In Reply: In response to Dr Genever, our inclusion criteria were selected to reflect contemporary thinking at the time we organized the study; 1 criterion was absence of dementia. Our study was not intended to directly assess whether dementia is a contraindication to deep brain stimulation, and we incorporated multiple cognitive screening procedures in an effort to exclude patients with clear evidence of dementia. Patients were excluded if they had an MMSE score of 24 or less but also underwent an extensive baseline neurocognitive test battery that included the Mattis Dementia Rating Scale. Patients were excluded from randomization if their Mattis Dementia Rating Scale score was 2 SD or more below the mean in comparison with healthy age-matched peers. Seven patients who met inclusion criteria based on MMSE were excluded based on these or other indications of more pronounced cognitive-behavioral impairment suggesting dementia.
Weaver FM, Rothlind J, Stern M. Deep Brain Stimulation for Patients With Advanced Parkinson Disease—Reply. JAMA. 2009;301(19):1985-1986. doi:10.1001/jama.2009.648