Waist circumference-years and cancer risk: a prospective study of the association and comparison of predictive performance with waist circumference and body mass index.

BACKGROUND: Associations of waist circumferences (WC) and body mass index (BMI) measured once or over time, with cancer incidence were studied. WC is associated with some cancers independent of BMI. Analyses of cumulative central adiposity and cancer are lacking. We investigated associations between waist circumference-years, incorporating exposure time to WC ≥ 102 cm in men or ≥88 cm in women, and cancer, and compared this with single WC or BMI. METHODS: Serial WC measurements taken over 9 years in the prospective Atherosclerosis Risk in Communities Study (ARIC) predicted yearly WC. Cox proportional hazards regression estimated hazard ratios (HRs) of cancer incidence for waist circumference-years, WC or BMI, measured in Visit 4. Harrell's C-statistic quantified metric predictive performances. RESULTS: 10,172 participants were followed up from Visit 4 for cancer over a median 13.7 for men and 15.8 years for women. For obesity-related cancers, HRs per standard deviation waist circumference-years were 1.14 (95%CI:1.04,1.25) and 1.19 (95%CI:1.12,1.27), respectively. Differences in metric predictive performances were marginal. DISCUSSION: This is the first study to identify positive associations between waist circumference-years and cancer. Waist circumference-years did not provide additional information on cancer risk beyond that of WC and BMI. BMI is routinely measured in clinic so it may be preferred over WC.

Subsequent risk of cancer among adults with peripheral artery disease in the community: The atherosclerosis risk in communities (ARIC) study.

BACKGROUND AND AIMS: Several studies reported an increased cancer risk related to lower-extremity peripheral artery disease (PAD) but had important caveats: not accounting for key confounders like smoking, follow-up <10 years, or no race-specific results. To assess the long-term independent association of PAD with cancer incidence in a bi-racial community-based cohort. METHODS: We categorized 13,106 ARIC participants without cancer at baseline (mean age 54.0 [SD 5.7] years, 45.7 % male, and 26.1 % Black) into symptomatic PAD (clinical history or intermittent claudication), asymptomatic PAD (ankle-brachial index [ABI] ≤0.9), and five ABI categories (0.1-interval between 0.9 and 1.3 and > 1.3). We used cancer registries and medical records to ascertain cancer cases and ran multivariable Cox models. RESULTS: During the median follow-up of 25.3 years, there were 4143 incident cancer cases. 25-year cumulative incidence was 37.2 % in symptomatic PAD, 32.3 % in asymptomatic PAD, and 28.0-31.0 % in the other categories. Symptomatic and asymptomatic PAD remained significantly associated with cancer incidence after adjusting for potential confounders, including smoking and diabetes (hazard ratio [HR] 1.42 [1.05-1.92] and 1.24 [1.05-1.46], respectively). When stratified by smoking status, we observed a robust association of PAD (symptomatic and asymptomatic combined) vs. no PAD with cancer risk in ever smokers (HR 1.42 [1.21-1.67]) but not in never smokers. The results were most evident for lung cancer (HR 2.16 (95 %CI 1.65-2.83) for PAD vs. no PAD within ever smokers). CONCLUSIONS: Symptomatic and asymptomatic PAD conferred cancer risk, particularly among ever smokers and for lung cancer. Patients with PAD should receive evidence-based cancer prevention and screening.

Development, characterization, and replication of proteomic aging clocks: Analysis of 2 population-based cohorts.

