INTRODUCTION: THE AGING OF AIDS

In New Jersey and nationwide, public health officials have documented a dramatic increase in the number and proportion of adults 50 and over infected with the Human Immunodeficiency Virus (HIV), including those who have progressed to Acquired Immune Deficiency Syndrome (AIDS.)^1,2,3

In just over a decade, the number of HIV-positive individuals 50 and over in New Jersey increased seven-fold, from 1,047 cases in 1992 to 7,440 cases in 2003. One third (31.4%) of this group represent new cases, those whom the prevention message did not reach and who contracted the virus after reaching the age of 50. The other two-thirds (68.6%) became infected at a younger age and have now joined a growing population aging with the virus in the era of highly active anti-retroviral therapy (HAART).¹ By June 2006, the New Jersey Department of Health and Senior Services, Division of HIV/AIDS Services (NJDHSS-DHAS) reported that the percentage of the HIV/AIDS-infected population who were 50 or older had risen to 30% of all cases of HIV/AIDS in New Jersey, a total of 10,082 people age 50 or older.³

This article is designed to enhance the role of New Jersey’s clinicians in reducing the transmission of HIV among people 50 and older, identifying those who are HIV-positive but not yet in treatment, and enhancing care of the growing population of patients coping simultaneously with HIV infection and aging.

CLINICAL INSIGHTS

Age, Immunity & HIV Infection

A number of studies have found that AIDS survival is inversely proportional to age at the time of AIDS diagnosis.Factors associated with advanced age, such as the natural decline of the immune function, and delayed diagnosis, contribute to shortened survival.⁴

Older patients with chronic HIV infection have a more pronounced depletion of CD4 cells than younger ones. In a recent European study, immune recovery for 1,956 patients was found to be inversely related to age, with older patients experiencing poorer recovery and a shorter life span.⁵ Although an age of over 55 was associated with decreased AIDS-free survival, it was not associated with decreased time from diagnosis of AIDS to death.⁶

The progression from HIV to AIDS to death is affected not only by age at time of diagnosis but also by co-morbidities commonly associated with aging such as cardiovascular disease, cerebrovascular disease, diabetes mellitus, and chronic lung disease, all of which are statistically significant predictors of shortened survival, independent of age over 55 years.^7,8

Further study found that patients over 50 years were more likely to meet criteria for AIDS at the time of diagnosis of HIV infection than younger patients^.7 Due to delayed diagnosis, older patients are more likely to die within the same month as their AIDS diagnosis.⁷ In contrast, another study did not observe any difference between older and younger individuals in viral suppression, immune recovery, or clinical outcome, despite the greater presence of comorbid conditions in the older age group.⁹

Opportunistic Infections & Other Conditions

Elderly patients with AIDS present with similar opportunistic infections (OI) as younger patients, but they may be misdiagnosed as having other diseases that occur in their age group, such as Alzheimer’s disease,¹⁰ bacterial or viral pneumonia,¹¹ malnutrition, and occult malignancy.¹² Among AIDS patients older than 50 years, as with younger patients, the most common opportunistic infections are pneumocystis jiroveci pneumonia (PCP), wasting syndrome, candida esophagitis, and Kaposi’s Sarcoma. These conditions are are treated similarly regardless of age.¹³ Confronted with the same opportunistic infections as younger AIDS patients, older patients have poorer outcomes, including higher morbidity due to PCP, higher rates of disseminated tuberculosis and more severe herpes zoster.¹⁴ Additional challenges for clinicians are reflected in several reports describing atypical presentation of diseases leading to delayed diagnoses. The introduction of highly active antiretroviral drugs (HAART), and the related recovery of immune systems in treated patients of all ages, have led to a dramatic drop in the frequency of most AIDSrelated OI’s, especially those related to very low CD4 count. This has produced a modified clinical picture with significantly reduced morbidity and mortality.¹⁵