Duration of Adulthood Overweight, Obesity, and Cancer Risk in the Women's Health Initiative: A Longitudinal Study from the United States

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.

Trends in breast cancer mortality attributable to metabolic risks in Chinese women from 1990 to 2019: an age-period-cohort analysis

Objective

Metabolic risks (MRs) are the primary determinants of breast cancer (BC) mortality among women. This study aimed to examine the changing trends in BC mortality associated with MRs and explore how they related to age, time period, and birth cohorts in Chinese women aged 25 and above.

Methods

Data were sourced from the Global Burden of Disease Study 2019 (GBD2019). The BC mortality trajectories and patterns attributable to MRs were assessed using Joinpoint regression. The age-period-cohort (APC) model was employed to evaluate cohort and time period effects.

Results

The age-standardized mortality rate (ASMR) of BC mortality linked to MRs displayed an escalating trend from 1990 to 2019, demonstrating an average annual percentage change (AAPC) of 1.79% (95% CI: 1.69~1.87). AAPCs attributable to high fasting plasma glucose (HFPG) and high body mass index (HBMI) were 0.41% (95% CI: 0.32~0.53) and 2.75% (95% CI: 2.68~2.82), respectively. APC analysis revealed that BC mortality due to HBMI in women aged 50 and above showed a rise with age and mortality associated with HFPG consistently demonstrated a positive correlation with age. The impact of HBMI on BC mortality significantly outweighed that of HFPG. The risk of BC mortality linked to HBMI has steadily increased since 2005, while HFPG demonstrated a trend of initial increase followed by a decrease in the period effect. Regarding the cohort effect, the relative risk of mortality was greater in the birth cohort of women after the 1960s of MRs on BC mortality, whereas those born after 1980 displayed a slight decline in the relative risk (RR) associated with BC mortality due to HBMI.

Conclusion

This study suggests that middle-aged and elderly women should be considered as a priority population, and control of HBMI and HFPG should be used as a primary tool to control metabolic risk factors and effectively reduce BC mortality.

Trajectories of body mass index across the lifecourse and associations with post-menopausal breast cancer by estrogen receptor status

BACKGROUND

Associations between a high body mass index (BMI) at single timepoints during child- and adulthood and risks of post-menopausal breast cancer are well-established, but associations with BMI across the lifecourse remains largely unknown. Therefore, we examined whether lifecourse BMI trajectories were associated with risks of post-menopausal breast cancer overall and by estrogen receptor (ER) status.

METHODS

We included 6698 Danish women born 1930-1946. Information on BMI at ages 6-15 years came from the Copenhagen School Health Records Register, and information on BMI at ages 20, 30, 40, 50 and/or 50-64 years came from the Diet, Cancer and Health cohort. Breast cancer cases (n = 577) were identified in the Danish Breast Cancer Cooperative Group database. Six BMI trajectories were identified using latent class trajectory modelling. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox regression models.

RESULTS

Compared to women with a trajectory characterized by an average BMI gain across life, women with the two trajectories with steep increases in BMI during childhood and adolescence that thereafter largely stabilized, had lower risks of post-menopausal breast cancer and ER-positive tumors. The adjusted HRs for ER-positive tumors were 0.67 (95% CI: 0.47-0.95) and 0.68 (95% CI: 0.46-1.01), respectively. In contrast, women with a trajectory with a low gain in BMI during childhood and adolescence followed by a subsequent steep increase during adulthood, had higher risks of post-menopausal breast cancer and ER-positive tumors when compared to women with an average BMI gain. The adjusted HR for ER-positive tumors was 1.28 (95% CI: 0.98-1.67).

CONCLUSIONS

Our findings suggest that the timing of excess gain in BMI across the lifecourse impacts subsequent post-menopausal breast cancer risks. Thus, the BMI development across life is likely useful in the identification of women at increased risks of post-menopausal breast cancer.

The prognostic impact of body mass index in breast cancer according to tumor subtype

PURPOSE

Several studies demonstrated that obesity and underweight were negatively associated with outcomes of breast cancer. However, the results are still controversial, and the impact of body mass index (BMI) on distant metastasis-free survival (MFS), which might directly affect mortality, was less well evaluated. Our study aimed to verify the prognostic effect of BMI in breast cancer.

METHODS

A retrospective analysis of 504 patients with stage I-III breast cancer who underwent surgery from January 2005 to December 2013 was performed. The patients were divided into three groups according to preoperative BMI: underweight <18.5 kg/m2, normal weight 18.5-24.9 kg/m2, and overweight ≥25 kg/m2. The association between body weight status and breast cancer recurrence was analyzed. Subgroup analysis by tumor subtype according to receptor status was also performed.

RESULTS

The median follow-up period was 88 months. For disease recurrence, histologic grade and human epidermal growth factor receptor 2 (HER2)-positivity were independent prognostic factors in multivariate analysis. Stage, histologic grade, HER2-positivity, and BMI status were independent prognostic factors for distant metastasis. In survival analysis, overweight and underweight were significant predisposing factors for MFS, but not for disease-free survival (DFS). In the estrogen receptor (ER)-positive group, overweight and underweight patients had significantly worse DFS and MFS than normal weight patients. In the ER-negative or HER2-positive group, BMI status had no significant association with DFS and MFS.

CONCLUSION

The prognostic role of BMI on the survival outcomes of patients with breast cancer was different by tumor subtype. In ER-positive patients, overweight and underweight statuses had a negative prognostic effect on DFS and MFS, respectively.

Trends in weight change patterns across life course among US adults, 1988-2018: population-based study

BACKGROUND

To examine trends in weight change patterns from young adulthood through midlife to late adulthood and their sex and racial/ethnic disparities among US adults from 1988 to 2018.

METHODS

A total of 48,969 participants from the National Health and Nutrition Examination Survey 1988-1994 and 2001-2018 were included.

RESULTS

The age-adjusted prevalence of stable non-obesity between young adulthood and midlife declined significantly from 84.1% (95 CI, 82.9-85.3%) in 1988-1994 to 68.7% (67.1-70.2%) in 2013-2018, and between midlife and late adulthood from 71.2% (69.2-73.1%) to 52.4% (50.5-54.2%). The magnitude of increase in the prevalence of weight gain from young adulthood to midlife (from 10.8% [9.9-11.6%] in 1988-1994 to 21.2% [20-22.3%] in 2013-2018; P < 0.001 for trend) was greater than that from midlife to late adulthood (from 14.1% [12.9-15.3%] to 17.2% [16.2-18.1%]; P = 0.002 for trend). The magnitude of increase in the prevalence of stable obesity from young adulthood to midlife (from 3.9% [3.1-4.8%] in 1988-1994 to 9.2% [8.2-10.3%] in 2013-2018; P < 0.001 for trend) was smaller than that from midlife to late adulthood (from 11.2% [10.1-12.2%] to 24.8% [23.3-26.3%]; P < 0.001 for trend). The declining trends in the prevalence of stable non-obesity and increasing trends in the prevalence of weight gain and stable obesity from young adulthood through midlife to late adulthood were also observed for all sex and race/ethnicity subgroups. The magnitude of decrease in the prevalence of stable non-obesity, and the magnitude of increase in the prevalence of weight gain from young adulthood through midlife to late adulthood were greater in men than in women (all P for interaction < 0.01). Weight gain patterns for those aged ≥ 65 years were substantially different from the younger age groups.

CONCLUSIONS

More young people born in later years are encountering obesity and accumulate greater obesity exposure across their lives than young people born in earlier years.

Lifetime Body Weight Trajectories and Risk of Renal Cell Cancer: A Large U.S. Prospective Cohort Study

BACKGROUND

Body mass index (BMI) is a known risk factor for renal cell cancer (RCC), but data are limited as to the effect of lifetime exposure to excess body weight.

METHODS

Using the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (N = 138,614, 527 incident RCCs), we identified several anthropometric measures to capture the lifetime BMI patterns: (i) BMI at specific ages; (ii) adulthood BMI trajectories; (iii) cumulative exposure to overweight/obesity denoted as weighted years of living overweight/obese (WYO); and (iv) weight change during each age span. We conducted multivariable Cox model to quantify the association between each anthropometric metric and incident RCC.

RESULTS

A higher BMI at ages 20 and 50 and at baseline was associated with a greater hazard of RCC. Compared with individuals who retained normal BMI throughout adulthood, we observed an increased hazard of RCC for BMI trajectory of progressing from normal BMI to overweight [HR, 1.49; 95% confidence interval (CI), 1.19-1.87], from normal BMI to obesity (HR, 2.22; 95% CI, 1.70-2.90), and from overweight to obesity (HR, 2.78; 95% CI, 1.81-4.27). Compared with individuals who were never overweight (WYO = 0), elevated HRs were observed among individuals who experienced low (HR, 1.31; 95% CI, 0.99-1.74), medium (HR, 1.57; 95% CI, 1.20-2.05), and high (HR, 2.10; 95% CI, 1.62-2.72) WYO tertile. Weight gain of ≥10 kg was associated with increased RCC incidence for each age span.

CONCLUSIONS

Across the lifespan, being overweight/obese, weight gain, and higher cumulative exposure to excess weight were all associated with increased RCC risk.

