Risk of Incident and Fatal Colorectal Cancer After Young-Onset Adenoma Diagnosis: A National Cohort Study

INTRODUCTION

Colorectal cancer (CRC) incidence and mortality rates are increasing in adults aged <50 years. Young-onset adenoma (YOA)-adenoma detected in adults younger than 50 years-may signify increased CRC risk, but this association has not been widely studied. Our aim was to compare the risk of incident and fatal CRC in adults aged <50 years with YOA diagnosis compared with those with a normal colonoscopy.

METHODS

We conducted a cohort study of US Veterans aged 18-49 years who received colonoscopy between 2005 and 2016. The primary exposure of interest was YOA. Primary outcomes included incident and fatal CRC. We used Kaplan-Meier curves to calculate cumulative incident and fatal CRC risk and Cox models to examine relative CRC risk.

RESULTS

The study cohort included 54,284 Veterans aged <50 years exposed to colonoscopy, among whom 13% (n = 7,233) had YOA at start of follow-up. Cumulative 10-year CRC incidence was 0.11% (95% confidence interval [CI]: 0.00%-0.27%) after any adenoma diagnosis, 0.18% (95% CI: 0.02%-0.53%) after advanced YOA diagnosis, 0.10% (95% CI: 0.00%-0.28%) after nonadvanced adenoma diagnosis, and 0.06% (95% CI: 0.02%-0.09%) after normal colonoscopy. Veterans with advanced adenoma had 8-fold greater incident CRC risk than those with normal colonoscopy (hazard ratio: 8.0; 95% CI: 1.8-35.6). Across groups, no differences in fatal CRC risk were observed.

DISCUSSION

Young-onset advanced adenoma diagnosis was associated with 8-fold increased incident CRC risk compared with normal colonoscopy. However, cumulative CRC incidence and mortality at 10 years among individuals with either young onset non-advanced or advanced adenoma diagnosis were both relatively low.

Systematic Review of Prevalence, Risk Factors, and Risk for Metachronous Advanced Neoplasia in Patients With Young-Onset Colorectal Adenoma

BACKGROUND & AIMS

The incidence and mortality of early-onset colorectal cancer (CRC) are increasing. Adenoma detection, removal, and subsequent endoscopic surveillance might modify risk of CRC diagnosed before age 50 years (early-onset CRC). We conducted a systematic review of young-onset adenoma (YOA) prevalence, associated risk factors, and rate of metachronous advanced neoplasia after YOA diagnosis.

METHODS

We performed a systematic search of multiple electronic databases through February 12, 2019 and identified studies of individuals 18 to 49 years old that reported prevalence of adenoma, risk factors for adenoma, and/or risk for metachronous advanced neoplasia. Summary estimates were derived using random effects meta-analysis, when feasible.

RESULTS

The pooled overall prevalence of YOA was 9.0% (95% CI, 7.1%-11.4%), based on 24 studies comprising 23,142 individuals. On subgroup analysis, the pooled prevalence of YOA from autopsy studies was 3.9% (95% CI, 1.9%-7.6%), whereas the prevalence from colonoscopy studies was 10.7% (95% CI, 8.5%-13.5). Only advancing age was identified as a consistent risk factor for YOA, based on 4 studies comprising 78,880 individuals. Pooled rate of metachronous advanced neoplasia after baseline YOA diagnosis was 6.0% (95% CI, 4.1%-8.6%), based on 3 studies comprising 1493 individuals undergoing follow-up colonoscopy, with only 1 CRC case reported. Overall, few studies reported metachronous advanced neoplasia and no studies evaluated whether routine surveillance colonoscopy decreases risk of CRC.

CONCLUSIONS

In a systematic review, we estimated the prevalence of YOA to be 9% and to increase with age. Risk for metachronous advanced neoplasia after YOA diagnosis is estimated to be 6%. More research is needed to understand the prevalence, risk factors, and risk of CRC associated with YOA.

The Role of Hypoxia-Inducible Factor 1 in Mild Cognitive Impairment

Neuroinflammation and reactive oxygen species are thought to mediate the pathogenesis of Alzheimer's disease (AD), suggesting that mild cognitive impairment (MCI), a prodromal stage of AD, may be driven by similar insults. Several studies document that hypoxia-inducible factor 1 (HIF-1) is neuroprotective in the setting of neuronal insults, since this transcription factor drives the expression of critical genes that diminish neuronal cell death. HIF-1 facilitates glycolysis and glucose metabolism, thus helping to generate reductive equivalents of NADH/NADPH that counter oxidative stress. HIF-1 also improves cerebral blood flow which opposes the toxicity of hypoxia. Increased HIF-1 activity and/or expression of HIF-1 target genes, such as those involved in glycolysis or vascular flow, may be an early adaptation to the oxidative stressors that characterize MCI pathology. The molecular events that constitute this early adaptation are likely neuroprotective, and might mitigate cognitive decline or the onset of full-blown AD. On the other hand, prolonged or overwhelming stressors can convert HIF-1 into an activator of cell death through agents such as Bnip3, an event that is more likely to occur in late MCI or advanced Alzheimer's dementia.

