SICKLE CELL AND FATIGUE

Sickle cell disease (SCD) is a group of genetic hematologic disorders that is characterized by chronic hemolytic anemia and vaso-occlusion.   This extremely challenging disease is of global concern. The World Health Organization (2010) reported that “Each year over 300,000 babies with severe forms of these diseases are born worldwide.” In the United States, sickle cell anemia occurs in approximately 1 in 500 African American live births and 1 in 36,000 Hispanic American live births (National Heart, Lung, and Blood Institute, 2010).

The symptom most frequently associated with SCD is pain, which often occurs in the form of sudden, severe episodes called “crises.” Historically and justifiably, investigators have focused on improving sickle cell pain. However, another common symptom of SCD is fatigue.

In SCD, the pathophysiology of the disease process, such as the profound rupture or destruction of red blood cells, and unpredictable vaso-occlusive crises, indicates that individuals with SCD may be at risk for both acute and chronic fatigue.

Fatigue is recognized as “An overwhelming, debilitating, and sustained sense of exhaustion that decreases one’s ability to carry out daily activities, including the ability to work effectively and to function at one’s usual level in family or social roles.”

These findings suggest that fatigue in SCD is prevalent and may be both acute and chronic.  Specific biological and behavioral factors of SCD that can potentially lead to fatigue are oxygen deficiency, inflammation, pain, stress, depression, and anxiety. Potential personal and disease-related factors that may affect fatigue are age, sex, ethnicity, socioeconomic status, treatments, and disease severity. 

Precursors to oxygen deficiency of SDC include low hemoglobin levels from premature destruction of sickled cells, hyperviscosity of whole blood, and decreased oxygen affinity of sickled hemoglobin. Long-term complications of SCD, particularly cardiopulmonary diseases, may contribute to oxygen deficiency as well.

CAUSES OF FATIGUE

PAIN

Pain is a common and unpredictable symptom of SCD. Ever-present vaso-occlusive ischemia due to red cell obstruction of small vessels may produce ischemic pain in almost any organ, muscle, or bone in persons with SCD. Pain may also come in the form of chronic ischemic leg ulcers; avascular necrosis of the hip, knee, and shoulder; and bony necrosis of the spine. This pain is often severe in nature and can be challenging to control.

LACK OF SLEEP

People living with SCD have reported disruptions in sleep or poor sleep during painful crises such that greater pain intensity during the day was related to poor sleep quality the same night, and poor sleep quality correlated with greater SCD pain the next day, suggesting that sleep disruption plays a mediating role between pain and fatigue.

STRESS

Stress, known to be associated with chronic illness, is prevalent in individuals with SCD. Stress has been linked to greater fatigue in both clinical and nonclinical populations.

Depression and anxiety are highly conditions that are not uncommon in chronic illness and are strongly linked to fatigue. In SCD, depression tends to occur at higher rates (18%–27%).

Reference: https://www.ncbi.nlm.nih.gov