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Dive into the research topics where Christina Ludema is active.

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Featured researches published by Christina Ludema.


PLOS ONE | 2012

HPV Genotypes in High Grade Cervical Lesions and Invasive Cervical Carcinoma as Detected by Two Commercial DNA Assays, North Carolina, 2001-2006

Susan Hariri; Martin Steinau; Allen C. Rinas; Julia W. Gargano; Christina Ludema; Elizabeth R. Unger; Alicia L. Carter; Kathy Grant; Melanie Bamberg; James E. McDermott; Lauri E. Markowitz; Noel T. Brewer; Jennifer S. Smith

Background HPV typing using formalin fixed paraffin embedded (FFPE) cervical tissue is used to evaluate HPV vaccine impact, but DNA yield and quality in FFPE specimens can negatively affect test results. This study aimed to evaluate 2 commercial assays for HPV detection and typing using FFPE cervical specimens. Methods Four large North Carolina pathology laboratories provided FFPE specimens from 299 women ages18 and older diagnosed with cervical disease from 2001 to 2006. For each woman, one diagnostic block was selected and unstained serial sections were prepared for DNA typing. Extracts from samples with residual lesion were used to detect and type HPV using parallel and serial testing algorithms with the Linear Array and LiPA HPV genotyping assays. Findings LA and LiPA concordance was 0.61 for detecting any high-risk (HR) and 0.20 for detecting any low-risk (LR) types, with significant differences in marginal proportions for HPV16, 51, 52, and any HR types. Discordant results were most often LiPA-positive, LA-negative. The parallel algorithm yielded the highest prevalence of any HPV type (95.7%). HR type prevalence was similar using parallel (93.1%) and serial (92.1%) approaches. HPV16, 33, and 52 prevalence was slightly lower using the serial algorithm, but the median number of HR types per woman (1) did not differ by algorithm. Using the serial algorithm, HPV DNA was detected in >85% of invasive and >95% of pre-invasive lesions. The most common type was HPV16, followed by 52, 18, 31, 33, and 35; HPV16/18 was detected in 56.5% of specimens. Multiple HPV types were more common in lower grade lesions. Conclusions We developed an efficient algorithm for testing and reporting results of two commercial assays for HPV detection and typing in FFPE specimens, and describe HPV type distribution in pre-invasive and invasive cervical lesions in a state-based sample prior to HPV vaccine introduction.


AIDS | 2011

Meta-analysis of randomized trials on the association of prophylactic acyclovir and HIV-1 viral load in individuals coinfected with herpes simplex virus-2

Christina Ludema; Stephen R. Cole; Charles Poole; Haitao Chu; Joseph J. Eron

Objective:To summarize the randomized evidence regarding the association between acyclovir use and HIV-1 replication as measured by plasma HIV-1 RNA viral load among individuals coinfected with herpes simplex virus (HSV)-2. Design:Meta-analysis of seven randomized trials conducted between 2000 and 2009. Inclusion criteria composed of acyclovir or valacyclovir use as prophylaxis among individuals coinfected with HIV-1 and HSV-2 who were ineligible for highly active antiretroviral therapy. HIV-1 viral load was the outcome. Methods:Random-effects summarization was used to combine treatment effect estimates. Stratified and meta-regression analyses were used to compare estimated treatment effects by characteristics of trials and participants. Results:The summary treatment effect estimate was −0.33 (95% confidence interval: −0.56, −0.10, 95% population effects interval: −0.74, 0.08) log10 copies, an approximate halving of plasma viral load. However, there was marked heterogeneity (P < 0.001). Older median age, valacyclovir, higher compliance, earlier publication, and shorter study length were associated with a larger decrease in viral load as compared with their counterparts. Conclusion:Current evidence suggests a range of favorable effects of acyclovir on plasma HIV-1 viral load among persons coinfected with HSV-2.


American Journal of Epidemiology | 2014

Association between unprotected ultraviolet radiation exposure and recurrence of ocular herpes simplex virus.