IMPACT

It is important to avoid weight gain and assess BMI from a life-course perspective to reduce RCC risk.

Trajectories of body mass index in adulthood and risk of subtypes of postmenopausal breast cancer

BACKGROUND

Body fatness is a dynamic exposure throughout life. To provide more insight into the association between body mass index (BMI) and postmenopausal breast cancer, we aimed to examine the age at onset, duration, intensity, and trajectories of body fatness in adulthood in relation to risk of breast cancer subtypes.

METHODS

Based on self-reported anthropometry in the prospective Norwegian Women and Cancer Study, we calculated the age at onset, duration, and intensity of overweight and obesity using linear mixed-effects models. BMI trajectories in adulthood were modeled using group-based trajectory modeling. We used Cox proportional hazards models to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for the associations between BMI exposures and breast cancer subtypes in 148,866 postmenopausal women.

RESULTS

A total of 7223 incident invasive postmenopausal breast cancer cases occurred during follow-up. Increased overweight duration and age at the onset of overweight or obesity were associated with luminal A-like breast cancer. Significant heterogeneity was observed in the association between age at overweight and overweight duration and the intrinsic-like subtypes (pheterogeneity 0.03). Compared with women who remained at normal weight throughout adulthood, women with a descending BMI trajectory had a reduced risk of luminal A-like breast cancer (HR 0.54, 95% CI 0.33-0.90), whereas women with ascending BMI trajectories were at increased risk (HR 1.09; 95% CI 1.01-1.17 for "Normal-overweight"; HR 1.20; 95% CI 1.07-1.33 for "Normal-obesity"). Overweight duration and weighted cumulative years of overweight and obesity were inversely associated with luminal B-like breast cancer.

CONCLUSIONS

In this exploratory analysis, decreasing body fatness from obesity in adulthood was inversely associated with overall, hormone receptor-positive and luminal A-like breast cancer in postmenopausal women. This study highlights the potential health benefits of reducing weight in adulthood and the health risks associated with increasing weight throughout adult life. Moreover, our data provide evidence of intrinsic-like tumor heterogeneity with regard to age at onset and duration of overweight.

Multifaceted effects of obesity on cancer immunotherapies: Bridging preclinical models and clinical data

Obesity, defined by excessive body fat, is a highly complex condition affecting numerous physiological processes, such as metabolism, proliferation, and cellular homeostasis. These multifaceted effects impact cells and tissues throughout the host, including immune cells as well as cancer biology. Because of the multifaceted nature of obesity, common parameters used to define it (such as body mass index in humans) can be problematic, and more nuanced methods are needed to characterize the pleiotropic metabolic effects of obesity. Obesity is well-accepted as an overall negative prognostic factor for cancer incidence, progression, and outcome. This is in part due to the meta-inflammatory and immunosuppressive effects of obesity. Immunotherapy is increasingly used in cancer therapy, and there are many different types of immunotherapy approaches. The effects of obesity on immunotherapy have only recently been studied with the demonstration of an "obesity paradox", in which some immune therapies have been demonstrated to result in greater efficacy in obese subjects despite the direct adverse effects of obesity and excess body fat acting on the cancer itself. The multifactorial characteristics that influence the effects of obesity (age, sex, lean muscle mass, underlying metabolic conditions and drugs) further confound interpretation of clinical data and necessitate the use of more relevant preclinical models mirroring these variables in the human scenario. Such models will allow for more nuanced mechanistic assessment of how obesity can impact, both positively and negatively, cancer biology, host metabolism, immune regulation, and how these intersecting processes impact the delivery and outcome of cancer immunotherapy.

Longitudinal body mass index and cancer risk: a cohort study of 2.6 million Catalan adults

Single body mass index (BMI) measurements have been associated with increased risk of 13 cancers. Whether life course adiposity-related exposures are more relevant cancer risk factors than baseline BMI (ie, at start of follow-up for disease outcome) remains unclear. We conducted a cohort study from 2009 until 2018 with population-based electronic health records in Catalonia, Spain. We included 2,645,885 individuals aged ≥40 years and free of cancer in 2009. After 9 years of follow-up, 225,396 participants were diagnosed with cancer. This study shows that longer duration, greater degree, and younger age of onset of overweight and obesity during early adulthood are positively associated with risk of 18 cancers, including leukemia, non-Hodgkin lymphoma, and among never-smokers, head and neck, and bladder cancers which are not yet considered as obesity-related cancers in the literature. Our findings support public health strategies for cancer prevention focussing on preventing and reducing early overweight and obesity.

Glucose metabolic reprogramming and its therapeutic potential in obesity-associated endometrial cancer

Endometrial cancer (EC) is a common gynecological cancer that endangers women health. Although substantial progresses of EC management have been achieved in recent years, the incidence of EC still remains high. Obesity has been a common phenomenon worldwide that increases the risk of EC. However, the mechanism associating obesity and EC has not been fully understood. Metabolic reprogramming as a remarkable characteristic of EC is currently emerging. As the primary factor of metabolic syndrome, obesity promotes insulin resistance, hyperinsulinemia and hyperglycaemia. This metabolic disorder remodels systemic status, which increases EC risk and is related with poor prognosis. Glucose metabolism in EC cells is complex and mediated by glycolysis and mitochondria to ensure energy requirement. Factors that affect glucose metabolism may have an impact on EC initiation and progression. In this study, we review the glucose metabolic reprogramming of EC not only systemic metabolism but also inherent tumor cell metabolism. In particular, the role of glucose metabolic regulation in malignant properties of EC will be focused. Understanding of metabolic profile and glucose metabolism-associated regulation mechanism in EC may provide novel perspective for treatment.

High Body Mass Index Was Associated With Human Epidermal Growth Factor Receptor 2-Positivity, Histological Grade and Disease Progression Differently by Age

Background

Breast cancer is the most commonly occurring cancer among women. The relationship between the obesity paradox and breast cancer is still unclear. The goal of this study is to elucidate the association between high body mass index (BMI) and pathological findings by age.

Methods

We collected BMI information pertinent to breast cancer patients from the Gene Expression Omnibus (GEO) database. We use a BMI of 25 as a boundary, and those greater than 25 are defined as high BMI. Besides, we segregated the patients based on age into two age groups: < 55 years, and > 55 years. In this study, R × C Chi-square for trend and binary logistic regression was used to estimate the odds ratios (ORs) and corresponding 95% confidence intervals (CIs).

Results

Higher BMI was associated with less breast cancer incidence in females younger than 55 years of age (OR = 0.313, CI: 0.240 - 0.407). High BMI was associated with human epidermal growth factor receptor 2 (HER2) positivity in breast cancer patients of less than 55 years (P < 0.001), but not in the older patients. High BMI was associated with histological grade lower than 2 in the breast cancer patients older than 55 years, but not in younger patients (OR = 0.288, CI: 0.152 - 0.544). Besides, high BMI was associated with worse progression-free survival in younger breast cancer patients, but not in older patients (P < 0.05).

Conclusions

Our results described a significant relationship between breast cancer incidence and BMI at different ages and benefit breast cancer patients to implement strategies to control their BMI for reducing the recurrence and distant recurrence.

Childhood body mass index trajectories, adult-onset type 2 diabetes, and obesity-related cancers

BACKGROUND

Elevated childhood body mass index (BMI), commonly examined as a "once-only" value, increases the risk of cancer and type 2 diabetes (T2D) in adulthood. Continuous exposure to adiposity during childhood may further increase cancer risk. We examined whether longitudinal childhood BMI trajectories were associated with adult obesity-related cancer and the role of adult-onset T2D in these associations.

METHODS

Five sex-specific latent class BMI trajectories were generated for 301 927 children (149 325 girls) aged 6-15 years from the Copenhagen School Health Records Register. Information on obesity-related cancers and T2D was obtained from national health registers. Incidence rate ratios (IRR), cumulative incidences, and confidence intervals (CI) were estimated using Poisson regressions.

RESULTS

Compared with the average childhood BMI trajectory (containing approximately 40% of individuals), the rate of obesity-related cancer (excluding breast cancer) increased with higher childhood BMI trajectories among women. The highest rates occurred in the overweight (IRR = 1.27, 95% CI = 1.17 to 1.38) and obesity (IRR = 1.79, 95% CI = 1.53 to 2.08) BMI trajectories. Similar patterns were observed among men. In contrast, women with the obesity childhood BMI trajectory had the lowest rate of pre- and postmenopausal breast cancer (IRR = 0.59, 95% CI = 0.43 to 0.80, and IRR = 0.41, 95% CI = 0.30 to 0.57, respectively). For all trajectories, the cumulative risk of obesity-related cancer increased with adult-onset T2D.

CONCLUSION

Consistent childhood overweight or obesity may increase the rates of adult obesity-related cancer and decrease the rates of breast cancer. Adult-onset T2D conferred additional risk for obesity-related cancer, but the effect did not differ across childhood BMI trajectories.

Twelve-Year Trajectory of Disease Burden and Mortality by Obesity Level in Korea: Analysis of the National Health Insurance Service Database

INTRODUCTION

Despite increases in obesity prevalence, awareness of obesity as a disease requiring active treatment remains lacking in Korea. We investigated differences in medical problems and expenditures and mortality across obesity categories using 12-year data from the National Health Insurance Service.

