The “Ask Dr. Kevin” series is brought to you by Pfizer Rare Disease in collaboration with the National Newspaper Publishers Association (NNPA) to increase understanding of transthyretin amyloid cardiomyopathy (ATTR-CM) and the risk it poses to African Americans.
ATTR-CM is a rare and life-threatening condition that is associated with heart failure.[i],[ii] Awareness of this rare disease is low, even among healthcare providers, and symptoms of ATTR-CM often mimic other types of heart failure. As a result, ATTR-CM is significantly underdiagnosed.ii,[iii],[iv],[v]
It’s important to understand the two sub-types of ATTR-CM, wild-type and hereditary. Wild-type ATTR-CM, the most common form, is usually associated with men over the age of 60 and is not caused by a genetic mutation. Most wild-type patients are White. The second type, hereditary ATTR-CM, is inherited from a relative and is due to genetics.[vi],[vii],[viii], Hereditary ATTR-CM disproportionately affects the African American community because the most common mutation associated with hereditary ATTR-CM in the U.S. is V122I and is found almost exclusively in African Americans.ii,[ix],[x] This series will take a closer look at the signs and symptoms of hereditary ATTR-CM, while exploring the often-complicated journey to diagnosis for patients living with this condition.
The Burden of Heart Failure in the African American Community
In the U.S., African Americans experience disproportionate rates of cardiovascular disease, including heart failure and stroke ix,x and according to one study, were 45 percent more likely to die as a result of heart failure-related hospitalization than Caucasian populations in the United States.[xi] Poor cardiovascular outcomes in the African American community have been linked to a variety of factors, such as lower levels of health literacy and education, an overall lack of insurance coverage and access to quality healthcare.v,[xii] ,[xiii],[xiv]
While ATTR-CM is generally underdiagnosed in all patients, this is especially the case among African Americans with the hereditary subtype. With the disproportionate rates of heart failure, heart attacks, and other serious heart conditions in the African American community, it’s important to fully explore the underlying cause of these conditions with the help of a cardiologist.ix,x
As someone who has dedicated herself to addressing patient health disparities and access to care, including those that affect African Americans, I asked Dr. Dara Richardson-Heron, Pfizer’s Chief Patient Officer, for her perspective on the ATTR-CM patient burden in the Black community. “While African Americans are more likely to experience heart failure relative to other ethnic and racial groups, there is still a gap in understanding the underlying cause,” said Dr. Richardson-Heron. “Because awareness of hereditary ATTR-CM as a cause of heart failure is so low, many patients may never have their condition accurately diagnosed and treated, and cases continue to go undetected in the community.”
Understanding the Symptoms and Risk Factors for Hereditary ATTR-CM
Hereditary ATTR-CM is caused by a mutation in the gene that produces the transthyretin protein. As noted above, the most common mutation associated with hereditary ATTR-CM in the U.S. is V122I and is found almost exclusively in African Americans with a prevalence of roughly 3 percent.i,vi,vii,viii,iv,[xv]
Symptom onset can occur in men and women as early as their 50s or 60s although people who have the mutation may never develop symptoms of the disease. Hereditary ATTR-CM is a serious disease that can affect many parts of the body, including the nerves, heart, GI tract, liver, and kidneys. As a result, symptoms can manifest in a wide array of clinical presentations, often leading to misdiagnosis and delays in diagnosis.xiii,[xvi],[xvii],[xviii]
Since ATTR-CM often presents with symptoms that are similar to other more common heart conditions, the possibility of ATTR-CM may not be considered initially or there may be a lack of understanding of how the disease affects African Americans. Symptoms of ATTR-CM may also include non-cardiac related symptoms such as carpal tunnel syndrome (numbness, tingling and pain in the fingers), biceps tendon rupture, and pain or numbness in the lower back and legs due to narrowing of the lower spine (known as lumbar spinal stenosis). Referral to a cardiologist can help patients receive an appropriate diagnosis earlier for their condition. Understanding symptoms and having knowledge of their family’s health history can help empower patients to have more proactive conversations with their primary care physician or cardiologist about ATTR-CM.
If you’d like to learn more about ATTR-CM, including common signs and symptoms, visit: http://www.YourHeartsMessage.com.
*Dr. Kevin Williams is the Chief Medical Officer for Rare Disease at Pfizer. He pursued medicine after being inspired by his father’s work as a general practitioner in his hometown of Baton Rouge, Louisiana. Dr. Kevin is passionate about raising awareness and increasing understanding of ATTR-CM in the African American community. You can follow Pfizer on Facebook and Twitter.
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[xv] Buxbaum JN, Ruberg FL. Transthyretin V122I (pV142I)* cardiac amyloidosis: an age-dependent autosomal dominant cardiomyopathy too common to be overlooked as a cause of significant heart disease in elderly African Americans. Genet Med. 2017;19(7):733-742. doi:10.1038/gim.2016.200
[xvi] Gertz M. Hereditary ATTR amyloidosis: burden of illness and diagnostic challenges. 2017. American Journal of Managed Care.
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[xviii] Nativi-Nicolau J., Maurer M. Amyloidosis cardiomyopathy: update in the diagnosis and treatment of the most common types. 201 Current Opinion. 2018. doi:10.1097/HCO.0000000000000547