AIDS Among Persons Aged ≥50 Years—United States, 1991-1996 FREE

MMWR. 1998;47:21-27

2 tables, 2 figures omitted

EARLY IN the human immunodeficiency virus (HIV) epidemic, infection occurred disproportionately among older persons as a result of transmission through receipt of contaminated blood or blood products. Through 1989, receipt of contaminated blood or blood products accounted for only 1% of cases among persons aged 13-49 years; in comparison, this risk factor accounted for 6%, 28%, and 64% of cases among persons aged 50-59 years, 60-69 years, and ≥70 years, respectively.¹ Because of implementation of voluntary donor deferral and routine screening of blood donations in 1985, the number and proportion of acquired immunodeficiency syndrome (AIDS) cases associated with this risk factor decreased among persons aged ≥50 years.² However, among persons aged ≥50 years, the number and proportion with AIDS associated with other modes of exposure increased. This report describes the characteristics of persons aged ≥50 years with AIDS reported during 1996 and presents trends in the incidence of AIDS-opportunistic illnesses (AIDS-OIs) diagnosed during 1991-1996 by mode of HIV exposure for persons aged ≥50 years. The findings indicate that, even though the incidence of AIDS-OIs during 1996 was higher among persons aged 13-49 years (89%), the proportion of AIDS-OIs accounted for by those aged ≥50 years (11%) was substantial.*

For persons with AIDS reported in 1996, the analysis included only cases reported during January 1-December 31, 1996. Trends in AIDS incidence were based on cumulative AIDS cases among persons aged ≥13 years reported to CDC through June 1997 from the 50 states, the District of Columbia, and the U.S. territories and were analyzed by sex, age, race/ethnicity, mode of exposure, and year of AIDS diagnosis.³ Estimates were adjusted for delays in reporting and for the anticipated reclassification of cases initially reported without an HIV risk/exposure.³ To adjust for the 1993 expansion of the AIDS reporting criteria,† estimates of the incidence of AIDS-OIs were calculated from the sum of cases reported with an AIDS-OI and cases with estimated dates of diagnosis of an AIDS-OI that were reported based only on immunologic criteria.³ AIDS-OI incidence was estimated quarterly through December 1996 (the most recent annual period for which reliable estimates were available). To calculate annual AIDS incidence rates, mid-year U.S. population estimates were used based on decennial census data.⁴

In 1996, of 68,473 persons aged ≥13 years reported with AIDS, 7459 (11%) were aged ≥50 years; this proportion has remained stable since 1991. Of those aged ≥50 years, 48% were aged 50-54 years, 26% were aged 55-59 years, 14% were aged 60-64 years, and 12% were aged ≥65 years. Males accounted for 84% of cases, and blacks accounted for the highest proportion (43%) by race/ethnicity. Although men who have sex with men (MSM) accounted for the highest proportion of cases by exposure category (36%), compared with persons aged 13-49 years, a higher proportion of cases among persons aged ≥50 years were reported without risk information (26%). For both age groups, the highest proportions of cases were in the South (35% and 37%, respectively) and Northeast (32% and 30%, respectively).‡

In 1996, persons aged ≥50 years were more likely than those aged 13-49 years to be reported with an AIDS-OI (e.g., wasting syndrome [7% versus 4%]§ and HIV encephal-opathy [3% versus 1%]§) than to be reported with severe immunosuppression and without an AIDS-OI (53% versus 58%).§ In addition, persons aged ≥50 years were more likely to have died within 1 month of their AIDS diagnosis (13% versus 6%),§ suggesting late diagnosis of HIV infection.

From 1991 to 1996, the proportionate increase in incident cases of AIDS-OIs was greater among persons aged ≥50 years (22%; from 5260 cases to 6400 cases)∥ than among persons aged 13-49 years (9%; from 46,000 cases to 50,300 cases). From 1991 to 1996, among men aged ≥50 years, the number of incident cases of AIDS-OIs among MSM remained stable (2900 cases each for 1991 and 1996), while incident cases among men whose risk was heterosexual contact increased 94% (from 360 cases to 700 cases) and incident cases among men reporting injecting-drug use (IDU) increased 53% (from 850 cases to 1300 cases). Among male recipients of contaminated blood or blood products, incident cases of AIDS-OIs decreased 48% (from 250 cases to 130 cases). Among women aged ≥50 years, cases attributed to heterosexual contact and IDU increased 106% (from 340 cases to 700 cases) and 75% (from 160 cases to 280 cases), respectively, while cases among recipients of contaminated blood or blood products decreased 33% (from 120 cases to 80 cases).

