Restless Legs Syndrome and Severe Preeclampsia: A Case-Control Study

This study sought to determine whether there is an association between restless legs syndrome (RLS) and severe preeclampsia using a case-control study design.

A total of 147 patients with severe preeclampsia and 147 patients with normal pregnancies were evaluated for symptoms of RLS. In the first phase, before or immediately after delivery, participants were given a questionnaire on common complaints experienced during pregnancy. Mixed with these complaints were the symptoms that comprised the diagnostic criteria for RLS. If a participant indicated she met the diagnositic criteria, she was informed about RLS. In the second phase, a severity evaluation was performed in this population using the International Restless Legs Syndrome Study Group Rating Scale.

Among the participants, independent of the presence of preeclampsia, 13.61% met the criteria for a diagnosis of RLS. There was no statistical difference between groups (severe preeclampsia: 12.93% vs. controls: 14.29%; odds ratio [OR] 0.89; 95% CI 0.46-1.74, P = 0.37). After analysis, 65% of patients with RLS had a score on the International Restless Legs Syndrome Study Group Rating Scale compatible with "very severe" or "severe" RLS. There was again no statistical difference between groups for the combination of "severe" and "very severe" scoring criteria (severe preeclampsia: 68.42% vs. controls: 61.90%; OR 1.33; 95% CI 0.36-4.93, P = 0.66) and "very severe" alone (severe preeclampsia: 21.05% vs. controls: 4.76%; OR 5.33; 95% CI 0.54-52.73, P = 0.11).

The prevalence of RLS among pregnant women in our study was in accordance with the medical literature and avoided the probable bias caused by the high number of other symptoms experienced during pregnancy. There were no significant differences between normotensive participants and those with severe preeclampsia. In general, symptom severity was high, with a tendency toward greater severity in patients with severe preeclampsia, but this difference did not reach statistical significance.