BACKGROUND: Biological age may be estimated by proteomic aging clocks (PACs). Previous published PACs were constructed either in smaller studies or mainly in white individuals, and they used proteomic measures from only one-time point. In this study, we created de novo PACs and compared their performance to published PACs at 2 different time points in the Atherosclerosis Risk in Communities (ARIC) study of white and black participants (around 75% white and 25% black). MEDTHODS AND FINDINGS: A total of 4,712 plasma proteins were measured using SomaScan in blood samples collected in 1990 to 1992 from 11,761 midlife participants (aged 46 to 70 years) and in 2011 to 2013 from 5,183 late-life participants (aged 66 to 90 years). The de novo ARIC PACs were constructed by training them against chronological age using elastic net regression in two-thirds of healthy participants in midlife and late life and validated in the remaining one-third of healthy participants at the corresponding time point. We also computed 3 published PACs. We estimated age acceleration for each PAC as residuals after regressing each PAC on chronological age. We also calculated the change in age acceleration from midlife to late life. We examined the associations of age acceleration and change in age acceleration with mortality through 2019 from all-cause, cardiovascular disease (CVD), cancer, and lower respiratory disease (LRD) using Cox proportional hazards regression in participants (irrespective of health) after excluding the training set. The model was adjusted for chronological age, smoking, body mass index (BMI), and other confounders. We externally validated the midlife PAC using the Multi-Ethnic Study of Atherosclerosis (MESA) Exam 1 data. The ARIC PACs had a slightly stronger correlation with chronological age than published PACs in healthy participants at each time point. Associations with mortality were similar for the ARIC PACs and published PACs. For late-life and midlife age acceleration for the ARIC PACs, respectively, hazard ratios (HRs) per 1 standard deviation were 1.65 and 1.38 (both p < 0.001) for all-cause mortality, 1.37 and 1.20 (both p < 0.001) for CVD mortality, 1.21 (p = 0.028) and 1.04 (p = 0.280) for cancer mortality, and 1.68 and 1.36 (both p < 0.001) for LRD mortality. For the change in age acceleration, HRs for all-cause, CVD, and LRD mortality were comparable to the HRs for late-life age acceleration. The association between the change in age acceleration and cancer mortality was not significant. The external validation of the midlife PAC in MESA showed significant associations with mortality, as observed for midlife participants in ARIC. The main limitation is that our PACs were constructed in midlife and late-life participants. It is unknown whether these PACs could be applied to young individuals. CONCLUSIONS: In this longitudinal study, we found that the ARIC PACs and published PACs were similarly associated with an increased risk of mortality. These findings suggested that PACs show promise as biomarkers of biological age. PACs may be serve as tools to predict mortality and evaluate the effect of anti-aging lifestyle and therapeutic interventions.

Association Between Obesity and Risk of Total and Obesity-Related Cancer in People With Incident Cardiovascular Disease.

BACKGROUND: Cardiovascular disease (CVD) and cancer frequently co-occur due to shared risk factors such as obesity, which is linked to CVD and 14 cancer types. This study explores whether CVD pathophysiologies, combined with obesity, increase cancer risk, impacting clinical management. METHODS AND RESULTS: Data from the ARIC (Atherosclerosis Risk in Communities) study, spanning 28 years, were analyzed. The cohort included 5127 participants with incident CVD (myocardial infarction, stroke, heart failure, coronary heart disease), of whom 1511 developed a first primary cancer. Follow-up began at CVD diagnosis after Visit 1. Obesity was assessed using body mass index, waist circumference, and waist-to-hip ratio. Incidence rate differences between obesity groups were adjusted for age, sex, and center, whereas the obesity-cancer association was estimated using Fine-Gray regression adjusted for shared risk factors including smoking. Cancer incidence in obese individuals with CVD (body mass index: rate differences=226.6/100 000 person-years) was higher than in those with normal weight. Although obesity was not linked to overall cancer after adjusting for shared risk factors, it was nominally associated with obesity-related cancers. Specifically, women with CVD and obesity had increased obesity-related cancer risk (body mass index: hazard ratio, 1.67 [95% CI, 1.17-2.31]). No significant associations were found in men, even after excluding prostate cancer. CONCLUSIONS: This study suggests that obesity is linked to higher obesity-related cancer risk in women with incident CVD, independent of shared risk factors. Further research is needed to eliminate residual confounding, understand sex differences, and explore how CVD pathophysiologies and obesity together influence cancer risk.

Validation of candidate protein biomarkers previously identified by genetic instruments for prostate cancer risk: A prospective cohort analysis of directly measured protein levels in the ARIC study.

