Shannon M. Lynch

Dr. Shannon M. Lynch

orcid

Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 January 2016 in PLOS ONE
Verified
Journal Article
Open access
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SLShannon M. Lynch
Shannon M. Lynch
MPM. K. Peek
M. K. Peek
NMNandita Mitra
Nandita Mitra
KRKrithika Ravichandran
Krithika Ravichandran
CBCharles Branas
Charles Branas
HRHarold Riethman
Harold Riethman
Leukocyte telomere length(LTL) has been associated with age, self-reported race/ethnicity, gender, education, and psychosocial factors, including perceived stress, and depression. However, inconsistencies in associations of LTL with disease and other phenotypes exist across studies. Population characteristics, including race/ethnicity, laboratory methods, and statistical approaches in LTL have not been comprehensively studied and could explain inconsistent LTL associations. LTL was measured using Southern Blot in 1510 participants from a multi-ethnic, multi-center study combining data from 3 centers with different population characteristics and laboratory processing methods. Main associations between LTL and psychosocial factors and LTL and race/ethnicity were evaluated and then compared across generalized estimating equations(GEE) and linear regression models. Statistical models were adjusted for factors typically associated with LTL(age, gender, cancer status) and also accounted for factors related to center differences, including laboratory methods(i.e., DNA extraction). Associations between LTL and psychosocial factors were also evaluated within race/ethnicity subgroups (Non-hispanic Whites, African Americans, and Hispanics). Beyond adjustment for age, gender, and cancer status, additional adjustments for DNA extraction and clustering by center were needed given their effects on LTL measurements. In adjusted GEE models, longer LTL was associated with African American race (Beta(β)(standard error(SE)) = 0.09(0.04), p-value = 0.04) and Hispanic ethnicity (β(SE) = 0.06(0.01), p-value = 0.02) compared to Non-Hispanic Whites. Longer LTL was also associated with less than a high school education compared to having greater than a high school education (β(SE) = 0.06(0.02), p-value = 0.04). LTL was inversely related to perceived stress (β(SE) = -0.02(0.003), p<0.001). In subgroup analyses, there was a negative association with LTL in African Americans with a high school education versus those with greater than a high school education(β(SE) = -0.11(0.03), p-value<0.001). Laboratory methods and population characteristics that differ by center can influence telomere length associations in multicenter settings, but these effects could be addressed through statistical adjustments. Proper evaluation of potential sources of bias can allow for combined multicenter analyses and may resolve some inconsistencies in reporting of LTL associations. Further, biologic effects on LTL may differ under certain psychosocial and racial/ethnic circumstances and could impact future health disparity studies.

14 February 2022 in Cancer Medicine
Verified
Journal Article
Open access
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KSKristen A. Sorice
Kristen A. Sorice
CFCarolyn Y. Yun Fang
Carolyn Y. Yun Fang
DWDaniel Wiese
Daniel Wiese
AOAngel Ortiz
Angel Ortiz
YCYuku Chen
Yuku Chen
SLShannon M. Lynch
Shannon M. Lynch
Background: There is extensive interest in understanding how neighborhood socioeconomic status (nSES) may affect cancer incidence or survival. However, variability regarding items included and approaches used to form a composite nSES index presents challenges in summarizing overall associations with cancer. Given recent calls for standardized measures of neighborhood sociodemographic effects in cancer disparity research, the objective of this systematic review was to identify and compare existing nSES indices studied across the cancer continuum (incidence, screening, diagnosis, treatment, survival/mortality) and summarize associations by race/ethnicity and cancer site to inform future cancer disparity studies.Methods: Using PRISMA guidelines, peer‐reviewed articles published between 2010 and 2019 containing keywords related to nSES and cancer were identified in PubMed.Results: Twenty‐four nSES indices were identified from 75 studies. In general, findings indicated a significant association between nSES and cancer outcomes (n = 64/75 studies; 85.33%), with 42/64 (65.63%) adjusting for highly‐correlated individual SES factors (e.g., education). However, the direction of association differed by cancer site, race/ethnicity, and nSES index.Conclusions: This review highlights several methodologic and conceptual issues surrounding nSES measurement and potential associations with cancer disparities. Recommendations pertaining to the selection of nSES measures are provided, which may help inform disparity‐related disease processes and improve the identification of vulnerable populations in need of intervention.

