REN and obstructive sleep apnea syndrome: Now, when a patient with suspected OSA has been prescribed a particular drug for a particular disease over a sustained time, we can confidently impute disease information with an error ranging from 5% (for the disease-drug association between agents acting on the renin-angiotensin system [C09] and arterial hypertension) to 13% (for lipid-modifying agents [C10] and dyslipidemia).