Restless legs syndrome (RLS) is one of the few neurological conditions known to run in families. This condition causes your legs to feel uncomfortable while sitting or lying down. The discomfort can only be alleviated by getting up and moving around. Obviously, these symptoms can significantly impact your ability to sleep. Travel becomes difficult as well because of hardship of sitting for long periods. A recent study published in Archives of Neurology looked at how commonly RLS affects the family members of those diagnosed with it, and how cases that run in families differ from cases that do not.
The researchers recruited 249 people who had participated in a previously completed, 15-year RLS study. They interviewed these people about their symptoms and took their family histories. Researchers were particularly interested in whether the RLS sufferers had any family members with RLS. It turned out that 192 of the 249 people interviewed had first-degree relatives (i.e. siblings, parents, or offspring) with RLS. These cases and the cases of affected family members were designated as familial restless leg syndrome (fRLS). The 57 cases without family involvement were designated as sporadic (sRLS). These data established that 77 percent of RLS cases are familial.
Among the familial restless legs syndrome cases, which numbered 671 in total, 447 occurred in women and 224 in men, making women twice as likely as men to be affected by fRLS. Siblings of people with familial restless legs syndrome were much more likely to develop the condition than offspring, although offspring did exhibit an elevated risk as well. The average age at which symptoms of fRLS first appeared was 28 and the average disease duration at the time of the interviews was 24 years.
The researchers also looked at how familial restless legs syndrome differs from sporadic restless legs syndrome. They found that cases of familial restless legs syndrome developed at a significantly younger age than cases of sporadic restless legs syndrome. Familial RLS sufferers also had a longer disease duration and slightly higher severity scores. The researchers pointed out that these data might be a little misleading, since people who were found to have familial restless legs syndrome had more siblings than people who did not. This may mean that the diagnoses of familial restless legs syndrome versus sporadic restless legs syndrome may have had more to do with family size than actual genetics.
Now that this research has characterized fRLS, doctors may be able to enhance screening procedures for siblings of people with RLS. Certainly, if you have a brother or sister with restless legs syndrome you should be aware that you are significantly more likely than the average person to develop the condition. You can use this knowledge to prepare for that eventuality, or ask your doctor about steps you could take to try to prevent it.