The mystery of the Southern stroke belt is solved

Dr. Daniel Lackland at the Medical University of South Carolina has been working for years to unravel a mystery.

It's called the "stroke belt," a swath of Georgia and the Carolinas where strokes are prevalent and often happen to people younger than me. (I turn 54 next month.)

"Even an African-American born outside the Southeast has a 50% lower risk of stroke than those born in the Southeast," he told the Emory-Georgia Tech Predictive Health Symposium this week.

Strokes are bad enough. Folks in this region are also twice as likely to require dialysis -- 5,000 of every 1 million black folks in this area must go through the procedure every few days or they die.

Lackland found the cause was clear enough -- hypertension.

"Even lean African-Americans often have high blood pressure," he said. Were we more aggressive in treating hypertension death rates among my black neighbors could drop 50%, he added

But why the hypertension? People here are no fatter than elsewhere. Finally Lackland feels he has isolated the variable.

Low birth weight. Some 14% of black babies, and 7% of white, in the stroke belt have low birth weights. The rate is going up, as we learn how to save more very premature infants.

When a very tiny infant survives it's a miracle. But what Dr. Lackland has shown is it's one with a definite sell-by date.

If your weight at birth was under a few pounds (six and a half is normal) you are at significant risk of hypertension, stroke, and kidney failure in later life.

(For readers outside the U.S., under a kilogram is bad, while 2.7 kg. is about normal.)

So what causes a higher risk of low birth weight? The CDC has known the cause of that for 20 years.

Smoking. Dr. Lackland has found that the solution to the mystery of the stroke belt was there all along, at the tip of your nose.