A striking finding of the poll results was the marked regional variation in prevalence of RLS symptoms (Fig 1). Those patients from the northeastern United States were statistically less likely to be at risk for RLS than those from other areas (p < 0.05). Those from the south were about twice as likely to have frequent or occasional symptoms of RLS than those from any other region; when we analyzed the data comparing those patients who had uncomfortable leg sensations every night or almost every night, those from the south were statistically significantly more likely than those from other geographic areas to be in this group (p < 0.05). Several lifestyle factors were associated with RLS symptoms; those who reported being unemployed and being cigarette smokers were more likely to report RLS symptoms (p < 0.05). The presence of many of the medical conditions included in the NSF survey, including hypertension, arthritis, gastroesophageal reflux disease, depression, anxiety, and diabetes were associated with an endorsement of RLS symptoms (p < 0.05); there was a trend (p < 0.10) for endorsement of RLS symptoms by those with heart and lung disease. read only
We identified persons at risk for sleep apnea in this survey by use of the Berlin questionnaire. Overall, 26% of respondents were at risk for sleep apnea. Of those who were at risk for RLS, 52% were at risk for sleep apnea, compared with 23% of those who were not at risk for RLS (p < 0.05).
There were also striking associations for those patients who were at risk for RLS and sleep behaviors; those who were at risk for RLS were more likely to sleep < 6 h a night, to endorse symptoms of insomnia, and to have body twitches/movements (p < 0.05). In addition, they were more likely to stay up longer than they had planned more than a few nights a week, to take > 30 min to fall asleep, and to report daytime fatigue than those who were not at risk for RLS (p < 0.05).
Figure 1. Regional variation in the endorsement of RLS symptoms in a representative sample of US adults. Respondents from the northeastern United States were less likely to be at risk for RLS symptoms (p < 0.05).