The estimated direct medical cost of sexually transmitted diseases among American youth, 2000

Perspectives on Sexual and Reproductive Health, Jan-Feb, 2004 by Harrell W. Chesson, John M. Blandford, Thomas L. Gift, Guoyu Tao, Kathleen L. Irwin

CONTEXT: Each year, millions of U.S. youth acquire sexually transmitted diseases (STDs). Estimates of the economic burden of STDs can help to quantify the impact of STDs on the nation's youth and on the payers of the cost of their medical care.

METHODS: We synthesized the existing literature on STD costs to estimate the lifetime medical cost per case of eight major STDs--HIV, human papillomavirus (HPV), genital herpes simplex virus type 2, hepatitis B, chlamydia, gonorrhea, trichomoniasis and syphilis. We then estimated the total burden of disease by multiplying these cost-per-case estimates by the approximate number of new cases of STDs acquired by youth aged 15-24.

RESULTS: The total estimated burden of the nine million new cases of these STDs that occurred among 15-24-yearolds in 2000 was $6.5 billion (in year 2000 dollars). Viral STDs accounted for 94 % of thee total burden ($6.2 billion), and non viral STDs accounted for 6% of the total burden ($0.4 billion). HIV and HPV were by far the most costly STDs in terms of total estimated direct medical costs, accounting for 90% of the total burden ($5.9 billion).

CONCLUSIONS: The large number of infections acquired by persons aged 15-24 and the high cost per case of viral STDs, particularly HIV, create a substantial economic burden.

Perspectives on Sexual and Reproductive Health, 2004, 36(1): 11-19

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Sexually transmitted diseases (STDs) have a considerable impact on the health of adolescents and young adults in the United States. In 2000, an estimated nine million cases of STDs occurred among persons aged 15-24. (1) In addition, STDs impose a substantial economic burden: The direct cost of STDs, including HIV, among all age-groups was estimated to be $9.3-15.5 billion in the United States in the mid-1990s, adjusted to year 2000 dollars. (2)

Assessing the economic burden of STDs is important for two main reasons. First, estimates of the cost of treating STDs among adolescents and young adults can help quantify the impact of STDs on the nation's youth and on those who pay for their medical care. In many cases, the payers are public programs; for example, one study of patients receiving care for HIV round that 47% were covered by Medicaid or Medicare, 33% had private insurance and 20% were uninsured. (3) Second, information on the medical expenses involved in treating STDs is needed for cost-effectiveness evaluations of prevention programs.

The costs associated with STDs can be divided into three main categories: direct, indirect and intangible. (4) Direct costs may be either medical or nonmedical. Direct medical costs of STDs generally refer to the expenses of treating acute STDs and the sequelae of untreated or inadequately treated acute STDs. Examples are the cost of clinician visits, hospitalization, diagnostic testing, drug treatments and therapeutic procedures. Other expenses associated with receiving medical treatment, such as the cost of transportation to and from medical services, are classified as direct nonmedical costs. Indirect costs of STDs generally refer to productivity losses (lost wages) attributable to STD-related illness. Intangible costs of STDs are related to the pain and suffering associated with STDs.

In this article, we present estimates of the direct medical costs of STDs, including HIV. We synthesize the existing literature to estimate the lifetime cost of STDs that were acquired in 2000 by Americans aged 15-24. To our knowledge, this is the first study of the economic burden of STDs among youth in the United States.

METHODS AND RESULTS

We focused on eight major STDs-HIV, human papillomavirus (HPV), genital herpes simplex virus type 2 (HSV-2), hepatitis B virus, chlamydia, gonorrhea, trichomoniasis and syphilis. Although we used common guidelines in estimating the cost of each of these STDs, our methods varied because of STD-specific differences in the probability and cost of long-term sequelae and in the availability of cost estimates.

All costs (including those obtained from previous studies) were adjusted for inflation to year 2000 dollars, using the medical care component of the Consumer Price Index for All Urban Consumers. (5) We examined the lifetime cost of new STD cases occurring among young Americans in 2000 (incidence costs) rather than the total cost in 2000 of existing cases of STDs and their sequelae among persons who were 15-24 years old at the rime of infection (prevalence costs).

Estimates of incidence costs, based on information available in the literature, include the more immediate expenses of treating acute infections as well as the future costs of sequelae, such as pelvic inflammatory disease (PID), that might develop if an infection is not treated or if treatment is delayed or inappropriate. Following conventional methods of cost analysis, we used discounting to convert future costs into present value equivalents. (6) Future costs were discounted by 3% annually. (7)

When cost-per-case estimates were not available in the literature or could not be derived readily from published data, we describe our methods in more detail. We calculated sex-specific estimates when sex-specific data on cost per case were available or could be derived from existing data and when sex-specific costs differed substantially. Costs of neonatal complications attributable to STDs were not included in this analysis, because available cost data were limited and the inclusion of neonatal complications would have added complexity to the analysis.