I am a 50-year-old man with diabetic neuropathy (nerve damage). Sometimes I get uncomfortable feelings in my legs and an urge to move while I’m resting. Are these symptoms due to nerve damage as a result of diabetes or do I have another condition?
The question here is whether you have symptoms due to diabetic neuropathy or whether you have symptoms that may suggest another condition such as RLS. In cases of long-term diabetes mellitus, damage to the peripheral nerves may cause symptoms of tingling, numbness, burning, and stabbing, generally in a “stocking and glove” distribution. These sensory symptoms are present intermittently or throughout the day, but do not necessarily become worse in the evenings; also, they are generally not relieved by movements. In addition, patients with diabetes mellitus may experience weak-ness of the muscles of the legs, which does not occur in RLS. RLS is thought to be more common in persons with diabetes mellitus than in the general population.
Indeed, several case series have recently shown that RLS occurs more frequently in diabetes patients, particularly in those who develop diabetic neuropathy. The sensory symptoms of patients with primary RLS are characterized by deep, disagreeable, unpleasant, often nonlocalized and nonradiating discomfort accompanied by no objective sensory impairment. In contrast, diabetic peripheral neuropathy patients often show impairment of sensation on objective testing. It is also notable that in about 20 to 25% of patients with primary RLS, there is actual pain rather than intense dis-agreeable feelings. The difficulty in distinguishing between the two situations arises in those patients who are genetically predisposed to develop RLS symptoms: In such a case, the patient may have mixed diabetic neuropathic and RLS sensory symptoms.
As mentioned in Question 4, RLS patients’ complaints should meet all four essential diagnostic criteria. There-fore, it is possible to have both diabetic peripheral neuropathy and RLS. To make the diagnosis in this case, the patient should consult a neurologist who is also a sleep specialist, particularly a neurologist with special interest in RLS.