HIV Screening Can Be Cost-Effective at an Advanced Age
By Michael Smith
DURHAM, N.C., 17 june 2008-- As more and more older Americans remain sexually active, HIV screening should be considered for some until age 74, researchers here said.Screening in older adults can make economic sense if the HIV prevalence in the population to be tested is 0.1% or greater, according to Gillian Sanders, Ph.D., of Duke University's clinical research institute and colleagues. It's even more cost-effective if less-expensive "streamlined" screening is used and if the patient has a sexual partner at risk for HIV, Dr. Sanders and colleagues said in the June 17 issue of the Annals of Internal Medicine.
Current CDC guidelines call for routine screening of Americans ages 13 through 64, Dr. Sanders said, but a mathematical model -- based on available prevalence data and other factors -- suggests that cutoff may be too early.
"Even if a person is over 65, the risk factors (for HIV) should still be looked at," Dr. Sanders said. "Prevalence is higher than people think -- and it doesn't have to be that high for screening to make sense."
Although HIV is often thought of as a disease of young adults, she noted that "19% of those infected were diagnosed at 50 or older."
The computer model that Dr. Sanders and colleagues used tracked older patients over their lifetime, noting whether they were screened, their HIV status, the clinical course of HIV, the effects of HIV transmission, and the cost and effects of treatment.
In the model, they included patients ages 55 through 74. Estimates of sexual activity, HIV prevalence, the cost of screening and testing, and other factors were taken from published literature, the researchers said.
Under various assumptions, screening at any of the tested ages could be cost-effective, they found, in terms of the standard measure, quality-adjusted life-years (QALYs).
For instance, if the prevalence of unidentified HIV is 0.5%, and a patient has an uninfected partner at risk for infection, a conventional one-time screening program led to incremental cost-effectiveness of $30,020 per QALY for a 65-year-old patient.
For a similar patient of 75, the incremental cost-effectiveness was $41,520 per QALY, the researchers found.
If the prevalence of HIV is lower -- at 0.1% -- the incremental cost-effectiveness worsens, at $91,410 per QALY for the 65-year-old and more than $100,000 per QALY for patients 70 or older.
The cost-effectiveness is also worse if the patient does not have a sexual partner at risk for HIV, the researchers said.
On the other hand, streamlined screening -- in which pre-testing counseling is minimal and post-test counseling is extensive only in the case of a positive result -- improved the cost-effectiveness for all ages.
The model's results depend on how much HIV there is in a population and how sexually active patients are, Dr. Sanders and colleagues said -- data that are not easy to come by.
But in earlier research among 8,627 veterans they found the prevalence of undocumented HIV infection to be 0.7% in outpatients 55 through 64, 0.5% in those 65 through 74, and 0.1% in those 75 or older.
And a recent study of 3,005 U.S. adults found that 73% of people 57 through 64, 53% of those 65 through 74, and 26% of those 75 to 85 were sexually active.
On the basis of these data and the results of their analysis, the researchers recommended one-time voluntary HIV screening with streamlined counseling on a routine basis for everyone 55 through 64 years old.
They also urged one-time screening, targeted to sexually active people ages 65 through 74, if the HIV prevalence is greater than 0.1%.
Dr. Sanders said physicians should remain aware of the possibility of HIV infection, especially if any of the conventional risk factors are present, regardless of age.
"All of us also need to remember that age doesn't protect anyone from HIV," she said. "You're as vulnerable at 60 as you are at 16."
The study was supported by the Department of Veterans Affairs, the National Institute on Drug Abuse, the National Institute on Aging, the Ontario Ministry of Health and Long-Term Care, and the Ontario HIV Treatment Network. The authors reported no conflicts of interest.
Primary source: Annals of Internal MedicineSource reference:Sanders GD, et al "Cost-effectiveness of HIV screening in patients older than 55 years of age" Ann Intern Med 2008; 148: 889-903.
By Michael Smith
DURHAM, N.C., 17 june 2008-- As more and more older Americans remain sexually active, HIV screening should be considered for some until age 74, researchers here said.Screening in older adults can make economic sense if the HIV prevalence in the population to be tested is 0.1% or greater, according to Gillian Sanders, Ph.D., of Duke University's clinical research institute and colleagues. It's even more cost-effective if less-expensive "streamlined" screening is used and if the patient has a sexual partner at risk for HIV, Dr. Sanders and colleagues said in the June 17 issue of the Annals of Internal Medicine.
Current CDC guidelines call for routine screening of Americans ages 13 through 64, Dr. Sanders said, but a mathematical model -- based on available prevalence data and other factors -- suggests that cutoff may be too early.
"Even if a person is over 65, the risk factors (for HIV) should still be looked at," Dr. Sanders said. "Prevalence is higher than people think -- and it doesn't have to be that high for screening to make sense."
Although HIV is often thought of as a disease of young adults, she noted that "19% of those infected were diagnosed at 50 or older."
The computer model that Dr. Sanders and colleagues used tracked older patients over their lifetime, noting whether they were screened, their HIV status, the clinical course of HIV, the effects of HIV transmission, and the cost and effects of treatment.
In the model, they included patients ages 55 through 74. Estimates of sexual activity, HIV prevalence, the cost of screening and testing, and other factors were taken from published literature, the researchers said.
Under various assumptions, screening at any of the tested ages could be cost-effective, they found, in terms of the standard measure, quality-adjusted life-years (QALYs).
For instance, if the prevalence of unidentified HIV is 0.5%, and a patient has an uninfected partner at risk for infection, a conventional one-time screening program led to incremental cost-effectiveness of $30,020 per QALY for a 65-year-old patient.
For a similar patient of 75, the incremental cost-effectiveness was $41,520 per QALY, the researchers found.
If the prevalence of HIV is lower -- at 0.1% -- the incremental cost-effectiveness worsens, at $91,410 per QALY for the 65-year-old and more than $100,000 per QALY for patients 70 or older.
The cost-effectiveness is also worse if the patient does not have a sexual partner at risk for HIV, the researchers said.
On the other hand, streamlined screening -- in which pre-testing counseling is minimal and post-test counseling is extensive only in the case of a positive result -- improved the cost-effectiveness for all ages.
The model's results depend on how much HIV there is in a population and how sexually active patients are, Dr. Sanders and colleagues said -- data that are not easy to come by.
But in earlier research among 8,627 veterans they found the prevalence of undocumented HIV infection to be 0.7% in outpatients 55 through 64, 0.5% in those 65 through 74, and 0.1% in those 75 or older.
And a recent study of 3,005 U.S. adults found that 73% of people 57 through 64, 53% of those 65 through 74, and 26% of those 75 to 85 were sexually active.
On the basis of these data and the results of their analysis, the researchers recommended one-time voluntary HIV screening with streamlined counseling on a routine basis for everyone 55 through 64 years old.
They also urged one-time screening, targeted to sexually active people ages 65 through 74, if the HIV prevalence is greater than 0.1%.
Dr. Sanders said physicians should remain aware of the possibility of HIV infection, especially if any of the conventional risk factors are present, regardless of age.
"All of us also need to remember that age doesn't protect anyone from HIV," she said. "You're as vulnerable at 60 as you are at 16."
The study was supported by the Department of Veterans Affairs, the National Institute on Drug Abuse, the National Institute on Aging, the Ontario Ministry of Health and Long-Term Care, and the Ontario HIV Treatment Network. The authors reported no conflicts of interest.
Primary source: Annals of Internal MedicineSource reference:Sanders GD, et al "Cost-effectiveness of HIV screening in patients older than 55 years of age" Ann Intern Med 2008; 148: 889-903.
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