Predictors of multi-domain cognitive decline following DBS for treatment of Parkinson's disease.

BACKGROUND: Statistically and clinically significant cognitive declines are observed in a small subset of individuals with Parkinson's Disease (PD) following treatment with Deep Brain Stimulation (DBS). OBJECTIVES: We examine the association between multi-domain cognitive decline (MCD) and demographic and baseline clinical variables and the incidence of serious adverse events (SAE) arising within a six-month interval following DBS for PD. METHOD: Study participants with PD who displayed MCD at 6-month follow-up evaluation after DBS (n = 18) were contrasted with individuals with PD from the same study who did not show cognitive decline after DBS (n = 146). Logistic regression analyses were employed to assess relationship between predictors, including age (>70 years old), pre-DBS cognitive screening test performance, SAE, and MCD. MCD+ and MCD-groups were also compared on other baseline clinical and demographic variables. RESULTS: MCD showed modest association with older age and lower baseline neurocognitive screening performance, whereas the groups did not differ on most other baseline clinical and demographic variables. SAEs during the study interval were the most robust predictor of MCD in the DBS group. A variety of SAEs were documented in study participants experiencing MCD after DBS surgery, including, but not limited to, infections and small intracranial hemorrhages. CONCLUSIONS: Older age and lower baseline cognition measured prior to treatment are associated with MCD measured at six-months after DBS. SAE occurring following DBS surgery are also predictive of MCD. These predictors may reflect aspects of "frailty" in advanced PD. Risk factors for SAE warrant careful consideration in clinical trials.

A Prospective, Randomized, Masked, and Placebo-Controlled Efficacy Study of Intraarticular Allogeneic Adipose Stem Cells for the Treatment of Osteoarthritis in Dogs.

Osteoarthritis (OA) is a degenerative joint disease with a high prevalence in dogs. Mesenchymal stem cells (MSCs) have been used to treat humans, dogs, and horses with OA. This report describes a prospective, randomized, blinded, and placebo-controlled clinical efficacy study of intraarticular allogeneic adipose stem cells for the treatment of dogs with OA. Health assessments and measurements of pain and activity impairment were performed at baseline and at selected time points through day 60. The primary outcome variable was the owner Client-Specific Outcome Measurement (CSOM) and secondary measures included veterinary pain on manipulation, veterinary global score, and owner global score. The dogs were treated with either a saline placebo or a single dose of allogeneic adipose-derived MSCs in either one or two joints. Seventy-four dogs were statistically analyzed for efficacy outcomes. Success in the primary outcome variable, CSOM, was statistically improved in the treated dogs compared to the placebo dogs (79.2 versus 55.4%, p = 0.029). The veterinary pain on manipulation score (92.8 versus 50.2%, p = 0.017) and the veterinary global score (86.9 versus 30.8%, p = 0.009) were both statistically improved in treated dogs compared to placebo. There was no detected significant difference between treated and placebo dogs in the incidence of adverse events or negative health findings. Allogeneic adipose-derived stem cell treatment was shown to be efficacious compared to placebo. This large study of dogs also provides valuable animal clinical safety and efficacy outcome data to our colleagues developing human stem cell therapy.

Neuropsychological changes following deep brain stimulation surgery for Parkinson's disease: comparisons of treatment at pallidal and subthalamic targets versus best medical therapy.

BACKGROUND: Deep brain stimulation (DBS) improves motor symptoms in Parkinson's disease (PD), but questions remain regarding neuropsychological decrements sometimes associated with this treatment, including rates of statistically and clinically meaningful change, and whether there are differences in outcome related to surgical target. METHODS: Neuropsychological functioning was assessed in patients with Parkinson's disease (PD) at baseline and after 6 months in a prospective, randomised, controlled study comparing best medical therapy (BMT, n=116) and bilateral deep brain stimulation (DBS, n=164) at either the subthalamic nucleus (STN, n=84) or globus pallidus interna (GPi, n=80), using standardised neuropsychological tests. Measures of functional outcomes were also administered. RESULTS: Comparison of the two DBS targets revealed few significant group differences. STN DBS was associated with greater mean reductions on some measures of processing speed, only one of which was statistically significant in comparison with stimulation of GPi. GPi DBS was associated with lower mean performance on one measure of learning and memory that requires mental control and cognitive flexibility. Compared to the group receiving BMT, the combined DBS group had significantly greater mean reductions at 6-month follow-up in performance on multiple measures of processing speed and working memory. After calculating thresholds for statistically reliable change from data obtained from the BMT group, the combined DBS group also displayed higher rates of decline in neuropsychological test performance. Among study completers, 18 (11%) study participants receiving DBS displayed reliable decline by multiple indicators in two or more cognitive domains, a significantly higher rate than in the BMT group (3%). This multi-domain cognitive decline was associated with less beneficial change in subjective ratings of everyday functioning and quality of life (QOL). The multi-domain cognitive decline group continued to function at a lower level at 24-month follow-up. CONCLUSIONS: In those with PD, the likelihood of significant decline in neuropsychological functioning increases with DBS, affecting a small minority of patients who also appear to respond less optimally to DBS by other indicators of QOL. TRIAL REGISTRATION NUMBER: NCT00056563 and NCT01076452.