Obesity: a possible risk factor for restless legs syndrome

Prevalence, severity and associated factors of restless leg syndrome in inflammatory bowel disease patients

BACKGROUND

The association between restless leg syndrome (RLS) and inflammatory bowel disease (IBD) has often been an under-investigated and clinically misdiagnosed entity. An emphasis should be made on the severity and associated factors, as the prevalence of both entities is on the rise globally. In this study we aimed to investigate the prevalence, severity and associated risk factors of RLS in patients with IBD.

METHODS

A multi-center, prospective cross-sectional study was conducted with age and gender matched controls in the ratio of 1:3. Cases of IBD were confirmed according to European Crohns and Colitis Organization guidelines. The study recruited 377 cases and 1131 age and gender-matched controls. RLS severity and prevalence was determined using a validated International Restless Legs Syndrome Study Group questionnaire. The anthropometric and blood biochemical measurements were retrieved from the patient's medical records. Associated factors were analyzed by regression analysis.

RESULTS

The prevalence of RLS in patients with IBD and non-IBD control groups was 21.5% and 9.7%, respectively (P = 0.001). The severity index of RLS symptoms in all the three categories of mild, moderate and severe RLS was higher in the IBD group (P = 0.001). Obesity (BMI >30 Kg/m²) was more prevalent in patients with IBD with RLS than without RLS (21.9%: 10.3%, P = 0.009). Ages between 46 and 59 years (OR = 18.7 [2.6-29.4], P = 0.008), obesity (OR = 22 [2.6-29.4], P = 0.005), higher TSH levels (OR = 1.7 [1.0-3.0], P = 0.033), and lower hemoglobin levels (P = 0.028) showed a greater risk associated with RLS.

CONCLUSION

Prevalence and severity of RLS was higher in patients with IBD. The risk factors for RLS in IBD include increasing age, obesity, higher TSH, and lower hemoglobin.

Clinical characteristics of Korean pediatric patients with restless legs syndrome

OBJECTIVES

Restless legs syndrome (RLS) is a common neurological disorder but it is not sufficiently recognized in children and adolescents. It often overlaps with growing pains in children, and as a result the clinical characteristics of pediatric RLS are not well studied, especially in Asia. The purpose of this study is to investigate the clinical characteristics of pediatric RLS patients in Korea and compare it to those of adult RLS patients.

METHODS

We retrospectively reviewed the medical records of all pediatric RLS patients (≤18 years) from January 2015 to December 2018 in a regional tertiary hospital sleep center. We randomly selected adult primary RLS patients without comorbid medical disorders from our sleep center's dataset as controls. The number of controls was determined to be twice the number of pediatric RLS patients according to sample size calculation. The clinical and polysomnographic (PSG) characteristics of both groups were compared. The independent t-test, chi-squared test, and Fisher's exact test were used for analyzing quantitative data between the two groups and p < 0.05 was considered statistically significant.

RESULTS

Twenty-nine primary pediatric RLS patients and 57 adult RLS patients were enrolled. Pediatric RLS patients showed equal prevalence between sexes, as opposed to adults where there is female predominance. Ferritin level was significantly lower in pediatric patients, although it remained within the normal range. Also, pediatric RLS patients showed less severe RLS symptoms and had better sleep quality than adults did in both objective and subjective measures. In addition, PLMS was shown to be less common in pediatric RLS patients compared to adults.

CONCLUSIONS

Pediatric RLS patients showed relatively mild to moderate RLS symptoms and a smaller likelihood of experiencing PLMS than adult patients, which is comparable to similar western studies. Long-term evaluation of a patient's clinical course through multicenter clinical studies is strongly suggested for the future.

The association between obesity and restless legs syndrome: A systemic review and meta-analysis of observational studies

OBJECTIVE

Restless legs syndrome (RLS) has been reported to occur more frequently in obese individuals than in those with normal weight. In this study, a systematic review and meta-analysis was performed to explore the relationship between obesity and RLS.

METHODS

Published articles were identified through a comprehensive review of PUBMED and EMBASE from inception to the 16th December 2017. Data from studies reporting relative risks, odds ratios, or hazard ratios comparing the risk of RLS among individuals with obesity versus people with normal weight were analyzed. A random-effect model was used to calculate pooled odds ratios and 95% confident intervals (CI) for the association between obesity and RLS.

RESULTS

Findings for a total of 197,204 participants were pooled across 15 studies and were examined. Our analyses demonstrated a positive association between obesity and RLS, with an odds ratio (OR) of 1.44 (95%CI: 1.31-1.58, I² = 62.3%). Overweight subjects were also likely to have RLS, with an odds ratio of 1.29 (95%CI: 1.22-1.36, I² = 0). In subgroup analysis, women (OR = 1.42) with obesity were more likely to have RLS as compared with men (OR = 1.19).

CONCLUSIONS

Adults with obesity are more likely to suffer from RLS, with women at higher risk.