Life expectancy associated with different ages at diagnosis of type 2 diabetes in high-income countries: 23 million person-years of observation

BACKGROUND

The prevalence of type 2 diabetes is increasing rapidly, particularly among younger age groups. Estimates suggest that people with diabetes die, on average, 6 years earlier than people without diabetes. We aimed to provide reliable estimates of the associations between age at diagnosis of diabetes and all-cause mortality, cause-specific mortality, and reductions in life expectancy.

METHODS

For this observational study, we conducted a combined analysis of individual-participant data from 19 high-income countries using two large-scale data sources: the Emerging Risk Factors Collaboration (96 cohorts, median baseline years 1961-2007, median latest follow-up years 1980-2013) and the UK Biobank (median baseline year 2006, median latest follow-up year 2020). We calculated age-adjusted and sex-adjusted hazard ratios (HRs) for all-cause mortality according to age at diagnosis of diabetes using data from 1 515 718 participants, in whom deaths were recorded during 23·1 million person-years of follow-up. We estimated cumulative survival by applying age-specific HRs to age-specific death rates from 2015 for the USA and the EU.

FINDINGS

For participants with diabetes, we observed a linear dose-response association between earlier age at diagnosis and higher risk of all-cause mortality compared with participants without diabetes. HRs were 2·69 (95% CI 2·43-2·97) when diagnosed at 30-39 years, 2·26 (2·08-2·45) at 40-49 years, 1·84 (1·72-1·97) at 50-59 years, 1·57 (1·47-1·67) at 60-69 years, and 1·39 (1·29-1·51) at 70 years and older. HRs per decade of earlier diagnosis were similar for men and women. Using death rates from the USA, a 50-year-old individual with diabetes died on average 14 years earlier when diagnosed aged 30 years, 10 years earlier when diagnosed aged 40 years, or 6 years earlier when diagnosed aged 50 years than an individual without diabetes. Using EU death rates, the corresponding estimates were 13, 9, or 5 years earlier.

INTERPRETATION

Every decade of earlier diagnosis of diabetes was associated with about 3-4 years of lower life expectancy, highlighting the need to develop and implement interventions that prevent or delay the onset of diabetes and to intensify the treatment of risk factors among young adults diagnosed with diabetes.

FUNDING

British Heart Foundation, Medical Research Council, National Institute for Health and Care Research, and Health Data Research UK.

The relative importance of particle count, type, and size of ApoB-containing lipoproteins in risk of myocardial infarction

Background

An accumulating body of evidence suggests that the number of apolipoprotein B-containing particles (ApoB-P) is more predictive of cardiovascular risk than their lipid content. However, it is unclear if this association is consistent across different lipoprotein types and sizes.

Purpose

We aimed to evaluate if particle type and size are associated with incident myocardial infarction (MI) beyond ApoB-P count. Moreover, we aimed to determine if the risk associated with lipoprotein(a) is additive to that of ApoB-P.

Methods

This prospective cohort study included 96,126 participants without prior history of stroke, coronary or peripheral artery disease or use of lipid-lowering medication from the UK Biobank. Count and size of VLDL, IDL, LDL, and HDL, as well as ApoB level and total ApoB-P count were measured in non-fasting plasma samples by nuclear magnetic resonance platform. Lipoprotein(a) was measured by immunoturbidimetric assay. We explored associations between these lipoprotein markers and incident MI using Cox proportional hazard models adjusted sequentially for clinical covariates, HDL count and size, and ApoB-P.

Results

Over a median follow-up of 12.1 years, 1702 participants had incident MI. In unadjusted models, 1-SD increases in ApoB-P count, ratio of VLDL to (LDL+IDL) particle counts, VLDL size and lipoprotein(a) were associated with a higher risk of MI, while LDL size was associated with a lower risk of MI (Table 1). When adjusting for clinical covariates and lipid parameters, only ApoB-P and lipoprotein(a) remained significantly associated with a higher risk of MI (HR: 1.40 [1.32; 1.48] and 1.20 [1.14; 1.27], respectively). Adjusted restricted cubic splines confirmed findings from linear trend Cox models (Figure 1). ApoB-P count was highly correlated with ApoB level (r=0.99), and replication of analyses replacing one for another revealed no change in results.

