Majken K. Jensen

General and Abdominal Adiposity and Risk of Death in Europe

BACKGROUND Previous studies have relied predominantly on the body-mass index (BMI, the weight in kilograms divided by the square of the height in meters) to assess the association of adiposity with the risk of death, but few have examined whether the distribution of body fat contributes to the prediction of death. METHODS We examined the association of BMI, waist circumference, and waist-to-hip ratio with the risk of death among 359,387 participants from nine countries in the European Prospective Investigation into Cancer and Nutrition (EPIC). We used a Cox regression analysis, with age as the time variable, and stratified the models according to study center and age at recruitment, with further adjustment for educational level, smoking status, alcohol consumption, physical activity, and height. RESULTS During a mean follow-up of 9.7 years, 14,723 participants died. The lowest risks of death related to BMI were observed at a BMI of 25.3 for men and 24.3 for women. After adjustment for BMI, waist circumference and waist-to-hip ratio were strongly associated with the risk of death. Relative risks among men and women in the highest quintile of waist circumference were 2.05 (95% confidence interval [CI], 1.80 to 2.33) and 1.78 (95% CI, 1.56 to 2.04), respectively, and in the highest quintile of waist-to-hip ratio, the relative risks were 1.68 (95% CI, 1.53 to 1.84) and 1.51 (95% CI, 1.37 to 1.66), respectively. BMI remained significantly associated with the risk of death in models that included waist circumference or waist-to-hip ratio (P<0.001). CONCLUSIONS These data suggest that both general adiposity and abdominal adiposity are associated with the risk of death and support the use of waist circumference or waist-to-hip ratio in addition to BMI in assessing the risk of death.

Multiple Independent Loci at Chromosome 15q25.1 Affect Smoking Quantity: a Meta-Analysis and Comparison with Lung Cancer and COPD

Recently, genetic association findings for nicotine dependence, smoking behavior, and smoking-related diseases converged to implicate the chromosome 15q25.1 region, which includes the CHRNA5-CHRNA3-CHRNB4 cholinergic nicotinic receptor subunit genes. In particular, association with the nonsynonymous CHRNA5 SNP rs16969968 and correlates has been replicated in several independent studies. Extensive genotyping of this region has suggested additional statistically distinct signals for nicotine dependence, tagged by rs578776 and rs588765. One goal of the Consortium for the Genetic Analysis of Smoking Phenotypes (CGASP) is to elucidate the associations among these markers and dichotomous smoking quantity (heavy versus light smoking), lung cancer, and chronic obstructive pulmonary disease (COPD). We performed a meta-analysis across 34 datasets of European-ancestry subjects, including 38,617 smokers who were assessed for cigarettes-per-day, 7,700 lung cancer cases and 5,914 lung-cancer-free controls (all smokers), and 2,614 COPD cases and 3,568 COPD-free controls (all smokers). We demonstrate statistically independent associations of rs16969968 and rs588765 with smoking (mutually adjusted p-values<10−35 and <10−8 respectively). Because the risk alleles at these loci are negatively correlated, their association with smoking is stronger in the joint model than when each SNP is analyzed alone. Rs578776 also demonstrates association with smoking after adjustment for rs16969968 (p<10−6). In models adjusting for cigarettes-per-day, we confirm the association between rs16969968 and lung cancer (p<10−20) and observe a nominally significant association with COPD (p = 0.01); the other loci are not significantly associated with either lung cancer or COPD after adjusting for rs16969968. This study provides strong evidence that multiple statistically distinct loci in this region affect smoking behavior. This study is also the first report of association between rs588765 (and correlates) and smoking that achieves genome-wide significance; these SNPs have previously been associated with mRNA levels of CHRNA5 in brain and lung tissue.

Fruit and vegetable intake and the risk of stomach and oesophagus adenocarcinoma in the European Prospective Investigation into Cancer and Nutrition (EPIC-EURGAST).

