Anemia Linked to Restless Legs Syndrome in Lupus

Anemia could increase the prevalence of restless legs syndrome (RLS) in patients with lupus, according to a new study.

The study analyzed the relationship between the frequency and intensity of restless legs syndrome and anemia. It’s a first-of-its-kind look at International RLS Study Group Rating Scale (IRLSSG-RS) scores and anemia in lupus patients. Existing research points to an inflammation/immune system dysfunction link with restless legs syndrome.

Researchers discovered higher restless legs syndrome prevalence in lupus patients than others. Findings suggested anemia was associated with more common, more severe restless legs syndrome in lupus patients. The study appeared in the Dec. 1, 2015 issue of International Journal of Rheumatic Diseases.

Investigators divided 124 patients – 62 with lupus and 62 without – into two groups based on hemoglobin levels. Male anemia levels were less than 13 g/dL; less than 12 g/dL for females. Exclusion criteria were: diabetes, hypertension, thyroid dysfunction, acute/chronic infection, chronic heart failure, chronic obstructive pulmonary disease, kidney disease, autoimmune hemolytic anemia, vitamin B12 and folic acid deficiency, malignancy, and smoking.

Participants were assessed for restless legs syndrome symptoms in face-to-face interviews.

A restless legs syndrome diagnosis required:

• urge to move limps with senses of paresthesia/hysesthesia
• need to move; feeling relief when moving
• worsening symptoms when resting; relief when moving
• worsening symptoms in evenings/nights

The average anemic lupus patients was 40 years old – 38 for the non-anemic. Twenty lupus patients had anemia; 42 didn’t. Nineteen (30.6 percent) lupus patients had RLS. Ten anemic lupus patients (50 percent) also had RLS – their IRLSSG-RS score was 14.5 +/- 9.9. Nine non-anemic lupus patients (21.4 percent) had RLS, and their IRLSSG-RS was 9.0 +/- 8.9. RLS was more prevalent in lupus patients than the control group – 14.5 percent and 4.8 percent, respectively. [[{"type":"media","view_mode":"media_crop","fid":"45126","attributes":{"alt":"@JLPfeifer/Shutterstock.com","class":"media-image media-image-right","id":"media_crop_2176602410618","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"5118","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"font-size: 13.008px; line-height: 1.538em; float: right;","title":"@JLPfeifer/Shutterstock.com","typeof":"foaf:Image"}}]]

Among the anemic, 16 had iron deficiency, and four had chronic disease anemia. Seven iron deficient patients (43.8 percent) had RLS, as did three (75 percent) with chronic disease. Iron-deficient IRLSSG-RS scores were 14.4 +/- 10.2, and 14.5 +/- 9.9 for chronic disease.

Researchers noted the small anemic patient population as a limiting factor. They also didn’t further evaluate anemia causes.