Effect modification by race-ethnicity of environmental tobacco smoke exposure on airway inflammation in US children

BACKGROUND

Asthma mortality and morbidity are higher in black than in white children. Fractional exhaled nitric oxide (FeNO) is a noninvasive biomarker of eosinophilic airway inflammation. Identification of differences in the effect of environmental tobacco smoke (ETS) on airway inflammation by race and ethnicity from a large sample is needed.

OBJECTIVE

To estimate a racial difference in association with ETS and FeNO.

METHODS

Data from the 2007 to 2012 National Health and Nutrition Examination Survey were analyzed to compare associations of ETS and FeNO levels in US black and other children. No ETS exposure was defined as a serum cotinine level lower than 0.05 ng/mL and ETS exposure was defined as a serum cotinine level of at least 0.05 ng/mL. FeNO was measured using a device that relies on an electrochemical sensor. Analyses took the complex survey design into account.

RESULTS

The analytic sample was formed by 5,473 participants (6-11 years old, n = 2,385; 12-19 years old, n = 3,088) with complete data on demographics, serum cotinine levels, and 2 reproducible FeNO measurements. In weighted linear regression analyses at 6 to 11 years, the interaction term for ETS and black race was not significant (P = .15). At 12 to 19 years, the interaction term was significant (P = .03) in an analysis of all racial groups. In race-specific models, the coefficient for ETS exposure in blacks was -0.033 and that in others was -0.175, ie, ETS exposure was associated with a greater decrease in FeNO in non-blacks than in blacks.

CONCLUSION

There was no evidence at 6 to 11 years of age for an effect modification by race of the association between ETS and FeNO. At 12 to 19 years, the data suggested an effect modification.

Comparison of surgical bypass with angioplasty and stenting of superficial femoral artery disease

OBJECTIVE

To evaluate the contemporary outcome of femoral-popliteal bypass compared with angioplasty and stenting in patients with symptomatic peripheral arterial disease (PAD) in terms of patency and reintervention rates.

METHODS

We identified all patients evaluated at the Johns Hopkins Bayview Medical Center with the presumptive diagnosis of PAD from September 2005 to September 2010. In this group, we selected all symptomatic patients after failing medical management who received percutaneous transluminal angioplasty/stenting of the superficial femoral artery or femoral-popliteal bypass. We compared the overall patency and reintervention rates between the two groups as well as patency within TransAtlantic Inter-Society Consensus (TASC) II subgroups. Descriptive analyses were performed using χ(2) and two-sided t-tests. The Mann-Whitney U test was used to compare distributions of continuous variables and the Fisher exact test for categorical variables. Cox proportional hazard model was used to examine the treatment effect within each lesion type, using bypass as the reference group.

RESULTS

Out of 1237 patients evaluated at Johns Hopkins Bayview Medical Center for PAD from September 2005 to September 2010, we identified 104 symptomatic patients who received percutaneous transluminal angioplasty/stenting of the superficial femoral artery or femoral-popliteal bypass after failing medical management. There were 61 male patients (56%), and the mean age was 68 years in both groups. Both treatment groups had similar risk factors. Overall, 77% of patients with TASC II A and B lesions underwent angioplasty and stenting, whereas 73% of patients with TASC C and D lesions underwent bypass (P < .01). The primary patency at 24 months was better for the stent group 67% (95% confidence interval [CI], 0.52-0.78) vs bypass group 49% (95% CI, 0.32-0.64; P = .05). The rate of reintervention within the 2-year period was higher in the bypass group compared with the stent group (54% vs 31%; P = .02). TASC A and B lesions combined demonstrated a reduced hazard of patency failure compared with TASC C or D lesions combined (hazard ratio, 2.42; 95% CI, 1.26, 4.65; P < .01).

CONCLUSIONS

This is the first study that documents higher reintervention rates for femoral-popliteal bypass compared with angioplasty and stenting. We believe that the main reason for this finding is the fact that the bypass patients had significantly more advanced disease. This, emphasizes that one must consider the patient population undergoing intervention when comparing revascularization procedures. A prospective randomized trial is needed to determine the overall better treatment option.