Metabolic syndrome:
A deadly mix
As warning flags go, this one is hardly a household term.
But metabolic syndrome (MetS) has emerged as a signal of potentially life-threatening illnesses prevalent among African Americans. MetS is a clustering of risk factors discussed for over 80 years, but the term was popularized by Stanford University endocrinologist Gerald Reaven in 1988.
While experts disagree on the exact definition of MetS, the most widely accepted criteria were developed by the National Cholesterol Education Program — high blood pressure, excess weight around the waist; low levels of HDL, or good cholesterol; high levels of triglycerides, or fat in the blood; and the inability to utilize insulin effectively.
Two other conditions are often included — inflammation and an increased tendency to develop a clot within blood vessels, both indicators of heart disease.
Each condition can occur by itself, but more often they appear together. If any combination of three or more of those conditions is found together at the same time, a person is considered to have MetS and, as a result, has a greater risk of heart disease, diabetes or stroke.
In fact, the National Heart, Lung, and Blood Institute (NHLBI) estimates that a person with MetS is twice as likely to develop heart disease and five times as likely to develop type 2 diabetes as someone without MetS.
MetS is more than a medical school buzzword.
The American Heart Association (AHA) estimates that 47 million Americans — or 25 percent of the U.S. population — has MetS. The likelihood of having the syndrome increases with age. About 7 percent of the U.S. adult population in their 20s is affected, and more than 40 percent in their 60s.
The NHLBI contends that MetS may eventually surpass smoking as the leading indicator of heart disease in this country. While the percentage of smokers is decreasing, the prevalence of obesity — a major trigger of the syndrome — is on the rise.
Surprisingly, most doctors do not discuss the syndrome with their patients. Dr. Rhonda Bentley-Lewis, an endocrinologist at Brigham and Women’s Hospital Division of Endocrinology, Diabetes and Hypertension, is not one of them.
“I tell my patients if they meet criteria for [MetS] and that it’s something we use as a clinical tool to manage their risk for heart disease,” she explained.
Veronica Thomasson, 62, has three of the traits, and also suffers from type 2 diabetes.
By her own admission, Thomasson, a divorced mother of four grown children, has had medical problems as far back as she can remember.
Her high blood pressure began when she was 17, and though she was prescribed medicine to help control her hypertension, she didn’t take it. Years later, her HDL of 35 — lower than the recommended 50 — added to her peril.
When she decided to quit smoking, friends offered their homemade remedies to kick the habit.
“Some told me to suck on lemon drops,” she said. “Others offered chocolates as a solution, so I ate chocolate candy.”
That’s when her weight went out of control, jumping from 240 pounds to 314.
According to Thomasson, her weight had been distributed throughout her body fairly evenly, and her stomach was pretty flat. All of that changed.
“I noticed that when I looked down, I could not see my feet, just my stomach,” she said, before asking rhetorically, “Now when did that happen?”
At first, she wasn’t that concerned.
“My weight was not dangerous,” she said. Her 5-foot-8-½-inch frame “could hide it.”
What Thomasson did not realize is that belly fat, or “apple-shaped” obesity, is more threatening to a person’s health than fatty deposits below the hips.
Of course, Thomasson was a walking red flag.
“Gradually, I woke up,” she said after being diagnosed with diabetes. “Finally, after 37-½ years, I knew I had to do something. I needed to do something to keep on breathing.”
Although MetS is seen in all races and both sexes, there are some noted differences. In its 2008 Update, the AHA reported that the syndrome is more prevalent among Mexican Americans, affecting 32 percent of the age-adjusted population. Blacks and whites are impacted in roughly equal measure, at 22 and 24 percent, respectively.
Gender is a more significant factor. Black women have about a 57 percent higher prevalence than black men, while the prevalence in Mexican American women is 26 percent higher than that in Mexican American men.
Studies targeting particular populations can reveal a grimmer picture.
The Jackson Heart Study involved 5,300 African American men and women in metropolitan Jackson, Miss. The study found 33 percent of men and 43 percent of women had MetS — numbers much higher than the national estimates.
