according to the Center for Disease Control, in 2009, 34% of people hospitalized for stroke were under the age of 65. While this data may be slightly outdated, that number is significant because it illustrates that stroke isn't simply an "age problem." It can be directly influenced by diet and exercise of an individual, which means that stroke occurrence needs to be addressed more frequently, in order to practice effective preventative measures. 

This video features Dr. Virginia Howard of the University of Alabama Birmingham explaining the geographical epidemiology of stroke. 

https://www.youtube.com/watch?v=oKCPBkS97a4

This chart illustrates the "stroke belt" that Dr. Howard discusses in the video link above. 

http://www.cdc.gov/dhdsp/maps/national_maps/stroke_all.htm

Sources:

http://www.cdc.gov/stroke/facts.htm

http://www.heart.org/idc/groups/ahamah-public/@wcm/@sop/@smd/documents/downloadable/ucm_470704.pdf

Stroke Introduction

A stroke involves a either a partial or complete lack of blood flow to the brain, thus cutting off the transport of essential nutrients and oxygen that are vital to proper brain functioning. If blood circulation remains blocked, brain cells begin to die, which can lead to irreversible brain damage. The main form of a stroke that I will be focusing on in this blog is an ischemic stroke--that which is caused by a congested or clogged artery, thus causing ischemia, or severely reduced blood flow (Mayo Clinic).
This is a video that describes the general process of a stroke for a more clear explanation:

https://www.youtube.com/watch?v=ryIGnzodxDs

     Epidemiology of stroke: In the US specifically, stroke is becoming an increasing problem, not only accounting for almost 130,000 deaths per year. Not only this, but the prevalence of this disease is approximately 795,000 incidences per year in the United States (CDC).
     Pathophysiology of a stroke: The most influential underlying disease that can be a precursor to a stroke is heart or blood vessel disease. There are a number of influential risk factors that cannot be prevented, such as age, gender, ethnicity, and family history, but there are also controllable risk factors, such as lowering high blood pressure, lowering negative cholesterol, cessation of smoking, and control of diabetic conditions that can largely be related to and controlled by nutrition (Stroke Center).
     Treatment: An incidence of a stroke must be treated extremely quickly in order to prevent or limit brain damage to restore the nutrient supply to the brain. This could be carried out by an emergency treatment with medications, such as aspirin or an IV injection of tissue plasma activator, or by catheter insertion of medication or a mechanical clot removal method (Mayo Clinic).
     Prevention of ischemic stroke: The simplest way to prevent a stroke is by ensuring that you have proper nutrition, because a healthy diet is essential to proper blood flow in the body and to the brain. An unhealthy diet can lead to the congestion of arteries and heart disease, which increases the risk for stroke. For individuals who have experienced previous stroke, doctors may perform a surgery that "opens an artery that's narrowed by fatty deposits" (Mayo Clinic), by either a carotid endarterectomy or angioplasty and stents.
     Policy Implications of stroke: Comparatively, stroke has gotten much less attention in health policy creation than other diseases, such as AIDS, cancer, and others. Because stroke can have such a profound impact on quality of life, it needs to be addressed with more urgency. The largest issue that policy makers have been facing when articulating stroke-related policy is determining if a health implementation is effective both in outcome and cost. There has been research in different types of stroke, as well as the rehabilitation procedures for both ischemic and hemorrhagic stroke, with insufficient information to create a standard rehabilitation procedure (American Heart Association). The biggest policy implementation needs to be that of preventative measures, encouraging proper nutrition and physical activity in order to prevent the controllable precursors to stroke.

Sources:
http://www.mayoclinic.org/diseases-conditions/stroke/symptoms-causes/dxc-20117265
http://www.cdc.gov/stroke/facts.htm
http://www.strokecenter.org/professionals/stroke-management/for-pharmacists-counseling/pathophysiology-and-etiology/
http://www.mayoclinic.org/diseases-conditions/stroke/diagnosis-treatment/treatment/txc-20117296
http://stroke.ahajournals.org/content/34/2/370.full

Fried Everything and the Brain:

 The Growing Problem of Nutrition-related Stroke

http://www.caycare.com/files/2015/05/stroke.jpg