Spontaneous Reporting vs. Real Prevalence : Under-recognition of Restless Legs Symptoms in 239,876 Routine Health Check-ups

Context
Restless Legs Syndrome (RLS) is a common neurological condition impairing sleep and quality of life. In primary care, prevalence estimates often rely on standardized questionnaires, yet less is known about symptom identification during routine consultations without systematic screening.
Objectives
To assess the frequency of spontaneously reported restless legs symptoms during routine health check-ups in a primary care setting, and to explore associated demographic, sleep-related, biological and clinical factors.
Methods
We conducted a retrospective observational study based on 239,876 adult health check-ups performed between 2004 and 2022 in a French primary care prevention centre. Restless legs symptoms were identified solely through spontaneous patient complaints recorded during the clinical interview and coded as present or absent. Analyses were stratified by age and sex. Associations were examined with poor sleep complaints, Epworth Sleepiness Scale (ESS ; categories <7, 7–13, ≥14), haemoglobin level and cervical pain. A multivariable logistic regression model included sex, age, poor sleep, haemoglobin, cervical pain and ESS category.
Results
Out of 239,876 exams, only 581 patients reported symptoms (frequency : 0.24%). The "typical" case was a woman (68% of cases, ratio 2.1:1) between 35 and 65 years old.
Key findings : Risk factors : Female sex (OR=3.0), aging (OR=2.0), and poor sleep (OR=1.6). The "Spine" connection : We found a clear cranio-caudal gradient. The risk was high for cervical pain (OR=2.1) but disappeared for low back pain (OR=1.3, NS). Sleepiness : Higher ESS scores were directly linked to more complaints.
Discussion
The observed frequency (0.24%) is markedly lower than the 2–10% usually reported in the literature, indicating substantial under-recognition of RLS in routine primary care when relying solely on spontaneous symptom reporting. Despite this, associated factors align with known clinical characteristics of RLS. Improved recognition is clinically relevant, particularly in light of emerging evidence suggesting a possible association between RLS and increased cardiovascular risk.
Conclusion
Restless legs symptoms are rarely identified during routine primary care assessments based on spontaneous complaints alone. Simple and systematic screening in patients presenting with sleep complaints or chronic pain may improve earlier recognition of RLS and facilitate appropriate management of associated comorbidities.