Central Poststroke Pain Can Occur With Normal Sensation

OBJECTIVE:In view of the paucity of studies on central poststroke pain (CPSP), in this hospital-based prospective study, we evaluated the frequency, the spectrum, imaging, and quantitative sensory testing in a cohort of stroke patients with CPSP. METHODS:Stroke patients who developed CPSP at onset or during follow-up were included. Patients were subjected to clinical evaluation and sensory testing. The severity of stroke was defined by the Modified Rankin Scale and disability by the Barthel Index. Quantitative sensory testing included monofilament testing and evaluation for static and dynamic mechanical allodynia, punctuate hyperalgesia, temporal summation, cold allodynia, and cold hyperalgesia. Sleep, anxiety, and depression were also evaluated. Patients were treated with pregabalin 150 to 600 mg/d and good response was defined as >50% improvement in the VAS score. CPSP symptoms were correlated with demographic information, sensory findings, and imaging findings. RESULTS:A total of 319 patients with stroke were evaluated. CPSP occurred in 66 (20.7%) of them. The median age of the CPSP patients was 55 years (range, 25 to 80 y). About 31.8% patients were female. The onset, the duration, and the distribution of pain were variable. The severity of symptoms did not correlate with demographic variables and the site of lesion. Spinothalamic sensations were normal in 42.3% patients. On treatment with pregabalin (150 to 600 mg), half of the patients had a good response. DISCUSSION:CPSP was present in 20.7% of the stroke patients. Spinothalamic tract dysfunction may not be necessary for the development of CPSP, and it can also be seen with normal spinothalamic sensation. The location of the stroke, its type and quality, and the severity of CPSP were not related.