Conclusion

The risk of MI is independently associated with the total particle count of all ApoB-P, and not the size or type of these lipoproteins. ApoB level can be used as a very accurate surrogate of ApoB-P count in the clinical setting. Lipoprotein(a) is associated with MI risk independently of total particle count, and therefore, the combination of ApoB and lipoprotein(a) may provide the optimal clinical evaluation of lipid-mediated MI risk.

Funding Acknowledgement

Type of funding sources: None.

Body shape trajectories and the incidence of hypertension in a Mediterranean cohort: The sun study

AIMS

Our aim was to assess the association between trajectories of body-shape across the first 40 years of life and subsequent development of hypertension in a Mediterranean cohort.

METHODS AND RESULTS

We used a group-based modeling approach to assess body shape trajectories from age 5 to 40 years, among 7514 participants included in the SUN study (1999-2016), and assessed the subsequent incidence of hypertension. To create the trajectories, we used a censored normal model as a polynomial function of age. Cox models were used to estimates hazard ratios (HR) for hypertension according to body shape trajectories. Identified trajectories were "childhood lean -mid-life increase", "childhood medium-mid-life stable", " childhood heavy -mid-life decrease", and "childhood heavy -mid-life increase" for women; and "childhood lean-mid-life increase", "childhood medium-mid-life stable", "childhood medium -mid-life increase" and "childhood heavy-mid-life stable" for men. After a follow-up of 63,068 person-years, 865 incident cases of hypertension were found. Among women, compared to those in the "childhood medium-mid-life stable" trajectory, those, in the "childhood heavy -mid-life increase" trajectory showed higher risk to develop hypertension [HR = 1.72 (1.17-2.53)]. In men, compared with those in the "childhood medium-mid-life stable" trajectory, those in the "childhood lean and childhood medium -mid-life increase" and the "childhood heavy- mid-life stable" trajectories showed higher subsequent incidence of hypertension [HR = 1.43 (1.11-1.85), HR = 1.52 (1.17-1.97) and HR = 1.56 (1.14-2.14), respectively] after adjusting for potential confounders (including age, lifestyles, dietary intake, personality traits, physical activity and sedentary behaviors).

CONCLUSIONS

Our results suggest that mid-life increases in body shape or maintaining a heavy body shape during early and middle life in men and childhood heavy-mid-life increase in women is associated with a higher subsequent risk of developing hypertension in this Mediterranean population.

Olive oil and prevention of chronic diseases: Summary of an International conference

Olive oil is the foremost source of fat in the Mediterranean area and, among other features, sets the Mediterranean diet apart from other dietary regimens. In January 2018, the International Olive Council convened several worldwide experts at the Robert Mondavi Institute (Davis, CA), to discuss and summarize the available data on the effects of olive oil consumption on human health. In this paper, we critically provide a synthesis of the main reported findings, which underscore how and why consuming this oil as part of a balanced diet and healthful lifestyle improves prognosis and extends life- and health-spans.

Associations between benign cutaneous nevi and risk of Type 2 diabetes mellitus in men and women: results from two prospective cohort studies

AIM

To examine the association of cutaneous nevi with Type 2 diabetes risk.

METHODS

We prospectivly examined the associations between nevus count and risk of Type 2 diabetes among 26 240 men (1988-2010) from the Health Professionals Follow-up Study and 67 050 women (1986-2010) from the Nurses' Health Study. Information on the numbers of cutaneous nevi on arms at baseline and incident cases of Type 2 diabetes was collected using validated questionnaires.

RESULTS

During 1 879 287 person-years of follow-up, we documented 9040 incident cases of Type 2 diabetes. After adjustment for age, BMI and other diabetes risk factors, greater number of nevi was associated with higher risk of Type 2 diabetes. Multivariable-adjusted hazard ratios for <1, 1-5, 6-14 and ≥15 nevi were 1.00 (reference), 1.02 (95% CI 0.93, 1.13), 1.08 (95% CI 0.88, 1.34) and 1.57 (95% CI 1.15, 2.15), respectively, for men (P for linear trend = 0.01), and 1.00 (reference), 1.07 (95% CI 1.02, 1.13), 0.98 (95% CI 0.87, 1.10), and 1.25 (1.01, 1.54), respectively, for women (P for linear trend = 0.05). This positive association remained consistent across subgroups stratified by age, BMI, multivitamin use, smoking status, alcohol, physical activity, history of hypercholesterolaemia, family history of diabetes, history of hypertension and menopausal status (in women).