MATERIALS AND METHODS

Individuals aged 40-79 years who underwent medical examinations during 2003-2004 (n = 415,201) were divided based on Asian body mass index (kg/m²) criteria: normal weight (18.5 to < 23.0, 36.4%), overweight (23.0 to < 25.0, 28.3%), obesity (25.0 to < 30.0, 32.5%), and severe obesity (≥ 30.0, 2.8%). Medical problems and expenditures were fitted to linear mixed models. Mortality was analyzed via Cox proportional-hazards model.

RESULTS

More severe obesity was associated with a higher rate of medical problems, relative to normal weight: coefficient = 0.31 (95% confidence interval [CI], 0.30-0.32) for overweight, 0.61 (0.60-0.61) for obesity, and 1.07 (1.04-1.09) for severe obesity. A similar association was observed for medical expenditure: coefficient = 8.85 (95%CI, 6.80-10.89) for overweight, 20.04 (18.07-22.01) for obesity, and 48.76 (43.66-53.86) for severe obesity. Relative to overweight participants, those with normal weight and severe obesity exhibited a higher mortality risk (hazard ratio [HR] 1.21 [95%CI, 1.18-1.25] for normal; 1.27 [1.19-1.36] for severe obesity). In age-specific analyses, mortality risk was the highest for participants with severe obesity, aged < 60 years (HR, 1.58 [95%CI, 1.41-1.77]).

CONCLUSION

Disease burden including medical problems and expenditure, and mortality in middle-aged adults, increased proportionally to the degrees of obesity. Health policies and medical systems aimed at reducing the burden of obesity may help reduce the burden of disease on society.

Association of childhood and adolescence obesity with incidence and mortality of adulthood cancers. A systematic review and meta-analysis

BACKGROUND

Prevalence and subsequent conditions of childhood and adolescent obesity are increasing. It has been seen that obesity in youth is associated with adulthood cancer. This systematic review and meta-analysis aimed to determine the pooled association of childhood obesity with cancers in adulthood.

METHODS

In this systematic review, international electronic databases such as Scopus, PubMed, Web of Science, and EMBASE were searched using relevant keywords until February 2022. All Cohort studies assessing the association of childhood and adolescent obesity (under 18 years old) with the incidence and mortality of all types of cancers were included. Two independent reviewers screened and carried out the quality assessment of included studies. Between-studies heterogeneity was assessed using the I squared and Cochran's Q tests. Random/fixed-effect meta-analyses were used to pool the appropriate effect sizes (Hazard ratios (HR)).

RESULTS

Overall, 46 studies were found to be relevant and were included in this study. Based on the random-effects model meta-analysis, childhood obesity increased the hazard of cancer incidence and mortality in adulthood by 33% (HR: 1.33, 95%CI (1.25, 1.41)) and by 28% (HR: 1.28, 95%CI (1.13, 1.42)), respectively. In the subgroups meta-analysis, the HR of childhood obesity and adulthood cancer incidence mortality in women was higher than in men (HR=1.39, 95%CI (1.25, 1.53) vs HR= 1.20, 95%CI (1.07, 1.32)) and (HR= 1.40, 95%CI (1.10, 1.69) vs HR=1.20, 95%CI (1.04, 1.36)) respectively.

CONCLUSION

This study found that obesity in childhood and adolescence is associated with a significant increase in the incidence and mortality of cancers in adulthood. Prevention of childhood obesity, in addition to its short-term beneficial effects, can reduce the burden of cancer in adulthood. The data sets of this study are present in the Tables of the current manuscript. Moreover this study was registered online in PROSPERO (registration code: CRD42022331958).

SYSTEMIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/Prospero/, identifier CRD42022331958.

Self-Reported Early and Later Life Weight and the Risk of All-Cause Mortality in Older Adults

OBJECTIVES

The extent to which body weight in early adulthood is associated with late-life mortality risk is unclear. This study aimed to determine the association between body mass index (BMI) in early adulthood (at 18 years of age) and older age (70 years and over), and the risk of mortality in later life.

DESIGN

Secondary analysis of the ASPREE Longitudinal Study of Older Persons (ALSOP).

SETTING, PARTICIPANTS

Data were from 14,853 relatively healthy community-dwelling Australians aged ≥ 70 years when enrolled in the study.

MEASUREMENTS

Self-reported weight at age ≥ 70 years and recalled weight at age 18 years were collected at ALSOP study baseline. Height was measured with a stadiometer and was used for calculation of BMI at both timepoints. BMI at each timepoint was defined as: underweight, normal weight, overweight and obese. Individuals were categorised into one of five 'lifetime' BMI groups: normal weight (BMI between 18.5 and 24.9 at both times), overweight (25.0-29.9 at either or both times), obesity to non-obese (≥30.0 at age 18 and <30.0 ≥ 70 years), non-obese to obesity (<30.0 at age 18 and ≥30.0 at age ≥ 70 years), and early and later life obesity (≥30.0 at both times).

RESULTS

During a median 4.7 years follow-up, 715 deaths occurred. Obesity at 18 years, but not in older age (p=0.44), was significantly associated with the risk of mortality in later life, even after accounting for current health status (HR: 2.35, 95% CI: 1.53-3.58, p<0.001). Compared with participants with normal BMI at both time points, being obese at both time points was associated with increased mortality risk (HR=1.99, 95% CI: 1.04-3.81, p=0.03), and the risk was even greater for individuals who were obese at 18 years but were no longer obese in older age (HR=2.92, 95% CI: 1.65-5.16, p<0.001), in fully adjusted models. Participants who were normal weight at 18 years and were obese in later life, did not have an increased mortality risk (p=0.78).

CONCLUSIONS

Obesity in early adulthood, and obesity in both early and later life, were associated with increased mortality risk in later life. This highlights the importance of preventing obesity in early adulthood and maintaining a normal weight over an adult lifespan.

Value of endometrial thickness for the detection of endometrial cancer and atypical hyperplasia in asymptomatic postmenopausal women

BACKGROUND

The role of transvaginal sonography (TVS) in screening endometrial cancer and hyperplasia is significant in postmenopausal women. The objective of this study is to determine the endometrium thickness (ET) cut-off to distinguish premalignancy and malignancy in asymptomatic postmenopausal women.

METHODS

We retrospectively evaluated data of 968 eligible patients among 2537 asymptomatic postmenopausal women with ET ≥ 5 mm examined by TVS who were subjected to hysteroscopy and endometrial biopsy between January 1, 2017, and June 30, 2020 in an urban tertiary specialized hospital in China. The patients were divided into two groups according to the pathology outcomes: benign, and atypical hyperplasia (AH) and endometrial carcinoma (EC). The risk factors and the optimal cut-off of ET for detecting AH and EC were determined by logistic regression analysis and receiver operating characteristic curve.

RESULTS

2537 patients were offered hysteroscopy during a 42-month period. Finally, 968 patients were included for further analysis. Of these, 8 (0.8%) women were diagnosed with EC and 5 (0.5%) women with AH. The mean ET of AH and EC group was substantially higher than that in benign group (10.4 mm vs. 7.7 mm, P < 0.05). ET was significantly correlated with AH and EC shown by logistic regression analysis with an odds ratio (OR) of 1.252 (95% confidence interval [CI] 1.107-1.416, P < 0.001). The optimal cut-off value for AH and EC was found to be 8 mm with the maximum AUC of 0.715 (95% CI 0.686-0.743, P < 0.001), with a sensitivity of 0.846, a specificity of 0.609, positive likelihood ratio (LR+) of 2.164 and negative likelihood ratio (LR-) of 0.253.

CONCLUSION

An ET cut-off of ≥ 8 mm shows a reasonable performance to detect AH and EC in asymptomatic postmenopausal women, thereby avoiding more invasive endometrial biopsy.

Prediagnostic BMI trajectories in relation to pancreatic cancer risk in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial

OBJECTIVE

It remains elusive whether prediagnostic BMI trajectory is associated with pancreatic cancer.

METHODS

This study investigated this question among 145,489 participants who gave rise to 696 incident cases of pancreatic cancer over a median follow-up of 12 years in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. At baseline, participants were asked to recall their weight at ages 20, 50, and 55 to 74 years (at enrollment), as well as their height.

RESULTS

At age 50 years, people with obesity had a significantly increased risk of pancreatic cancer compared with those with a normal weight after adjustment for confounders (hazard ratio [95% CI]: 1.27 [1.01-1.60]). Individuals who had overweight at age 20 years experienced a marginally significant elevated risk of pancreatic cancer (hazard ratio [95% CI]: 1.22 [0.99-1.50]). Compared with individuals who maintained a steady normal weight during follow-up, no significantly altered risk of pancreatic cancer was observed for those whose weight status changed from normal weight to overweight, from normal weight to obesity, and from overweight to obesity.

CONCLUSIONS

The present study revealed that prediagnostic adulthood BMI trajectory was not associated with pancreatic cancer risk, but overweight at young adulthood and obesity at middle adulthood may confer an elevated risk of this malignancy.

