Liesel-Ann Meusel¹, PhD, Ekaterina Tchistiakova^2,3, BSc, William Yuen^4,5, BSc, Bradley J Macintosh^2,3, PhD, Nicole D Anderson^1,6, PhD, and Carol E Greenwood^4,5, PhD
¹Rotman Research Institute, Baycrest Centre, Toronto, ON. ²HSF Centre for Stroke Recovery, Sunnybrook Research Institute, Toronto, ON. ³Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, ON.
⁴Kunin-Lunenfeld Applied and Evaluative Research Unit, Baycrest Centre, Toronto, ON. ⁵Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON. ⁶Departments of Psychology and Psychiatry, University of Toronto, Toronto, ON.

Abstract
Type 2 diabetes mellitus is increasingly common, and previously unrecognized complications are emerging; namely, cognitive impairment and dementia. The mechanisms that link these factors together are still unknown, but likely result from the interplay of several variables, including vascular change, poor glycemic control, inflammation, and hypothalamic pituitary adrenal overactivity. At present, it is still too early to propose best practices related to the management of diabetes-induced cognitive change. All things considered, however, patients should be aware that proper management of metabolic and vascular complications may minimize the adverse effects of type 2 diabetes on cognitive function and quality of life.
Keywords: type 2 diabetes, cognition, dementia, vascular, metabolic.

Our focus this month is on diabetes and related endocrine disorders such as the metabolic syndrome. It does not take much in the way of insight to recognize that North American society is getting fatter, decade by decade. The rise in obesity and the aging of the population has resulted in a staggering increase in the prevalence of Type II Diabetes Mellitus (DMII). What surprised me this year, however, was seeing evidence of this phenomenon during my trip to China. In the prosperous urban areas of the country there are many people who are overweight. To my eye there was a clear gradient among those using different modes of transportation. Bicycle riders were more slender than drivers of electric scooters, and drivers of cars seemed to be the heaviest. In the less prosperous rural areas, everybody seemed to be quite slim. In the coming decades the absolute numbers of people with DMII in the developing world will be enormous. This epidemic will not remain a North American/Western European phenomenon.

There is an article by Dr. Jeremy Gilbert in this month’s journal entitled “Pharmacological Treatments for Diabetes Among Older Adults: An Update.” With the proliferation of new treatments for DMII this is indeed a timely topic to address, and our CME course is based on this very practical topic. However, treatment is never as desirable as prevention, and the article “Preventing Diabetes and Cardiovascular Disease in Older Adults: Controlling the Metabolic Syndrome Through Lifestyle Interventions” by Dr. Muhammad Firdaus and Dr. Timothy J. Lyons is particularly important. “Preventing Amputations in Older Adults with Diabetes” by Dr. Naven Duggal completes the trio of topics on this month’s focus.

We also have our usual collection of articles on important geriatric topics. Our cardiovascular disease column this month is “Blood Pressure and Survival in the Very Old” by Drs. Kati Juva, Sari Rastas, and Tuula Pirttilä. Our dementia topic this month is “Use of Atypical Antipsychotic Medications in Later Life” by Drs. Tarek Rajji, Benoit H. Mulsant, Hiroyuki Uchida, and David Mamo. In the past few years, real scientific evidence has started to accumulate on how to use these medications in older adults. To round off this issue, we have an informative case study by David Wan and Dr. Shabbir M.H. Alibhai entitled “A Case of Methotrexate-Induced Pancytopenia.”

Enjoy this month’s issue,

Barry Goldlist

A.D. Baines, MD, PhD, FRCPC, Professor, Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON.

This article presents a summary of recent recommendations for the diagnosis and treatment of Type 2 diabetes in the elderly. Onset of nephropathy, neuropathy and retinopathy can be slowed by treatment designed to reach realistic target values for fasting plasma glucose and HbA1c. Therapy also should minimize the dangers of hypoglycemia. Hepatic and renal function must be monitored when selecting drugs and dosages. Significant reductions in renal function may be associated with serum creatinine within the normal reference range. A stepwise approach to therapy beginning with diet and exercise and proceeding to single and multidrug treatment is outlined. The mode of action, advantages, disadvantages and contraindications for five groups of hypoglycemic agents are summarized.
Key words: Type 2 diabetes, diagnosis, stepped treatment, oral drugs, elderly.

David C.W. Lau, MD, PhD, FRCPC, Professor of Medicine, Biochemistry and Molecular Biology; Director, Julia McFarlane Diabetes Research Centre, University of Calgary, Calgary, AB.

As the population ages, the diagnosis of Type 2 diabetes is expected to skyrocket over the next two decades. Diabetes is diagnosed by a fasting venous plasma glucose level of equal to or greater than 7mmol/L or, in the presence of classic symptoms of hyperglycemia, a casual plasma glucose value greater than 11.1mmol/L. Early diagnosis, screening and prevention of diabetes in the elderly will greatly reduce the burden of this serious chronic disease that is associated with increased morbidity and mortality.
Key words: impaired glucose tolerance, diagnosis, screening, prevention, Type 2 diabetes

The Diabetes Epidemic
Diabetes is now reaching epidemic proportions in Canada and the U.

Alexandra Nevin, BSc

Type II diabetes is a complicated, multifactorial disease process characterized by a relative insulin insensitivity leading to prolonged hyperglycemia. In comparison with type I diabetes, which is primarily due to the auto-immune-mediated destruction of the insulin producing beta cells of the pancreas, type II diabetes is the more predominant, generally adult- onset form, which predisposes individuals to pathological complications, and is more amenable to lifestyle modifications.

Senior citizens are the population most susceptible to type II diabetes. The Canadian Heart Health Survey reported that 13.2% of men and 12.0% of women between the ages of 65 and 74 have diabetes. In light of the aging population in Canada, researchers continue to investigate the intertwined role of genetics and the environment in the pathogenesis of type II diabetes in an effort to better understand and, ideally, to devise true preventative therapy measures to combat the disease.

Pathogenesis
Two fundamental defects underlie the pathogenesis of type II diabetes. The primary problem is the development of insulin resistance. In an attempt to compensate for the increased blood glucose load, a period of relative maladaptive hyperinsulinemia occurs.