John R. Wherrett, MD, PhD, FRCPC, Department of Medicine (Neurology), Toronto Western Hospital and University of Toronto, Toronto, ON.

Contemporary technologies, including digital imaging of the brain during life and quantative microscopy (unbiased stereology) for estimating histological features postmortem, have resulted in important new knowledge about changes in the brain that accompany healthy aging, including evidence that grey matter atrophies with an anterior-posterior gradient. Neurons shrink but numbers are preserved; however, there is moderate reduction in dendritic spines and in synapses that have altered function. This is to be interpreted in the light of evidence for neurogenesis continuing into late life. White matter volume increases into maturity, but in aging there is a marked reduction due mostly to a loss of small myelinated fibres. Cell inclusions characteristic of neurodegenerative disease are commonly found postmortem in the healthy aged.
Key words: brain, aging, morphometry, imaging.

AM Johnson, PhD, Assistant Professor, School of Communication Sciences and Disorders, the University of Western Ontario, London, ON.
SG Adams, PhD, Associate Professor, School of Communication Sciences and Disorders, the University of Western Ontario, London, ON.

In addition to its widely recognized effects on gait, posture, balance, and upper limb coordination, Parkinson’s disease (PD) can have a profound effect on speech and voice, within a cluster of speech characteristics termed hypokinetic dysarthria. Although dopaminergic therapy produces significant benefits in the early stages of PD, speech symptoms may show selective resistance to pharmaceutical therapy in patients with a disease history of more than 10 years. This article discusses the pathophysiology of PD as it relates to speech disorders and considers nonpharmaceutical therapeutic options for hypokinetic dysarthria.
Key words: Parkinson’s disease, speech pathology, dysarthria, treatment.

Rajneesh Calton, MD, FACC, Division of Cardiac Electrophysiology, University Health Network, Toronto General Hospital, Toronto, ON.
Vijay Chauhan, MD, FRCPC, Division of Cardiac Electrophysiology, University Health Network, Toronto General Hospital, Toronto, ON.
Kumaraswamy Nanthakumar, MD, FRCPC, Division of Cardiac Electrophysiology, University Health Network, Toronto General Hospital, Toronto, ON.

Atrial fibrillation (AF) is the most common clinically significant cardiac arrhythmia worldwide, with an estimated prevalence of 0.4% in the general population. Despite recent advances in our understanding of the mechanism and consequences of AF, effective therapy for patients with AF remains difficult in many patients. Antiarrhythmic drug therapy includes control of ventricular rate as well as restoration and maintenance of sinus rhythm. The risks and benefits of each treatment modality must be assessed according to each individual patient’s circumstances. Anticoagulation for stroke prevention is a critical component of AF management that is currently underprescribed. Anticoagulation with vitamin K antagonists, such as warfarin, remains the treatment of choice for preventing stroke and cardio embolism. The oral direct thrombin inhibitor ximelagatran has the potential to favourably influence the management of patients with AF by maximizing the potential of anticoagulation for stroke prevention.
Key words: atrial fibrillation, anticoagulation, rate control, warfarin, ximelagatran, antiarrhythmic.

Ging-Yuek Robin Hsiung, MD, MHSc, FRCPC, Assistant Professor, Division of Neurology, Department of Medicine, UBC Clinic for Alzheimer Disease & Related Dementias, University of British Columbia, Vancouver, BC.

Dementia care represents a significant burden to our society. Although we are still far from any cure for dementia, there are several medications available for symptomatic management of Alzheimer’s disease and vascular dementia. These agents not only improve the cognitive and behavioural symptoms of dementia but may also help maintain patients’ functional independence and lessen caregiver stress. There are also a number of clinical trials currently in place to investigate new agents for treatment of Alzheimer’s disease. This article reviews the current medications available for Alzheimer’s disease and vascular dementia, as well as a number of promising agents that are under investigation.
Key words: Alzheimer’s disease, vascular dementia, cholinesterase inhibitors, donepezil, galantamine, rivastigmine, memantine.

Gabriel Gregoratos, MD, FACC, Clinical Professor, Emeritus, Division of Cardiology, University of California, San Francisco, CA, USA.

