Associations between BMI in youth and site-specific cancer in men-A cohort study with register linkage

OBJECTIVE

This study examined BMI in young men and incident site-specific cancer to estimate population attributable fractions due to BMI based on projected obesity prevalence.

METHODS

A population-based cohort study with measured height and weight at age 18. Cox regression models assessed linear associations for BMI and included age, year, and site of conscription as well as parental level of education as covariates.

RESULTS

Primary analyses were performed in 1,489,115 men, of whom 78,217 subsequently developed cancer during a mean follow-up of 31 years. BMI was linearly associated with risk of developing all 18 site-specific cancers assessed (malignant melanoma; leukemia; myeloma; Hodgkin lymphoma; non-Hodgkin lymphoma; and cancer in the lungs, head and neck, central nervous system, thyroid, esophagus, stomach, pancreas, liver and gallbladder, colon, rectum, kidney, and bladder), in some instances evident at BMI levels usually defined as normal (20-25 kg/m2 ). Higher BMI was associated with lower risk of prostate cancer. The highest hazard ratios and population attributable fractions were seen for some gastrointestinal cancers.

CONCLUSIONS

This study reports linear associations between BMI at age 18 and subsequent site-specific cancers, calling for rapid action to stem the obesity epidemic and to prepare the health care system for steep increases in cancer cases.

Periodontitis is associated with airflow obstruction in the Malmö Offspring Dental Study

AIM

To investigate the association between periodontitis and lung function in the Malmö Offspring Dental Study.

MATERIALS AND METHODS

In all 1001 individuals (49.9% female, mean age: 44.6) from Malmö Offspring Dental Study were included. Periodontitis was assessed by a full-mouth examination protocol including bleeding on probing and classified according to the American Academy of Periodontology/Center for Disease Control definitions. Forced expiratory volume in 1 s (FEV1 ) and forced vital capacity (FVC) were expressed as absolute values and %predicted according to Global Lung Function Initiative reference values. FEV1 , FVC and FEV1 /FVC were analysed in relation to periodontal status using linear regression.

RESULTS

Severe periodontitis was found in 7% of the population. Adjusted regression models showed significant associations between lung function and severe periodontitis with 2.1 unit lower FEV1 /FVC ratio (95% CI: -3.91, -0.23) and odds ratio (adjusted) of 2.56 (95% CI: 1.40, 4.75, p = .003) for airflow obstruction (FEV1 /FVC less than the lower limit of normal) if having severe periodontitis. Lower values of %predicted FEV1 and %predicted FVC, but not FEV1 /FVC, were found in individuals with >25% bleeding on probing.

CONCLUSIONS

Severe periodontitis was associated with lower FEV1 /FVC ratio and airflow obstruction in the present cohort. More large-scale prospective studies and intervention studies are required for a comprehensive evaluation.

Phenylacetylglutamine and trimethylamine N-oxide: Two uremic players, different actions

BACKGROUND

Chronic kidney disease (CKD) patients exhibit a heightened cardiovascular (CV) risk which may be partially explained by increased medial vascular calcification. Although gut-derived uremic toxin trimethylamine N-oxide (TMAO) is associated with calcium-phosphate deposition, studies investigating phenylacetylglutamine's (PAG) pro-calcifying potential are missing.

METHODS

The effect of TMAO and PAG in vascular calcification was investigated using 120 kidney failure patients undergoing living-donor kidney transplantation (LD-KTx), in an observational, cross-sectional manner. Uremic toxin concentrations were related to coronary artery calcification (CAC) score, epigastric artery calcification score, and markers of established non-traditional risk factors that constitute to the 'perfect storm' that drives early vascular aging in this patient population. Vascular smooth muscle cells were incubated with TMAO or PAG to determine their calcifying effects in vitro and analyse associated pathways by which these toxins may promote vascular calcification.

RESULTS

TMAO, but not PAG, was independently associated with CAC score after adjustment for CKD-related risk factors in kidney failure patients. Neither toxin was associated with epigastric artery calcification score; however, PAG was independently, positively associated with 8-hydroxydeoxyguanosine. Similarly, TMAO, but not PAG, promoted calcium-phosphate deposition in vitro, while both uremic solutes induced oxidative stress.

