Background: Restless Legs Syndrome (RLS) is a sleep disorder cause by inadequate iron metabolism. However, no studies have identified the impact of iron in RLS patients on sleep, depression, fatigue, or quality of life (QoL). Objective: The aims of this secondary data analysis was to determine relationships (a) between serum iron with RLS symptom severity, sleep quality, daytime sleepiness, depression, fatigue, and quality of life (QoL); and (b) based on demographics, specifically age and ethnicity. Method: Data were collected on iron and ferritin concentrations in 48 persons with RLS. Results: Low serum iron levels were measured in 32% of the participants with only 1 person (4%) treated with iron supplementation. General linear models identified age and race as covariants: (a) being White (p = .047) and higher iron levels (p = .019) were independent predictors of higher social functioning; (b) being White (p = .047) and higher iron levels (p = .004) were independent predictors of less sleepiness; (c) younger age (p = .001) and lower iron levels (p = .025) were independent predictors of depression; and (d) younger age (p = .006) and lower iron levels (p = .005) were independent predictors of fatigue. Discussion: Findings from this study show that iron supplementation for persons with RLS not only improves motor and sensory symptoms but might also improve sleep, sleepiness, depression, fatigue, and QoL and should be considered by health care providers for treatment of RLS.
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