| 1. |
- Archambault, Alexi N., et al.
(author)
-
Cumulative Burden of Colorectal Cancer Associated Genetic Variants Is More Strongly Associated With Early-Onset vs Late-Onset Cancer
- 2020
-
In: Gastroenterology. - : Elsevier BV. - 0016-5085 .- 1528-0012. ; 158:5, s. 1274-1286.e12
-
Journal article (peer-reviewed)abstract
- BACKGROUND & AIMS: Early-onset colorectal cancer (CRC, in persons younger than 50 years old) is increasing in incidence; yet, in the absence of a family history of CRC, this population lacks harmonized recommendations for prevention. We aimed to determine whether a polygenic risk score (PRS) developed from 95 CRC-associated common genetic risk variants was associated with risk for early-onset CRC.METHODS: We studied risk for CRC associated with a weighted PRS in 12,197 participants younger than 50 years old vs 95,865 participants 50 years or older. PRS was calculated based on single nucleotide polymorphisms associated with CRC in a large-scale genome-wide association study as of January 2019. Participants were pooled from 3 large consortia that provided clinical and genotyping data: the Colon Cancer Family Registry, the Colorectal Transdisciplinary Study, and the Genetics and Epidemiology of Colorectal Cancer Consortium and were all of genetically defined European descent. Findings were replicated in an independent cohort of 72,573 participants.RESULTS: Overall associations with CRC per standard deviation of PRS were significant for early-onset cancer, and were stronger compared with late-onset cancer (P for interaction = .01); when we compared the highest PRS quartile with the lowest, risk increased 3.7-fold for early-onset CRC (95% CI 3.28-4.24) vs 2.9-fold for late-onset CRC (95% CI 2.80-3.04). This association was strongest for participants without a first-degree family history of CRC (P for interaction = 5.61 x 10(-5)). When we compared the highest with the lowest quartiles in this group, risk increased 4.3-fold for early-onset CRC (95% CI 3.61-5.01) vs 2.9-fold for late-onset CRC (95% CI 2.70-3.00). Sensitivity analyses were consistent with these findings.CONCLUSIONS: In an analysis of associations with CRC per standard deviation of PRS, we found the cumulative burden of CRC-associated common genetic variants to associate with early-onset cancer, and to be more strongly associated with early-onset than late-onset cancer, particularly in the absence of CRC family history. Analyses of PRS, along with environmental and lifestyle risk factors, might identify younger individuals who would benefit from preventive measures.
|
|
| 2. |
- Leong, Karen S. W., et al.
(author)
-
Associations of Prenatal and Childhood Antibiotic Exposure With Obesity at Age 4 Years
- 2020
-
In: JAMA Network Open. - : AMER MEDICAL ASSOC. - 2574-3805. ; 3:1
-
Journal article (peer-reviewed)abstract
- Importance Although antibiotics are associated with obesity in animal models, the evidence in humans is conflicting. Objective To assess whether antibiotic exposure during pregnancy and/or early childhood is associated with the development of childhood obesity, focusing particularly on siblings and twins. Design, Setting, and Participants This cross-sectional national study included 284 & x202f;211 participants (132 & x202f;852 mothers and 151 & x202f;359 children) in New Zealand. Data analyses were performed for 150 & x202f;699 children for whom data were available, 30 & x202f;696 siblings, and 4188 twins using covariate-adjusted analyses, and for 6249 siblings and 522 twins with discordant outcomes using fixed-effects analyses. Data analysis was performed November 2017 to March 2019. Exposure Exposure to antibiotics during pregnancy and/or early childhood. Main Outcomes and Measures The main outcome is odds of obesity at age 4 years. Anthropometric data from children born between July 2008 and June 2011 were obtained from the B4 School Check, a national health screening program that records the height and weight of 4-year-old children in New Zealand. These data were linked to antibiotics (pharmaceutical records) dispensed to women before conception and during all 3 trimesters of pregnancy and to their children from birth until age 2 years. Results The overall study population consisted of 132 & x202f;852 mothers and 151 & x202f;359 children (77 & x202f;610 [51.3%] boys) who were aged 4 to 5 years when their anthropometrical measurements were assessed. Antibiotic exposure was common, with at least 1 course dispensed to 35.7% of mothers during pregnancy and 82.3% of children during the first 2 years of life. Results from covariate-adjusted analyses showed that both prenatal and early childhood exposures to antibiotics were independently associated with obesity at age 4 years, in a dose-dependent manner. Every additional course of antibiotics dispensed to the mothers yielded an adjusted odds ratio (aOR) of obesity in their children (siblings) of 1.02 (95% CI, 0.99-1.06), which was similar to the odds across pregnancy for the whole population (aOR, 1.06; 95% CI, 1.04-1.07). For the child's exposure, the aOR for the association between antibiotic exposure and obesity was 1.04 (95% CI, 1.03-1.05) among siblings and 1.05 (95% CI, 1.02-1.09) among twins. However, fixed-effects analyses of siblings and twins showed no associations between antibiotic exposure and obesity, with aORs of 0.95 (95% CI, 0.90-1.00) for maternal exposure, 1.02 (95% CI, 0.99-1.04) for child's exposure, and 0.91 (95% CI, 0.81-1.02) for twins' exposure. Conclusions and Relevance Although covariate-adjusted analyses demonstrated an association between antibiotic exposure and odds of obesity, further analyses of siblings and twins with discordant outcomes showed no associations. Thus, these discordant results likely reflect unmeasured confounding factors. Question Is antibiotic exposure during pregnancy and/or during early childhood associated with the development of childhood obesity? Findings This cross-sectional national study of 284 & x202f;211 participants (132 & x202f;852 mothers and 151 & x202f;359 children) in New Zealand found that both prenatal and early childhood exposures to antibiotics were independently associated with obesity at age 4 years in a dose-dependent manner. However, fixed-effects analyses of siblings and twins with discordant outcomes showed no associations between antibiotic exposure and obesity. Meaning Although judicious use of antibiotics is necessary, antibiotics are unlikely to be a major contributor to childhood obesity. This cross-sectional study of mothers and their children in New Zealand assesses whether exposure to antibiotics during pregnancy and/or early childhood is associated with the development of childhood obesity.
|
|