CONCLUSIONS

Cutaneous nevus count may represent a novel marker for development of Type 2 diabetes, suggesting a possible unique melanocytic nevus-related mechanism in the pathogenesis of Type 2 diabetes. Further studies are warranted to confirm the findings and to investigate the underlying mechanisms.

Thyroid hormones and changes in body weight and metabolic parameters in response to weight loss diets: the POUNDS LOST trial

BACKGROUND

The role of thyroid hormones in diet-induced weight loss and subsequent weight regain is largely unknown.

OBJECTIVES

To examine the associations between thyroid hormones and changes in body weight and resting metabolic rate (RMR) in a diet-induced weight loss setting.

SUBJECTS/METHODS

Data analysis was conducted among 569 overweight and obese participants aged 30-70 years with normal thyroid function participating in the 2-year Prevention of Obesity Using Novel Dietary Strategies (POUNDS) LOST randomized clinical trial. Changes in body weight and RMR were assessed during the 2-year intervention. Thyroid hormones (free triiodothyronine (T3), free thyroxine (T4), total T3, total T4 and thyroid-stimulating hormone (TSH)), anthropometric measurements and biochemical parameters were assessed at baseline, 6 months and 24 months.

RESULTS

Participants lost an average of 6.6 kg of body weight during the first 6 months and subsequently regained an average of 2.7 kg of body weight over the remaining period from 6 to 24 months. Baseline free T3 and total T3 were positively associated, whereas free T4 was inversely associated, with baseline body weight, body mass index and RMR. Total T4 and TSH were not associated with these parameters. Higher baseline free T3 and free T4 levels were significantly associated with a greater weight loss during the first 6 months (P<0.05) after multivariate adjustments including dietary intervention groups and baseline body weight. Comparing extreme tertiles, the multivariate-adjusted weight loss±s.e. was -3.87±0.9 vs -5.39±0.9 kg for free T3 (P_trend=0.02) and -4.09±0.9 vs -5.88±0.9 kg for free T4 (P_trend=0.004). The thyroid hormones did not predict weight regain in 6-24 months. A similar pattern of associations was also observed between baseline thyroid hormones and changes in RMR. In addition, changes in free T3 and total T3 levels were positively associated with changes in body weight, RMR, body fat mass, blood pressure, glucose, insulin, triglycerides and leptin at 6 months and 24 months (all P<0.05).

CONCLUSIONS

In this diet-induced weight loss setting, higher baseline free T3 and free T4 predicted more weight loss, but not weight regain among overweight and obese adults with normal thyroid function. These findings reveal a novel role of thyroid hormones in body weight regulation and may help identify individuals more responsive to weight loss diets.

Healthful dietary patterns and long-term weight change among women with a history of gestational diabetes mellitus

BACKGROUND/OBJECTIVE

Diet represents a key strategy for the prevention of obesity and type 2 diabetes among women with a history of gestational diabetes mellitus (GDM), although effective dietary patterns to prevent weight gain in the long term are largely unknown. We sought to evaluate whether improvement in overall diet quality is associated with less long-term weight gain among high-risk women with prior GDM.

SUBJECTS/METHODS

Women with a history of GDM (N=3397) were followed from 1991 to 2011, or until diagnosis of type 2 diabetes or other chronic disease. Usual diet was assessed via food frequency questionnaire every 4 years from which we calculated the Alternative Healthy Eating Index (aHEI-2010), Alternate Mediterranean Diet (AMED) and Dietary Approaches to Stop Hypertension (DASH) dietary pattern scores. Weight, lifestyle and health-related outcomes were self-reported every 2 years. We estimated the change in dietary score with change in body weight using linear regression models adjusting for age, baseline body mass index (BMI), baseline and simultaneous change in physical activity and smoking status and other risk factors.