BACKGROUND: Multiple novel protein biomarkers have been shown to be associated with prostate cancer risk using genetic instruments. This study aimed to externally validate the associations of 30 genetically predicted candidate proteins with prostate cancer risk using aptamer-based levels in US Black and White men in the Atherosclerosis Risk in Communities (ARIC) study. Plasma protein levels were previously measured by SomaScan® using the blood collected in 1990-1992. METHODS: Among 4864 eligible participants, we ascertained 667 first primary prostate cancer cases through 2015. Hazard ratios (HRs) of prostate cancer and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression for tertiles of each protein. We adjusted for age, race, and other risk factors. RESULTS: Of the 30 proteins and considering a nominal p trend < 0.05, two were positively associated with prostate cancer risk-RF1ML (tertile 3 vs. 1: HR = 1.23; 95% CI 1.02-1.48; p trend = 0.037) and TPST1 (1.28, 95% CI 1.06-1.55; p trend = 0.0087); two were inversely associated-ATF6A (HR = 0.80, 95% CI 0.65-0.98; p trend = 0.028) and SPINT2 (HR = 0.74, 95% CI 0.61-0.90; p trend = 0.0025). One protein, KDEL2, which was nonlinearly associated (test-for-linearity: p < 0.01) showed a statistically significant lower risk in the second tertile (HR = 0.79, 95% CI 0.65-0.95). Of these five, four proteins-ATF6A, KDEL2, RF1ML, and TPST1-were consistent in the direction of association with the discovery studies. CONCLUSION: This study validated some pre-diagnostic protein biomarkers of the risk of prostate cancer.

Proteomic Aging Clocks and the Risk of Mortality among Longer-Term Cancer Survivors in the Atherosclerosis Risk in Communities (ARIC) Study.

Background: We constructed a new proteomic aging clock (PAC) and computed the published Lehallier's PAC to estimate biological age. We tested PACs' associations with mortality in longer-term cancer survivors and cancer-free participants. Methods: ARIC measured 4,712 proteins using SomaScan in plasma samples collected at multiple visits, including Visit 5 (2011-13), from 806 cancer survivors and 3,699 cancer-free participants (aged 66-90). In the training set (N=2,466 randomly selected cancer-free participants), we developed the new PAC using elastic net regression and computed Lehallier's PAC. Age acceleration was calculated as residuals after regressing each PAC on chronological age after excluding the training set. We used multivariable-adjusted Cox proportional hazards regression to examine the associations of age acceleration with all-cause, cardiovascular disease (CVD), and cancer mortality. Results: Both PACs were correlated with chronological age [r=0.70-0.75]. Age acceleration for these two PACs was similarly associated with all-cause mortality in cancer survivors [hazard ratios (HRs) per 1 SD=1.40-1.42, p<0.01]. The associations with all-cause mortality were similar in cancer survivors and cancer-free participants for both PACs [p-interactions=0.20-0.62]. There were also associations with all-cause mortality in breast cancer survivors for both PACs [HRs=1.54-1.72, p<0.01] and colorectal cancer survivors for the new PAC [HR=1.96, p=0.03]. Additionally, the new PAC was associated with cancer mortality in all cancer survivors. Finally, HRs=1.42-1.61 [p<0.01] for CVD mortality in cancer-free participants for two PACs but the association was insignificant in cancer survivors perhaps due to a limited number of outcomes. Conclusion: PACs hold promise as potential biomarkers for premature mortality in cancer survivors.

Incidence of prostate cancer in Medicaid beneficiaries with and without HIV in 2001-2015 in 14 states.

Prostate cancer (PCa) incidence is reportedly lower in men with HIV compared to men without HIV for unknown reasons. We describe PCa incidence by HIV status in Medicaid beneficiaries, allowing for comparison of men with and without HIV who are similar with respect to socioeconomic characteristics and access to healthcare. Men (N = 15,167,636) aged 18-64 with ≥7 months of continuous enrollment during 2001-2015 in 14 US states were retained for analysis. Diagnoses of HIV and PCa were identified using non-drug claims. We estimated cause-specific (csHR) comparing incidence of PCa by HIV status, adjusted for age, race-ethnicity, state of residence, year of enrollment, and comorbid conditions, and stratified by age and race-ethnicity. Hazard of PCa was lower in men with HIV than men without HIV (csHR = 0.89; 95% CI: 0.80, 0.99), but varied by race-ethnicity, with similar observations among non-Hispanic Black (csHR = 0.79; 95% CI: 0.69, 0.91) and Hispanic (csHR = 0.85; 95% CI: 0.67, 1.09), but not non-Hispanic white men (csHR = 1.17; 95% CI: 0.91, 1.50). Findings were similar in models restricted to men aged 50-64 and 40-49, but not in men aged 18-39. Reported deficits in PCa incidence by HIV status may be restricted to specific groups defined by age and race ethnicity.

