Jane McCusker, MD, DrPH, Professor, Epidemiology and Biostatistics, McGill University; Head, Clinical Epidemiology and Community Studies, St. Mary's Hospital, Montreal, QC.

Nine published studies of the outcomes of delirium with at least six months of follow-up were reviewed. The results indicate that: 1) the symptoms of delirium are more persistent than previously thought; up to 15% of those without dementia and 49% of those with dementia continued to have core symptoms of delirium 12 months after the initial diagnosis; 2) a diagnosis of delirium is an independent predictor of increased mortality for up to three years after diagnosis and; 3) a diagnosis of delirium predicts continued poorer cognitive and physical functioning for up to 12 months after diagnosis.
Key words: delirium, prognosis, dementia, functioning, cognitive status.

James L. Rudolph, MD, SM, Division of Aging, Brigham and Women's Hospital and the Boston VA Geriatric Research, Education, and Clinical Center, Boston, MA.

Edward R. Marcantonio, MD, SM, Hebrew Rehabilitation Center for Aged and Beth Israel Deaconess Medical Center, Boston, MA.

Delirium is a common syndrome in hospitalized older patients that is frequently undiagnosed by health care professionals. This is particularly troubling because delirium is associated with poor outcomes such as increased nursing home placement, nosocomial infections and increased mortality. Criteria for the diagnosis of delirium are validated, reliable and can readily be applied to patients by health care professionals. Solid evidence exists that delirium can be prevented with educated prescribing of medications, practical in-hospital interventions and geriatric consultation.
Key words: delirium, differential diagnosis, prevention, Confusion Assessment Method.

Richard Long, MD, Professor, Department of Medicine, University of Alberta, Edmonton, AB; Chairman, Tuberculosis Committee, Canadian Thoracic Society.

The incidence of tuberculosis increases with age in Canadians. The prevalence of latent tuberculosis infection (LTBI) may also increase with age in Canadians, though information on the age distribution of LTBI is less precise. Chronic inflammatory conditions that currently constitute the major indications for new biologic therapies (tumour necrosis factor inhibitors), such as Crohn's disease and rheumatoid arthritis, often have an older age onset. Biologic therapies have the potential to cause LTBI to progress to active tuberculosis disease. Their use in older Canadians or other populations that may have a higher than average prevalence of LTBI poses a challenge to tuberculosis control.
Key words: tuberculosis, tumour necrosis factor inhibitors, age, rheumatoid arthritis, Crohn's disease.

Philippe L. Bedard, MD, and Feisal A. Adatia, MD, MSc, First Year Ophthalmology Resident; University of Toronto, Toronto, ON.

Many health care professionals use handheld computers to access medical reference information and drug databases at the point of care.¹ There are many specific infectious disease software applications for handheld computers, which combine information regarding specific microbial pathogens and sites of infections with antimicrobial databases and treatment guidelines. Infectious disease software may minimize medication prescription errors and promote more rational use of antimicrobials. This article briefly reviews the salient features of five popular infectious disease applications.

ePocrates ID
ePocrates ID is available with ePocrates Rx Pro, the purchase-based suite which includes the popular handheld drug database, ePocrates Rx. Users can search by location, bug or drug. ePocrates ID provides a numbered list of recommended antimicrobial regimens for both empiric and specific pathogen-based therapy. For each antimicrobial, users can tap on a hyperlink to be connected with ePocrates Rx for more detailed drug monographs. ePocrates ID offers the simplest and most intuitive interface of any available infectious disease handheld application. Busy clinicians can quickly find treatment recommendations and a wide range of well-organized antimicrobial information at the point of care. However, users should be aware that the manufacturer of ePocrates has the ability to track how information is accessed on ePocrates ID.² Another drawback is that ePocrates cannot be run from an expansion memory card. ePocrates Rx Pro is expensive and users must renew their subscription annually. Unlike the core drug database in ePocrates Rx, ePocrates ID is not automatically updated with each hotsync operation, although users can download quarterly updates.

The Sanford 2003 Guide to Antimicrobial Therapy
The Sanford Guide is the handheld version of the popular paper-based infectious disease handbook. The opening screen of the handheld version is split into a "rapid reference" section of 17 commonly used tables and a searchable alphabetical index. The Sanford Guide provides the most detailed coverage of antimicrobial spectra, adverse medication effects and drug interactions and the most extensive literature references. However, unlike other applications, the information in the Sanford Guide is not organized by individual drug monographs, making it difficult to find information about a particular antimicrobial or clinical infection quickly. The search feature in the Sanford Guide is also cumbersome, as scroll bars must be used extensively to find information.

