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Dive into the research topics where Tiffany G. Harris is active.

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Featured researches published by Tiffany G. Harris.


Journal of Epidemiology and Community Health | 2013

Neighbourhood food environments and body mass index among New York City adults

James H. Stark; Kathryn M. Neckerman; Gina S. Lovasi; Kevin Konty; James W. Quinn; Peter S. Arno; Deborah Viola; Tiffany G. Harris; Christopher C. Weiss; Michael D. M. Bader; Andrew Rundle

Background Studies evaluating the impact of the neighbourhood food environment on obesity have summarised the density or proximity of individual food outlets. Though informative, there is a need to consider the role of the entire food environment; however, few measures of whole system attributes have been developed. New variables measuring the food environment were derived and used to study the association with body mass index (BMI). Methods Individual data on BMI and sociodemographic characteristics were collected from 48 482 respondents of the 2002–2006 community health survey in New York City and linked to residential zip code-level characteristics. The food environment of each zip code was described in terms of the diversity of outlets (number of types of outlets present in a zip code), the density of outlets (outlets/km2) and the proportion of outlets classified as BMI-unhealthy (eg, fast food, bodegas). Results Results of the cross-sectional, multilevel analyses revealed an inverse association between BMI and food outlet density (−0.32 BMI units across the IQR, 95% CI −0.45 to −0.20), a positive association between BMI and the proportion of BMI-unhealthy food outlets (0.26 BMI units per IQR, 95% CI 0.09 to 0.43) and no association with outlet diversity. The association between BMI and the proportion of BMI-unhealthy food outlets was stronger in lower (<median for % poverty) poverty zip codes than in high-poverty zip codes. Conclusions These results support a more nuanced assessment of the impact of the food environment and its association with obesity.


Clinical Infectious Diseases | 2012

Active Case Finding and Prevention of Tuberculosis Among a Cohort of Contacts Exposed to Infectious Tuberculosis Cases in New York City

Holly Anger; Douglas Proops; Tiffany G. Harris; Jiehui Li; Barry N. Kreiswirth; Elena Shashkina; Shama D. Ahuja

BACKGROUND Tuberculosis contact investigation identifies individuals who may be recently infected with tuberculosis and are thus at increased risk for disease. Contacts with latent tuberculosis infection (LTBI) are offered chemoprophylaxis to prevent active disease; however, the effectiveness of this intervention is unclear as treatment completion is generally low. METHODS A retrospective cohort study of 30 561 contacts identified during investigation of 5182 cases of tuberculosis diagnosed in New York City, 1997-2003, was performed. We searched the NYC tuberculosis registry to identify contacts developing active tuberculosis within 4 years of follow-up. We estimated the following: number of contacts undergoing evaluation (ie, tuberculin skin test and/or chest radiograph) per prevalent case diagnosed; number of contacts with LTBI that need to be treated with standard chemoprophylaxis to prevent 1 active case. RESULTS Of 30 561 contacts, 27 293 (89%) were evaluated and 268 prevalent cases were diagnosed (102 contacts evaluated per prevalent case diagnosed, 95% confidence interval [CI], 90-115). LTBI was diagnosed in 7597 contacts, including 6001 (79%) who initiated chemoprophylaxis, 3642 (61%) who later completed treatment, and 2359 (39%) who did not complete treatment. During 4 years of follow-up, active tuberculosis was diagnosed in 46 contacts with LTBI, including 22 of 6001 (0.4%) who initiated chemoprophylaxis and 24 of 1596 (1.5%) who did not initiate treatment. The absolute risk reduction afforded by chemoprophylaxis initiation was 1.1% (95% CI, .6%-1.9%), leading to an estimated 88 contacts treated to prevent 1 tuberculosis case (95% CI, 53-164). CONCLUSIONS Contact investigation facilitates active case finding and tuberculosis prevention, even when completion rates of chemoprophylaxis are suboptimal.


American Journal of Obstetrics and Gynecology | 2009

Depot-medroxyprogesterone acetate and combined oral contraceptive use and cervical neoplasia among women with oncogenic human papillomavirus infection.