The timing of adiposity and changes in the life course on the risk of cancer

Excess body weight has been established as a risk factor for at least twelve cancer sites, though questions remain as to the timing of associations for adiposity and cancer risk throughout the life course. We conducted a narrative review summarizing existing evidence to provide insights into the complex timing relationship between adiposity and risk of seven common obesity-related cancers. We considered five types of studies, including traditional epidemiologic studies examining adiposity at different time points, studies examining weight gain in specific life phases, studies examining weight loss over a period including from bariatric surgery, life course trajectory analysis, and Mendelian randomization studies. The results showed that lifetime excess body weight is associated with increased risk of cancers of endometrium, colorectum, liver, kidney, and pancreas. Early life obesity is one of the strongest risk factors for pancreatic cancer but less directly important than adult obesity for endometrial and kidney cancer. Interestingly, heavy weight during childhood, adolescence, and early adulthood is protective against pre- and postmenopausal breast cancer and possibly advanced prostate cancer. It is apparent that preventing weight gain later in adulthood would likely reduce risk of many cancers, including postmenopausal breast cancer, endometrial cancer, colorectal cancer (especially in men), liver cancer, kidney cancer, and probably advanced prostate cancer. Furthermore, weight loss even late in life may confer benefits for cancers of breast, endometrium, colorectum, and liver among patients with obesity, as mostly demonstrated by studies of bariatric surgery. Overall, maintaining a healthy weight throughout the life course will help prevent a large number of cancers.

Obesity and Breast Cancer Risk: The Oncogenic Implications of Metabolic Dysregulation

CONTEXT

Breast cancer is increasing in prevalence in parallel with rising rates of obesity worldwide. Obesity is recognized as a leading modifiable risk factor for the development of breast cancer; however, this association varies considerably by clinicopathologic features, and the underlying mechanisms are complex.

EVIDENCE ACQUISITION

Pubmed literature search using combinations of "obesity," "breast cancer risk," "diet," "exercise," "weight gain," "weight loss," "adipose tissue inflammation," "crown-like structure," "immune markers," "metformin," "gliflozins," "SGLT-2i," "GLP1-RA," and related terms.

EVIDENCE SYNTHESIS

Elevated body mass index and weight gain are associated with increased risk of postmenopausal, hormone receptor-positive breast cancer. Emerging evidence suggests that adverse measures of body composition in individuals of any weight can also confer increased breast cancer risk. Mechanistically, various factors including altered adipokine balance, dysfunctional adipose tissue, dysregulated insulin signaling, and chronic inflammation contribute to tumorigenesis. Weight loss and more specifically fat mass loss through lifestyle and pharmacologic interventions improve serum metabolic and inflammatory markers, sex hormone levels, and measures of breast density, suggesting a link to decreased breast cancer risk.

CONCLUSION

Incorporating markers of metabolic health and body composition measures with body mass index can capture breast cancer risk more comprehensively. Further studies of interventions targeting body fat levels are needed to curb the growing prevalence of obesity-related cancer.

Impact of cumulative body mass index and cardiometabolic diseases on survival among patients with colorectal and breast cancer: a multi-centre cohort study

BACKGROUND

Body mass index (BMI) and cardiometabolic comorbidities such as cardiovascular disease and type 2 diabetes have been studied as negative prognostic factors in cancer survival, but possible dependencies in the mechanisms underlying these associations remain largely unexplored. We analysed these associations in colorectal and breast cancer patients.

METHODS

Based on repeated BMI assessments of cancer-free participants from four European countries in the European Prospective Investigation into Cancer and nutrition (EPIC) study, individual BMI-trajectories reflecting predicted mean BMI between ages 20 to 50 years were estimated using a growth curve model. Participants with incident colorectal or breast cancer after the age of 50 years were included in the survival analysis to study the prognostic effect of mean BMI and cardiometabolic diseases (CMD) prior to cancer. CMD were defined as one or more chronic conditions among stroke, myocardial infarction, and type 2 diabetes. Hazard ratios (HRs) and confidence intervals (CIs) of mean BMI and CMD were derived using multivariable-adjusted Cox proportional hazard regression for mean BMI and CMD separately and both exposures combined, in subgroups of localised and advanced disease.

RESULTS

In the total cohort of 159,045 participants, there were 1,045 and 1,620 eligible patients of colorectal and breast cancer. In colorectal cancer patients, a higher BMI (by 1 kg/m2) was associated with a 6% increase in risk of death (95% CI of HR: 1.02-1.10). The HR for CMD was 1.25 (95% CI: 0.97-1.61). The associations for both exposures were stronger in patients with localised colorectal cancer. In breast cancer patients, a higher BMI was associated with a 4% increase in risk of death (95% CI: 1.00-1.08). CMDs were associated with a 46% increase in risk of death (95% CI: 1.01-2.09). The estimates and CIs for BMI remained similar after adjustment for CMD and vice versa.

CONCLUSIONS

Our results suggest that cumulative exposure to higher BMI during early to mid-adulthood was associated with poorer survival in patients with breast and colorectal cancer, independent of CMD prior to cancer diagnosis. The association between a CMD diagnosis prior to cancer and survival in patients with breast and colorectal cancer was independent of BMI.

Body mass index and cancer mortality in patients with incident type 2 diabetes: A population-based study of adults in England

AIMS

We evaluated the relationship between body mass index (BMI) and cancer mortality in incident type 2 diabetes.

METHODS

We used the Clinical Practice Research Datalink GOLD (1998-2015), linked with the Office of National Statistics mortalities, and derived an incident type 2 diabetes cohort (N = 176 886; aged 30-85 years). We determined BMI ±12 months diabetes diagnosis. The primary outcome was cancer mortality, categorized into deaths from obesity-related cancers (ORCs) and non-ORCs. Secondary outcomes were site-specific cancer mortality and main causes of deaths [cancer, cardiovascular disease (CVD), non-cancer non-CVD]. We developed gender-specific Cox models and expressed risk as hazard ratios and 95% confidence intervals, stratified by smoking status.

RESULTS

With 886 850 person-years follow-up, 7593 cancer deaths occurred. Among women who never smoked, there were positive associations between BMI and deaths from endometrial (hazard ratios per 5 kg/m² : 1.43; 95% confidence interval 1.26-1.61). Among men, associations between BMI and ORC mortality were inverse but attenuated towards null among never smokers and excluding deaths in the first 2 years. In men, the proportion of CVD deaths increased from 36.8% in BMI category 22.5 to 24.9 kg/m² to 43.6% in BMI category ≥40 kg/m² (p < .001).

CONCLUSIONS

We found some relationships between BMI and cancer mortality in patients with type 2 diabetes, but interpretations need to account for smoking status, reverse causality and deaths from CVD.

Effects of a group-based weight management programme on anxiety and depression: A randomised controlled trial (RCT)

OBJECTIVES

The aim was to investigate the impact of a group-based weight management programme on symptoms of depression and anxiety compared with self-help in a randomised controlled trial (RCT).

METHOD

People with overweight (Body Mass Index [BMI]≥28kg/m2) were randomly allocated self-help (n = 211) or a group-based weight management programme for 12 weeks (n = 528) or 52 weeks (n = 528) between 18/10/2012 and 10/02/2014. Symptoms were assessed using the Hospital Anxiety and Depression Scale, at baseline, 3, 12 and 24 months. Linear regression modelling examined changes in Hospital Anxiety and Depression Scale between trial arms.

RESULTS

At 3 months, there was a -0.6 point difference (95% confidence interval [CI], -1.1, -0.1) in depression score and -0.1 difference (95% CI, -0.7, 0.4) in anxiety score between group-based weight management programme and self-help. At subsequent time points there was no consistent evidence of a difference in depression or anxiety scores between trial arms. There was no evidence that depression or anxiety worsened at any time point.

CONCLUSIONS

There was no evidence of harm to depression or anxiety symptoms as a result of attending a group-based weight loss programme. There was a transient reduction in symptoms of depression, but not anxiety, compared to self-help. This effect equates to less than 1 point out of 21 on the Hospital Anxiety and Depression Scale and is not clinically significant.

Obesity during childhood is associated with higher cancer mortality rate during adulthood: the i3C Consortium

BACKGROUND

In high-income countries, cancer is the leading cause of death among middle-aged adults. Prospective data on the effects of childhood risk exposures on subsequent cancer mortality are scarce.

METHODS

We examined whether childhood body mass index (BMI), blood pressure, glucose and lipid levels were associated with adult cancer mortality, using data from 21,012 children enrolled aged 3-19 years in seven prospective cohort studies from the U.S., Australia, and Finland that have followed participants from childhood into adulthood. Cancer mortality (cancer as a primary or secondary cause of death) was captured using registries.

RESULTS

354 cancer deaths occurred over the follow-up. In age-, sex, and cohort-adjusted analyses, childhood BMI (Hazard ratio [HR], 1.13; 95% confidence interval [CI] 1.03-1.24 per 1-SD increase) and childhood glucose (HR 1.22; 95%CI 1.01-1.47 per 1-SD increase), were associated with subsequent cancer mortality. In a multivariable analysis adjusted for age, sex, cohort, and childhood measures of fasting glucose, total cholesterol, triglycerides, and systolic blood pressure, childhood BMI remained as an independent predictor of subsequent cancer mortality (HR, 1.24; 95%CI, 1.03-1.49). The association of childhood BMI and subsequent cancer mortality persisted after adjustment for adulthood BMI (HR for childhood BMI, 1.35; 95%CI 1.12-1.63).

