John Singleton: High Blood Pressure and Strokes


john singletonJohn Singleton was a film and TV director, screenwriter, and producer who, in 1991 at age 24, became the first African American and the youngest person ever to be nominated for the Academy Award for Best Director, for his film Boyz n the Hood.  He used his personal experience of growing up in violence-ridden south central Los Angeles, and having to move between the homes of his unmarried parents, to write and direct many films and television shows about black inner-city life and racial tensions.  In 2002, the United States Library of Congress deemed Boyz n the Hood "culturally significant" and selected it for preservation in the National Film Registry.
Singleton had high blood pressure for many years. At age 51, on April 17, 2019, he returned from a trip to Costa Rica, was unable to walk, lost consciousness and was hospitalized at Cedars-Sinai Hospital.  He was diagnosed as having had a stroke, remained in a coma and was kept on life support with no brain activity for 13 days.  He died after his family decided to take him off life support. 

Strokes are a Medical Emergency
Each year, strokes kill more than 185,000 North Americans and permanently cripple far more than that. Strokes are caused by:  
• a clot blocking blood flow to the brain, or 
• a blood vessel bursting to bleed into and crush parts of the brain.  
The brain controls breathing, so a person stops breathing after just three minutes of his brain not receiving any oxygen though the bloodstream. If the blood flow is only partially obstructed, parts of the brain start to die in three hours or less.
If you suspect a person is having a stroke, call 911 and get that person to the hospital as soon as possible. The longer you wait, the greater the brain damage.  The American Stroke Association suggests that you remember the mnemonic 911FAST: if you see a person suddenly develop Face drooping – Arm weakness – Speech difficulty – Time to call 911.  Other signs of a stroke include difficulty walking, seeing, or understanding another person, numbness or paralysis of the face, arm, or leg, or sudden headache (although strokes are often painless).  
Most stroke victims will not benefit from CPR (cardio-pulmonary resuscitation), but if you are trained in CPR and hear no heartbeat, feel no pulse and the person is not breathing, it is reasonable to start CPR while you are waiting for an ambulance.
How High Blood Pressure Causes Both Types of Strokes
Clotting: High blood pressure widens the smallest of the small blood vessels to damage their inner walls to cause fibrous scar tissue and fat to deposit in them to form plaques (The Lancet, Dec 27, 1975;306(7948):1283-1285).  A stroke occurs when a piece of a plaque breaks off to cause bleeding followed by clotting.  The clot can extend to cause a stroke by blocking completely all blood through that artery. More than 80 percent of strokes are caused by clots.
Bleeding: High blood pressure weakens the inner lining of an artery by replacing the normal inner lining with plaques to widen the arteries to cause aneurysms and eventually for the artery to burst to cause bleeding into the brain (Clin Exp Pharmacol Physiol, Jul 1999;26(7):563-5).
People who have a first stroke have an 80 percent chance of surviving that stroke, but they also have a 10 percent chance of having another stroke and dying in the following year (BMJ, 2009;338:b1279).  Their risk of having a second stroke in the next 10 years is 43 percent (Stroke, 2004;35:731–5).  If their blood pressure is reduced to normal, the chance of having a second stroke is reduced by more than 30 percent (Int Arch Med, 2009;2:30).  That means that people who have had a stroke must do everything in their power to reduce their high blood pressure to normal by taking as many medications as needed and changing the lifestyle factors that cause high blood pressure (CMAJ,  Jan 8, 2013;185(1):11–12).

Treatments for Strokes
If you have a clot blocking the blood flow through an artery bringing blood to a part of your brain, doctors can inject tissue plasminogen activator (tPA) to dissolve the clot and open up the artery. However, you have very little time to get this treatment to prevent a part of the brain from dying.  Other treatments are to have a surgeon remove the clot that caused a stroke, or open the skull and remove the excess blood to relieve the pressure crushing the brain.  A surgeon may also be able to fix an aneurysm in which a weakened and swollen blood vessel burst to bleed into and crush the brain. These surgical treatments must be done as soon as possible.
What You Should Not Do
• Don't let the victim talk you out of calling 911. Trained emergency responders can start specific treatments as soon as they arrive. 
• Don't let a potential stroke victim drive himself to the hospital.
• Don't let the person go to sleep.  It is common at the start of a stroke for patients suddenly to feel sleepy. 
• Don't feed them. Stroke patients can vomit and then aspirate the food into their lungs and die from the food blocking their airways.
• Don't give the patient aspirin.  If the person has a stroke caused by bleeding into the brain, the aspirin can kill him or her. Soon after the person arrives at the emergency room, a CT scan will tell if it is a bleeding stroke or a clot. 
• Don't cancel the emergency call if the patient feels better.  The symptoms of a stroke can temporarily improve before they become more severe. 
My Recommendations
If you think that someone is having stroke, dial 911 immediately. Every second counts.  Strokes are caused by clots blocking arteries or bleeding into and crushing the brain.  Recent data show that you have up to 13 hours after first symptoms of a stroke start to have injections that dissolve the clot and up to 24 hours after the start of a stroke to have surgeons remove the clot (New England Journal of Medicine, May 9, 2019).
Most cases of high blood pressure are caused by or made worse by unhealthful lifestyle habits and most can be prevented with lifestyle changes and treatments.   The same lifestyle factors that cause high blood pressure increase risk for strokes, heart attacks and dementia.  High blood pressure, high cholesterol and diabetes are major risk factors for strokes and risks for all of these conditions are increased by: 
• overweight, particularly storing fat in your belly 
• a diet high in pro-inflammatory foods  (such as meat, sugar-added foods and drinks, and fried foods)
• not eating enough of the anti-inflammatory foods (vegetables, fruits, whole grains, beans, nuts and other seeds)
• not exercising
• drinking alcohol
• exposure to smoke in any form
• heavy use of recreational drugs
• some environmental pollutants 
See my report on Blood Pressure Guidelines
January 6, 1968 – April 29, 2019