NEW YORK (Reuters Health) – Patients with amyotrophic lateral sclerosis (ALS) find value in genetic testing for the disease, whether or not they have a family history of the condition, according to findings from a survey conducted by U.S. researchers.
The investigators surveyed 449 ALS patients (45 with familial ALS and 404 with sporadic ALS). In all, 156 survey respondents (34.7%) reported that they had been offered genetic testing for ALS and 105 that they had completed it. Of 75 patients who recalled the result, 21 (28%) said the result was a positive disease finding.
Genetic testing had been offered to more than two-thirds of the patients with familial ALS and to less than one-third of the patients with sporadic ALS, according to the December 20 online report in Molecular Genetics & Genomic Medicine.
Most survey respondents reported good experiences with the genetic testing process, with at least 70% agreeing with most survey statements that described the experience in favorable terms. The survey statements that fell below that threshold were those about whether a doctor/care team had explained what the results mean (59%) and whether the test results were useful to family members (62.5%).
Respondents who tested positive for an ALS mutation did not have significantly less favorable responses about their testing experiences, compared to those who tested negative. The authors interpret this finding to mean that “getting bad news did not negatively impact (the) perception of the testing process.”
“Many patients with ALS have questions about why they developed the condition. ALS genetic testing can help patients understand whether their condition is caused by a known ALS gene,” corresponding author Jennifer Roggenbuck, a genetic counselor and assistant professor at the Ohio State Wexner Medical Center, in Columbus, told Reuters Health by email.
If a harmful change is found in one of these genes, she explained, the patient has a genetic form of ALS and could become a candidate for gene-specific clinical trials or other studies. A genetic counselor could then also provide specific information about the chance that children and other family members might carry the same gene.
“Also, some specific genetic forms of ALS may be associated with a faster or slower progression of symptoms,” Roggenbuck added. “In these cases, the genetic testing can help us predict the progression of symptoms, which is another piece of information that patients are interested in.”
Current U.S. best-practice guidelines for ALS care do not provide recommendations on offering genetic testing, the report notes. The available data suggest that neurologists are likely to offer genetic testing to patients with familial ALS, but less consistently to patients with sporadic ALS.
“Historically, some doctors have assumed that because there is currently no specific treatment for genetic forms of ALS (outside clinical trials), patients would not be interested in genetic testing and therefore we should not offer it, especially if a patient has no known family history,” Roggenbuck said.
Nonetheless, research cited by the report indicates that in the past five years, an increasing percentage of neurologists internationally are offering ALS genetic testing in clinical practice.
Although only 12.5% of the current survey’s respondents indicated they’d had contact with a genetic counselor, those with counselor contact were much more likely to have been offered genetic testing than those without counselor contact.
Given the relatively less favorable responses to survey items about doctors’ explanations of results and the results’ value to family members, the authors suggest that “patients could benefit from more extensive discussion of the complex issues surrounding transmission, penetrance, and testing of family members.” They conclude that their findings support “the practice of offering testing to all ALS patients.”
The study was funded by the Neurogenetics Special Interest Group of the National Society of Genetic Counselors. The authors disclosed no pertinent conflicts of interest.
SOURCE: http://bit.ly/2mxFkBN
Mol Genet Genomic Med 2017.
Tidak ada komentar:
Posting Komentar