In both 1991 and 1996, the rate of AIDS-OIs was higher for persons aged 13-49 years than for persons aged ≥50 years; rates among men in both age groups were higher than among women. The rate ratios of AIDS-OIs for 1996 and 1991 were similar for both age groups of men (1.1, 1.0) and the same for both age groups of women (1.6).

Local, state, and territorial health depts. Div of HIV/AIDS Prevention-Surveillance and Epidemiology, National Center for HIV, STD, and TB Prevention, CDC.

Even though the incidence of AIDS-OIs during 1996 was higher among persons aged 13-49 years, the proportion accounted for by persons aged ≥50 years (11%) was substantial. The findings in this report suggest that persons aged ≥50 years may not be promptly tested for HIV infection following the onset of HIV-related illnesses. Specifically, the finding that a higher proportion of persons aged ≥50 years were reported with an AIDS-OI and died within 1 month of AIDS diagnosis suggests that persons aged ≥50 years had AIDS diagnosed later during the course of HIV infection than persons aged 13-49 years. Although older HIV-infected patients have a shorter observed AIDS-free interval and shorter survival period than younger HIV-infected patients,⁵ one reason for later diagnosis among persons aged ≥50 years is that physicians may be less likely to consider HIV infection among this group. This may result in missed opportunities for timely use of OI prophylaxis or antiretroviral therapies to prevent progression of disease. For example, AIDS-OIs that occur commonly among persons aged ≥50 years (e.g., HIV encephalopathy and wasting syndrome) mimic other diseases associated with aging (e.g., Alzheimer disease, depression, and malignancies). In addition, in 1996, a survey of primary-care physicians reported they were less likely to discuss symptoms suggestive of HIV infection or to counsel older patients for HIV testing than their younger patients.⁶ To increase opportunities for HIV testing of U.S. persons aged ≥50 years, health-care providers should be encouraged to discuss risk factors, obtain sexual and drug histories for patients, and consider HIV infection in the differential diagnosis of clinical illnesses that may represent HIV infection in this age group.

Persons aged ≥50 years also may not be promptly tested for HIV infection because they may not perceive themselves to be at risk for HIV infection. AIDS surveillance data indicate that higher proportions of persons aged ≥50 years with cases of AIDS are reported without an identified risk. In 1994, the prevalence of reported condom use was lower among sexually active persons aged ≥50 years who engaged in high-risk behaviors, and a higher proportion of these persons had never been tested for HIV, compared with younger persons who engaged in the same behaviors.⁷ During June 1990-October 1994, a study in 12 state and local health department clinics indicated that older women with heterosexually acquired AIDS were less likely than younger women to have used a condom before their HIV diagnosis and were less likely to have been tested for HIV before being hospitalized with an AIDS-OI.⁸

Because of the frequently long incubation period from HIV infection to AIDS diagnosis, many persons who were diagnosed with AIDS at age ≥50 years were probably infected as younger adults; therefore, prevention efforts also must be directed at adults who engage in high-risk sexual and drug-use behaviors. In addition, because of the impact of recent advances in treatment on AIDS incidence, the AIDS surveillance data in this report may underestimate the current impact of the HIV epidemic both in persons in this age group and younger persons.⁹ Therefore, surveillance for HIV infection and AIDS is important for monitoring HIV transmission—particularly among persons aged ≥50 years—and for evaluating the effectiveness of prevention programs. CDC supports HIV surveillance in 31 states and is developing technical guidance to assist all states and territories in conducting HIV and AIDS case surveillance.

References: 9 available.

