Road to discovery

Sickle cell disease

by Mike Porter

Wally R. Smith, M.D.

Wally R. Smith, M.D.

The pain experienced by patients suffering from sickle cell disease can be unpredictable and debilitating, but until recently, doctors have had little understanding about the frequency and intensity of this pain.

Now, a new report by Virginia Commonwealth University researchers suggests that pain in adults with sickle cell disease, a genetic blood disorder that affects approximately 80,000 Americans, is far more prevalent and severe than previous studies have shown and most patients manage even severe sickle cell pain at home rather than go to an emergency room or hospital.

According to lead author Wally R. Smith, M.D., professor of medicine and medical director of the Center on Health Disparities at VCU, the findings may change the way people view pain associated with sickle cell disease and how doctors research and treat the disease.

Sickle cell disease affects the body’s red blood cells. Normal red blood cells carrying hemoglobin are smooth, flexible and donut-shaped and can travel easily throughout blood vessels. However, sickle cell patients have stiff, crescent-shaped red blood cells that do not flow freely through blood vessels. Pain results when the irregular-shaped cells clot together, causing blockages that may lead to potentially dangerous complications that can compromise a patient’s organs.

The majority of patients are African-American, but the disease can affect people of Spanish, Portuguese, Italian and Greek decent. About 2.5 million Americans have sickle cell trait, which is the gene that causes the disease.

Through the Pain in Sickle Cell Epidemiology Study, 232 Virginia patients ages 16 or older were required to fill out daily diaries for up to six months. Patients were asked to report on their worst sickle cell pain intensity on a scale from 0 (none) to 9 (unbearable), and whether they were in a sickle cell crisis. They also were asked if they had taken medication for their pain, what kind of pain medicine was taken, if they had gone for an unscheduled physician or emergency department visit or had been hospitalized due to sickle cell pain.

“We were surprised that a third of the patients said they were in pain nearly every day.  We didn’t expect to find that,” Smith said. “That revolutionizes the idea of just how big the iceberg of pain from sickle cell disease really is.”

Smith said the report, “A Prospective Study of Daily Pain in Adults with Sickle Cell Disease,” will lead to changes in the measurement and management of pain in patients with sickle cell disease.

“We need to approach treatment of this disease as if we’re treating a phenomenon that’s going on all the time. Whatever the underlying processes that are causing pain in sickle cell disease, those are going on all the time,” he said. “Those are chronic processes. Our approach needs to be to use medications that either treat chronic pain or relieve its underlying causes over long periods of time and not simply deal with short-term crises.”

The study was published in the Jan. 15 issue of the journal Annals of Internal Medicine.