Retention in care and antiretroviral therapy adherence among Medicaid beneficiaries with HIV, 2001-2015.

Disparities in HIV care by socioeconomic status, place of residence, and race/ethnicity prevent progress toward epidemic control. No study has comprehensively characterized the HIV care cascade among people with HIV enrolled in Medicaid - an insurance source for low-income individuals in the US. We analyzed data from 246,127 people with HIV enrolled in Medicaid 2001-2015, aged 18-64, living in 14 US states. We estimated the monthly prevalence of four steps of the care cascade: retained in care/adherent to ART; retained/not adherent; not retained/adherent; not retained/not adherent. Beneficiaries were retained in care if they had an outpatient care encounter every six months. Adherence was based on medication possession ratio. We estimated prevalence using a non-parametric multi-state approach, accounting for death as a competing event and for Medicaid disenrollment using inverse probability of censoring weights. Across 2001-2015, the proportion of beneficiaries with HIV who were retained/ART adherent increased, overall and in all subgroups. By 2015, approximately half of beneficiaries were retained in care, and 42% of beneficiaries were ART adherent. We saw meaningful differences by race/ethnicity and region. Our work highlights an important disparity in the HIV care cascade by insurance status during this time period.

Incidence of prostate cancer in Medicaid beneficiaries with and without HIV in 2001-2015 in 14 states.

Background: Prostate cancer is projected to be the most common cancer among people living with HIV; however, incidence of prostate cancer has been reported to be lower in men with HIV compared to men without HIV with little evidence to explain this difference. We describe prostate cancer incidence by HIV status in Medicaid beneficiaries, allowing for comparison of men with and without HIV who are similar with respect to socioeconomic characteristics and access to healthcare. Methods: Medicaid beneficiaries (N=15,167,636) aged 18-64 with ≥7 months of continuous enrollment during 2001-2015 in 14 US states were retained for analysis. Diagnoses of HIV and prostate cancer were identified using inpatient and other non-drug claims. We estimated cause-specific (csHR) and sub-distribution hazard ratios comparing incidence of prostate cancer by HIV status, adjusted for age, race-ethnicity, state of residence, year of enrollment, and comorbid conditions. Models were additionally stratified by age and race-ethnicity. Results: There were 366 cases of prostate cancer observed over 299,976 person-years among beneficiaries with HIV and 17,224 cases over 22,298,914 person-years in beneficiaries without HIV. The hazard of prostate cancer was lower in men with HIV than men without HIV (csHR=0.89; 95% CI: 0.80, 0.99), but varied by race-ethnicity, with similar observations among non-Hispanic Black (csHR=0.79; 95% CI: 0.69, 0.91) and Hispanic (csHR=0.85; 95% CI: 0.67, 1.09), but not non-Hispanic white men (csHR=1.17; 95% CI: 0.91, 1.50). Results were similar in models restricted to ages 50-64 and 40-49, except for a higher hazard of prostate cancer in Hispanic men with HIV in their 40s, while the hazard of prostate cancer was higher in men with HIV across all models for men aged 18-39. Conclusion: Reported deficits in prostate cancer incidence by HIV status may be restricted to specific groups defined by age and race-ethnicity.

Longer prostate stromal cell telomere length is associated with increased risk of death from other cancers.

Background: Telomeres are located at chromosomal termini and function to maintain genomic integrity. Telomere dysfunction is a well-recognized contributor to aging and age-related diseases, such as prostate cancer. Since telomere length is highly heritable, we postulate that stromal cell telomere length in the tissue of a particular solid organ may generally reflect constitutive stromal cell telomere length in other solid organs throughout the body. Even with telomere loss occurring with each round of cell replication, in general, telomere length in prostate stromal cells in mid-life would still be correlated with the telomere length in stromal cells in other organs. Thus, we hypothesize that prostate stromal cell telomere length and/or telomere length variability is a potential indicator of the likelihood of developing future solid cancers, beyond prostate cancer, and especially lethal cancer. Methods: To explore this hypothesis, we conducted a cohort study analysis of 1,175 men who were surgically treated for prostate cancer and were followed for death, including from causes other than their prostate cancer. Results: In this cohort study with a median follow-up of 19 years, we observed that longer prostate stromal cell telomere length measured in tissue microarray spots containing prostate cancer was associated with an increased risk of death from other solid cancers. Variability in telomere length among these prostate stromal cells was possibly positively associated with risk of death from other solid cancers. Conclusion: Studying the link between stromal cell telomere length and cancer mortality may be important for guiding the development of cancer interception and prevention strategies.