*Single copies of this report will be available until January 23, 1999, from the CDC National AIDS Clearinghouse, P.O. Box 6003, Rockville, MD 20849-6003; telephone (800) 458-5231 or (301) 519-0459.

†Conditions in HIV-infected persons that were added to the AIDS case definition in 1993 included laboratory measures of severe immunosuppression (i.e., CD4⁺ T-lymphocyte count <200 cells/µL or percentage of total lymphocytes <14) and three clinical conditions (pulmonary tuberculosis, recurrent pneumonia, and invasive cervical cancer).

‡Northeast=Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont; Midwest=Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin; South=Alabama, Arkansas, Delaware, District of Columbia, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia, and West Virginia; and West=Alaska, Arizona, California, Colorado, Hawaii, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming.

§p<0.05 (Chi-square).

∥Estimates are adjusted for delays in reporting AIDS cases, the 1993 expansion of the AIDS case definition, and anticipated redistribution of cases initially reported with no identified risk, but not for incomplete reporting of cases. Adult/adolescent and total estimates of <200, 200-499, 500-999, and ≥1000 are rounded to the nearest 10, 20, 50, and 100, respectively.

MMWR. 1998;47:49-50

ON DECEMBER 23, 1997, the Portland region of the American Red Cross (ARC) notified the Oregon Health Division about a cluster of adverse ocular reactions among six patients who had received out-patient red blood cell (RBC) transfusions at a hospital in Washington; all patients experienced severe bilateral conjunctival erythema within 24 hours of transfusion. Since the initial report, 106 similar reactions in 74 patients in 14 states (Alabama, California, Connecticut, Maine, Michigan, Minnesota, Montana, Oklahoma, Oregon, Pennsylvania, Texas, Utah, Washington, and Wisconsin) have been identified. This report summarizes the preliminary findings from three of these states about the ongoing investigation of these reactions.

From November 15, 1997, through January 7, 1998, a total of 49 adverse ocular reactions were reported in 38 patients in Michigan, Oregon, and Washington. An adverse ocular reaction was defined as bilateral eye redness occurring after November 1, 1997, and within 24 hours of receiving a RBC product. Median age of patients was 59 years (range: 28-84 years), and 22 (58%) were male; all had an underlying oncologic or hematologic diagnosis. Median time from transfusion initiation to symptom onset was 20 hours (range: 1-24 hours). Reactions were characterized by severe conjunctival erythema and/or conjunctival hemorrhage (100%), eye pain (62%), headache (25%), periorbital edema (23%), arthralgias (19%), nausea (15%), dyspnea (6%), and rash (6%). Median time from symptom onset to resolution was 5 days (range: 2-21 days); two patients remained symptomatic at the time of the interview. All patients had received transfusions of leukocyte-reduced RBCs within 24 hours of symptom onset; four also had received platelets. For 45 of 46 patients for whom information was available, the patient had received at least one unit of blood filtered with the LeukoNet Prestorage Leukoreduction Filtration System (HemaSure Inc., Marlborough, Massachusetts),* one of several prestorage leukocyte-reducing methods used by ARC. In three reactions, patients also received blood filtered with another leukocyte-reducing prestorage method.

Because all initial reports of reactions were linked to specific lots of LeukoNet-filtered blood products, on December 31, 1997, ARC issued a nationwide voluntary quarantine of seven lots. On January 7, 1998, ARC expanded this nationwide quarantine to all LeukoNet-filtered blood products produced since October 1, 1997. No additional adverse reactions have been reported among persons who received transfusions since January 8, 1998. CDC, in collaboration with state health departments, the Food and Drug Administration (FDA), and ARC, is conducting an investigation to determine the source and extent of these reactions.

St John Hospital, Longview, Washington; M Goldoft, MD, P Stehr-Green, DrPH, State Epidemiologist, Washington State Dept of Health. K Hedberg, MD, DW Fleming, MD, State Epidemiologist, Oregon Health Div. W Hall, MD, DR Johnson, MD, Acting State Epidemiologist, Michigan Dept of Community Health. Center for Biologics Evaluation and Research, Center for Devices and Radiological Health, Office of Regulatory Affairs, Food and Drug Administration. Div of Applied Public Health Training (proposed), Epidemiology Program Office; Hospital Infections Program, National Center for Infectious Diseases; and EIS officers, CDC.

