James L. Silvius, MD, FRCPC, Calgary Health Region, Clinical Associate Professor, Department of Medicine; Head and Chief, Division of Geriatric Medicine, University of Calgary, Calgary, AB.

Depression is common in older adults. This condition is often under-recognized and undertreated in this patient segment as it may present differently than in younger individuals. A number of risk factors for depression have been identified and may help increase recognition. Altered presentations include generalized anxiety/worry, somatisation, presence of a disability gap, subjective but not objective memory complaints, pseudodementia, hopelessness, change in adherence to medical regimens or change in function not otherwise explained. For individuals with dementia syndromes, excess disability may indicate depression. A high index of suspicion, recognition of risk factors, and asking about specific aspects of depression may increase diagnosis.
Key words: depression presentation, risk factors, function, dementia.

Heike A. Bischoff, MD, MPH, Robert B. Brigham, Arthritis and Musculoskeletal Diseases Clinical Research Center, Brigham and Women's Hospital and Division on Aging, Harvard Medical School; Boston, MA, USA.

There is increasing evidence that vitamin D supplementation may improve musculoskeletal function and prevent falls in older persons at risk for vitamin D deficiency. One basic concept appears to be the direct effect of vitamin D on muscle strength. Highly specific receptors for 1,25-dihydroxyvitamin D are expressed in human muscle tissue and it has been suggested that these nuclear receptors promote protein synthesis in the presence of 1,25-dihydroxyvitamin D, eventually leading to improved strength.
Key words: vitamin D, muscle strength, function, elderly, falls.

David Stell, PhD, FRCS(Gen) and William J. Wall, MD, FRCS(C), Department of Surgery and Multi-Organ Transplant Program, London Health Sciences Centre, London, ON.

The process of aging does not produce changes in the liver that can be described as pathological. The major age-related alterations are a reduction in liver mass and a reduction in total blood flow, neither of which interferes with the liver's normal homeostatic functions. In spite of the liver's resilience, however, the aged liver is more vulnerable to injury from toxins, viruses and ischemia, and its capacity to regenerate is slowed. There also is a decline in liver enzymes with aging that affects metabolic clearance of drugs, a finding that has implications for drug dosing in the elderly.
Key words: liver, aging, function, metabolism, injury.