Receipt of Prostate-Specific Antigen Test in Medicaid Beneficiaries With and Without HIV in 2001-2015 in 14 States.

Studies have reported lower incidence of prostate cancer in men living with HIV compared with men without HIV for reasons that remain unclear. Lower prostate cancer screening in men living with HIV could explain these findings. We describe receipt of prostate-specific antigen (PSA) test each calendar year by HIV status in Medicaid beneficiaries enrolled in 14 U.S. states, 2001-2015. A total of 15,299,991 Medicaid beneficiaries aged 18-64 with ≥7 months of continuous enrollment were included in analyses. HIV diagnosis and PSA tests were identified using non-drug claims. Incidence rate ratios comparing receipt of PSA test by HIV status adjusted for age, race/ethnicity, state of residence, calendar year, comorbid conditions, benign prostatic conditions, and receipt of testosterone-replacement therapy were estimated using Poisson regression. Models were also stratified by state, and estimates were pooled using random-effects meta-analysis to account for heterogeneity by state. Models were additionally stratified by age and race/ethnicity. There were 42,503 PSA tests over 314,273 person-years and 1,669,835 PSA tests over 22,023,530 person-years observed in beneficiaries with and without HIV, respectively. The incidence of PSA test was slightly lower in men living with HIV than men without HIV (incidence rate ratio [IRR] = 0.98; 95% confidence interval [CI]: 0.97, 0.99) when adjusting for state. In the pooled estimate, the rate was higher among men living with HIV (IRR = 1.11; 95% CI: 0.97, 1.27). Pooled estimates indicated approximately equal or higher rates of PSA test in men living with HIV compared with men without HIV across models stratified by age and race/ethnicity groups. Findings do not support the hypothesis that differences in prostate cancer screening explain differences in incidence by HIV status.

Retention in care and antiretroviral therapy adherence among Medicaid beneficiaries with HIV, 2001-2015.

Disparities in HIV care by socioeconomic status, place of residence, and race/ethnicity prevent progress toward epidemic control. No study has comprehensively characterized the HIV care cascade among people with HIV enrolled in Medicaid - an insurance source for low-income individuals in the US. We analyzed data from 246,127 people with HIV enrolled in Medicaid 2001-2015, aged 18-64, living in 14 US states. We estimated monthly prevalence of four steps of the care cascade: retained in care/adherent to ART; retained/not adherent; not retained/adherent; not retained/not adherent. Beneficiaries were retained in care if they had an outpatient care encounter every six months. Adherence was based on medication possession ratio. We estimated prevalence using a non-parametric multi-state approach, accounting for death as a competing event and for Medicaid disenrollment using inverse probability of censoring weights. Across 2001-2015, the proportion of beneficiaries with HIV who were retained/ART adherent increased, overall and in all subgroups. By 2015, approximately half of beneficiaries were retained in care, and 42% of beneficiaries were ART adherent. We saw meaningful differences by race/ethnicity and region. Our work highlights an important disparity in the HIV care cascade by insurance status during this time period.

Incidence of Colon Cancer Among Medicaid Beneficiaries With or Without Human Immunodeficiency Virus Under Comparable Colorectal Cancer Screening Patterns.