Christina Ludema; Stephen R. Cole; Charles Poole; Jennifer S. Smith; Victor J. Schoenbach; Kirk R. Wilhelmus

Studies have suggested that exposure to ultraviolet (UV) light may increase risk of herpes simplex virus (HSV) recurrence. Between 1993 and 1997, the Herpetic Eye Disease Study (HEDS) randomized 703 participants with ocular HSV to receipt of acyclovir or placebo for prevention of ocular HSV recurrence. Of these, 308 HEDS participants (48% female and 85% white; median age, 49 years) were included in a nested study of exposures thought to cause recurrence and were followed for up to 15 months. We matched weekly UV index values from the National Oceanic and Atmospheric Administration to each participants study center and used marginal structural Cox models to account for time-varying psychological stress and contact lens use and selection bias from dropout. There were 44 recurrences of ocular HSV, yielding an incidence of 4.3 events per 1,000 person-weeks. Weighted hazard ratios comparing persons with ≥8 hours of time outdoors to those with less exposure were 0.84 (95% confidence interval (CI): 0.27, 2.63) and 3.10 (95% CI: 1.14, 8.48) for weeks with a UV index of <4 and ≥4, respectively (ratio of hazard ratios = 3.68, 95% CI: 0.43, 31.4). Though results were imprecise, when the UV index was higher (i.e., ≥4), spending 8 or more hours per week outdoors was associated with increased risk of ocular HSV recurrence.


Journal of Acquired Immune Deficiency Syndromes | 2016

Impact of Health Insurance, ADAP, and Income on HIV Viral Suppression among US Women in the Women's Interagency HIV Study, 2006-2009

Christina Ludema; Stephen R. Cole; Joseph J. Eron; Andrew Edmonds; G. Mark Holmes; Kathryn Anastos; Jennifer Cocohoba; Mardge H. Cohen; Hannah L.F. Cooper; Elizabeth T. Golub; Seble Kassaye; Deborah Konkle-Parker; Lisa R. Metsch; Joel Milam; Tracey E. Wilson; Adaora A. Adimora

Background:Implementation of the Affordable Care Act motivates assessment of health insurance and supplementary programs, such as the AIDS Drug Assistance Program (ADAP) on health outcomes of HIV-infected people in the United States. We assessed the effects of health insurance, ADAP, and income on HIV viral load suppression. Methods:We used existing cohort data from the HIV-infected participants of the Womens Interagency HIV Study. Cox proportional hazards models were used to estimate the time from 2006 to unsuppressed HIV viral load (>200 copies/mL) among those with Medicaid, private, Medicare, or other public insurance, and no insurance, stratified by the use of ADAP. Results:In 2006, 65% of women had Medicaid, 18% had private insurance, 3% had Medicare or other public insurance, and 14% reported no health insurance. ADAP coverage was reported by 284 women (20%); 56% of uninsured participants reported ADAP coverage. After accounting for study site, age, race, lowest observed CD4, and previous health insurance, the hazard ratio (HR) for unsuppressed viral load among those privately insured without ADAP, compared with those on Medicaid without ADAP (referent group), was 0.61 (95% CI: 0.48 to 0.77). Among the uninsured, those with ADAP had a lower relative hazard of unsuppressed viral load compared with the referent group (HR, 95% CI: 0.49, 0.28 to 0.85) than those without ADAP (HR, 95% CI: 1.00, 0.63 to 1.57). Conclusions:Although women with private insurance are most likely to be virally suppressed, ADAP also contributes to viral load suppression. Continued support of this program may be especially critical for states that have not expanded Medicaid.


Sexually Transmitted Diseases | 2015

Characteristics of African American Women and Their Partners With Perceived Concurrent Partnerships in 4 Rural Counties in the Southeastern US

Christina Ludema; Irene A. Doherty; Becky L. White; Olga Villar-Loubet; Eleanor McLellan-Lemal; Christine M. OʼDaniels; Adaora A. Adimora

Background To the individual with concurrent partners, it is thought that having concurrent partnerships confers no greater risk of acquiring HIV than having multiple consecutive partnerships. However, an individual whose partner has concurrent partnerships (partners concurrency) is at increased risk for incident HIV infection. We sought to better understand relationships characterized by partners concurrency among African American women. Methods A total of 1013 African American women participated in a cross-sectional survey from 4 rural Southeastern counties. Results Older age at first sex was associated with lower prevalence of partners concurrency (prevalence ratio, 0.70; 95% confidence interval, 0.57–0.87), but the participants age was not associated with partners concurrency. After adjusting for covariates, ever having experienced intimate partner violence (IPV) and forced sex were most strongly associated with partners concurrency (prevalence ratios, 1.61 [95% confidence intervals, 1.23–2.11] and 1.65 [1.20–2.26], respectively). Women in mutually monogamous partnerships were the most likely to receive economic support from their partners; women whose partners had concurrent partnerships did not report more economic benefit than did those whose partners were monogamous. Conclusions Associations between history of IPV and forced sex with partners concurrency suggest that women with these experiences may particularly benefit from interventions to reduce partners concurrency in addition to support for reducing IPV and other sexual risks. To inform these interventions, further research to understand partnerships characterized by partners concurrency is warranted.


