Summary

Geriatricians have tentatively identified a "frailty syndrome", and have elaborated a definition, a diagnostic approach, a determination of causes, and possible treatments.

Introduction

As the over-70s and over-80s become the over-80s and over-90s, we come to recognize the general condition of frailty much more often. It's distressing when a near and dear relative is suddenly seen to be frail, without an obvious cause except "old age". Geriatricians are struggling with the definition of a "frailty syndrome". After all, if it's a distinct syndrome, maybe one can treat it? University of Arizona scientists have reviewed what's known of the topic in the American Journal of Medicine. Here's a capsule of their paper, and some conclusions of my own.

A Definition

Frailty is identified by slowly decreasing reserves in multiple organ systems. There is loss of muscle mass (called sarcopenia), abnormal function in inflammatory and hormonal systems, and poor energy regulation. This may all be covered by the description "excess demand imposed on reduced capacity". Once frailty is established, there is often a rapid downward spiral towards death.

How Common is Frailty?

Only 3% to 7% of 65- to 75-year-olds are frail, but this proportion reaches a third for people in their 90s. About 7% of the frail elderly have no accompanying illness, and one in four have only one coexistent disease. But frailty may occur after an acute event or as the end stage of a chronic condition such as atherosclerosis, infection, cancer, and depression.

It's important to differentiate frailty from disability. The latter doesn't involve multiple organ systems; in fact, only 28% of disabled people (as measured by the activities of daily living [ADL] and instrumental activities of daily living [IADL] scores) are frail.

There are several phases of frailty. In the first stage, also called pre-frailty, the subject has fewer than 3 of the characteristic signs of frailty (see below). Pre-frail persons are more likely than others to develop full-blown frailty; they are more likely to fall, be institutionalized, or die, but not as likely to experience these risks than frail elderly persons. In the final stages of frailty, there is 'failure to thrive' - functional decline, progressive apathy, decreased appetite, and death.

In general, frailty is more common in women. And the frail have a significantly increased risk of cardiovascular disease, high blood pressure, and cancer.

A Working Diagnosis

A diagnosis of frailty requires 3 of the following 5 characteristics:

• Decreased walk time (15-foot walk test)
• Decreased grip strength (dynamometer)
• Decreased physical activity (Minnesota Leisure Time Activity Questionnaire)
• Exhaustion (Center for Epidemiologic Studies Depression Scale)
• Weight loss (over 10 pounds or 5% loss in the last year)

Of course, other diseases must be excluded. Congestive heart failure, polymyalgia rheumatica, Parkinson's disease, rheumatoid arthritis, occult cancer, and infection come to mind.

Frailty is seen more often in women, African Americans, those with lower income and lower education levels, chronic illness, depression, and disability. Increased blood C-reactive protein (CRP - a marker for inflammation) and fibrinogen are seen, and sometimes impaired glucose tolerance; DHEA, a precursor of testosterone, is often significantly lower than normal. One study has shown that 25(OH)-vitamin D levels are more than halved.

The Cause of Frailty

Speculation is rampant, but facts are few. Data from the Women's Health Initiative Study suggest that obesity, anorexia (loss of appetite), smoking, and depression may lead to frailty, but other studies deny a relationship between frailty - but not mortality - and smoking, heavy drinking, inactivity, and depression.

Researchers are looking at the possibility that cellular changes may be responsible or even changes at the molecular level. These would be mechanisms relating to aging: oxidative stress, telomere shortening, gene expression changes, or cellular senescence. But it remains obvious that the cause of frailty is at present obscure.

Treatment Approaches

Initially, any medical conditions that may cause frailty must be treated appropriately. Then sarcopenia must be arrested by muscle-strengthening exercises. Frailty markers have been shown to improve after 30 to 60 minutes exercise, 3 times a week, for 3 to 6 months.

Nutritional efforts can be tried. Increased calorie intake has little benefit, but a nutritional program combined with an exercise regimen to increase calorie expenditure by 1000 calories a week has had some success. Appetite stimulants (e.g. megestrol acetate or dronabinol) may be tried, but they have significant side effects. Although hormone levels are often decreased in frailty, no conclusive benefits from hormone replacement (testosterone, DHEA, or growth hormone) have been shown.

My Conclusions

What conclusions can one draw from this review? Not too much, from my personal viewpoint. Frailty seems to be like pornography - it's hard to define, but one knows it when one sees it. The diagnostic testing method is unlikely to be helpful, as there's no specific treatment. The only positive approaches revealed were treating underlying disease processes, exercise, and ensuring adequate nutrition; this is something one can advocate without considering the word 'frailty'.

If you want to learn more about frailty, I can recommend an article by Professor John Morley - it's the first link below.