Familial amyloid polyneuropathy (FAP) is a progressive disorder that can severely impact the quality of life of patients, causing emotional and psychological distress. According to a study that appeared in the Journal of Community Genetics, FAP patients and members of their family could benefit from additional psychological and psychiatric support.
Transthyretin-related familial amyloid polyneuropathy (TTR-FAP) is an inherited progressive disease caused by the production and accumulation of an abnormal protein encoded by a mutated version of the TTR gene. The protein produced in the liver will accumulate throughout the body, leading to different symptoms depending on the organ affected.
For many years no treatment was available for these patients, who generally died an average of 11 years after the onset of symptoms. But since 1990, liver transplant has brought hope for these patients, preventing production of the abnormal TTR protein and consequently delaying the progression of the disease.
More recently, Pfizer’s Vyndaqel (tafamidis) has become an available therapy for TTR-FAP. Approved in Europe and under clinical development in the U.S., this new drug has been shown to stabilize the TTR protein, preventing its abnormal accumulation in the body.
Despite the many advances made to develop new treatments targeting this disease, TTR-FAP still represents a heavy burden for patients and their families.
In the study titled “Life paths of patients with transthyretin-related familial amyloid polyneuropathy Val30Met: a descriptive study,” a team of Portuguese researchers evaluated the impact of TTR-FAP on patients’ personal, social, and family life events.
Portugal is one of the few countries in the world — the others are Sweden, Japan, Brazil and Majorca — where the rate of TTR-FAP is highest, ranging from 1 in 1,000 to 1 in 10,000 people. In other countries like the U.S. and most of Europe, the rate is much lower, at around 1 in 100,000 people.
TTR-FAP is considered extremely rare. Researchers believe that only about 10,000 people in the world have the disease, but exact numbers are difficult to pin down because the disease is difficult to diagnose.
The study included 81 asymptomatic individuals who were carriers of the disease-related TTR genetic mutation, 109 diagnosed TTR-FAP patients, and 19 family members with no established diagnosis. All participants responded to two questionnaires addressing social life aspects, and personal and familial clinical history.
The team found that 96.3% of the participants had contact with the disease prior to their diagnosis. In 53.8% of those surveyed, the mother was affected by the disease; in 43.3% it was the father. At the time of the study, 71.8% of the participants indicated that their parent with TTR-FAP was deceased.
For 37.2% of respondents, the onset of the parent’s disease was a very important event, which implied life changes with psychological and familial impact. In 44.9% of respondents, this event took place before they were 14 years old, forcing them to become the parent’s caregiver or to be raised by others. These findings showed that these patients have to face stressful situations with a heavy psychological burden from an early age.
“This disease and its life implications pose a significant psychosocial burden since childhood,” the researchers wrote.
In addition, 26.5% of all participants reported having had psychological or psychiatric problems in the past, mostly often depression and anxiety. About 21.2% of the patients were taking medication such as antidepressants or tranquilizers.
These findings showed that TTR-FAP patients and their relatives are a group that is vulnerable to emotional stress and the development of psychological illnesses. As a result, the researchers suggest that “psychological and psychiatric support must be available for these patients and their families, including young children.”
To improve the care and quality of life of these patients, the authors believe that a multidisciplinary team is required with genetic counselors, clinical psychologists, and psychiatrists working together.