Tiffany G. Harris; Leslie Miller; Shalini L Kulasingam; Qinghua Feng; Nancy B. Kiviat; Stephen M. Schwartz; Laura A. Koutsky

OBJECTIVE The objective of the study was to examine the relationship of depot-medroxyprogesterone acetate (DMPA) and combined oral contraceptive (COC) use with cervical intraepithelial neoplasia (CIN). STUDY DESIGN Two case-control studies of women who presented for gynecologic care and underwent cytologic and human papillomavirus (HPV) testing were performed. The first included oncogenic HPV-positive women grouped based on histology: negative (n = 152), CIN1 (n = 133), and CIN2-3 or greater (n = 173). For the second, 2 groups were identified: negative HPV/negative histology (n = 107) and positive oncogenic HPV/negative histology (n = 152). RESULTS Among oncogenic HPV-positive women, DMPA use was inversely associated with CIN2-3 or greater (adjusted odds ratio [OR(adj)], 0.4; 95% confidence interval [CI], 0.2-1.1) and CIN1 (OR(adj), 0.1; 95% CI, 0.01-0.6); COC use was not associated with either. Among histologically negative women, DMPA use was associated with oncogenic HPV (OR(adj), 4.7; 95% CI, 1.4-15.8). CONCLUSION Among women with oncogenic HPV, hormonal contraceptive use was not associated with an increased risk of CIN2-3 or greater. Longer-term DMPA use may attenuate the colposcopic and histologic features of CIN because women reporting such use were more likely than others to have cervical oncogenic HPV without evidence of CIN.


Preventing Chronic Disease | 2014

Severe Obesity Among Children in New York City Public Elementary and Middle Schools, School Years 2006–07 Through 2010–11

Sophia E. Day; Kevin Konty; Maya Leventer-Roberts; Cathy Nonas; Tiffany G. Harris

Introduction Although studies have shown that childhood obesity overall is on the decline among New York City (NYC) public school children, the prevalence of severe childhood obesity has not been studied. Methods We used height and weight measurements of 947,765 NYC public school students aged 5 to 14 years in kindergarten through 8th grade (K–8), from school years 2006–07 through 2010–11. We used age- and sex-specific body mass index (BMI) percentiles according to Centers for Disease Control and Prevention growth charts to define childhood obesity (BMI ≥ 95th percentile) and severe childhood obesity (BMI ≥120% of 95th percentile) and to identify biologically implausible values (BIV). Multivariable logistic models tested for trends in obesity and severe obesity prevalence. To evaluate misclassification, we recalculated prevalence estimates for the most recent school year (2010–11) including the student records identified as BIV who were also declared severely obese (BMI ≥ 120% of 95th percentile). We refer to this subgroup of BIVs as “high BIV.” Results Severe obesity among NYC public school students in grades K–8 decreased 9.5% from the 2006–07 school year (6.3%) to the 2010–11 school year (5.7%), and obesity decreased 5.5% (from 21.9% to 20.7%). The prevalence of severe obesity and obesity was highest among minority, poor, and male children. Severe obesity declined in prevalence among every subgroup, with the greatest effect among white students and wealthy students. Severe obesity prevalence increased with age, and obesity prevalence peaked among those aged 7 to 10 years. For the 2010–11 school year, including high BIVs increased severe obesity prevalence from 5.7% to 6.6% and increased obesity prevalence from 20.7% to 21.5%. Conclusion Among all subgroups of NYC public school children in grades K–8, the reduction in severe obesity was greater than the reduction in overall obesity. Efforts to decrease obesity in NYC have affected the severely obese; however, monitoring of this specific subgroup should continue because of differences in trends and greater health risks.


Journal of Adolescent Health | 2014

The Effects of Changes in Physical Fitness on Academic Performance Among New York City Youth

Carla P. Bezold; Kevin Konty; Sophia E. Day; Magdalena Berger; Lindsey Harr; Michael Larkin; Melanie D. Napier; Cathy Nonas; Subir Saha; Tiffany G. Harris; James H. Stark

PURPOSE To evaluate whether a change in fitness is associated with academic outcomes in New York City (NYC) middle-school students using longitudinal data and to evaluate whether this relationship is modified by student household poverty. METHODS This was a longitudinal study of 83,111 New York City middle-school students enrolled between 2006-2007 and 2011-2012. Fitness was measured as a composite percentile based on three fitness tests and categorized based on change from the previous year. The effect of the fitness change level on academic outcomes, measured as a composite percentile based on state standardized mathematics and English Language Arts test scores, was estimated using a multilevel growth model. Models were stratified by sex, and additional models were tested stratified by student household poverty. RESULTS For both girls and boys, a substantial increase in fitness from the previous year resulted in a greater improvement in academic ranking than was seen in the reference group (girls: .36 greater percentile point improvement, 95% confidence interval: .09-.63; boys: .38 greater percentile point improvement, 95% confidence interval: .09-.66). A substantial decrease in fitness was associated with a decrease in academics in both boys and girls. Effects of fitness on academics were stronger in high-poverty boys and girls than in low-poverty boys and girls. CONCLUSIONS Academic rankings improved for boys and girls who increased their fitness level by >20 percentile points compared to other students. Opportunities for increased physical fitness may be important to support academic performance.


