Dana L. Haberling

American Indian and Alaska Native persons in the United States experience high rates of chlamydia and gonorrhea (CT/GC) infections, but the burden among persons receiving healthcare through the Indian Health Service (IHS) has not been recently described. Currently, there is no surveillance system to regularly monitor IHS-specific CT/GC burden and trends. We used two capture recapture (CRC) methods with two IHS medical records sources: diagnostic codes and laboratory test results linked by person within 30 days among persons ≥15 years during 2016 to 2021. Capture recapture estimates were used with the IHS population to create prevalence rates and compared to the medical records counts. CRC estimated 88 680 (1189 per 100 000) and 83 884 CT infections (1125) and 36 713 (492) and 35 930 GC infections (482). Diagnostic codes were 60% and 63% of CT and 54% and 56% of GC CRC estimates and combined with laboratory test results were 88% and 94% of CT and 86% and 88% of GC CRC estimates. These findings underscore the value of IHS medical records for estimating CT/GC infections and measuring undercounting of single source CT/GC medical records. These sources can be leveraged to provide surveillance estimates for monitoring trends; strategic outreach; and supporting testing, treatment, and staffing needs.

: Chromoblastomycosis, phaeohyphomycotic abscesses, and sporotrichosis are fungal diseases usually caused by traumatic inoculation that cause substantial morbidity and can lead to long-term sequalae and inability to work. Few studies have analyzed the epidemiological and clinical characteristics of these mycoses in the United States, particularly among minority populations. We estimated prevalence and described features of American Indian and Alaska Native (AI/AN) persons with these diseases using Indian Health Service (IHS) data during 2016–2022. Chromoblastomycosis and phaeohyphomycotic abscess prevalence was 9 per 1,000,000, and sporotrichosis prevalence was 5 per 1,000,000 IHS user population. Prevalence was highest in the Southern Plains region for both diseases. Several patients experienced amputation, tissue fibrosis or scarring, or lymphedema. These findings provide baseline data for monitoring prevalence or changes in geographic distribution of implantation mycoses in AI/AN persons. Although cases are rare, these findings underscore the need for standardized clinical guidance to prevent long-term disability and decreased quality of life.

Background: National case rates of chlamydia and gonorrhea (CT/GC) among American Indian and Alaska Native (AI/AN) persons are disproportionately high. The Indian Health Service (IHS), which provides health care to members of federally recognized tribes, does not currently have a dedicated CT/GC surveillance system. The purpose of this study was to validate the use of CT/GC diagnostic codes for estimating diagnosed CT/GC infections among AI/AN persons who use IHS services. Methods: We conducted a retrospective study using IHS medical records from all persons 15 years and older from 2016 to 2021. We linked records with CT (A56, A74) and GC (A54, O98.2) International Classification of Diseases, 10th Revision, Clinical Modification diagnostic codes to laboratory results within 30 days for each person. We calculated the sensitivity, specificity, and positive and negative predictive values of CT/GC diagnostic codes using laboratory test results as the reference standard. Results: We identified more than 1.6 million CT/GC laboratory tests, and 52,815 CT and 19,971 GC diagnostic codes. Diagnostic code sensitivity was slightly higher for CT (54%) than GC (50%). Specificity, positive predictive value, and negative predictive value were high for CT and GC (range, 83.3%–99.8%). About one-third of CT/GC diagnostic codes could not be linked to a test result. Conclusions: The validation indicates that diagnostic codes align well with linked laboratory test results. However, because of the relatively large number of diagnostic codes and positive test results that could not be linked, combining the 2 would inform more reliable estimates of diagnosed CT/GC infections among AI/AN persons who use IHS for health care.

Background: Kawasaki disease (KD) is a febrile illness of unknown etiology. Patients with Kawasaki disease shock syndrome (KDSS) may present with clinical signs of poor perfusion and systolic hypotension in addition to typical KD features. The United States Centers for Disease Control and Prevention analyzes and interprets large hospitalization databases as a mechanism for conducting national KD surveillance. Methods: The Kids’ Inpatient Database (KID), the National (Nationwide) Inpatient Sample (NIS), and the IBM MarketScan Commercial (MSC) and MarketScan Medicaid (MSM) databases were analyzed to determine KD-associated hospitalization rates and trends from 2006 to the most recent year of available data. KD and potential KDSS hospitalizations were defined using International Classification of Disease-Clinical Modification codes. Results: For the most recent year, the KD-associated hospitalization rates for children <5 years of age were 19.8 (95% CI: 17.2–22.3, KID: 2016), 19.6 (95% CI: 16.8–22.4, NIS: 2017), 19.3 (MSC: 2018), and 18.4 (MSM: 2018) per 100,000. There was no indication of an increase in KD rates over the time period. Rates of potential KDSS among children <18 years of age, ranging from 0.0 to 0.7 per 100,000, increased; coding indicated potential KDSS for approximately 2.8%–5.3% of KD hospitalizations. Conclusions: Analyses of these large, national databases produced consistent KD-associated hospitalization rates, with no increase over time detected; however, the percentage of KD hospitalizations with potential KDSS increased. Given reports of increasing incidence elsewhere and the recent identification of a novel virus-associated syndrome with possible Kawasaki-like features, continued national surveillance is important to detect changes in disease epidemiology.