Archives of Sexual Behavior | 2018

Associations Between Neighborhood Characteristics, Social Cohesion, and Perceived Sex Partner Risk and Non-Monogamy Among HIV-Seropositive and HIV-Seronegative Women in the Southern U.S.

Danielle F. Haley; Gina M. Wingood; Michael R. Kramer; Regine Haardörfer; Adaora A. Adimora; Anna Rubtsova; Andrew Edmonds; Neela D. Goswami; Christina Ludema; De Marc A. Hickson; Catalina Ramirez; Zev Ross; Hector Bolivar; Hannah L.F. Cooper

Neighborhood social and physical factors shape sexual network characteristics in HIV-seronegative adults in the U.S. This multilevel analysis evaluated whether these relationships also exist in a predominantly HIV-seropositive cohort of women. This cross-sectional multilevel analysis included data from 734 women enrolled in the Women’s Interagency HIV Study’s sites in the U.S. South. Census tract-level contextual data captured socioeconomic disadvantage (e.g., tract poverty), number of alcohol outlets, and number of non-profits in the census tracts where women lived; participant-level data, including perceived neighborhood cohesion, were gathered via survey. We used hierarchical generalized linear models to evaluate relationships between tract characteristics and two outcomes: perceived main sex partner risk level (e.g., partner substance use) and perceived main sex partner non-monogamy. We tested whether these relationships varied by women’s HIV status. Greater tract-level socioeconomic disadvantage was associated with greater sex partner risk (OR 1.29, 95% CI 1.06–1.58) among HIV-seropositive women and less partner non-monogamy among HIV-seronegative women (OR 0.69, 95% CI 0.51–0.92). Perceived neighborhood trust and cohesion was associated with lower partner risk (OR 0.83, 95% CI 0.69–1.00) for HIV-seropositive and HIV-seronegative women. The tract-level number of alcohol outlets and non-profits were not associated with partner risk characteristics. Neighborhood characteristics are associated with perceived sex partner risk and non-monogamy among women in the South; these relationships vary by HIV status. Future studies should examine causal relationships and explore the pathways through which neighborhoods influence partner selection and risk characteristics.


Sexually Transmitted Infections | 2017

Relationships between neighbourhood characteristics and current STI status among HIV-infected and HIV-uninfected women living in the Southern USA: A cross-sectional multilevel analysis

Danielle F. Haley; Michael R. Kramer; Adaora A. Adimora; Regine Haardörfer; Gina M. Wingood; Christina Ludema; Anna Rubtsova; De Marc A. Hickson; Zev Ross; Elizabeth T. Golub; Hector Bolivar; Hannah L.F. Cooper

Objectives Neighbourhood characteristics (eg, high poverty rates) are associated with STIs among HIV-uninfected women in the USA. However, no multilevel analyses investigating the associations between neighbourhood exposures and STIs have explored these relationships among women living with HIV infection. The objectives of this study were to: (1) examine relationships between neighbourhood characteristics and current STI status and (2) investigate whether the magnitudes and directions of these relationships varied by HIV status in a predominantly HIV-infected cohort of women living in the Southern USA. Methods This cross-sectional multilevel analysis tests relationships between census tract characteristics and current STI status using data from 737 women enrolled at the Womens Interagency HIV Studys southern sites (530 HIV-infected and 207 HIV-uninfected women). Administrative data (eg, US Census) described the census tract-level social disorder (eg, violent crime rate) and social disadvantage (eg, alcohol outlet density) where women lived. Participant-level data were gathered via survey. Testing positive for a current STI was defined as a laboratory-confirmed diagnosis of chlamydia, gonorrhoea, trichomoniasis or syphilis. Hierarchical generalised linear models were used to determine relationships between tract-level characteristics and current STI status, and to test whether these relationships varied by HIV status. Results Eleven per cent of participants tested positive for at least one current STI. Greater tract-level social disorder (OR=1.34, 95% CI 0.99 to 1.87) and social disadvantage (OR=1.34, 95% CI 0.96 to 1.86) were associated with having a current STI. There was no evidence of additive or multiplicative interaction between tract-level characteristics and HIV status. Conclusions Findings suggest that neighbourhood characteristics may be associated with current STIs among women living in the South, and that relationships do not vary by HIV status. Future research should establish the temporality of these relationships and explore pathways through which neighbourhoods create vulnerability to STIs. Trial registration number NCT00000797; results.