Background: People with human immunodeficiency virus (HIV; PWH) in the United States have a lower incidence of colon cancer than the general population. The lower incidence may be explained by differences in receipt of screening. Thus, we sought to estimate colon cancer incidence under scenarios in which Medicaid beneficiaries, with or without HIV, followed the same screening protocols. Methods: We used data from 1.5 million Medicaid beneficiaries who were enrolled in 14 US states in 2001-2015 and aged 50-64 years; 72 747 beneficiaries had HIV. We estimated risks of colon cancer and death by age, censoring beneficiaries when they deviated from 3 screening protocols, which were based on Medicaid's coverage policy for endoscopies during the time period, with endoscopy once every 2, 4, or 10 years. We used inverse probability weights to control for baseline and time-varying confounding and informative loss to follow-up. Analyses were performed overall, by sex, and by race/ethnicity. Results: PWH had a lower incidence of colon cancer than beneficiaries without HIV. Compared with beneficiaries without HIV, the risk difference at age 65 years was -1.6% lower (95% confidence interval, -2.3% to -.7%) among PWH with the 2-year protocol and -0.8% lower (-1.3% to -.3%) with the 10-year protocol. Results were consistent across subgroup and sensitivity analyses. Conclusions: Our findings suggest that the lower risk of colon cancer that has been observed among PWH aged 50-64 years compared with those without HIV is not due to differences in receipt of lower endoscopy. Keywords: colon cancer, colorectal cancer screening, endoscopy, Medicaid, human immunodeficiency virus.

Determinants of receipt of prostate cancer screening among men living with HIV enrolled in an urban HIV Clinic in the United States over the period of 2000-2020.

BACKGROUND: Prostate cancer is projected to account for the greatest proportion of cancer-related burden among men with HIV. However, incidence is reportedly lower than in men without HIV, potentially due to differences in screening. Factors influencing receipt of screening in men with HIV are unknown. We described receipt of prostate-specific antigen (PSA) testing and assessed factors for association with receipt of PSA test. METHODS: Demographics, measures of HIV and related care, and non-HIV care were assessed for association with receipt of first PSA test in men ≥40 years old each calendar year in 2000-2020 using univariable and multivariable Poisson regression. Models were additionally stratified by calendar period to identify changes in determinants of PSA test as prostate cancer screening guidelines changed. RESULTS: Men (n = 2,063) 72% Non-Hispanic Black, median age of 47 (IQR: 41, 53), contributed median of 4.7 years (IQR: 2.3, 10.0) of follow-up. Receipt of antiretroviral therapy (aIRR = 1.33; 95% CI: 1.14, 1.55), engagement in HIV care (aIRR = 2.09; 95% CI: 1.66, 2.62), history of testosterone-replacement therapy (aIRR = 1.34; 95% CI: 1.19, 1.50), urologist evaluation (aIRR = 1.66; 95% CI: 1.35, 2.05), and receipt of PSA test in preceding two years (no elevated PSA aIRR = 2.37; 95% CI: 2.16, 2.61; elevated PSA aIRR = 4.35; 95% CI: 3.24, 5.84) were associated with PSA testing in men aged 50 or older. Associations varied across calendar time. CONCLUSION: Findings suggest men with greater interaction with healthcare are more likely to receive PSA test. Measures of control of HIV did not appear to influence the decision to screen.

BMI and breast cancer risk around age at menopause.

BACKGROUND: A high body mass index (BMI, kg/m2) is associated with decreased risk of breast cancer before menopause, but increased risk after menopause. Exactly when this reversal occurs in relation to menopause is unclear. Locating that change point could provide insight into the role of adiposity in breast cancer etiology. METHODS: We examined the association between BMI and breast cancer risk in the Premenopausal Breast Cancer Collaborative Group, from age 45 up to breast cancer diagnosis, loss to follow-up, death, or age 55, whichever came first. Analyses included 609,880 women in 16 prospective studies, including 9956 who developed breast cancer before age 55. We fitted three BMI hazard ratio (HR) models over age-time: constant, linear, or nonlinear (via splines), applying piecewise exponential additive mixed models, with age as the primary time scale. We divided person-time into four strata: premenopause; postmenopause due to natural menopause; postmenopause because of interventional loss of ovarian function (bilateral oophorectomy (BO) or chemotherapy); postmenopause due to hysterectomy without BO. Sensitivity analyses included stratifying by BMI in young adulthood, or excluding women using menopausal hormone therapy. RESULTS: The constant BMI HR model provided the best fit for all four menopausal status groups. Under this model, the estimated association between a five-unit increment in BMI and breast cancer risk was HR=0.87 (95% CI: 0.85, 0.89) before menopause, HR=1.00 (95% CI: 0.96, 1.04) after natural menopause, HR=0.99 (95% CI: 0.93, 1.05) after interventional loss of ovarian function, and HR=0.88 (95% CI: 0.76, 1.02) after hysterectomy without BO. CONCLUSION: The BMI breast cancer HRs remained less than or near one during the 45-55 year age range indicating that the transition to a positive association between BMI and risk occurs after age 55.