CONCLUSIONS

In conclusion, our translational data confirm TMAO's pro-calcifying effects, but both toxins induced free radical production detrimental to vascular maintenance. Our findings suggest these gut-derived uremic toxins have different actions on the vessel wall and therapeutically targeting TMAO may help reduce CV-related mortality in CKD.

Ultraprocessed foods and chronic kidney disease-double trouble

High energy intake combined with low physical activity generates positive energy balance, which, when maintained, favours obesity, a highly prevalent morbidity linked to development of non-communicable chronic diseases, including chronic kidney disease (CKD). Among many factors contributing to disproportionately high energy intakes, and thereby to the obesity epidemic, the type and degree of food processing play an important role. Ultraprocessed foods (UPFs) are industrialized and quite often high-energy-dense products with added sugar, salt, unhealthy fats and food additives formulated to be palatable or hyperpalatable. UPFs can trigger an addictive eating behaviour and is typically characterized by an increase in energy intake. Furthermore, high consumption of UPFs, a hallmark of a Western diet, results in diets with poor quality. A high UPF intake is associated with higher risk for CKD. In addition, UPF consumption by patients with CKD is likely to predispose and/or to exacerbate uraemic metabolic derangements, such as insulin resistance, metabolic acidosis, hypertension, dysbiosis, hyperkalaemia and hyperphosphatemia. Global sales of UPFs per capita increased in all continents in recent decades. This is an important factor responsible for the nutrition transition, with home-made meals being replaced by ready-to-eat products. In this review we discuss the potential risk of UPFs in activating hedonic eating and their main implications for health, especially for kidney health and metabolic complications of CKD. We also present various aspects of consequences of UPFs on planetary health and discuss future directions for research to bring awareness of the harms of UPFs within the CKD scenario.

Comparisons of Different Carbohydrate Quality Indices for Risk of Type 2 Diabetes in the Malmö Diet and Cancer Study

Carbohydrate quality might be more important than quantity to reduce type 2 diabetes (T2D) risk. Various metrics of carbohydrate quality exist; however, their associations with T2D have only been studied to a limited extent. Consequently, the aim was to investigate the association between four different pre-defined carbohydrate quality indices, with various amounts of fiber (≥1 g) and free sugar (<1 or <2 g) per 10 g of carbohydrates, and T2D risk among 26,622 individuals without diabetes from the Malmö Diet and Cancer cohort. Dietary data were collected through a food diary, diet frequency questionnaire, and interview. After a mean follow-up of 18 years, 4046 cases were identified through registers. After adjusting for potential confounders, no statistically significant associations were found for any of the indices. When excluding individuals with past dietary changes and potential misreporting of energy (36% of the population), lower risk was found for the following intake ratios: 10:1:2 carbohydrate:fiber:free sugar (HR = 0.82; 95% CI = 0.70-0.97), and 10:1&1:2 carbohydrate:fiber and fiber:free sugar, respectively (HR = 0.84; 95% CI = 0.72-0.97). Our findings indicate that adherence to a diet with high amounts of fiber and moderate amounts of free sugar in relation to total carbohydrate intake may be associated with a lower risk of T2D.

The EAT-Lancet diet, genetic susceptibility and risk of atrial fibrillation in a population-based cohort

BACKGROUND

The EAT-Lancet Commission proposed a global reference diet with both human health benefits and environmental sustainability in 2019. However, evidence regarding the association of such a diet with the risk of atrial fibrillation (AF) is lacking. In addition, whether the genetic risk of AF can modify the effect of diet on AF remains unclear. This study aimed to assess the association of the EAT-Lancet diet with the risk of incident AF and examine the interaction between the EAT-Lancet diet and genetic susceptibility of AF.

METHODS

This prospective study included 24,713 Swedish adults who were free of AF, coronary events, and stroke at baseline. Dietary habits were estimated with a modified diet history method, and an EAT-Lancet diet index was constructed to measure the EAT-Lancet reference diet. A weighted genetic risk score was constructed using 134 variants associated with AF. Cox proportional hazards regression models were applied to estimate the hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

During a median follow-up of 22.9 years, 4617 (18.7%) participants were diagnosed with AF. The multivariable HR (95% CI) of AF for the highest versus the lowest group for the EAT-Lancet diet index was 0.84 (0.73, 0.98) (P for trend < 0.01). The HR (95% CI) of AF per one SD increment of the EAT-Lancet diet index for high genetic risk was 0.92 (0.87, 0.98) (P for interaction = 0.15).