It is considered that fruit and vegetable (F&V) protect against oesophagus and gastric cancer (GC). However, 2 recent meta‐analyses suggest that the strength of association on GC seems to be weaker for vegetables than for fruit and weaker in cohort than in case‐control studies. No evidence exists from cohort studies about adenocarcinoma of oesophagus (ACO). In 521,457 men and women participating in the EPIC cohort in 10 European countries, information of diet and lifestyle was collected at baseline. After an average of 6.5 years of follow‐up, a total of 330 GC and 65 ACO, confirmed and classified by a panel of pathologists, was used for the analysis. We examined the relation between F&V intake and GC and ACO. A calibration study in a sub‐sample was used to control diet measurement errors. In a sub‐sample of cases and a random sample of controls, antibodies against Helicobacter pylori (Hp) were measured and interactions with F&V were examined in a nested case‐control study. We observed no association with total vegetable intake or specific groups of vegetables and GC risk, except for the intestinal type, where a negative association is possible regarding total vegetable (calibrated HR 0.66; 95% CI 0.35–1.22 per 100 g increase) and onion and garlic intake (calibrated HR 0.70; 95% CI 0.38–1.29 per 10 g increase). No evidence of association between fresh fruit intake and GC risk was observed. We found a negative but non significant association between citrus fruit intake and the cardia site (calibrated HR 0.77; 95% CI 0.47–1.22 per 100 g increase) while no association was observed with the non‐cardia site. Regarding ACO, we found a non significant negative association for vegetable intake and for citrus intake (calibrated HRs 0.72; 95% CI 0.32–1.64 and 0.77; 95% CI 0.46–1.28 per 100 and 50 g increase, respectively). It seems that Hp infection does not modify the effect of F&V intake. Our study supports a possible protective role of vegetable intake in the intestinal type of GC and the ACO. Citrus fruit consumption may have a role in the protection against cardia GC and ACO.

Drinking Frequency, Mediating Biomarkers, and Risk of Myocardial Infarction in Women and Men

Background—The associations of drinking frequency and quantity with risk of myocardial infarction have not been studied among women, and the degree to which specific risk factors mediate the inverse association of drinking frequency with risk of myocardial infarction is uncertain. Methods and Results—We conducted nested case-control studies of 32 826 women enrolled in the Nurses Health Study followed up from 1990 to 1998 and 18 225 men enrolled in the Health Professionals Follow-Up Study followed up from 1994 to 2000. A total of 249 women and 266 men with incident myocardial infarction were matched on age, smoking, and date of entry to 498 female and 532 male control participants. We determined the risk of myocardial infarction related to frequency and quantity of alcohol intake and the change in risk before and after adjustment for putative cardiovascular risk factors. Among both women and men, drinking frequency tended to be associated with lower risk of myocardial infarction, with the lowest risks among those who drank 3 to 7 days per week. Further adjustment for levels of high-density lipoprotein cholesterol, hemoglobin A1c, and fibrinogen attenuated 75% of the association of frequent drinking with risk among women and fully attenuated the association among men. Conclusions—Alcohol intake at least 3 to 4 days per week is associated with a lower risk of myocardial infarction among women and men, an association apparently attributable to the relationship of alcohol with HDL cholesterol, fibrinogen, and hemoglobin A1c. Because the effects of alcohol on HDL cholesterol, fibrinogen, and insulin sensitivity have been confirmed in randomized trials, our findings support the hypothesis that the inverse relation of alcohol use and myocardial infarction is causal.