RESULTS

Women were followed up to 20 years, gaining an average 1.9 kg (s.d.=7.0) per 4-year period. Women in the highest quintile (Q5) of diet change (most improvement in quality) gained significantly less weight per 4-year period than the lowest quintile (Q1; decrease in quality), independent of other risk factors (4-year weight change, aHEI-2010: Q5=1.30 kg vs Q1=3.27 kg; AMED: Q5=0.94 kg vs Q1=2.56 kg, DASH: Q5=0.64 kg vs Q1=2.75 kg). Significant effect modification by BMI (p-interactions <0.001) indicated a greater magnitude of weight change among women with a higher baseline BMI for all three patterns.

CONCLUSIONS

Increased diet quality was associated with less weight gain, independent of other lifestyle factors. Post-partum recommendations on diet quality may provide one strategy to prevent long-term weight gain in this high-risk group.

Is the adiposity-associated FTO gene variant related to all-cause mortality independent of adiposity? Meta-analysis of data from 169,551 Caucasian adults

Previously, a single nucleotide polymorphism (SNP), rs9939609, in the FTO gene showed a much stronger association with all-cause mortality than expected from its association with body mass index (BMI), body fat mass index (FMI) and waist circumference (WC). This finding implies that the SNP has strong pleiotropic effects on adiposity and adiposity-independent pathological pathways that leads to increased mortality. To investigate this further, we conducted a meta-analysis of similar data from 34 longitudinal studies including 169,551 adult Caucasians among whom 27,100 died during follow-up. Linear regression showed that the minor allele of the FTO SNP was associated with greater BMI (n = 169,551; 0.32 kg m(-2) ; 95% CI 0.28-0.32, P < 1 × 10(-32) ), WC (n = 152,631; 0.76 cm; 0.68-0.84, P < 1 × 10(-32) ) and FMI (n = 48,192; 0.17 kg m(-2) ; 0.13-0.22, P = 1.0 × 10(-13) ). Cox proportional hazard regression analyses for mortality showed that the hazards ratio (HR) for the minor allele of the FTO SNPs was 1.02 (1.00-1.04, P = 0.097), but the apparent excess risk was eliminated after adjustment for BMI and WC (HR: 1.00; 0.98-1.03, P = 0.662) and for FMI (HR: 1.00; 0.96-1.04, P = 0.932). In conclusion, this study does not support that the FTO SNP is associated with all-cause mortality independently of the adiposity phenotypes.

Urinary concentrations of bisphenol A and phthalate metabolites and weight change: a prospective investigation in US women

OBJECTIVE

Both bisphenol A (BPA) and phthalates are known endocrine-disrupting chemicals for which there is widespread general population exposure. Human exposure occurs through dietary and non-dietary routes. Although animal studies have suggested a potential role of these chemicals in obesity, evidence from human studies is sparse and inconsistent, and prospective evidence is lacking. This study evaluated urinary concentrations of BPA and major phthalate metabolites in relation to prospective weight change.

METHODS

The study population was from the controls in a prospective case-control study of type 2 diabetes in the Nurses' Health Study (NHS) and NHSII. A total of 977 participants provided first-morning-void urine samples in 1996-2002. Urinary concentrations of BPA and nine phthalate metabolites were measured using liquid chromatography-mass spectrometry. Body weights were self-reported at baseline and updated biennially thereafter for 10 years.

RESULTS

On average, the women gained 2.09 kg (95% confidence interval (CI), -2.27 to 6.80 kg) during the 10-year follow-up. In multivariate analysis with adjustment of lifestyle and dietary factors, in comparison with women in the lowest quartile of BPA concentration, those in the highest quartile had 0.23 kg per year (95% CI, 0.07-0.38 kg per year) greater weight gain during the 10-year follow-up (P-trend=0.02). Several phthalate metabolites, including phthalic acid, MBzP and monobutyl phthalate, were also associated with faster prospective weight gain in a dose-response fashion (P-trend<0.01), whereas other phthalates metabolites, including MEP and monoethylhexyl phthalate, were not monotonically associated with body weight change.

CONCLUSIONS

These data suggest urinary concentrations of BPA and certain individual phthalate metabolites that were associated with modestly greater weight gain in a dose-response fashion. These data are consistent with a potential role of BPA and phthalates in obesity, although more prospective data are needed to corroborate these observations.

Plasma 25-hydroxyvitamin D and risk of metabolic syndrome: an ancillary analysis in the Diabetes Prevention Program

BACKGROUND/OBJECTIVES

Low blood levels of 25-hydroxyvitamin D (25OHD) have been associated with cardiometabolic disease but results are inconsistent. The objective of the study was to investigate the association of 25OHD with metabolic syndrome in a population at increased risk for diabetes.