Syncope accounts for six percent of all hospital patient admissions and is a common and frequently debilitating symptom in older patients. The common causes of syncope in older populations are orthostasis, cardiac arrhythmias, neurocardiogenic syncope, and carotid sinus hypersensitivity. The cause of syncope can usually be deduced or suspected by simple initial clinical evaluation. Arrhythmic syncope will usually require ambulatory ECG monitoring or possibly an implantable loop recorder for precise diagnosis. Neurocardiogenic syncope can be frequently confirmed with a tilt-table test and carotid sinus hypersensitivity by careful carotid sinus stimulation during ECG rhythm monitoring. A permanent pacemaker is indicated for all types of symptomatic bradycardia whether complete AV block, severe sinus bradycardia, or the bradycardia-tachycardia syndrome in patients with sinus node dysfunction. Pacemaker therapy is also indicated to prevent certain pause-dependent tachyarrhythmias, although its role in atrial fibrillation remains controversial unless there is clear evidence of bradycardia-tachycardia sequence. Pacing therapy can also effectively treat syncope due to carotid sinus hypersensitivity when the cardioinhibitory component (heart rate slowing) predominates. The role of pacing therapy for neurocardiogenic (vasovagal) syncope remains controversial.
Key words: syncope, pacemakers, neurocardiogenic, carotid sinus, bradycardia-tachycardia.

Martin Pinquart, PhD, Associate Professor, Department of Developmental Psychology and Center for Applied Developmental Science, Friedrich Schiller University, Jena, Germany.
Silvia Sörensen, PhD, Assistant Professor, Department of Psychiatry, University of Rochester, Rochester, NY, USA.

Due to the aging of society and the increase in ethnic diversity, there is a growing interest in the needs of ethnically diverse caregivers for older adults. Based on a recent meta-analysis, this article outlines ethnic differences in caregiving stressors, available social resources, and caregiver health. We offer suggestions on how to consider ethnic differences in the planning and implementation of caregiver interventions.
Key words: family caregivers, ethnicity, stress, burden, depression.

Roger Y. Wong, MD, FACP, FRCPC, Division of Geriatric Medicine, Department of Medicine, University of British Columbia, Vancouver, BC.

Mobility impairment is a common cause of disability in older persons. The etiology is often multiple, with medical illnesses that affect the musculoskeletal, neurologic, cardiac, and/or respiratory systems superimposed on aging-related changes in gait and balance. A detailed history on the onset, duration, nature, and course of the mobility impairment is helpful. Physical examination should focus on direct observation of gait and balance, while performance- based tests can quantify the abnormalities. Simple tests for assessing walking speed, endurance, and balance are available for both outpatient and inpatient settings. The management of mobility impairment requires a multifaceted interdisciplinary approach.
Key words: mobility, gait and balance, impairment, assessment, walk tests.

Elliott M. Kanner, MD, PhD, Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University College of Physicians and Surgeons, New York, NY, USA.
James C. Tsai, MD, Associate Professor and Director, Glaucoma Division, Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University College of Physicians and Surgeons, New York, NY, USA.

Glaucoma is a sight-threatening, progressive optic neuropathy whose incidence increases with age. Currently, the only proven treatment for glaucoma is the reduction of intraocular pressure (IOP). As medical treatment has become safer and diagnostic modalities have become more sensitive, it has become possible to detect and treat glaucoma earlier. This means that with more aggressive screening and treatment, a common cause of irreversible blindness can be prevented. As more patients are treated earlier, it is important not only for ophthalmologists but also for primary care physicians to be aware of the barriers to adherence and possible interactions and side effects of glaucoma medications. Parallels between glaucoma and other neurodegenerative disease are stimulating new approaches to therapy beyond IOP control, targeted directly at the prevention of axonal loss.
Key words: glaucoma, intraocular pressure, medications, neuroprotection, retinal ganglion cell.

Paul J. Christo, MD, Assistant Professor; Director, Pain Treatment Center & Multidisciplinary Pain Fellowship, Division of Pain Medicine, Department of Anesthesiology and Critical Care, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Greg Hobelmann, MD, Postdoctoral Fellow, Division of Pain Medicine, Department of Anesthesiology and Critical Care, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Amit Sharma, MD, Postdoctoral Fellow, Division of Pain Medicine, Department of Anesthesiology and Critical Care, The Johns Hopkins University School of Medicine, Baltimore, MD, USA. *Current Address: Assistant Professor, College of Physicians & Surgeons of Columbia University, New York, NY.

Steven E. Lo, MD, The Neurological Institute, Columbia University Medical Center, New York, NY, USA.
Steven J. Frucht, MD, The Neurological Institute, Columbia University Medical Center, New York, NY, USA.

Parkinson’s disease (PD) is a neurodegenerative disorder that can significantly impact older patients’ quality of life. Although there are many pharmacologic options to treat PD, the clinician needs to know the indications and potential adverse effects of new medications in the older patient population. Carbidopa/levodopa remains the gold standard for treatment, and new formulations and levodopa-extenders fill specific niches. This article reviews the pros and cons of these medications in older PD patients, and demonstrates therapeutic strategies through case presentations.
Key words: Parkinson’s disease, treatment, levodopa, COMT inhibitor, aging.