CONCLUSIONS

Higher childhood BMI was independently associated with increased overall cancer mortality.

Excess Body Fatness during Early to Mid-Adulthood and Survival from Colorectal and Breast Cancer: A Pooled Analysis of Five International Cohort Studies

BACKGROUND

Here, we explore the association between excess weight during early to mid-adulthood and survival in patients diagnosed with breast and colorectal cancer, using a pooled analysis of five cohort studies and study participants from 11 countries.

METHODS

Participant-level body mass index (BMI) trajectories were estimated by fitting a growth curve model using over 2 million repeated BMI measurements from close to 600,000 cohort participants. Cumulative measures of excess weight were derived. Data from over 23,000 patients with breast and colorectal cancer were subsequently analyzed using time-to-event models for death with the date of diagnosis as start of follow-up. Study-specific results were combined through a random effect meta-analysis.

RESULTS

We found a significant dose-response relationship (P trend = 0.013) between the average BMI during early and mid-adulthood and death from breast cancer, with a pooled HR of 1.31 (1.07-1.60) and the time to death shortened by 16% for average BMI above 25 kg/m2 compared with average BMI less than or equal to 22.5 kg/m2, respectively. Similar results were found for categories of cumulative time spent with excess weight. There was no association between excess body fatness during early to mid-adulthood and death in patients with colorectal cancer.

CONCLUSIONS

Excess body fatness during early to mid-adulthood is associated not only with an increased risk of developing cancer, but also with a lower survival in patients with breast cancer.

IMPACT

Our results emphasize the importance of public health policies aimed at reducing overweight during adulthood and inform future studies on the relationship between excess weight and cancer outcomes.

A review of research on the intersection between breast cancer and cardiovascular research in the Women's Health Initiative (WHI)

Both obesity and metabolic syndrome are linked to increased incidence of type 2 diabetes, cardiovascular disease (CVD), and cancers of the breast (post-menopausal), and other obesity-related cancers. Over the past 50 years, the worldwide prevalence of obesity and metabolic syndrome has increased, with a concomitant higher incidence of associated co-morbidities and mortality. The precise mechanism linking metabolic syndrome to increased cancer incidence is incompletely understood, however, individual components of metabolic syndrome have been linked to increased breast cancer incidence and worse survival. There is a bidirectional relationship between the risk of CVD and cancer due to a high burden of shared risk factors and higher rates of CVD among cancer survivors, which may be impacted by the pro-inflammatory microenvironment associated with metabolic syndrome and cancer-directed therapies. The Women's Health Initiative (WHI) is an excellent resource to study a dual relationship between cancer and CVD (cardio-oncology) with extensive information on risk factors and long-term outcomes. The purpose of this review is to provide an overview of research on cardio-oncology conducted utilizing WHI data with focus on studies evaluating both breast cancer and CVD including shared risk factors and outcomes after cancer. The review also includes results on other obesity related cancers which were included in the analyses of breast cancer, articles looking at cancer after heart disease (reverse cardio-oncology) and the role of Clonal Hematopoiesis of Indeterminate Potential (CHIP) as a shared risk factor between CVD and cancer. A summary of pertinent WHI literature helps to delineate the direction of future research evaluating the relationship between CVD and other cancer sites, and provides information on the opportunity for other novel analyses within the WHI.

Adult lifetime body mass index trajectories and endometrial cancer risk

OBJECTIVE

To identify body mass index (BMI) trajectories in adult life and to examine their association with endometrial cancer (EC) risk, also exploring whether relations differ by HRT use.

DESIGN

Pooled analysis of two case control studies.

SETTING

Italy and Switzerland.

POPULATION

A total of 458 EC cases and 782 controls.

METHODS

We performed a latent class growth model in order to identify homogenous BMI trajectories over 6 decades of age, with a polynomial function of age. Odds Ratios (ORs) and the corresponding 95% confidence intervals (CI) for EC risk were derived through a multiple logistic regression model, correcting for classification error.

MAIN OUTCOME MEASURES

The relation of BMI trajectories with endometrial cancer.

RESULTS

We identified 5 BMI trajectories. Compared with women in the 'Normal weight-stable' trajectory, a reduction by about 50% in the risk of EC emerged for those in the 'Underweight increasing to normal weight' (95% CI=0.28-0.99). The 'Normal weight increasing to overweight' and the 'Overweight-stable' trajectories were associated to, respectively, an excess of 3% (95% CI=0.66-1.60) and of 71% (95% CI= 1.12-2.59) in cancer risk. The OR associated to the trajectory 'Overweight increasing to obese' was 2.03 (95% CI= 1.31-3.13). Stronger effects emerged among HRT never users (OR= 2.19 for the 'Overweight-stable' trajectory and OR=2.49 for the 'Overweight increasing to obese' trajectory).

CONCLUSIONS

Our study suggests that longer exposure to overweight and obesity across lifetime is associated with an increased risk of endometrial cancer. Weight during adulthood also appears to play an important role.

Obesity Duration, Severity, and Distribution Trajectories and Cardiovascular Disease Risk in the Atherosclerosis Risk in Communities Study

Background Research examining the role of obesity in cardiovascular disease (CVD) often fails to adequately consider heterogeneity in obesity severity, distribution, and duration. Methods and Results We here use multivariate latent class mixed models in the biracial Atherosclerosis Risk in Communities study (N=14 514; mean age=54 years; 55% female) to associate obesity subclasses (derived from body mass index, waist circumference, self-reported weight at age 25, tricep skinfold, and calf circumference across up to four triennial visits) with total mortality, incident CVD, and CVD risk factors. We identified four obesity subclasses, summarized by their body mass index and waist circumference slope as decline (4.1%), stable/slow decline (67.8%), moderate increase (24.6%), and rapid increase (3.6%) subclasses. Compared with participants in the stable/slow decline subclass, the decline subclass was associated with elevated mortality (hazard ratio [HR] 1.45, 95% CI 1.31, 1.60, P<0.0001) and with heart failure (HR 1.41, 95% CI 1.22, 1.63, P<0.0001), stroke (HR 1.53, 95% CI 1.22, 1.92, P=0.0002), and coronary heart disease (HR 1.36, 95% CI 1.14, 1.63, P=0.0008), adjusting for baseline body mass index and CVD risk factor profile. The moderate increase latent class was not associated with any significant differences in CVD risk as compared to the stable/slow decline latent class and was associated with a lower overall risk of mortality (HR 0.85, 95% CI 0.80, 0.90, P<0.0001), despite higher body mass index at baseline. The rapid increase latent class was associated with a higher risk of heart failure versus the stable/slow decline latent class (HR 1.34, 95% CI 1.10, 1.62, P=0.004). Conclusions Consideration of heterogeneity and longitudinal changes in obesity measures is needed in clinical care for a more precision-oriented view of CVD risk.

Durable Response to Vemurafenib and Cobimetinib for the Treatment of BRAF-Mutated Metastatic Melanoma in Routine Clinical Practice

Background

The combination of BRAF and MEK inhibitors delays the onset of resistance and provides more sustained and dramatic responses in comparison with a BRAF inhibitor in monotherapy. The objective of the study was to evaluate the effectiveness of the combination therapy with vemurafenib/cobimetinib in terms of durability, and to describe differential characteristics in patients associated to durable responses in real-world settings.

Patients and Methods

Retrospective, observational, cross-sectional, multicenter study involving 41 patients with advanced melanoma harboring a BRAF^V600 mutation who initiated a combination therapy with vemurafenib/cobimetinib between May 2018 and March 2019. Participants were differentiated regarding the durability of the response: durable (complete response, CR, or a partial response, PR, for at least 12 months) and non-durable (stable disease, SD, progressive disease, PD, or CR/PR <12 months). Secondary endpoints included treatment adherence, labor productivity, anxiety/depression, and safety profile.

Results

During the combination therapy, 12 patients (29.3%) had a CR, 19 a PR (46.3%), 5 showed SD (12.2%), and 5 had PD. A total of 12 patients (29.3%) were considered as achieving a durable response and 29 (70.7%) as a non-durable one. Practically all sociodemographic and clinical characteristics were similar between patients. Body mass index was the only differential factor (with higher body mass index achieving a non-durable response). The treatment adherence was 100% in patients with durable response and 66.7% in those with non-durable.

Conclusion

The combination treatment with vemurafenib/cobimetinib results in an important impact on long-term survival, leading to a steady CR in one-third of the patients.