Johns Hopkins Division of Infectious Diseases Antibiotic Guide
Information in this guide may be searched through three side tabs entitled diagnosis, pathogen or antibiotic. Of the reviewed programs, this is the only one which is free and that automatically updates when a handheld syncs with a desktop computer. While being quite comprehensive and having undergone vigorous review for accuracy, this program does not provide any pediatric dosing. As well, drug monographs cannot be accessed through diagnosis or pathogen tabs, adding time required to search for drug details.

The 5-Minute Infectious Diseases Consult
This program is one of the extensive catalogues of medical reference books available from Skyscape. For users of other Skyscape references, the link feature allowing cross-referencing of databases is an attractive benefit. There are four indices that can be searched: Main Index, Microorganisms, Medication Index and Table of Contents. The Main Index is organized into basics, clinical manifestations, diagnosis, treatment, follow-up and selected readings. Perhaps the best feature of this program is its speed and ease of navigation. It is the most expensive of the reviewed databases and provides less drug monograph information than the other alternatives.

Infectious Diseases and Antimicrobials Notes
This program is formatted to run in iSilo, an e-book reader. It has the following sections: antimicrobial spectra index, prophylactic therapy, normal flora, organisms and treatment, infectious disease and treatment and antimicrobial treatment. This program has several attractive features. Its prophylactic therapy section provides details on prevention of infection with chemotherapy and provides surgical antibiotic prophylaxis notes. Its inclusion of a normal flora section is also quite educational. However, it requires extensive scrolling and lacks sidebar tabs seen in other applications. Furthermore, it does not disclose author information or provide references for its citations.

Conclusion
There is a variety of alternatives for users in search of an infectious disease reference for their handheld computers. ePocrates ID and Johns Hopkins Division of Infectious Diseases Antibiotic Guide provide the most concise and easily navigable treatment guidelines for particular clinical scenarios. The Sanford 2003 Guide to Antimicrobial Therapy may be most appropriate for specialists well acquainted with the paper-based version of the guide. The 5-Minute Infectious Diseases Consult offers the most extensive diagnostic information and can be linked with other Skyscape applications. Finally, the Infectious Diseases and Antimicrobials Notes may appeal to those in search of information regarding microbial flora and antimicrobial prophylaxis.

References

1. Adatia FA and Bedard PL. "Palm reading": 1. Handheld hardware and operating systems. CMAJ 2002;167:775-80.
2. Adatia FA and Bedard PL. "Palm reading": 2. Handheld software for physicians. CMAJ 2003;168:727-34.
3. Miller SM, Beattie MM, Butt AA. Personal digital assistant infectious diseases applications for health care professionals. Clin Infect Dis 2003;36:1018-29.

Jonathan M. Flacker, MD, Division of Geriatric Medicine and Gerontology, Emory University School of Medicine, Atlanta, GA, USA.

The term "Geriatric Syndrome" is commonly used but ill defined. In publications, authors claim that all sorts of conditions are a "Geriatric Syndrome", including, but not limited to, delirium,¹ dementia,¹ depression,² dizziness,³ emesis,⁴ falls,¹ gait disorders,¹ hearing loss,¹ insomnia,¹ urinary incontinence,¹ language disorders,¹ functional dependence,⁵ lower extremity problems,⁶ oral and dental problems,⁶ malnutrition,¹ osteoporosis,¹ pain,¹ pressure ulcers,¹ silent angina pectoris,⁷ sexual dysfunction,⁶ syncope⁶ and vision loss.¹ Can this be possible? Can any condition commonly encountered in older adults be a "Geriatric Syndrome"?

The Origins of "Syndrome"
The word syndrome seems to have appeared in an English translation of Galen in about 1541.⁸ Derived from the Greek roots "syn" (meaning "together") and "dromos" (meaning "a running"), this term generally refers to "a concurrence or running together of constant patterns of abnormal signs or symptoms".

John Wherrett, MD, FRCPC, PhD, Division of Neurology, Toronto Western Hospital and the University of Toronto, Toronto, ON.