Objectives: Hepatitis C virus (HCV) and HIV transmission in the United States may increase as a result of increasing rates of opioid use disorder (OUD) and associated injection drug use (IDU). Epidemiologic trends among American Indian/Alaska Native (AI/AN) persons are not well known. Methods: We analyzed 2010-2014 Indian Health Service data on health care encounters to assess regional and temporal trends in IDU indicators among adults aged ≥18 years. IDU indicators included acute or chronic HCV infection (only among adults aged 18-35 years), arm cellulitis and abscess, OUD, and opioid-related overdose. We calculated rates per 10 000 AI/AN adults for each IDU indicator overall and stratified by sex, age group, and region and evaluated rate ratios and trends by using Poisson regression analysis. Results: Rates of HCV infection among adults aged 18-35 increased 9.4% per year, and rates of OUD among all adults increased 13.3% per year from 2010 to 2014. The rate of HCV infection among young women was approximately 1.3 times that among young men. Rates of opioid-related overdose among adults aged <50 years were approximately 1.4 times the rates among adults aged ≥50 years. Among young adults with HCV infection, 25.6% had concurrent OUD. Among all adults with arm cellulitis and abscess, 5.6% had concurrent OUD. Conclusions: Rates of HCV infection and OUD increased significantly in the AI/AN population. Strengthened public health efforts could ensure that AI/AN communities can address increasing needs for culturally appropriate interventions, including comprehensive syringe services programs, medication-assisted treatment, and opioid-related overdose prevention and can meet the growing need for treatment of HCV infection.

American Indians and Alaska Natives (AI/ANs) may be uniquely vulnerable to coccidioidomycosis given the large population residing in the Southwestern United States. We describe coccidioidomycosis-associated hospitalizations and outpatient visits during 2001–2014 in the Indian Health Service (IHS) system and compare hospitalizations with data from the Agency for Healthcare Research and Quality’s National (Nationwide) Inpatient Sample (NIS). We identified hospitalizations in the IHS and the NIS and outpatient visits in the IHS using International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes 114.0–114.9. We calculated average annual hospitalization and outpatient visit rates per 1 000 000 population and used Poisson regression to calculate rate ratios (RRs) and 95% confidence intervals (CIs). We used multivariable logistic regression to assess factors associated with IHS hospitalization. AI/ANs had the highest average annual hospitalization rate (58.0; 95% CI, 49.5–66.6) of any racial/ethnic group in the NIS, compared with 13.4 (95% CI, 12.7–14.2) for non-Hispanic whites. IHS data showed a hospitalization rate of 37.0; the median length of stay (interquartile range) was 6 (3–10) days. The average annual outpatient visit rate in IHS was 764.2, and it increased from 529.9 in 2001 to 845.9 in 2014. Male sex, age ≥65 years, diabetes, and extrapulmonary or progressive coccidioidomycosis were independently associated with increased risk for hospitalization. Twenty-four percent of patients had ICD-9-CM codes for community-acquired pneumonia in the 3 months before coccidioidomycosis diagnosis. AI/ANs experience high coccidioidomycosis-associated hospitalization rates, high morbidity, and possible missed opportunities for earlier diagnosis. Yearly trends in IHS data were similar to the general increase in hospitalizations and reported cases nationwide in the same period.

Hepatitis C virus (HCV) disproportionately affects American Indians/Alaska Natives (AI/AN). The Indian Health Service (IHS), via federal and tribal health facilities provides medical services to an estimated 2.2 million AI/AN people in the United States. HCV diagnoses, defined by International Classification of Diseases 9th Revision, Clinical Modification (ICD-9-CM) codes, were analyzed from 2005 to 2015. Results showed 29,803 patients with an HCV diagnosis; 53.4% were among persons born 1945–1965 and overall HCV burden was higher among males than females. These data will help inform local, regional, and national efforts to address, plan for and carry out a national strategy to provide treatment for HCV infected patients and programs to prevent new HCV infections.

The objectives of this study were to use Indian Health Service (IHS) data from electronic health records to analyze human immunodeficiency virus (HIV) diagnoses among American Indian/Alaska Natives (AI/ANs) and to identify current rates and trends that can support data-driven policy implementation and resource allocation for this population. We analyzed provider visit data from IHS to capture all AI/AN patients who met a definition of a new HIV diagnosis from 2005 through 2014 by using International Classification of Diseases, Ninth Revision, Clinical Modification codes. We calculated rates and trends of new HIV diagnoses by age, sex, region, and year per 100 000 AI/ANs in the IHS user population. A total of 2273 AI/ANs met the definition of newly diagnosed with HIV from 2005 through 2014, an average annual rate of 15.1 per 100 000 AI/ANs. Most (356/391) IHS health facilities recorded at least 1 new HIV diagnosis. The rate of new HIV diagnoses among males (21.3 per 100 000 AI/ANs) was twice as high as that among females (9.5 per 100 000 AI/ANs; rate ratio = 2.2; 95% confidence interval, 2.1-2.4); by age, rates were highest among those aged 20-54 for males and females. By region, the Southwest region had the highest number (n = 1016) and rate (19.9 per 100 000 AI/ANs) of new HIV diagnoses. Overall annual rates of new HIV diagnoses were stable from 2010 through 2014, although diagnosis rates increased among males (P < .001) and those aged 15-19 (P < .001), 45-59 (P < .001), and 50-54 (P = .01). New HIV diagnoses, derived from provider visit data, among AI/ANs were stable from 2010 through 2014. AI/ANs aged 20-54, particularly men, may benefit from increased HIV prevention and screening efforts. Additional services may benefit patients in regions with higher rates of new diagnoses and in remote settings in which reported HIV numbers are low.