Restless leg syndrome in patients with chronic kidney disease: a hospital-based study from Upper Egypt

Chronic kidney disease (CKD) is a common cause of restless leg syndrome (RLS). RLS is under-recognized, misdiagnosed and undertreated disorder in our locality. In this study, we aimed to determine the prevalence of RLS due to CKD and its predictors.

This cross-sectional study included 520 patients [male = 200; female = 320; age: 48.45 ± 3.63yrs; uremia duration: 6.44 ± 1.65yrs; CKD5D = 400; CKD3D = 120). RLS diagnosis was done by clinical interviewing according to International RLS Study Group criteria. All underwent detailed biochemical testing and iron and ferritin levels' measurements. Insomnia, depression and anxiety severities were assessed using insomnia sleep index (ISI), Beck Depression Inventory (BDI-II) and State-Trait Anxiety Inventory for Adults (STAI-AD) scales.

RLS was found in 22.31% [ESKD = 26%, CKD3D = 10%]. Insomnia, depression and anxiety were found in 76.15%, 91.15% and 44.23%, respectively. Insomnia was correlated with depression (r = 0.488, p = 0.001) and anxiety (r = 0.360, p = 0.006) but not RLS. Multiple linear regression analysis showed that ESKD (OR = 3.8, 95%CI = 2.5-8.5, p = 0.001), inadequate dialysis (OR = 4.6, 95%CI = 3.5-8.6, p = 0.001), hyperparathyroidism (OR = 5.1, 95%CI 3.2-13.7, p = 0.0001) and peripheral neuropathy (OR = 5.6, 95%CI = 3.8-12.8, p = 0.0001) were independently associated with RLS.

The prevalence of RLS with CKD is 22.31%. It is 2.6 times more frequent and severe with ESKD compared to CKD3D. It seems that RLS may occur early with CKD and becomes worse with progressive kidney impairment. Also, insomnia, depression and anxiety are common with CKD, however, their severities were not correlated with RLS. Predictors for RLS were ESKD, inadequacy of dialysis, hyperparathyroidism and peripheral neuropathy.