Lifetime and baseline alcohol intake and risk of colon and rectal cancers in the European prospective investigation into cancer and nutrition (EPIC)

Alcohol consumption may be associated with risk of colorectal cancer (CRC), but the epidemiological evidence for an association with specific anatomical subsites, types of alcoholic beverages and current vs. lifetime alcohol intake is inconsistent. Within the European Prospective Investigation into Cancer and Nutrition (EPIC), 478,732 study subjects free of cancer at enrolment between 1992 and 2000 were followed up for an average of 6.2 years, during which 1,833 CRC cases were observed. Detailed information on consumption of alcoholic beverages at baseline (all cases) and during lifetime (1,447 CRC cases, 69% of the cohort) was collected from questionnaires. Cox proportional hazard models were used to examine the alcohol‐CRC association. After adjustment for potential confounding factors, lifetime alcohol intake was significantly positively associated to CRC risk (hazard ratio, HR = 1.08, 95%CI = 1.04–1.12 for 15 g/day increase), with higher cancer risks observed in the rectum (HR = 1.12, 95%CI = 1.06–1.18) than distal colon (HR = 1.08, 95%CI = 1.01–1.16), and proximal colon (HR = 1.02, 95%CI = 0.92–1.12). Similar results were observed for baseline alcohol intake. When assessed by alcoholic beverages at baseline, the CRC risk for beer (HR = 1.38, 95%CI = 1.08–1.77 for 20–39.9 vs. 0.1–2.9 g/day) was higher than wine (HR = 1.21, 95%CI = 1.02–1.44), although the two risk estimates were not significantly different from each other. Higher HRs for baseline alcohol were observed for low levels of folate intake (1.13, 95%CI = 1.06–1.20 for 15 g/day increase) compared to high folate intake (1.03, 95%CI = 0.98–1.09). In this large European cohort, both lifetime and baseline alcohol consumption increase colon and rectum cancer risk, with more apparent risk increases for alcohol intakes greater than 30 g/day.

Prospective study of alcohol drinking patterns and coronary heart disease in women and men

Abstract Objective To determine the association between alcohol drinking patterns and risk of coronary heart disease in women and men. Design Population based cohort study. Setting Denmark, 1993-2002. Participants 28 448 women and 25 052 men aged 50-65 years, who were free of cardiovascular disease at entry to the study. Main outcome measures Incidence of coronary heart disease occurring during a median follow-up period of 5.7 years. Results 749 and 1283 coronary heart disease events occurred among women and men. Women who drank alcohol on at least one day a week had a lower risk of coronary heart disease than women who drank alcohol on less than one day a week. Little difference was found, however, between drinking frequency: one day a week (hazard ratio 0.64, 95% confidence interval 0.51 to 0.81), 2-4 days a week (0.63, 0.52 to 0.77), five or six days a week (0.79, 0.61 to 1.03), and seven days a week (0.65, 0.51 to 0.84). For men an inverse association was found between drinking frequency and risk of coronary heart disease across the entire range of drinking frequencies. The lowest risk was observed among men who drank daily (0.59, 0.48 to 0.71) compared with men who drank alcohol on less than one day a week. Conclusions Among women alcohol intake may be the primary determinant of the inverse association between drinking alcohol and risk of coronary heart disease whereas among men, drinking frequency, not alcohol intake, seems more important.

Loss-of-function variants in endothelial lipase are a cause of elevated HDL cholesterol in humans

Elevated plasma concentrations of HDL cholesterol (HDL-C) are associated with protection from atherosclerotic cardiovascular disease. Animal models indicate that decreased expression of endothelial lipase (LIPG) is inversely associated with HDL-C levels, and genome-wide association studies have identified LIPG variants as being associated with HDL-C levels in humans. We hypothesized that loss-of-function mutations in LIPG may result in elevated HDL-C and therefore performed deep resequencing of LIPG exons in cases with elevated HDL-C levels and controls with decreased HDL-C levels. We identified a significant excess of nonsynonymous LIPG variants unique to cases with elevated HDL-C. In vitro lipase activity assays demonstrated that these variants significantly decreased endothelial lipase activity. In addition, a meta-analysis across 5 cohorts demonstrated that the low-frequency Asn396Ser variant is significantly associated with increased HDL-C, while the common Thr111Ile variant is not. Functional analysis confirmed that the Asn396Ser variant has significantly decreased lipase activity both in vitro and in vivo, while the Thr111Ile variant has normal lipase activity. Our results establish that loss-of-function mutations in LIPG lead to increased HDL-C levels and support the idea that inhibition of endothelial lipase may be an effective mechanism to raise HDL-C.