This commentary addresses current views about the interaction of vascular disorders and Alzheimer disease, including vascular pathologies that may be intrinsic to the Alzheimer process as identified through demonstration of amyloid plaques and neurofibrillary tangles. The common cerebrovascular pathologies accompanying aging, mainly atherosclerosis and arteriosclerosis, will coincide in varying proportions with the Alzheimer pathology, also a concomitant to aging. Because interventions are available to modify both risks and complications of these vasculopathies, an important goal of dementia research is to develop means to characterize the contribution of cerebrovascular disease in Alzheimer and other dementias. Realization of this goal is confounded by the recognition that Alzheimer pathology, usually considered a parenchymal process, involves important vascular changes.
Key words: Alzheimer disease, dementia, cerebrovascular, pathology, imaging.

Jagdish Butany, MBBS, MS, FRCPC, Departments of Pathology, Toronto General Hospital, University Health Network and University of Toronto, Toronto, ON.
Manmeet S. Ahluwalia, MBBS and Vidhya Nair, MBBS, MD, Departments of Pathology, Toronto General Hospital, Toronto, ON.
Christopher Feindel, MD, FRCPC, Cardiovascular Surgery, Toronto General Hospital, University Health Network and University of Toronto, Toronto, ON.

Valvular heart disease is a common cardiac problem. There are many age-associated changes that can occur in otherwise healthy heart valves. These commonly develop in the aortic valve and, to a lesser extent, in the mitral valve. In both cases there is fibrosis and thickening of the tissues with the deposition of calcium salts in the aortic valve cusps and in the annulus of the mitral valve. These changes can contribute to progressive secondary changes in the heart (left ventricle and left atrium), which can be associated with significant morbidity related to complications of valvular disease, such as congestive heart failure, infective endocarditis and sudden death.
Key words: heart valves, age-related changes, calcified aortic valve, mitral annular calcification.

K.H.O. Deane, BSc, PhD and C.E. Clarke, BSc, MD, FRCP, Department of Neurosciences, The University of Birmingham and City Hospital, Birmingham, UK.

Many clinicians, therapists and patients support the use of rehabilitation in the treatment of Parkinson's disease. However, systematic reviews reveal a lack of conclusive evidence to support the use of common forms of rehabilitation therapy in this movement disorder. Lack of evidence of efficacy is not proof of lack of effect. Large pragmatic randomized controlled trials are required to determine the effectiveness and safety of rehabilitation therapies for people with Parkinson's disease.
Key words: Parkinson's disease, occupational therapy, physiotherapy, speech therapy, rehabilitation.

Lona Mody, MD, University of Michigan Medical School, Division of Geriatric Medicine; Geriatric Research Education and Clinical Center, Ann Arbor VA Healthcare System, Ann Arbor, MI, USA.

Skin and soft tissue infections are frequent in older adults residing in both community and nursing homes. Common skin and soft tissue infections include bacterial infections such as cellulitis, erysipelas and necrotizing fasciitis, chronic wound infections, fungal infections such as intertrigo and viral infections like herpes zoster. Early diagnosis is the key to optimal management. Most of these infections can be treated on an outpatient basis and in nursing homes; however, serious infections may require hospitalization especially in frail older adults with a high comorbidity load. This review focuses on clinical manifestations and treatment options for common skin and soft tissue infections in older adults.
Key words: skin infections, cellulitis, necrotizing fasciitis, pressure ulcer, viral infection.

I. W. Fong, MB, BS, FRCPC, Department of Medicine, Division of Infectious Diseases, University of Toronto, St. Michael's Hospital, Toronto, ON.

Atherosclerosis and its vascular complications are the leading causes of death in older people in developed countries. There are accumulating, albeit conflicting, data suggesting that infections, particularly Chlamydia pneumoniae, may play a role in atherogenesis and vascular events. Although prospective epidemiological and clinical studies have provided conflicting results, pathological studies have confirmed the association of C. pneumoniae with atherosclerotic disease. Moreover, many in vitro studies on biological mechanisms and studies in animal models have largely supported a plausible role of infections in atherogenesis. These data suggest that infections, especially C. pneumoniae, may be involved in the initiation and acceleration of atherosclerosis and potentially could lead to acute ischemic events by influencing plaque stability and coagulation.
Key words: atherosclerosis, Chlamydia pneumoniae, infections, older people.