SUBJECTS/METHODS

Using baseline data from the placebo and lifestyle intervention arms of the Diabetes Prevention Program (N=2000), multivariable logistic regression models were used to estimate the odds of prevalent metabolic syndrome and each of its individual components across 25OHD tertiles. Multivariable linear regression was used to estimate the adjusted mean difference of insulin secretion and sensitivity across the same 25OHD tertiles. In participants free of metabolic syndrome at baseline (N=546), incident metabolic syndrome in the first 2 years of follow-up was assessed using discrete-time proportional hazards regression to test its association with 25OHD concentration.

RESULTS

After multivariate adjustment, participants in the highest tertile of 25OHD had lower odds of prevalent metabolic syndrome (odds ratio=0.62; 95% confidence interval (CI)=0.45-0.84), smaller waist circumference, higher high-density lipoprotein and lower fasting plasma glucose compared with participants in the lowest tertile of 25OHD. Higher plasma 25OHD concentration was associated with greater insulin sensitivity and lower insulin secretion. After multivariate adjustment, there was a nonsignificant lower risk of metabolic syndrome in the highest tertile of 25OHD (hazard ratio=0.79; 95% CI=0.48-1.32) compared with the lowest tertile.

CONCLUSIONS

In a population at increased risk for diabetes, higher plasma 25OHD concentration was inversely associated with prevalent metabolic syndrome and nonsignificantly with incident metabolic syndrome.

Nut consumption and risk of pancreatic cancer in women

Background:

Increasing nut intake has been associated with reduced risk of diabetes mellitus, which is a risk factor for pancreatic cancer.

Methods:

We prospectively followed 75 680 women in the Nurses' Health Study, and examined the association between nut consumption and pancreatic cancer risk. Participants with a previous history of cancer were excluded. Nut consumption was assessed at baseline and updated every 2 to 4 years. Relative risks (RRs) and 95% confidence intervals (95% CIs) were estimated using Cox proportional hazards models.

Results:

We documented 466 incident cases of pancreatic cancer. After adjusting for age, height, smoking, physical activity, and total energy intake, women who consumed a 28-g (1 oz) serving size of nuts ⩾2 times per week experienced a significantly lower risk of pancreatic cancer (RR, 0.65; 95% CI, 0.47–0.92; P for trend=0.007) when compared with those who largely abstained from nuts. The results did not appreciably change after further adjustment for body mass index (BMI) and history of diabetes mellitus (RR, 0.68; 95% CI, 0.48–0.95; P for trend=0.01). The inverse association persisted within strata defined by BMI, physical activity, smoking, and intakes of red meat, fruits, and vegetables.

Conclusion:

Frequent nut consumption is inversely associated with risk of pancreatic cancer in this large prospective cohort of women, independent of other potential risk factors for pancreatic cancer.

Resolved: there is sufficient scientific evidence that decreasing sugar-sweetened beverage consumption will reduce the prevalence of obesity and obesity-related diseases

Sugar-sweetened beverages (SSBs) are the single largest source of added sugar and the top source of energy intake in the U.S. diet. In this review, we evaluate whether there is sufficient scientific evidence that decreasing SSB consumption will reduce the prevalence of obesity and its related diseases. Because prospective cohort studies address dietary determinants of long-term weight gain and chronic diseases, whereas randomized clinical trials (RCTs) typically evaluate short-term effects of specific interventions on weight change, both types of evidence are critical in evaluating causality. Findings from well-powered prospective cohorts have consistently shown a significant association, established temporality and demonstrated a direct dose-response relationship between SSB consumption and long-term weight gain and risk of type 2 diabetes (T2D). A recently published meta-analysis of RCTs commissioned by the World Health Organization found that decreased intake of added sugars significantly reduced body weight (0.80 kg, 95% confidence interval [CI] 0.39-1.21; P < 0.001), whereas increased sugar intake led to a comparable weight increase (0.75 kg, 0.30-1.19; P = 0.001). A parallel meta-analysis of cohort studies also found that higher intake of SSBs among children was associated with 55% (95% CI 32-82%) higher risk of being overweight or obese compared with those with lower intake. Another meta-analysis of eight prospective cohort studies found that one to two servings per day of SSB intake was associated with a 26% (95% CI 12-41%) greater risk of developing T2D compared with occasional intake (less than one serving per month). Recently, two large RCTs with a high degree of compliance provided convincing data that reducing consumption of SSBs significantly decreases weight gain and adiposity in children and adolescents. Taken together, the evidence that decreasing SSBs will decrease the risk of obesity and related diseases such as T2D is compelling. Several additional issues warrant further discussion. First, prevention of long-term weight gain through dietary changes such as limiting consumption of SSBs is more important than short-term weight loss in reducing the prevalence of obesity in the population. This is due to the fact that once an individual becomes obese, it is difficult to lose weight and keep it off. Second, we should consider the totality of evidence rather than selective pieces of evidence (e.g. from short-term RCTs only). Finally, while recognizing that the evidence of harm on health against SSBs is strong, we should avoid the trap of waiting for absolute proof before allowing public health action to be taken.