The cause of MetS is not precisely known, but most experts agree that both genetics and environmental factors are at play, and insulin resistance and obesity are key factors.
Insulin resistance, which can run in families, is a metabolic deficiency in which the body cannot effectively utilize the insulin it produces. Insulin allows glucose to enter the cells of the body to provide fuel for energy. Just as cars run on gas, our bodies run on glucose. If glucose cannot enter the cells, it builds up in the blood stream, causing damage to several organs.
Elevated blood glucose not only triggers diabetes, it sets in motion long-term complications like kidney failure, infections, and eye and nerve damage.
Some studies have revealed that diabetes is a more common outcome from MetS than cardiovascular disease. But either way, Bentley-Lewis explained, “MetS is a driving force for both diseases. Additionally, diabetes and cardiovascular disease are tightly linked.”
Obesity and lack of exercise are the strongest environmental factors behind MetS.
The percentage of Americans who are overweight or obese has increased from 51 percent in 1995 to almost 63 percent in 2007. Obesity on its own can increase the risk of all the other traits in MetS and is a leading cause of both heart disease and diabetes.
Body mass index, based on height and weight, is a tool that measures a person’s “desirable” weight. Measurements of 25 and above can signal a weight problem. A preferable tool for MetS, however, is waist circumference. Measurements more than 35 inches in women and 40 inches in men are red flags.
But other risk factors cannot be overlooked.
High blood pressure is more common in blacks than any other race. What’s worse, it develops at an earlier age and has more serious complications. In one analysis of the prevalence of MetS in blacks, hypertension was a contributor in 70 percent of the cases.
For the most part, MetS has no symptoms. Its most evident sign is increased weight.
The positive news is that MetS and even its consequences can often be prevented, controlled and even reversed. Generally, the first line of attack is lifestyle management.
Weight loss is key.
“[Losing] as little as 5 percent of [one’s] weight can help prevent diabetes,” said Bentley-Lewis. This translates to only 12-½ pounds in a 250-pound person.
Healthy eating and exercise are also important, as well as regular screening for cardiac risk factors.
Thomasson can attest to that.
A nurse recommended Thomasson check out the Heart and Sole Program at Roxbury Comprehensive Community Health Center, offered in collaboration with the Roxbury YMCA. She joined and has never looked back.
The program provides education and services to reduce multiple risk factors that increase the incidence of cardiovascular disease and diabetes.
The program meets once a week, but Thomasson goes beyond the minimum participation.
“I get up at 4 a.m., and by 5:30, I’m at the Y,” she said proudly.
She starts on the exercise equipment in the gym and then hits the pool for another workout. She does aerobics as well.
Equally important, Thomasson has worked on her eating habits. She has taken classes on healthy eating, and is not shy in asking for extra help in controlling her appetite.
She admits that changing her habits is not easy. “I’m from the South and was raised on ham hocks and collard greens,” she said.
She started slowly at first and eliminated white bread, pasta and potatoes from her diet, then added more fruits and vegetables.
She readily admits that she backslides from time to time.
“Bean salad is good, but sometimes it’s not what I want to eat,” she said. “It’s just not me.”
Thomasson can see an improvement.Her blood pressure, diabetes and cholesterol are all under control with medication. And her weight is going down.
But she has other goals. “I know I can reverse my diabetes,” she said. “My goal is to get off medicine for diabetes and high blood pressure.”
She knows she can do it.
A while back, her glucose reading was higher than what her doctor wanted. He recommended an increase in her medication.
Thomasson said she told her doctor she had a different plan, one that didn’t involve any more medications. “Give me three months to get it down,” she told her doctor. “I don’t want to take any more of nothing.”
Three months later, her glucose level was where the doctor ordered. |
| Veronica Thomasson works out at the Roxbury YMCA five days a week in an effort to reverse her risk factors for metabolic syndrome. Thomasson, a diabetic who takes medication to manage the illness, is determined to control her disease through exercise and healthy eating. |
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Rhonda Bentley-Lewis, M.D.
Endocrinologist
Brigham and Women’s Hospital
Division of Endocrinology, Diabetes and Hypertension
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