International Pooled Analysis of Leisure-Time Physical Activity and Premenopausal Breast Cancer in Women From 19 Cohorts.

PURPOSE: There is strong evidence that leisure-time physical activity is protective against postmenopausal breast cancer risk but the association with premenopausal breast cancer is less clear. The purpose of this study was to examine the association of physical activity with the risk of developing premenopausal breast cancer. METHODS: We pooled individual-level data on self-reported leisure-time physical activity across 19 cohort studies comprising 547,601 premenopausal women, with 10,231 incident cases of breast cancer. Multivariable Cox regression was used to estimate hazard ratios (HRs) and 95% CIs for associations of leisure-time physical activity with breast cancer incidence. HRs for high versus low levels of activity were based on a comparison of risk at the 90th versus 10th percentiles of activity. We assessed the linearity of the relationship and examined subtype-specific associations and effect modification across strata of breast cancer risk factors, including adiposity. RESULTS: Over a median 11.5 years of follow-up (IQR, 8.0-16.1 years), high versus low levels of leisure-time physical activity were associated with a 6% (HR, 0.94 [95% CI, 0.89 to 0.99]) and a 10% (HR, 0.90 [95% CI, 0.85 to 0.95]) reduction in breast cancer risk, before and after adjustment for BMI, respectively. Tests of nonlinearity suggested an approximately linear relationship (Pnonlinearity = .94). The inverse association was particularly strong for human epidermal growth factor receptor 2-enriched breast cancer (HR, 0.57 [95% CI, 0.39 to 0.84]; Phet = .07). Associations did not vary significantly across strata of breast cancer risk factors, including subgroups of adiposity. CONCLUSION: This large, pooled analysis of cohort studies adds to evidence that engagement in higher levels of leisure-time physical activity may lead to reduced premenopausal breast cancer risk.

Performance of the pooled cohort equations in cancer survivors: the Atherosclerosis Risk in Communities study.

BACKGROUND: Cancer survivors may have elevated atherosclerotic cardiovascular disease (ASCVD) risk. Therefore, we tested how accurately the American College of Cardiology/American Heart Association 2013 pooled cohort equations (PCEs) predict 10-year ASCVD risk in cancer survivors. OBJECTIVES: To estimate the calibration and discrimination of the PCEs in cancer survivors compared to non-cancer participants in the Atherosclerosis Risk in Communities (ARIC) study. METHODS: We evaluated the PCEs' performance among 1244 cancer survivors and 3849 cancer-free participants who were free of ASCVD at the start of follow-up. Each cancer survivor was incidence-density matched with up to five controls by age, race, sex, and study center. Follow-up began at the first study visit at least 1 year after the diagnosis date of the cancer survivor and finished at the ASCVD event, death, or end of follow-up. Calibration and discrimination were assessed and compared between cancer survivors and cancer-free participants. RESULTS: Cancer survivors had higher PCE-predicted risk, at 26.1%, compared with 23.1% for cancer-free participants. There were 110 ASCVD events in cancer survivors and 332 ASCVD events in cancer-free participants. The PCEs overestimated ASCVD risk in cancer survivors and cancer-free participants by 45.6% and 47.4%, respectively, with poor discrimination in both groups (C-statistic for cancer survivors = 0.623; for cancer-free participants, C = 0.671). CONCLUSIONS: The PCEs overestimated ASCVD risk in all participants. The performance of the PCEs was similar in cancer survivors and cancer-free participants. IMPLICATIONS FOR CANCER SURVIVORS: Our findings suggest that ASCVD risk prediction tools tailored to survivors of adult cancers may not be needed.

Overweight-years and cancer risk: A prospective study of the association and comparison of predictive performance with body mass index (Atherosclerosis Risk in Communities Study).

