Sexually Transmitted Diseases among American Indians in Arizona: An Important Public Health Disparity:

Sexually transmitted diseases (STDs) remain a serious, but often disregarded, public health threat in the U.S., with significant physical and economic repercussions. Untreated STDs can result in chronic pelvic pain, infertility, ectopic pregnancies, fetal demise, premature deliveries, cardiac and neurologic deficits, and death.1,2 Additionally, many STDs are asymptomatic, leaving individuals unaware that they are infected.1–3 For this reason, these infections frequently remain undetected and are quickly passed to others, including fetuses. It has been estimated that the annual direct medical costs of STDs, including human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), in the U.S. can extend to more than several billion dollars.3,4 Even more troublesome is that certain populations carry a much larger burden of this “hidden epidemic” than others.1 Included among these are American Indian (AI) populations.5,6 The national rates among AIs/Alaska Natives for chlamydia, gonorrhea, and syphilis are two to six times the comparable rates for non-Hispanic white (NHW) people.6,7 In addition, several studies have raised a concern about racial misclassification of AIs in multiple disease-surveillance databases, including those for STDs and HIV.8,9 These studies suggest that rates in AI populations are frequently underestimated. An examination of the Oklahoma state STD surveillance system, for example, found that accounting for racial misclassification increased chlamydia rates by 32%, gonorrhea rates by 57%, and syphilis rates by 27%.8 A second study looking at HIV/AIDS reporting systems in five states and one urban health center from 1984 to 2002 found that the percentages of AIs being misclassified as non-AI ranged from nearly 4% to 55%.9 The southwestern region of the U.S. has the largest population of AIs by region and has experienced particularly high STD rates. For example, in 2004, 92% of all the primary and secondary syphilis cases among AIs in the U.S. occurred in three Indian Health Service (IHS) Areas located in the southwest region—Navajo, Phoenix, and Albuquerque.6 Arizona contains portions of two of these Areas—Phoenix and Navajo. In addition, the IHS Tucson Area is located in its entirety within the south-central portion of the state.6 In 2007 and 2008, this Area experienced a syphilis outbreak among a large AI tribe.10,11 Although African Americans had the highest rates of both chlamydia and gonorrhea in Arizona during 2007, AIs had the second-highest rate of chlamydia (649 per 100,000 population) and the second-highest rate of gonorrhea (95 per 100,000 population) when compared with all other racial/ethnic groups. These rates were 1.7 and 1.2 times the overall state rates for chlamydia and gonorrhea, respectively.10 Significant racial disparities among STD case rates have persisted in Arizona. These racial disparities occur among individuals with reported chlamydia, gonorrhea, and syphilis infections, and AI populations in Arizona are greatly affected.10 To more clearly evaluate and better address these particular racial disparities, we performed a comparison of STD rates, geographic distribution, and time to treatment to inform surveillance, prevention, and education efforts.