Deep brain stimulation targeting the fornix for mild Alzheimer dementia: design of the ADvance randomized controlled trial

Kathryn B Holroyd,1 Lisa Fosdick,2 Gwenn S Smith,1 Jeannie-Marie Leoutsakos,1 Cynthia A Munro,1 Esther S Oh,1 Kristen E Drake,2 Paul B Rosenberg,1 William S Anderson,1 Stephen Salloway,3–5 J Cara Pendergrass,6 Anna D Burke,7 David A Wolk,8 David F Tang-Wai,9–11 Francisco A Ponce,12 Wael F Asaad,13,14 Marwan N Sabbagh,15 Michael S Okun,16 Gordon Baltuch,17 Kelly D Foote,18 Steven D Targum,2,6 Andres M Lozano,10,11 Constantine G Lyketsos1 1Johns Hopkins University Memory and Alzheimer's Treatment Center, Baltimore, MD, 2Functional Neuromodulation Ltd, Minneapolis, MN, 3Department of Neurology, Butler Hospital, 4Department of Neurology, Rhode Island Hospital, 5Department of Neurology, Warren Alpert Medical School of Brown University, Providence, RI, 6Clintara LLC, Boston, MA, 7Banner Alzheimer's Institute, Phoenix, AZ, 8Penn Memory Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA; 9Department of Neurology, 10Department of Neurosurgery, University of Toronto, 11Division of Neurology, University Health Network Memory Clinic, Toronto, ON, Canada; 12Division of Neurological Surgery, Barrow Neurological Institute, St Joseph's Hospital and Medical Center, Phoenix, AZ, 13Department of Neurosurgery, Rhode Island Hospital, 14Department of Neurosurgery, Warren Alpert Medical School of Brown University, Providence, RI, 15Banner Sun Health Research Institute, Sun City, AZ, 16Center for Movement Disorders and Neurorestoration, Department of Neurology, University of Florida – Gainsville, Gainsville, FL, 17Center for Functional and Restorative Neurosurgery, University of Pennsylvania, Philadelphia, PA, 18Department of Neurosurgery, Center for Movement Disorders and Neurorestoration, University of Florida, Gainsville, FL, USA Background: There are currently few available treatments and no cure for Alzheimer disease (AD), a growing public health burden. Animal models and an open-label human trial have indicated that deep brain stimulation (DBS) of memory circuits may improve symptoms and possibly slow disease progression. The ADvance trial was designed to examine DBS of the fornix as a treatment for mild AD. Methods: ADvance is a randomized, double-blind, placebo-controlled, delayed-start, multicenter clinical trial conducted at six sites in the US and one site in Canada. Eighty-five subjects initially consented to be screened for the trial. Of these, 42 subjects who met inclusion and exclusion criteria were implanted with DBS leads anterior to the columns of the fornix bilaterally. They were randomized 1:1 to DBS “off” or DBS “on” groups for the initial 12 months of follow-up. After 1 year, all subjects will have their devices turned “on” for the remainder of the study. Postimplantation, subjects will return for 13 follow-up visits over 48 months for cognitive and psychiatric assessments, brain imaging (up to 12 months), and safety monitoring. The primary outcome measures include Alzheimer's Disease Assessment Scale – cognitive component (ADAS-cog-13), Clinical Dementia Rating sum of boxes (CDR-SB), and cerebral glucose metabolism measured with positron emission tomography. This report details the study methods, baseline subject characteristics of screened and implanted participants, and screen-to-baseline test–retest reliability of the cognitive outcomes. Results: Implanted subjects had a mean age of 68.2 years, were mostly male (55%), and had baseline mean ADAS-cog-13 and CDR-SB scores of 28.9 (SD, 5.2) and 3.9 (SD, 1.6), respectively. There were no significant differences between screened and implanted or nonimplanted subjects on most demographic or clinical assessments. Implanted subjects had significantly lower (better) ADAS-cog-11 (17.5 vs 21.1) scores, but did not differ on CDR-SB. Scores on the major outcome measures for the trial were consistent at screening and baseline. Conclusion: ADvance was successful in enrolling a substantial group of patients for this novel application of DBS, and the study design is strengthened by rigorous subject selection from seven sites, a double-blind placebo-controlled design, and extensive open-label follow-up. Keywords: deep brain stimulation, Alzheimer disease, fornix, methods, clinical trial

Modeling of Virion Collisions in Cervicovaginal Mucus Reveals Limits on Agglutination as the Protective Mechanism of Secretory Immunoglobulin A

<div><p>Secretory immunoglobulin A (sIgA), a dimeric antibody found in high quantities in the gastrointestinal mucosa, is broadly associated with mucosal immune protection. A distinguishing feature of sIgA is its ability to crosslink pathogens, thereby creating pathogen/sIgA aggregates that are too large to traverse the dense matrix of mucin fibers in mucus layers overlying epithelial cells and consequently reducing infectivity. Here, we use modeling to investigate this mechanism of “immune exclusion” based on sIgA-mediated agglutination, in particular the potential use of sIgA to agglutinate HIV in cervicovaginal mucus (CVM) and prevent HIV transmission. Utilizing reported data on HIV diffusion in CVM and semen, we simulate HIV collision kinetics in physiologically-thick mucus layers–a necessary first step for sIgA-induced aggregation. We find that even at the median HIV load in semen of acutely infected individuals possessing high viral titers, over 99% of HIV virions will penetrate CVM and reach the vaginal epithelium without colliding with another virion. These findings imply that agglutination is unlikely to be the dominant mechanism of sIgA-mediated protection against HIV or other sexually transmitted pathogens. Rather, we surmise that agglutination is most effective against pathogens either present at exceedingly high concentrations or that possess motility mechanisms other than Brownian diffusion that significantly enhance encounter rates.</p></div

The Challenging Pelvic Examination

While there is a large body of evidence on the effectiveness of Pap smears for cervical cancer screening and on screening for cervical gonorrhea and Chlamydia, there is sparse evidence to support other portions of the pelvic examination and little guidance on examination logistics. Maximizing comfort should be the goal; lubrication use and careful speculum selection and insertion can ease this intrusive procedure. This is particularly important in adolescent and menopausal women, sexual minorities, obese women, women with disabilities, and women with a history of trauma or prior instrumentation affecting the genitalia. We review the evidence and provide guidance to minimize physical and psychological discomfort with pelvic examination