Adherence to a Mediterranean-Style Dietary Pattern and Cancer Risk in a Prospective Cohort Study

A Mediterranean-style diet is a healthy eating pattern that may benefit cancer risk, but evidence among Americans is scarce. We examined the prospective association between adherence to such a diet pattern and total cancer risk. A Mediterranean-style dietary pattern (MSDP) score was derived from a semi-quantitative food frequency questionnaire at exam 5 (1991–1995). Subjects included 2966 participants of the Framingham Offspring Study who were free of prevalent cancer. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs), adjusting for demographic, lifestyle, and anthropometric measures. Cox-models were also used to examine effect modification by lifestyle and anthropometric measures. During 18 years of median follow-up, 259 women and 352 men were diagnosed with cancer. Women with moderate or higher adherence to the MSDP had ≥25% lower risks of cancer than women with the lowest MSDP (HR (moderate vs. lowest): 0.71, 95% CI: 0.52–0.97 and HR (highest vs. lowest): 0.74; 95% CI: 0.55–0.99). The association between MSDP score and cancer risk in men was weaker except in non-smokers. Beneficial effects of the MSDP in women were stronger among those who were not overweight. In this study, higher adherence to MSDP was associated with lower cancer risk, especially among women.

Cumulative obesity exposure increases the risk of kidney cancer: a longitudinal nationwide cohort study

Obesity is one of the most important prognostic factors of kidney cancer. However, little is known regarding the cumulative impacts of obesity on kidney cancer risk. We aimed to analyze the dose- and time-dependent impact of obesity on kidney cancer risk using the Korean National Health Insurance System database. This longitudinal nationwide cohort study used data from the Korean National Health Insurance System database between 2012 and 2013. In total, 3,102,240 participants who received annual health examination more than four times consecutively were included in the final analysis. The primary endpoint was newly diagnosed kidney cancer according to the dose- and time-dependent impact of obesity. Dose-dependent impact was measured using body mass index (BMI) and waist circumference (WC), and time-dependent impact was measured using general and abdominal cumulative obesity exposure (gCOE and aCOE). COE was defined as the number of years since obesity diagnosis during the exposure period. We identified 1,831 participants with newly diagnosed kidney cancer (median follow-up: 4.3 years). The hazard ratios (HRs) for kidney cancer increased significantly alongside BMI and WC. The HRs for kidney cancer increased significantly in the higher gCOE groups (P for trend <0.001) as follows: 1 (1.33, 95% confidence intervals: 1.10-1.60), 2 (1.33, 1.08-1.63), 3 (1.55, 1.30-1.85), and 4 (1.82, 1.64-2.03) years. Similar trends were observed for aCOE (P for trend <0.001) as follows: 1 (1.42, 1.23-1.64), 2 (1.71, 1.46-2.02), 3 (1.76, 1.48-2.08), and 4 (2.11, 1.84-2.42) years. Risks of kidney cancer related to COE were much more pronounced in participants with the following characteristics: younger than 65 years old, male gender, diabetes, hypertension, and dyslipidemia. Longer COE was associated with an increased risk of kidney cancer in the Korean population. Participants with prolonged obesity and metabolic syndrome need active surveillance for kidney cancer.

Targeting obesity-related dysfunction in hormonally driven cancers

Obesity is a risk factor for at least 13 different types of cancer, many of which are hormonally driven, and is associated with increased cancer incidence and morbidity. Adult obesity rates are steadily increasing and a subsequent increase in cancer burden is anticipated. Obesity-related dysfunction can contribute to cancer pathogenesis and treatment resistance through various mechanisms, including those mediated by insulin, leptin, adipokine, and aromatase signalling pathways, particularly in women. Furthermore, adiposity-related changes can influence tumour vascularity and inflammation in the tumour microenvironment, which can support tumour development and growth. Trials investigating non-pharmacological approaches to target the mechanisms driving obesity-mediated cancer pathogenesis are emerging and are necessary to better appreciate the interplay between malignancy, adiposity, diet and exercise. Diet, exercise and bariatric surgery are potential strategies to reverse the cancer-promoting effects of obesity; trials of these interventions should be conducted in a scientifically rigorous manner with dose escalation and appropriate selection of tumour phenotypes and have cancer-related clinical and mechanistic endpoints. We are only beginning to understand the mechanisms by which obesity effects cell signalling and systemic factors that contribute to oncogenesis. As the rates of obesity and cancer increase, we must promote the development of non-pharmacological lifestyle trials for the treatment and prevention of malignancy.

Secondhand smoke exposure, diabetes, and high BMI are risk factors for uterine cervical cancer: a cross-sectional study from the Korea national health and nutrition examination survey (2010-2018)

Background

Human papilloma virus infection and tobacco smoking are the major risk factors for cervical cancer. There are limited studies searching other risk factors for cervical cancer and the results are not consistent. This study investigated the relations between cervical cancer and possible risk factors, including secondhand cigarette smoke exposure, diabetes, body mass index (BMI), and work schedule.

Methods

In this cross-sectional study, 29,557 women completed a cervical cancer questionnaire and were selected using 2010–2018 data from the Korea National Health and Nutrition Examination Survey. Details in secondhand smoke exposure, diabetes, BMI, and work schedule were assessed with participants’ health interviews and health-related surveys.

Results

Two hundred sixty-two women (0.89%) in the sample were diagnosed with cervical cancer. Domestic secondhand smoke exposure, diabetes, and high BMI significantly increased cervical cancer risk. Respective odds ratios and 95% confidence intervals were: 1.547 (1.042–2.297), 2.156 (1.535–3.027), and 1.036 (1.006–1.067). Weekly work hours, and work schedule were not significantly related to cervical cancer incidence.

Conclusion

Among Korean women, passive exposure to cigarette smoke at home, diabetes, and high BMI increase risk for cervical cancer.

The Triple Health Threat of Diabetes, Obesity, and Cancer-Epidemiology, Disparities, Mechanisms, and Interventions

Obesity and type 2 diabetes are both chronic, relapsing, progressive diseases that are recognized as risk factors for the development of multiple types of cancer. In a recent symposium titled "Hitting A Triple-Diabetes, Obesity, and the Emerging Links to Cancer Risk," convened by The Obesity Society during ObesityWeek 2019, experts in the field presented the current science and highlighted existing research gaps. Topics included (1) the epidemiology of obesity and diabetes and their links to cancer risk; (2) racial and ethnic differences in obesity, diabetes, and cancer risk; (3) biological mechanisms common to obesity and diabetes that may increase cancer risk; and (4) innovative interventions that can be used to prevent the development of cancers related to obesity and diabetes. This report provides an overview of the symposium and describes key research gaps and pressing questions in need of answers to advance the field. The collective burden of obesity, diabetes, and cancer represents one of the largest public health challenges of the century. Although the symposium was titled "hitting a triple," it was recognized that being able to disrupt the linkages among obesity, diabetes, and cancer would be a "grand slam" for public health and medicine.

The Role of Mendelian Randomization Studies in Deciphering the Effect of Obesity on Cancer

Associations of obesity have been established for at least 11 cancer sites in observational studies, though some questions remain as to causality, strength of associations, and timing of associations throughout the life course. In recent years, Mendelian randomization (MR) has provided complementary information to traditional approaches, but the validity requires that the genetic instrumental variables be causally related to cancers only mediated by the exposure. We summarize and evaluate existing evidence from MR studies in comparison with conventional observational studies to provide insights into the complex relationship between obesity and multiple cancers. MR studies further establish the causality of adult obesity with esophageal adenocarcinoma, cancers of the colorectum, endometrium, ovary, kidney, and pancreas, as well as the inverse association of early life obesity with breast cancer. MR studies, which might account for lifelong adiposity, suggest that the associations in observational studies typically based on single measurement may underestimate the magnitude of the association. For lung cancer, MR studies find a positive association with obesity, supporting that the inverse association observed in some conventional observational studies likely reflects reverse causality (loss of lean body mass before diagnosis) and confounding by smoking. However, MR studies have not had sufficient power for gallbladder cancer, gastric cardia cancer, and multiple myeloma. In addition, more MR studies are needed to explore the effect of obesity at different time points on postmenopausal breast cancer and aggressive prostate cancer.

Associations of specific-age and decade recall body mass index trajectories with obesity-related cancer

Background

Excess body fatness, commonly approximated by a one-off determination of body mass index (BMI), is associated with increased risk of at least 13 cancers. Modelling of longitudinal BMI data may be more informative for incident cancer associations, e.g. using latent class trajectory modelling (LCTM) may offer advantages in capturing changes in patterns with time. Here, we evaluated the variation in cancer risk with LCTMs using specific age recall versus decade recall BMI.

Methods

We obtained BMI profiles for participants from the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. We developed gender-specific LCTMs using recall data from specific ages 20 and 50 years (72,513 M; 74,837 W); decade data from 30s to 70s (42,113 M; 47,352 W) and a combination of both (74,106 M, 76,245 W). Using an established methodological framework, we tested 1:7 classes for linear, quadratic, cubic and natural spline shapes, and modelled associations for obesity-related cancer (ORC) incidence using LCTM class membership.

Results

Different models were selected depending on the data type used. In specific age recall trajectories, only the two heaviest classes were associated with increased risk of ORC. For the decade recall data, the shapes appeared skewed by outliers in the heavier classes but an increase in ORC risk was observed. In the combined models, at older ages the BMI values were more extreme.

Conclusions

Specific age recall models supported the existing literature changes in BMI over time are associated with increased ORC risk. Modelling of decade recall data might yield spurious associations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08226-4.

