Pregnant women often develop Restless Legs Syndrome (RLS). However, the incidence of RLS in this population was associated with race, age, and dietary factors, according to study results published in Neurology.
The study researchers analyzed data from a multicenter prospective cohort study carried out between 2009 and 2013. They recruited pregnant women (N = 2704) between the 8th and 13th week of pregnancy and assessed them for symptoms of RLS during 5 follow-up examinations. Participation in this study was reduced from 2554 at the first follow-up to 2056 at the last over the course of the study.
The women were 28.1 (standard deviation [SD]± 5.51) years old, 39.4 percent had a bachelor’s degree or higher, 25.5 percent earned less than $ 30,000 per year, and the mean pregnancy weight was 67.3 (SD, ± 15.0) kg . Stratified by ethnicity, Asian women had the lowest body mass index (P <0.0001) and the smallest waist circumference (P <0.0001), while Hispanic women had the largest waist circumference (P <0.0001) and the highest skin fold size ( P <). 0001), and black women had the highest pregnancy weight (P <0.0001) and the highest rate of anemia (P <0.0001).
RLS was reported by 18.1 percent of the women in the study. The incidence varied by ethnicity: it was more common in Asian women (21.1%), followed by white women (20.3%), Hispanic women (17.1%), and black women (15.4%; P = 0.03). After 8 to 13 weeks the incidence rate was 0.9 to 1.7 percent and rose to its peak after 24 to 29 weeks gestation (4.6 to 8.1%), while in the final assessment it rose after 38 to 41 weeks of gestation 1.2 to 2.3 percent decreased.
In all women, a higher risk of RLS was associated with increased subcutaneous fat in quintiles 4 (relative risk) [RR]1.46; 95% CI, 1.11-1.93; P = 0.01) or 5 (RR 1.46; 95% CI 1.06-2.02; P = 0.001) and age ([25-35 years: RR, 1.32; 95% CI, 1.04-1.66; P =.02] vs. [>35 years: RR, 1.41; 95% CI, 1.04-1.90; P =.03]). A lower risk was associated with multiple pregnancies (RR 0.76; 95% CI 0.64-0.91; P = 0.002).
Among Hispanic women, those with greater subcutaneous fat (quintile 4: RR 2.19; 95% CI 1.16-4.15; P = 0.02; quintile 5: RR 2.54; 95% CI 1.30-4 , 97; P = 0.01) anemia (RR 2.47; 95% CI 1.31-4.64; P = 0.01) or age from 25 to 35 years (RR 1.51; 95% CI 1 , 05-2.16; P = 0.02) were exposed to an increased risk. Hispanic women who were not in their first pregnancy (RR 0.69; 95% CI 0.50-0.96; P = 0.03) were at lower risk.
Among black women, those with larger subcutaneous fat (quintile 4: RR, 2.13; 95% CI, 1.20-3.77; P = 0.01) and waist circumference (quintile 4: RR, 2.01; 95% CI, 1.07-3.77; P. = .03) had an increased risk of RLS.
This study may have been biased by the RLS rate, which was lower than the general population (3% versus 5% to 10%). In addition, there was only one question that assessed the RLS facial expression symptom and opened up the possibility of false positive RLS cases.
“The incidence of RLS during pregnancy differed by race / ethnicity, likely due to differences in the distribution of other risk factors such as age, pregnancy BMI, and parity,” the study researchers concluded, “but future studies will understand the pathophysiological mechanisms The results are justified. ”
Na M, Wu J, Li M, Hinkle SN, Zhang C, Gao X. Emerging restless legs syndrome in pregnancy in a prospective multiracial cohort: incidence and risk factors. Neurology. 2020; 95 (24): e3438-e3447. doi: 10.1212 / WNL.0000000000011082