Excess body mass index (BMI) is associated with a higher risk of at least 13 cancers, but it is usually measured at a single time point. We tested whether the overweight-years metric, which incorporates exposure time to BMI ≥25 kg/m2 , is associated with cancer risk and compared this with a single BMI measure. We used adulthood BMI readings in the Atherosclerosis Risk in Communities (ARIC) study to derive the overweight-years metric. We calculated associations between the metric and BMI and the risk of cancers using Cox proportional hazards models. Models that either included the metric or BMI were compared using Harrell's C-statistic. We included 13,463 participants, with 3,876 first primary cancers over a mean of 19 years (SD 7) of cancer follow-up. Hazard ratios for obesity-related cancers per standard deviation overweight-years were 1.15 (95% CI: 1.05-1.25) in men and 1.14 (95% CI: 1.08-1.20) in women. The difference in the C-statistic between models that incorporated BMI, or the overweight-years metric was non-significant in men and women. Overweight-years was associated with the risk of obesity-related cancers but did not outperform a single BMI measure in association performance characteristics.

Lower endoscopy, early-onset, and average-onset colon cancer among Medicaid beneficiaries with and without HIV.

BACKGROUND: Studies suggest a lower colorectal cancer (CRC) risk and lower or similar CRC screening among people with HIV (PWH) compared with the general population. We evaluated the incidence of lower endoscopy and average-onset (diagnosed at ≥50) and early-onset (diagnosed at <50) colon cancer by HIV status among Medicaid beneficiares with comparable sociodemographic factors and access to care. METHODS: We obtained Medicaid Analytic eXtract (MAX) data from 2001 to 2015 for 14 states. We included 41 727 243 and 42 062 552 unique individuals with at least 7 months of continuous eligibility for the endoscopy and colon cancer analysis, respectively. HIV and colon cancer diagnoses and endoscopy procedures were identified from inpatient and other nondrug claims. We used Cox proportional hazards regression models to assess endoscopy and colon cancer incidence, controlling for age, sex, race/ethnicity, calendar year and state of enrollment, and comorbidities conditions. RESULTS: Endoscopy and colon cancer incidence increased with age in both groups. Compared with beneficiaries without HIV, PWH had an increased hazard of endoscopy; this association was strongest among those 18-39 years [hazard ratio: 1.85, 95% confidence interval (95% CI) 1.77-1.92] and attenuated with age. PWH 18-39 years also had increased hazard of early-onset colon cancer (hazard ratio: 1.66, 95% CI:1.05-2.62); this association was attenuated after comorbidity adjustment. Hazard ratios were null among all beneficiaries less than 50 years of age. PWH had a lower hazard of average-onset colon cancer compared with those without HIV (hazard ratio: 0.79, 95% CI: 0.66-0.94). CONCLUSION: PWH had a higher hazard of endoscopy, particularly at younger ages. PWH had a lower hazard of average-onset colon cancer. Early-onset colon cancer was higher among the youngest PWH but not associated with HIV overall.

Comparing Cancer Incidence in an Observational Cohort of Medicaid Beneficiaries With and Without HIV, 2001-2015.

BACKGROUND: Life expectancy among people with HIV (PWH) is increasing, making chronic conditions-including cancer-increasingly relevant. Among PWH, cancer burden has shifted from AIDS-defining cancers (ADCs) toward non-AIDS-defining cancers (NADCs). SETTING: We described incidence of cancer in a claims-based cohort of Medicaid beneficiaries. We included 43,426,043 Medicaid beneficiaries (180,058 with HIV) from 14 US states, aged 18-64, with >6 months of enrollment (with no dual enrollment in another insurance) and no evidence of a prveious cancer. METHODS: We estimated cumulative incidence of site-specific cancers, NADCs, and ADCs, by baseline HIV status, using age as the time scale and accounting for death as a competing risk. We compared cumulative incidence across HIV status to estimate risk differences. We examined cancer incidence overall and by sex, race/ethnicity, and calendar period. RESULTS: PWH had a higher incidence of ADCs, infection-related NADCs, and death. For NADCs such as breast, prostate, and colon cancer, incidence was similar or higher among PWH below age 50, but higher among those without HIV by age 65. Incidence of lung and head and neck cancer was always higher for female beneficiaries with HIV, whereas the curves crossed for male beneficiaries. We saw only small differences in incidence trends by race/ethnicity. CONCLUSION: Our findings suggest an increased risk of certain NADCs at younger ages among PWH, even when compared against other Medicaid beneficiaries, and highlight the importance of monitoring PWH for ADCs and NADCs. Future work should explore possible mechanisms explaining the differences in incidence for specific cancer types.