Cumulative exposure to premenopausal obesity and risk of postmenopausal cancer: A population-based study in Icelandic women

Obesity, often assessed at one point in time, is an established risk factor of several types of cancer, however, associations with cumulative exposure to obesity across the life course are not well understood. We investigated the relationship between combined measures of duration and intensity of premenopausal overweight and obesity and the incidence of postmenopausal breast, endometrial, and colorectal cancers in Icelandic women. Body mass index (BMI) trajectories between ages 20 and 50 of 88,809 women from the Cancer Detection Clinic Cohort were predicted using growth curve models. Indicators of overweight and obesity duration and intensity were computed and their association with risk of postmenopausal breast, endometrial, and colorectal cancers was examined using multivariate Cox models for subjects followed-up beyond the age of 50 (n = 67,488). During a mean follow-up of 17 years, incident events of 3,016 postmenopausal breast, 410 endometrial and 987 colorectal cancers were ascertained. Each 0.1 kg/m2 per year increase in BMI between ages 20 and 50 was positively associated with risks of postmenopausal breast, endometrium and colorectal cancers with hazard ratios equal to 1.09 (95% Confidence Interval (CI):1.04-1.13), 1.31 (95% CI: 1.18-1.44) and 1.10 (95% CI: 1.00-1.21), respectively. Compared to women who were never obese, cumulative BMI × years of obesity were linearly positively associated with risk of endometrial cancer, whereas the association with breast cancer was initially positive, but leveled off with increasing cumulative BMI × years. Cumulative exposure to obesity may provide additional insights into the etiology of cancer and should be considered in future studies that assess obesity-cancer relationships.

Exposure to light at night (LAN) and risk of obesity: A systematic review and meta-analysis of observational studies

BACKGROUND

There is emerging evidence of the association between light at night (LAN) exposure and weight gain.

OBJECTIVE

We aim to conduct a systematic review and meta-analysis of observational studies on the association between LAN exposure and risk of obesity in human subjects.

METHODS

Peer-reviewed observational studies were systematically searched from MEDLINE (EBSCO), Academic Search Complete (EBSCO), CINAHL Plus (EBSCO) and PubMed up to December 24, 2019. Random-effects models were developed to estimate the associations between LAN exposure and weight-related outcomes of overweight and obesity as measured by body mass index (BMI), waist circumference, waist-hip-ratio and waist-to-height-ratio. The I² statistic was used to assess the degree of heterogeneity across studies. The National Toxicology Program's Office of Health Assessment and Translation (OHAT) risk of bias rating tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) guideline were respectively employed to assess the risk of bias and to appraise the quality of the generated evidence.

RESULTS

A total of 12 studies (three with longitudinal and nine of cross-sectional design) published between 2003 and 2019 were included for systematic review, while seven of them fulfilling the inclusion/exclusion criteria were included in the meta-analysis. A higher LAN exposure was significantly associated with 13% higher odds of overweight (BMI≥25 kg/m²) (Summary Odds Ratio; SOR: 1.13, 95% CI: 1.10-1.16) with low heterogeneity (I² = 27.27%), and 22% higher odds of obesity (BMI≥30 kg/m²) (SOR: 1.22, 95% CI: 1.07-1.38) with substantial heterogeneity (I² = 85.96%). Stratifying analyses by the levels of measurement of LAN exposures (macro-, meso- and micro-levels) and time of LAN measurement (including before and while sleeping) consistently produced robust estimates, with higher exposure to LAN being positively associated with poorer weight outcomes. Assessment of risk of bias identified substantial detection bias for exposure, with over half of the pooled studies employing subjective LAN measures. The overall evidence of the association between LAN exposure and risk of obesity was rated as 'moderate' as per the GRADE guideline.

CONCLUSIONS

Exposure to LAN was reported to be a significant risk factor for overweight and obesity. Prospectively designed future studies with objectively measured multi-level LAN exposures and weight outcomes are required.

Physical activity trajectories following gynecological cancer: results from a prospective, longitudinal cohort study

BACKGROUND

Participating in physical activity after a diagnosis of cancer is associated with reduced morbidity and improved outcomes. However, declines in, and low levels of, physical activity are well documented in the broader cancer population, but with limited evidence following gynecological cancer.

OBJECTIVE

To describe physical activity levels from before and up to 2 years after gynecological cancer surgery; to explore the relationship between physical activity patterns and quality of life; and to describe characteristics associated with physical activity trajectories post-gynecological cancer.

METHODS

Women with gynecological cancer (n=408) participated in a prospective study that assessed physical activity and quality of life pre-surgery (baseline), at 6 weeks, and 3, 6, 9, 12, 15, 18 and 24 months post-surgery. Validated questionnaires were used to assess physical activity (Active Australia Survey) and quality of life outcomes (Functional Assessment of Cancer Therapy-General). Generalized estimating equation modeling, group-based trajectory analysis, and analysis of variance were used to identify physical activity levels over time, to categorize women into physical activity trajectory groups, and to assess the relationship between physical activity levels and quality of life, respectively.

RESULTS

Women had a mean±SD age of 60±11.4 years at diagnosis, with the majority diagnosed with endometrial cancer (n=235, 58%) or stage I disease (n=241, 59%). Most women (80%) started with and maintained low levels of physical activity (1-10 metabolic equivalent task hours per week), reported no physical activity throughout the follow-up period, or reduced physical activity levels over time. Only 19% of women maintained or doubled physical activity levels, so that by 24 months post-diagnosis they were engaging in sufficient levels of physical activity. Women with endometrial cancer (58% of the sample) were more likely to be overweight or obese and to report low levels of physical activity or none at all. Higher physical activity levels were associated with higher quality of life (p<0.05).

CONCLUSION

The low baseline and surveillance levels of physical activity show that the vast majority of gynecological cancer survivors have the ability to improve their physical activity levels. Integration of physical activity advice and support into standard care could lead to gains in quality of life during gynecological cancer survivorship.

LncRNA CTBP1-AS2 regulates miR-216a/ PTEN to suppress ovarian cancer cell proliferation

Background

We analyzed TCGA dataset and observed the downregulation of CTBP1-AS2 in ovarian cancer (OC), while the function of CTBP1-AS2 has only been investigated in diabetes and cardiomyocyte hypertrophy, but not in cancer biology. We therefore analyzed the involvement of CTBP1-AS2 in OC.

Result

We found that CTBP1-AS2 was downregulated in OC and predicted poor survival. CTBP1-AS2 in luciferase activity assay interacted with miR-216a, while overexpression of CTBP1-AS2 and miR-216a had no significant effects on the expression of each other. However, increased expression level of PTEN, a target of miR-216a, was observed after CTBP1-AS2 overexpression. Increased proliferation rate of OC cells was observed after the overexpression of miR-216a. CTBP1-AS2 and PTEN overexpression resulted in the reduced proliferation rate of OC cells and reduced effects of miR-216a overexpression.

Conclusion

CTBP1-AS2 regulates miR-216a/PTEN to suppress OC cell proliferation.

An Ecological Momentary Assessment Study Investigating Self-efficacy and Outcome Expectancy as Mediators of Affective and Physiological Responses and Exercise Among Endometrial Cancer Survivors

BACKGROUND

Previous studies have shown affective and physiological states in response to exercise as predictors of daily exercise, yet little is known about the mechanism underlying such effects.

PURPOSE

To examine the mediating effects of self-efficacy and outcome expectancy on the relationships between affective and physiological responses to exercise and subsequent exercise levels in endometrial cancer survivors.

METHODS

Ecological momentary assessment (EMA) surveys were delivered up to eight 5- to 7-day periods over 6 months. Participants (n = 100) rated their affective and physiological states before and after each exercise session (predictors) and recorded their self-efficacy and outcome expectancy each morning (mediators). Exercise (outcome) was based on self-reported EMA surveys and accelerometer measures. A 1-1-1 multilevel mediation model was used to disaggregate the within-subject (WS) and between-subject (BS) effects.

RESULTS

At the WS level, a more positive affective state after exercise was associated with higher self-efficacy and positive outcome expectation the next day, which in turn was associated with higher subsequent exercise levels (ps < .05). At the BS level, participants who typically had more positive affective and experienced less intense physiological sensation after exercise had higher average self-efficacy, which was associated with higher average exercise levels (ps < .05).

CONCLUSIONS

In endometrial cancer survivors, affective experience after exercise, daily self-efficacy and positive outcome expectation help explain the day-to-day differences in exercise levels within-person. Findings from this study highlight potentials for behavioral interventions that target affective experience after exercise and daily behavioral cognitions to promote physical activity in cancer survivors' everyday lives.