KMKiara Mayhand
Kiara Mayhand
EHElizabeth A. Handorf
Elizabeth A. Handorf
AOAngel G. Ortiz
Angel G. Ortiz
EGEvelyn T. Gonzalez
Evelyn T. Gonzalez
ADAmie Devlin
Amie Devlin
SLShannon M. Lynch
Shannon M. Lynch
Despite the effectiveness of screenings in reducing colorectal cancer (CRC) mortality, ~25% of US adults do not adhere to screening guidelines. Prior studies associate socioeconomic status (SES) with low screening adherence and suggest that neighborhood deprivation can influence CRC outcomes. We comprehensively investigated the effect of neighborhood SES circumstances (nSES), individual SES, and race/ethnicity on adherence to CRC screening in a multiethnic cross-sectional study. Participant surveys assessing 32 individual-level socioeconomic and healthcare access measures were administered from 2017 to 2018. Participant data were joined with nine nSES measures from the US Census at the census tract level. Univariate, LASSO, and multivariable mixed-effect logistic regression models were used for variable reduction and evaluation of associations. The total study population included 526 participants aged 50–85; 29% of participants were non-adherent. In the final multivariable model, age (p = 0.02) and Non-Hispanic Black race (p = 0.02) were associated with higher odds of adherence. Factors associated with lower adherence were home rental (vs. ownership) (p = 0.003), perception of low healthcare quality (p = 0.006), no routine checkup within two years (p = 0.002), perceived discrimination (p = 0.02), and nSES deprivation (p = 0.02). After comprehensive variable methods were applied, socioeconomic indicators at the neighborhood and individual level were found to contribute to low CRC screening adherence.

27 March 2017 in PLOS ONE
Verified
Journal Article
Open access
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SLShannon M. Lynch
Shannon M. Lynch
NMNandita Mitra
Nandita Mitra
MRMichelle Ross
Michelle Ross
CNCraig Newcomb
Craig Newcomb
KDKarl Dailey
Karl Dailey
TRTimothy R Rebbeck
Timothy R Rebbeck
Cancer results from complex interactions of multiple variables at the biologic, individual, and social levels. Compared to other levels, social effects that occur geospatially in neighborhoods are not as well-studied, and empiric methods to assess these effects are limited. We propose a novel Neighborhood-Wide Association Study(NWAS), analogous to genome-wide association studies(GWAS), that utilizes high-dimensional computing approaches from biology to comprehensively and empirically identify neighborhood factors associated with disease. Pennsylvania Cancer Registry data were linked to U.S. Census data. In a successively more stringent multiphase approach, we evaluated the association between neighborhood (n = 14,663 census variables) and prostate cancer aggressiveness(PCA) with n = 6,416 aggressive (Stage≥3/Gleason grade≥7 cases) vs. n = 70,670 non-aggressive (Stage<3/Gleason grade<7) cases in White men. Analyses accounted for age, year of diagnosis, spatial correlation, and multiple-testing. We used generalized estimating equations in Phase 1 and Bayesian mixed effects models in Phase 2 to calculate odds ratios(OR) and confidence/credible intervals(CI). In Phase 3, principal components analysis grouped correlated variables. We identified 17 new neighborhood variables associated with PCA. These variables represented income, housing, employment, immigration, access to care, and social support. The top hits or most significant variables related to transportation (OR = 1.05;CI = 1.001–1.09) and poverty (OR = 1.07;CI = 1.01–1.12). This study introduces the application of high-dimensional, computational methods to large-scale, publically-available geospatial data. Although NWAS requires further testing, it is hypothesis-generating and addresses gaps in geospatial analysis related to empiric assessment. Further, NWAS could have broad implications for many diseases and future precision medicine studies focused on multilevel risk factors of disease.