Journal of Womens Health | 2017

Effects of Health Insurance Interruption on Loss of Hypertension Control in Women With and Women Without HIV

Andrew Edmonds; Christina Ludema; Joseph J. Eron; Stephen R. Cole; Adebola Adedimeji; Mardge H. Cohen; Hannah L.F. Cooper; Margaret A. Fischl; Mallory O. Johnson; Denise D. Krause; Daniel Merenstein; Joel Milam; Tracey E. Wilson; Adaora A. Adimora

BACKGROUND Among low-income women with and without HIV, it is a priority to reduce age-related comorbidities, including hypertension and its sequelae. Because consistent health insurance access has been identified as an important factor in controlling many chronic diseases, we estimated the effects of coverage interruption on loss of hypertension control in a cohort of women in the United States. METHODS We analyzed prospective, longitudinal data from the Womens Interagency HIV Study. HIV-infected and HIV-uninfected women were included between 2005 and 2014 when they reported health insurance at consecutive biannual visits and had controlled hypertension, and were followed for any insurance break and loss of hypertension control. We estimated hazard ratios (HRs) by Cox proportional hazards regression with inverse-probability-of-treatment-and censoring weights (marginal structural models), and plotted the cumulative incidence of hypertension control loss. RESULTS Among 890 HIV-infected women, the weighted HR for hypertension control loss comparing health insurance interruption to uninterrupted coverage was 1.37 (95% confidence interval [CI], 0.99-1.91). Inclusion of AIDS Drug Assistance Program (ADAP) participation with health insurance modestly increased the HR (1.47; 95% CI, 1.04-2.07). Analysis of 272 HIV-uninfected women yielded a similar HR (1.39; 95% CI, 0.88-2.21). Additionally, there were indications of uninterrupted coverage having a protective effect on hypertension when compared with the natural course in HIV-infected (HR, 0.82; 95% CI, 0.61-1.11) and HIV-uninfected (HR, 0.78; 95% CI, 0.52-1.19) women. CONCLUSIONS This study provides evidence that health insurance continuity promotes hypertension control in key populations. Interventions that ensure coverage stability and ADAP access should be a policy priority.


American Journal of Hypertension | 2017

Health insurance type and control of hypertension among US women living with and without HIV infection in the women's interagency HIV study

Christina Ludema; Stephen R. Cole; Joseph J. Eron; G. Mark Holmes; Kathryn Anastos; Jennifer Cocohoba; Marge H. Cohen; Hannah L.F. Cooper; Elizabeth T. Golub; Seble Kassaye; Deborah Konkle-Parker; Lisa R. Metsch; Joel Milam; Tracey E. Wilson; Adaora A. Adimora

BACKGROUND Health care access is an important determinant of health. We assessed the effect of health insurance status and type on blood pressure control among US women living with (WLWH) and without HIV. METHODS We used longitudinal cohort data from the Womens Interagency HIV Study (WIHS). WIHS participants were included at their first study visit since 2001 with incident uncontrolled blood pressure (BP) (i.e., BP ≥140/90 and at which BP at the prior visit was controlled (i.e., <135/85). We assessed time to regained BP control using inverse Kaplan-Meier curves and Cox proportional hazard models. Confounding and selection bias were accounted for using inverse probability-of-exposure-and-censoring weights. RESULTS Most of the 1,130 WLWH and 422 HIV-uninfected WIHS participants who had an elevated systolic or diastolic measurement were insured via Medicaid, were African-American, and had a yearly income ≤


Journal of Health Care for the Poor and Underserved | 2015

Religiosity, Spirituality, and HIV Risk Behaviors among African American Women from Four Rural Counties in the Southeastern U.S.

Christina Ludema; Irene Doherty; Becky L. White; Cathy A. Simpson; Olga Villar-Loubet; Eleanor McLellan-Lemal; Christine O’Daniels; Adaora A. Adimora

12,000. Among participants living with HIV, comparing the uninsured to those with Medicaid yielded an 18-month BP control risk difference of 0.16 (95% CI: 0.10, 0.23). This translates into a number-needed-to-treat (or insure) of 6; to reduce the caseload of WLWH with uncontrolled BP by one case, five individuals without insurance would need to be insured via Medicaid. Blood pressure control was similar among WLWH with private insurance and Medicaid. There were no differences observed by health insurance status on 18-month risk of BP control among the HIV-uninfected participants. CONCLUSIONS These results underscore the importance of health insurance for hypertension control-especially for people living with HIV.

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Adaora A. Adimora

University of North Carolina at Chapel Hill

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Stephen R. Cole

University of North Carolina at Chapel Hill

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Andrew Edmonds

University of North Carolina at Chapel Hill

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Joseph J. Eron

University of North Carolina at Chapel Hill

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