A longitudinal study of prediagnostic metabolic biomarkers and the risk of molecular subtypes of colorectal cancer

Body fatness increases the risk of colorectal cancer (CRC). Insulin resistance and altered adipokines are potential mechanisms, but previous biomarker studies have been inconsistent. Intertumoral heterogeneity might provide an explanation. We investigated insulin, C-peptide, adiponectin, and leptin in relation to CRC molecular subtypes using a nested case-control design (1010 cases, 1010 matched controls, median 12.3 years from baseline to CRC diagnosis) from the population-based Northern Sweden Health and Disease Study. Repeated samples were available from 518 participants. Risks of CRC and subtypes, defined by tumor BRAF and KRAS mutations and microsatellite instability (MSI) status, were estimated using conditional logistic regression and linear mixed models. Higher C-peptide and lower adiponectin were associated with increased CRC risk (odds ratios per standard deviation increase (95% CI): 1.11 (1.01, 1.23) and 0.91 (0.83, 1.00), respectively), though weakened when adjusted for body mass index. Insulin and leptin were not associated with CRC risk. Within-individual time trajectories were similar in cases and controls, and no subtype-specific relationships were identified (all P_{heterogeneity} > 0.1). Adiponectin was weakly inversely associated with the risk of KRAS-mutated (P = 0.08) but not BRAF-mutated or KRAS/BRAF-wildtype CRC, consistent with the one previous study. These findings contribute to an increased understanding of the complex role of body size in CRC.

Adverse effects of being underweight on young female breast cancer patients with lymph node metastases

Background: This study aimed to examine the effect of underweight in breast cancer.

Methods: We performed a retrospective analysis of 3891 female patients diagnosed with primary breast cancer (I-IV stages). Body mass index (BMI) defined by World Health Organization criteria as follow: Underweight (UW; BMI<18.5 kg/m²), normal weight (NW; BMI =18.5-24.9 kg/m²) and overweight or obese (OW; BMI≥25 kg/m²). We performed to evaluate the association between low BMI and clinical outcome in different age (18-40 years and over 40 years) breast cancer.

Results: In our study, about 7% patients suffer from being underweight and 25% patients suffer from being overweight. Underweight is more prominent in young age group. Although no relationship was found between the recurrence rate and being underweight (HR 1.467(95 % CI 0.940-2.291), P=0.092 for disease-free survival), multivariate regression analysis confirmed that low BMI was an independent overall survival (OS) prognostic factor in young patients (HR 1.610(95 % CI 1.028-2.523), P=0.037 for OS). Further analysis showed the prognostic significance of underweight only seen in young patients with axillary lymph node metastasis or III-IV stage patients.

Conclusions: Our results demonstrate the prognostic importance of low BMI in young breast cancer patients (under 40 years old) with lymph node metastases. The role of low BMI in breast cancer might depend on patients' age and clinical stage.

Systemic Actions of Breast Cancer Facilitate Functional Limitations

Breast cancer is a disease of a specific organ, but its effects are felt throughout the body. The systemic effects of breast cancer can lead to functional limitations in patients who suffer from muscle weakness, fatigue, pain, fibromyalgia, or many other dysfunctions, which hasten cancer-associated death. Mechanistic studies have identified quite a few molecular defects in skeletal muscles that are associated with functional limitations in breast cancer. These include circulating cytokines such as TNF-α, IL-1, IL-6, and TGF-β altering the levels or function of myogenic molecules including PAX7, MyoD, and microRNAs through transcriptional regulators such as NF-κB, STAT3, and SMADs. Molecular defects in breast cancer may also include reduced muscle mitochondrial content and increased extracellular matrix deposition leading to energy imbalance and skeletal muscle fibrosis. This review highlights recent evidence that breast cancer-associated molecular defects mechanistically contribute to functional limitations and further provides insights into therapeutic interventions in managing functional limitations, which in turn may help to improve quality of life in breast cancer patients.

The Body Weight Alteration and Incidence of Neoplasm in Patients With Type 2 Diabetes: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

Whether hypoglycemic treatments with weight-alternating effects influence the incidence of neoplasm in type 2 diasbetes (T2D) remains uncertain. Therefore, we performed a meta-analysis to assess the association between the weight alteration and incidence of neoplasm in patients with T2D.

RESEARCH DESIGN AND METHODS

Systematic searches were conducted for studies published between the inception of 1950s and September 2019. Randomized controlled trials conducted in T2D patients with at least 48-week follow-up, significant weight change difference between treatment arms and reports of neoplasm events were included. Fixed-effects model and meta-regression analysis were accordingly used.

RESULTS

In all, 46 studies were included. Analysis indicated weight reduction was not associated with a decreased incidence of neoplasm (OR = 1.01, 95% CI, 0.96 to 1.07, I² = 17%) and weight elevation was not associated with an increased incidence of neoplasm (OR = 0.91, 95% CI, 0.76 to 1.09, I² = 0%). Meta-regression analysis showed a slower weight reduction rate (β = -5.983, 95% CI, -11.412 to 0.553, P = 0.03) instead of weight change difference (β = -0.030, 95% CI, -0.068 to 0.007, P = 0.115) was significantly associated with reduced risk of neoplasm in patients with T2D. Moreover, a decreased incidence of prostate, bladder, and uterine neoplasm was observed in T2D patients with weight reduction difference while an increased incidence of thyroid neoplasm was found in glucagon-like peptide-1 receptor analog (GLP-1RA) users with weight reduction difference.

CONCLUSIONS

Additional weight change achieved by current hypoglycemic agents or strategies in short and medium periods was not associated with incidence of most neoplasm in patients with T2D. However, a decreased incidence of prostate, bladder, and uterine neoplasm was shown in T2D patients with weight reduction difference while an increased risk of thyroid neoplasm was observed in T2D patients on GLP-1RA treatments with weight reduction difference. A more sustained and persistent weight reduction process may confer reduced risk of neoplasm in patients with T2D.

The effect of home-based low-volume, high-intensity interval training on cardiorespiratory fitness, body composition and cardiometabolic health in women of normal body mass and those with overweight or obesity: protocol for a randomized controlled trial

Background

There is a high prevalence of women in South Africa with overweight and obesity which is associated with an increased risk of cardiometabolic disorders. Perceived barriers such as lack of time and motivation reduce engagement in beneficial activity behaviours for health. High-intensity interval training (HIIT) is a time-efficient and effective way to improve cardiometabolic risk profile regardless of a loss in body mass or change in body composition. This randomized controlled trial aims to determine the effects on cardiorespiratory fitness, body composition and cardiometabolic health and feasibility of a home-based 14-week HIIT program in women with overweight/obesity or normal body mass.

Methods

One hundred and twenty women (18–40 years old) with a body mass index between 20 and 35 kg/m², will be stratified according to their BMI (normal, BMI 20–24.9 kg/m²; or high BMI ≥25 kg/m²) and randomized into a HIIT exercising group (HIIT) or a non-exercising control group (CON). HIIT participants will perform exercises for 11 min/session six times per week for a period of 14 weeks. The 2 × 4 HIIT protocol will require a work phase of own-body weight exercise lasting 2 minutes (85% VO₂peak), repeated four times and separated by a one-minute active rest phase (65% VO₂peak). CON participants will be asked to maintain their normal habitual lifestyle. Outcomes of cardiorespiratory fitness, body composition, echocardiography, central blood pressure, arterial stiffness and biomarkers of cardiometabolic health will be measured before and after the 14-week intervention. Every 4 weeks during the intervention, an objective estimation of compliance to the study protocol will be assessed by measuring participant physical activity over 7 days using an Actigraph GT3X accelerometer.

Discussion

Supervised laboratory-based HIIT interventions are effective in improving cardiometabolic health. More pragmatic exercise protocols may however show to be successful for mitigating barriers to the engagement in physical activity and exercise resulting in positive benefits to health. Investigation into home-based HIIT regimens are important in women, where globally the rising trend of overweight and obesity overshadows that of men. The results from this study may therefore inform future research on effective exercise prescription for women’s health.

Trial registration

Pan African Clinical Trial Registry (www.pactr.org - id no: PACTR201806003434299), 6th June 2018.

The Effects of Reverse Causality and Selective Attrition on the Relationship Between Body Mass Index and Mortality in Postmenopausal Women

Concerns about reverse causality and selection bias complicate the interpretation of studies of body mass index (BMI, calculated as weight (kg)/height (m)2) and mortality in older adults. The objective of this study was to investigate methodological explanations for the apparent attenuation of obesity-related risks in older adults. We used data from 68,132 participants in the Women's Health Initiative (WHI) clinical trial for this analysis. All of the participants were postmenopausal women aged 50-79 years at baseline (1993-1998). To examine reverse causality and selective attrition, we compared rate ratios from inverse probability of treatment- and censoring-weighted Poisson marginal structural models with results from an unweighted adjusted Poisson regression model. The estimated mortality rate ratios and 95% confidence intervals for BMIs of 30.0-34.9, 35.0-39.9 and ≥40.0 were 0.86 (95% confidence interval (CI): 0.77, 0.96), 0.85 (95% CI: 0.72, 0.99), and 0.88 (95% CI: 0.72, 1.07), respectively, in the unweighted model. The corresponding mortality rate ratios were 0.96 (95% CI: 0.86, 1.07), 1.12 (95% CI: 0.97, 1.29), and 1.31 95% CI: (1.08, 1.57), respectively, in the marginal structural model. Results from the inverse probability of treatment- and censoring-weighted marginal structural model were attenuated in low BMI categories and increased in high BMI categories. The results demonstrate the importance of accounting for reverse causality and selective attrition in studies of older adults.