Journal of Medical Virology | 2009

Quantitative human papillomavirus 16 and 18 levels in incident infections and cervical lesion development.

Rachel L. Winer; Tiffany G. Harris; Long Fu Xi; Kathrin U. Jansen; James P. Hughes; Qinghua Feng; Carolee Welebob; Jesse Ho; Shu Kuang Lee; Joseph J. Carter; Denise A. Galloway; Nancy B. Kiviat; Laura A. Koutsky

Human papillomavirus (HPV) RNA levels may be a more sensitive early indicator of predisposition to carcinogenesis than DNA levels. We evaluated whether levels of HPV‐16 and HPV‐18 DNA and messenger RNA (mRNA) in newly detected infections are associated with cervical lesion development. Female university students were recruited from 1990 to 2004. Cervical samples for HPV DNA, HPV mRNA, and Papanicolaou testing were collected tri‐annually, and women were referred for colposcopically directed biopsy when indicated. Quantitative real‐time polymerase chain reaction of L1 and E7 DNA and E7 mRNA was performed on samples from women with HPV‐16 and HPV‐18 infections that were incidently detected by consensus PCR. Adjusting for other HPV types, increasing E7 cervical HPV‐16 mRNA levels at the time of incident HPV‐16 DNA detection were associated with an increased risk of cervical intraepithelial neoplasia grade 2–3 (HR per 1 log10 increase in mRNA = 6.36, 95% CI = 2.00–20.23). Increasing HPV‐16 mRNA levels were also associated with an increased risk of cervical squamous intraepithelial lesions; the risk was highest at the incident positive visit and decreased over time. Neither HPV‐16 E7 DNA levels nor HPV‐18 E7 DNA nor mRNA levels were significantly associated with cervical lesion development. Report of >1 new partner in the past 8 months (relative to no new partners) was associated with increased HPV mRNA (viral level ratio [VLR] = 10.05, 95% CI = 1.09–92.56) and increased HPV DNA (VLR = 16.80, 95% CI = 1.46–193.01). In newly detected HPV‐16 infections, increasing levels of E7 mRNA appear to be associated with an increased risk of developing cervical pre‐cancer. J. Med. Virol. 81:713–721, 2009


American Journal of Obstetrics and Gynecology | 2008

Evaluation of primary cervical cancer screening with an oncogenic human papillomavirus DNA test and cervical cytologic findings among women who attended family planning clinics in the United States.

Janet G. Baseman; Shalini L Kulasingam; Tiffany G. Harris; James P. Hughes; Nancy B. Kiviat; Constance Mao; Laura A. Koutsky

OBJECTIVE Our goal was to evaluate the performance of screening with (1) Papanicolaou and human papillomavirus (HPV) DNA testing and (2) Papanicolaou testing with reflex HPV testing of atypical squamous cells of undetermined significance for detecting cervical intraepithelial neoplasia grade 3 or more in clinics that serve low-income women in the United States. STUDY DESIGN There were 4799 women who were recruited primarily from Planned Parenthood clinics and who were screened with liquid-based Papanicolaou testing and HPV DNA testing and referred for biopsy based on a positive test result for oncogenic HPV DNA or a Papanicolaou test that showed atypical squamous cells of undetermined significance or more. RESULTS Among 931 women who were 30-50 years of age, the sensitivity of reflex HPV testing was 53.8% (range, 38.2%-72.3%). The sensitivity of HPV DNA and Papanicolaou testing was 91% (range, 74.6%-100%). The specificity of reflex HPV testing was 95.1% (range, 93.8%-96.3%). Generally, the specificity of HPV DNA and Papanicolaou testing was low. CONCLUSION Among US women who are >or=30 years old, HPV DNA and Papanicolaou testing is a reasonable cervical cancer screening strategy.


American Journal of Public Health | 2015

Neighborhood Contributions to Racial and Ethnic Disparities in Obesity Among New York City Adults

Sungwoo Lim; Tiffany G. Harris

Objectives. We assessed neighborhood confounding on racial/ethnic obesity disparities among adults in New York City after accounting for complex sampling, and how much neighborhood factors (walkability, percentage Black or Hispanic, poverty) contributed to this effect. Methods. We combined New York City Community Health Survey 2002-2004 data with Census 2000 zip code-level data. We estimated odds ratios (ORs) for obesity with 2 sets of regression analyses. First, we used the method incorporating the conditional pseudolikelihood into complex sample adjustment. Second, we compared ORs for race/ethnicity from a conventional multilevel model for each neighborhood factor with those from a hybrid fixed-effect model. Results. The weighted estimate for obesity for Blacks versus Whites (OR = 1.8; 95% confidence interval = 1.6, 2.0) was attenuated when we controlled neighborhood confounding (OR = 1.4; 95% confidence interval = 1.2, 1.6; first analysis). Percentage of Blacks in the neighborhood made a large contribution whereas the walkability contribution was minimal (second analysis). Conclusions. Percentage of Blacks in New York City neighborhoods explained a large portion of the disparity in obesity between Blacks and Whites. The study highlights the importance of estimating valid neighborhood effects for public health surveillance and intervention.