2 January 2024 in BMC Public Health
Verified
Journal Article
Open access
PDF file
GKGillian Kasper
Gillian Kasper
MMMahsa Momen
Mahsa Momen
KSKristen A. Sorice
Kristen A. Sorice
KMKiara N. Mayhand
Kiara N. Mayhand
EHElizabeth A. Handorf
Elizabeth A. Handorf
SLShannon M. Lynch
Shannon M. Lynch
Background: Although mammography can significantly reduce breast cancer mortality, many women do not receive their annual breast cancer screening. Differences in screening adherence exist by race/ethnicity, socioeconomic status (SES), and insurance status. However, more detailed investigations into the impact of neighborhood disadvantage and access to resources on screening adherence are lacking. Methods: We comprehensively examined the effect of individual social, economic, and demographic factors (n = 34 variables), as well as neighborhood level SES (nSES) indicators (n = 10 variables) on breast cancer screening adherence across a multi-ethnic population (n = 472). In this cross-sectional study, participants were surveyed from 2017 to 2018. The data was analyzed using univariate regression and LASSO for variable reduction. Significant predictors were carried forward into final multivariable mixed-effect logistic regression models where odds ratios (OR), 95% confidence intervals and p-values were reported. Results: Nineteen percent of participants were non-adherent to breast screening guidelines. Race/ethnicity was not associated with adherence; however, increasing age (OR = 0.97, 95%CI = 0.95–0.99, p = 0.01), renting a home (OR = 0.53, 95%CI = 0.30–0.94, p = 0.04), food insecurity (OR 0.46, 95%CI = 0.22–0.94, p = 0.01), and overcrowding (OR = 0.58, 95% CI = 0.32–0.94, p = 0.01) were significantly associated with lower breast cancer screening adherence. Conclusion: Socioeconomic indicators at the individual and neighborhood levels impact low breast cancer screening adherence and may help to inform future screening interventions.

24 February 2017 in Obesity Science & Practice
Verified
Journal Article
Open access
PDF file
SLShannon M. Lynch
Shannon M. Lynch
CSCarrie T. Stricker
Carrie T. Stricker
JBJustin C. Brown
Justin C. Brown
JBJohn M. Berardi
John M. Berardi
DVDavid Vaughn
David Vaughn
DSDavid B. Sarwer
David B. Sarwer
Summary: Purpose: Half of adult cancer survivors under age 50 years are obese. Excess body weight is associated with cancer recurrence, and effective weight loss interventions for younger cancer survivors are needed. Commercially available, online weight loss programmes are readily accessible, but few have been studied in this population. This study employed a single‐arm, pre‐post intervention (baseline‐6 month/baseline‐12 month comparisons) to preliminarily explore feasibility, efficacy and safety of an online, commercially available weight loss programme in breast (n = 30) and testicular (n = 16) cancer survivors under age 50 years.Methods: The intervention included three daily components: exercise, nutritional/behavioural modification strategies and health lessons. Intention‐to‐treat and completers analyses were conducted. Feasibility was measured by participation (number of participants enrolled/number screened), retention (number of participants attending 6/12 month study visit/number of enrolled) and self‐reported adherence rates (average of mean percent adherence to each of the three intervention components). Efficacy was assessed by changes in initial weight (percent weight loss). Safety was assessed by adverse events.Results: The mean participation rate was 42%. The retention rate was 59% at 6 and 49% at 12 months. The adherence rate for all participants (completers/dropouts/lost‐to‐follow‐up) was 50.1% at 6 and 44% at 12 months. Completers reported adherence rates of 68% at 12 months. Study participants lost 5.3% body weight at 12 months; completers lost 9%. Only three unexpected adverse events (unrelated to the intervention) were reported.Conclusion: Clinically significant weight loss was observed, although retention rates were low. Findings generally support preliminary feasibility, efficacy and safety of this online weight loss programme, and future randomized control trials should be explored.