Geographic variation and trends in prevalence of obesity among US adolescents, 2016-2021.

OBJECTIVE: Recent updates of geographic variations, trends, and sociodemographic disparities in obesity prevalence among US adolescents are limited. The study aimed to fill those research gaps. STUDY DESIGN: Serial cross-sectional analysis of the US nationally representative study. METHODS: Data from six cycles of the National Survey of Children's Health (2016, 2017, 2018, 2019, 2020, and 2021) with information on physical health at the national and state level were used. A total of 107,274 adolescents aged 10-17 years old were included with sociodemographic data (age, sex, race/ethnicity, parental education level, and family income) and state of residence. Logistic regression models were used to estimate the odds ratios (ORs) associated with obesity across sociodemographic groups. In addition, ORs were calculated to compare obesity rates between the pandemic period (2020-2021) and the pre-pandemic period (2018-2019) overall and by sociodemographic subgroups. Survey analysis procedures were used to account for complex survey designs to derive representative estimates. RESULTS: From 2016 to 2021, obesity prevalence increased from 16.1% (95% confidence interval [CI], 14.9%-17.4%) to 17.6% (95% CI, 16.4%-18.9%) (P-trend = 0.04). The combined prevalence of obesity varies substantially by state, from 9.34% (95% CI, 6.96%-12.4%; Colorado) to 27.1% (95% CI, 23.1%-31.5%; Mississippi) for adolescents aged 10-13 years and ranged from 9.86% (95% CI, 7.63%-12.7%; Utah) to 22.4% (95% CI, 19.0%-26.1%; West Virginia) for adolescents aged 14-17 years. Except for subgroups male gender and parents with college degrees or above, the prevalence of obesity showed stable trends across sociodemographic subgroups. Compared to the pre-pandemic period, the multivariable-adjusted ORs of obesity were 1.18 (95% CI, 1.06-1.32) for male adolescents, 1.16 (95% CI, 1.04-1.28) for non-Hispanic White adolescents, 1.81 (95% CI, 1.15-2.84) for non-Hispanic Asian adolescents, 1.26 (95% CI, 1.05-1.52) for adolescents whose parents had a high school education, and 1.15 (95% CI, 1.0-1.33) for adolescents whose parents had a college degree or higher. CONCLUSIONS: The prevalence of obesity among US adolescents increased significantly between 2016 and 2021. The prevalence of obesity was relatively high in southern states. Those with low household income, low parental education, or being non-Hispanic Black or Hispanic were also more likely to be obese. Compared to the pre-pandemic period, several groups of adolescents increased their likelihood of obesity during the pandemic period.

A prospective study of type 2 diabetes, metformin use, and risk of breast cancer.

BACKGROUND: Type 2 diabetes (T2D) has been associated with increased breast cancer risk, but commonly prescribed antidiabetic medications such as metformin may reduce risk. Few studies have investigated T2D and medications together in relation to breast cancer. PATIENTS AND METHODS: Data came from 44 541 Sister Study participants aged 35 to 74 years at enrollment (2003-2009) who satisfied eligibility criteria, followed through 15 September 2017. Information on time-varying, self-reported, physician-diagnosed, prevalent and incident T2D, use of antidiabetic medications, and covariates was obtained from baseline and follow-up questionnaires. Incident breast cancers were confirmed with medical records. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated. RESULTS: During follow-up (median, 8.6 years), 2678 breast cancers were diagnosed at least 1 year after enrollment. There were 3227 women (7.2%) with prevalent and 2389 (5.3%) with incident T2D, among whom 61% (n = 3386) were ever treated with metformin. There was no overall association between T2D and breast cancer risk (HR 0.99; 95% CI, 0.87-1.13). However, T2D was associated with increased risk of triple-negative breast cancer (HR 1.40; 95% CI, 0.90-2.16). Compared with not having T2D, T2D with metformin use was not associated with overall breast cancer risk (HR 0.98; 95% CI, 0.83-1.15), but it was associated with decreased risk of estrogen receptor (ER)-positive breast cancer (HR 0.86; 95% CI 0.70-1.05) and increased risk of ER-negative (HR 1.25; 95% CI, 0.84-1.88) and triple-negative breast cancer (HR 1.74; 95% CI, 1.06-2.83). The inverse association with ER-positive cancer was stronger for longer duration (≥10 year) metformin use (HR 0.62; 95% CI, 0.38-1.01; P for trend = 0.09). Results were supported by sensitivity analyses. CONCLUSION: Our findings suggest that associations between T2D and breast cancer may differ by hormone receptor status and that associations between T2D and ER-positive breast cancer may be reduced by long-term metformin use.