PLOS ONE | 2015

Influence of Jail Incarceration and Homelessness Patterns on Engagement in HIV Care and HIV Viral Suppression among New York City Adults Living with HIV/AIDS

Sungwoo Lim; Denis Nash; Laura M. Hollod; Tiffany G. Harris; Mary Clare Lennon; Lorna E. Thorpe

Objectives Both homelessness and incarceration are associated with housing instability, which in turn can disrupt continuity of HIV medical care. Yet, their impacts have not been systematically assessed among people living with HIV/AIDS (PLWHA). Methods We studied a retrospective cohort of 1,698 New York City PLWHA with both jail incarceration and homelessness during 2001–05 to evaluate whether frequent transitions between jail incarceration and homelessness were associated with a lower likelihood of continuity of HIV care during a subsequent one-year follow-up period. Using matched jail, single-adult homeless shelter, and HIV registry data, we performed sequence analysis to identify trajectories of these events and assessed their influence on engagement in HIV care and HIV viral suppression via marginal structural modeling. Results Sequence analysis identified four trajectories; 72% of the cohort had sporadic experiences of both brief incarceration and homelessness, whereas others experienced more consistent incarceration or homelessness during early or late months. Trajectories were not associated with differential engagement in HIV care during follow-up. However, compared with PLWHA experiencing early bouts of homelessness and later minimal incarceration/homelessness events, we observed a lower prevalence of viral suppression among PLWHA with two other trajectories: those with sporadic, brief occurrences of incarceration/homelessness (0.67, 95% CI = 0.50,0.90) and those with extensive incarceration experiences (0.62, 95% CI = 0.43,0.88). Conclusions Housing instability due to frequent jail incarceration and homelessness or extensive incarceration may exert negative influences on viral suppression. Policies and services that support housing stability should be strengthened among incarcerated and sheltered PLWHA to reduce risk of adverse health conditions.


American Journal of Epidemiology | 2015

All-Cause, Drug-Related, and HIV-Related Mortality Risk by Trajectories of Jail Incarceration and Homelessness Among Adults in New York City

Sungwoo Lim; Tiffany G. Harris; Denis Nash; Mary Clare Lennon; Lorna E. Thorpe

We studied a cohort of 15,620 adults who had experienced at least 1 jail incarceration and 1 homeless shelter stay in 2001-2003 in New York City to identify trajectories of these events and tested whether a particular trajectory was associated with all-cause, drug-related, or human immunodeficiency virus (HIV)-related mortality risk in 2004-2005. Using matched data on jail time, homeless shelter stays, and vital statistics, we performed sequence analysis and assessed mortality risk using standardized mortality ratios (SMRs) and marginal structural modeling. We identified 6 trajectories. Sixty percent of the cohort members had a temporary pattern, which was characterized by sporadic experiences of brief incarceration and homelessness, whereas the rest had the other 5 patterns, which reflected experiences of increasing, decreasing, or persistent jail or shelter stays. Mortality risk among individuals with a temporary pattern was significantly higher than those of adults who had not been incarcerated or stayed in a homeless shelter during the study period (all-cause SMR: 1.35, 95% confidence interval (CI): 1.14, 1.59; drug-related SMR: 4.60, 95% CI: 3.17, 6.46; HIV-related SMR: 1.54, 95% CI: 1.03, 2.21); all-cause and HIV-related SMRs in other patterns were not statistically significantly different. When we compared all 6 trajectories, the temporary pattern was more strongly associated with higher mortality risk than was the continuously homelessness pattern. Institutional interventions to reduce recurrent cycles of incarceration and homelessness are needed to augment behavioral interventions to reduce mortality risk.

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Shama D. Ahuja

New York City Department of Health and Mental Hygiene

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Sungwoo Lim

New York City Department of Health and Mental Hygiene

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Kevin Konty

New York City Department of Health and Mental Hygiene

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Aldo Crossa

New York City Department of Health and Mental Hygiene

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Amber Levanon Seligson

New York City Department of Health and Mental Hygiene

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Douglas Proops

New York City Department of Health and Mental Hygiene

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Holly Anger

New York City Department of Health and Mental Hygiene

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