CONCLUSIONS

Greater adherence to the EAT-Lancet diet index was significantly associated with a lower risk of incident AF. Such association tended to be stronger in participants with higher genetic risk, though gene-diet interaction was not significant.

Bone mineral density and mortality in end-stage renal disease patients

Osteoporosis characterized by low bone mineral density (BMD) as assessed by dual-energy X-ray absorptiometry (DXA) is common among end-stage renal disease (ESRD) patients and associates with high fracture incidence and high all-cause mortality. This is because chronic kidney disease-mineral bone disorders (CKD-MBDs) promote not only bone disease (osteoporosis and renal dystrophy) but also vascular calcification and cardiovascular disease. The disturbed bone metabolism in ESRD leads to 'loss of cortical bone' with increased cortical porosity and thinning of cortical bone rather than to loss of trabecular bone. Low BMD, especially at cortical-rich bone sites, is closely linked to CKD-MBD, vascular calcification and poor cardiovascular outcomes. These effects appear to be largely mediated by shared mechanistic pathways via the 'bone-vascular axis' through which impaired bone status associates with changes in the vascular wall. Thus, bone is more than just the scaffolding that holds the body together and protects organs from external forces but is-in addition to its physical supportive function-also an active endocrine organ that interacts with the vasculature by paracrine and endocrine factors through pathways including Wnt signalling, osteoprotegerin (OPG)/receptor activator of nuclear factor-κB (RANK)/RANK ligand system and the Galectin-3/receptor of advanced glycation end products axis. The insight that osteogenesis and vascular calcification share many similarities-and the knowledge that vascular calcification is a cell-mediated active rather than a passive mineralization process-suggest that low BMD and vascular calcification ('vascular ossification') to a large extent represent two sides of the same coin. Here, we briefly review changes of BMD in ESRD as observed using different DXA methods (central and whole-body DXA) at different bone sites for BMD measurements, and summarize recent knowledge regarding the relationships between 'low BMD' and 'fracture incidence, vascular calcification and increased mortality' in ESRD patients, as well as potential 'molecular mechanisms' underlying these associations.

A Health-Conscious Food Pattern Is Associated with Prediabetes and Gut Microbiota in the Malmö Offspring Study

BACKGROUND

Diet is a determinant of gut microbiota. Both diet and gut microbiota have been linked to metabolic diseases.

OBJECTIVE

We aimed to examine data-driven food patterns in relation to the prevalence of prediabetes and gut microbiota composition and food pattern-associated bacteria in relation to prediabetes.

METHODS

Food patterns were extracted using principal component analysis in 1726 individuals (aged 18-71 y, 55% women, mean BMI = 25.5 kg/m2) without diabetes from the population-based Malmö Offspring Study. The gut (fecal) microbiota was analyzed by sequencing the 16S ribosomal RNA gene (V1-V3 region). Prediabetes classification was based on fasting glucose ≥6.0 mmol/L and/or glycated hemoglobin ≥42 mmol/L at baseline and/or type 2 diabetes diagnosis during follow-up (0-3.8 y). Logistic regression was used to investigate cross-sectional associations with prediabetes, and the general linear model to examine associations between food patterns and bacterial genera.

RESULTS

Two food patterns, the Health-conscious and the Sugar and High-Fat Dairy patterns, were identified. Adherence to the Health-conscious pattern was associated with a lower prevalence of prediabetes (OR comparing highest quintile with lowest: 0.54; 95% CI: 0.32, 0.92; P-trend = 0.03) and with the abundance of several gut bacterial genera, of which the most robust findings were with a higher abundance of Roseburia and Lachnospira and with a lower abundance of Eubacterium. Roseburia was also associated with a lower prevalence of prediabetes (OR comparing highest quintile with lowest: 0.56; 95% CI: 0.35, 0.92; P-trend = 0.01) and the association between the Health-conscious pattern and prediabetes was attenuated after adjustment for abundance of Roseburia and BMI. Adherence to the Sugar and High-Fat Dairy pattern was associated with a higher prevalence of prediabetes in women (P-trend across food pattern quintiles = 0.03).

CONCLUSIONS

In this Swedish population-based study, a Health-conscious food pattern showed an inverse association with the prevalence of prediabetes. Potential underlying explanations may involve links between healthy diet and BMI, as well as gut microbiota, especially a higher abundance of Roseburia.