Short-term adverse transfusion events may be febrile, nonhemolytic transfusion reactions or hemolytic (i.e., RBC destruction by either immune or nonimmune mechanisms). Allergic transfusion reactions also can occur and range in clinical severity from minor urticarial reactions to anaphylaxis; such events usually occur during or soon after transfusion.¹

The most frequent use of leukocyte-reduced blood is to minimize the likelihood of febrile, nonhemolytic transfusion reactions, particularly in persons with underlying hematologic malignancies.¹ Leukocyte reduction also has been used to reduce alloimmunization and transfusion-transmitted infections.²

Leukocytes can be reduced from blood (1) immediately after collection by using a filter that is integral to the collection system (in-line filtration); (2) after collection through use of a filter that must be attached to the collection bag; and (3) immediately at or before transfusion. The first two methods are referred to as "pre-storage" filtration, and maximize leukocyte adherence and minimize cytokine release.

The underlying mechanism for the cluster of adverse reactions described in this report has not been determined. However, potential causes include a toxic reaction to a chemical or material used in the production of the blood-collection system, or an allergic response to an unidentified allergen in the collection-filtration system.^3- 4 To assist the ongoing investigation and to determine the source, mechanisms, and potential magnitude of these reactions, clinicians and blood bank personnel should report cases of post-transfusion adverse ocular reactions through state health departments to CDC's Hospital Infections Program, National Center for Infectious Diseases, telephone (404) 639-6413 and to FDA's MedWatch Program, telephone (800) 332-1088.

*Use of trade names and commercial sources is for identification only and does not imply endorsement by CDC or the U.S. Department of Health and Human Services.

MMWR. 1998;47:38

VACCINE SAFETY and Risk Communication, a live satellite broadcast, will be held February 26, 1998, from 8 AM to 10 AM eastern standard time (EST) with a repeat broadcast from noon to 2 PM EST. Cosponsors are CDC's National Immunization Program and the Public Health Training Network. This broadcast is designed for physicians, physician assistants, nurses, nurse practitioners, pharmacists, medical students, and others who provide vaccinations, counsel patients about vaccination, or establish immunization policy.

The course will enable health professionals to respond to parents' and patients' questions about vaccines. Toll-free telephone lines will be available for participants to interact with the instructors.

Additional information about the course and registration is available from state health department immunization programs. Continuing education credits will be offered based on 2.0 hours of instruction. Pharmacy and American Academy of Family Physicians' credits will not be offered for this course.

MMWR. 1998;47:39

OVERVIEW of Public Health Surveillance, a slide set created by CDC's Division of Public Health Surveillance and Informatics, Epidemiology Program Office, is now available on the World-Wide Web at http://www.cdc.gov/epo/dphsi/phs/overview.htm. The slide set presents general information on public health surveillance and was developed to promote better understanding of the uses and sources of public health surveillance data. Users can either download the entire slide set or select individual slides. In addition, a bibliography of related books and journal articles with information about public health surveillance is provided on the Internet site.

MMWR. 1998;47:39

THE TUBERCULOSIS Information Management System (TIMS) is a CDC-developed and CDC-distributed software. It is being used in the 59 U.S. reporting areas for national tuberculosis (TB) surveillance. Beginning January 1, 1998, this system replaced the CDC software, Software for Expanded Tuberculosis Surveillance (SURVS-TB) for TB surveillance reporting. TIMS usage is under way and will be distributed to 97% of the reporting areas. However, TIMS data reporting through the National Electronic Telecommunications System for Surveillance will not be available until February. Therefore, for the cumulative reports of provisional TB cases for 1998, some areas will display a "U" for unavailable in Table II, Provisional cases of selected notifiable diseases, United States. Additional information about TIMS is available from the TIMS Help Desk, Computers and Statistics Branch, Division of TB Elimination, National Center for HIV, STD, and TB Prevention, telephone (404) 639-8155.