Genome-Wide Meta-Analysis Identifies Regions on 7p21 (AHR) and 15q24 (CYP1A2) As Determinants of Habitual Caffeine Consumption

We report the first genome-wide association study of habitual caffeine intake. We included 47,341 individuals of European descent based on five population-based studies within the United States. In a meta-analysis adjusted for age, sex, smoking, and eigenvectors of population variation, two loci achieved genome-wide significance: 7p21 (P = 2.4×10−19), near AHR, and 15q24 (P = 5.2×10−14), between CYP1A1 and CYP1A2. Both the AHR and CYP1A2 genes are biologically plausible candidates as CYP1A2 metabolizes caffeine and AHR regulates CYP1A2.

Adherence to a Mediterranean diet and risk of gastric adenocarcinoma within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study

BACKGROUND The Mediterranean dietary pattern is believed to protect against cancer, although evidence from cohort studies that have examined particular cancer sites is limited. OBJECTIVE We aimed to explore the association between adherence to a relative Mediterranean diet (rMED) and incident gastric adenocarcinoma (GC) within the European Prospective Investigation into Cancer and Nutrition study. DESIGN The study included 485,044 subjects (144,577 men) aged 35-70 y from 10 European countries. At recruitment, dietary and lifestyle information was collected. An 18-unit rMED score, incorporating 9 key components of the Mediterranean diet, was used to estimate rMED adherence. The association between rMED and GC with respect to anatomic location (cardia and noncardia) and histologic types (diffuse and intestinal) was investigated. A calibration study in a subsample was used to control for dietary measurement error. RESULTS After a mean follow-up of 8.9 y, 449 validated incident GC cases were identified and used in the analysis. After stratification by center and age and adjustment for recognized cancer risk factors, high compared with low rMED adherence was associated with a significant reduction in GC risk (hazard ratio: 0.67; 95% CI: 0.47, 0.94). A 1-unit increase in the rMED score was associated with a decreased risk of GC of 5% (95% CI: 0.91, 0.99). There was no evidence of heterogeneity between different anatomic locations or histologic types. The calibrated results showed similar trends (overall hazard ratio for GC: 0.93; 95% CI: 0.89, 0.99). CONCLUSION Greater adherence to an rMED is associated with a significant reduction in the risk of incident GC.

Obesity, Behavioral Lifestyle Factors, and Risk of Acute Coronary Events

Background— Whether physical activity reduces the impact of obesity on the risk of acute coronary events is much debated. However, little is known about the role of other potentially modifiable lifestyle factors in combination with obesity. Methods and Results— We followed up 54 783 women and men from the prospective Danish Diet, Cancer and Health study who were 50 to 64 years at baseline (1993 to 1997) and free of coronary artery disease and cancer. During a median of 7.7 years, 1127 incident cases of acute coronary syndrome (ACS) occurred. After multivariable adjustments, each unit of body mass index was associated with a 5% and 7% higher risk of ACS among women and men, respectively (both P<0.0001 for trend). Overweight (body mass index, 25 to 29.9 kg/m2) and obesity (body mass index ≥30 kg/m2) were associated with a higher risk of ACS among the physically active and inactive, in nonsmokers and smokers, and among those who adhered more or less to a heart-healthy dietary pattern. Obese individuals who were active 1 to 3.5 h/wk had a lower risk than sedentary, obese individuals. In addition, obese nonsmokers had a lower risk than obese smokers. Adherence to a healthy diet was associated with a lower risk of ACS; however, the relative risk was not different among obese individuals with the most healthy diet versus obese individuals with a less healthy diet. Conclusions— Obesity confers an elevated risk of ACS in both healthy and less healthy subgroups of lifestyle behaviors. Adherence to healthy lifestyle behaviors was associated with a lower risk even among obese individuals.