Elderly population defined

Chronological Age. Because of this wide variation within the elderly population, it is difficult to devise a catch-all age one must attain to be considered elderly. Within the government, there also appears to be a problem of consistently defining this age group. Table 2, which lists a variety of federally funded programs and their corresponding age criteria, illustrates this point quite well. Table 3 lists what seems to be one of the better classification systems that has been devised [5], As well as being the system currently used by the U.S. Bureau of the Census, it is often implemented in studies that specifically deal with elderly populations [6,7]. 

Increasingly, our society is composed of greater numbers of elderly individuals, defined as 65 and older. Currently, the elderly constitute nearly 20 percent of the population. Consequently, psychotherapists are faced with diagnostic and treatment dilemmas specific to this population. Presented here are patterns and risks of medication use in the elderly (figure B-2) and age-specific factors contributing to adverse effects (figure B-3). Also discussed are recommended adjustments for use of psychotropics in the geriatric patient. 

Sarcopenia is defined as an involuntary loss of skeletal muscle mass and function that occnrs with advancing age. It has been associated with muscle weakness resulting in an increased prevalence of falls, loss of function and independence, and higher morbidity. As the elderly population increases, sarcopenia and its resulting disability will become increasingly important. There are 39 million Americans over the age of 65, with an expected increase of 6 million in the next 10 years. 

Psychotic symptoms in late life (greater than 65 years of age) are generally a result of an ongoing chronic illness carried over from younger life however, a small percentage of patients develop psychotic symptoms de novo, defined as late-life schizophrenia. The 6-month prevalence rate of schizophrenia in the elderly is around 1%. However, other illnesses presenting with psychotic symptoms are common in this population, as approximately one-third of patients with Alzheimer s disease, Parkinson s disease, and vascular dementia experience psychotic symptoms. The majority of data for antipsychotic use in the elderly comes from experience treating these other disease states. 

There are of course many mathematically complex ways to perform a risk assessment, but first key questions about the biological data must be resolved. The most sensitive endpoint must be defined along with relevant toxicity and dose-response data. A standard risk assessment approach that is often used is the so-called divide by 10 rule . Dividing the dose by 10 applies a safety factor to ensure that even the most sensitive individuals are protected. Animal studies are typically used to establish a dose-response curve and the most sensitive endpoint. From the dose-response curve a NOAEL dose or no observed adverse effect level is derived. This is the dose at which there appears to be no adverse effects in the animal studies at a particular endpoint, which could be cancer, liver damage, or a neuro-behavioral effect. This dose is then divided by 10 if the animal data are in any way thought to be inadequate. For example, there may be a great deal of variability, or there were adverse effects at the lowest dose, or there were only tests of short-term exposure to the chemical. An additional factor of 10 is used when extrapolating from animals to humans. Last, a factor of 10 is used to account for variability in the human population or to account for sensitive individuals such as children or the elderly. The final number is the reference dose (RfD) or acceptable daily intake (ADI). This process is summarized below. 

In a large prospective population sample, primarily a cancer research project (CLUE study), Haroun [42] noted that smoking accounted for no less than 30% of the "attributable risk" of chronic kidney disease (CKD), defined as serum creatinine > 2 mg/ dl, and this was particularly true in the elderly. 

A chronic condition, defined as an illness or impairment that caimot he cured, is often the cause of disahihty in the elderly. The older population compared with younger persons is more affected by chronic conditions for several reasons (1) the types of chronic conditions common among older persons tend to he more disabling (e.g., arthritis, heart disease), (2) the conditions become more severe with aging, and (3) several conditions are likely to be present. ... 

The geriatric population is arbitrarily defined as comprising subjects 65 years or older. The older the population likely to use the drug, the more important it is to include the older age range, 75 years and older. For drugs used to treat diseases not unique to, but present in, the elderly, a minimum of 100 subjects usually would allow detection of clinically important differences between the elderly and younger subjects with respect to efficacy as well as adverse reactions. 

Observations that hermaphroditic children who ultimately turned male were genetically deficient in 5a-reductase led to the idea that competitive inhibitors of this enzyme would greatly decrease levels of dihydrotestosterone. This might in turn reduce the oversize gland in the common affliction of elderly men called benign prostatic hyperplasia (BPH), and avoid the usual therapy—surgery. The synthetic 4-azasteroid finasteride (Proscar) was introduced (1992) to treat BPH in a defined patient population. 

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