Changes in water and beverage intake and long-term weight changes: results from three prospective cohort studies

OBJECTIVE

To examine the long-term relationship between changes in water and beverage intake and weight change.

SUBJECTS

Prospective cohort studies of 50013 women aged 40-64 years in the Nurses' Health Study (NHS, 1986-2006), 52987 women aged 27-44 years in the NHS II (1991-2007) and 21988 men aged 40-64 years in the Health Professionals Follow-up Study (1986-2006) without obesity and chronic diseases at baseline.

MEASURES

We assessed the association of weight change within each 4-year interval, with changes in beverage intakes and other lifestyle behaviors during the same period. Multivariate linear regression with robust variance and accounting for within-person repeated measures were used to evaluate the association. Results across the three cohorts were pooled by an inverse-variance-weighted meta-analysis.

RESULTS

Participants gained an average of 1.45 kg (5th to 95th percentile: -1.87 to 5.46) within each 4-year period. After controlling for age, baseline body mass index and changes in other lifestyle behaviors (diet, smoking habits, exercise, alcohol, sleep duration, TV watching), each 1 cup per day increment of water intake was inversely associated with weight gain within each 4-year period (-0.13 kg; 95% confidence interval (CI): -0.17 to -0.08). The associations for other beverages were: sugar-sweetened beverages (SSBs) (0.36 kg; 95% CI: 0.24-0.48), fruit juice (0.22 kg; 95% CI: 0.15-0.28), coffee (-0.14 kg; 95% CI: -0.19 to -0.09), tea (-0.03 kg; 95% CI: -0.05 to -0.01), diet beverages (-0.10 kg; 95% CI: -0.14 to -0.06), low-fat milk (0.02 kg; 95% CI: -0.04 to 0.09) and whole milk (0.02 kg; 95% CI: -0.06 to 0.10). We estimated that replacement of 1 serving per day of SSBs by 1 cup per day of water was associated with 0.49 kg (95% CI: 0.32-0.65) less weight gain over each 4-year period, and the replacement estimate of fruit juices by water was 0.35 kg (95% CI: 0.23-0.46). Substitution of SSBs or fruit juices by other beverages (coffee, tea, diet beverages, low-fat and whole milk) were all significantly and inversely associated with weight gain.

CONCLUSION

Our results suggest that increasing water intake in place of SSBs or fruit juices is associated with lower long-term weight gain.

Erythrocyte trans-fatty acids, type 2 diabetes and cardiovascular risk factors in middle-aged and older Chinese individuals

AIMS/HYPOTHESIS

Few data are available about intakes and food sources of trans-fatty acids (TFAs) or their associations with cardiometabolic outcomes in Asian people who consume a prudent diet but are experiencing rapid nutritional transitions. We aimed to investigate the relationships between TFA biomarkers and type 2 diabetes and cardiovascular risk factors in Chinese individuals.

METHODS

Erythrocyte fatty acids were measured by gas chromatography among 3,107 men and women (50-70 years) recruited from urban and rural areas in Beijing and Shanghai, China.

RESULTS

Total trans-18:1 and two trans-18:2 isomers were detected and accounted for 0.37% of the total fatty acids in the erythrocytes. Concentrations of TFAs were higher in women than men, and in urban than rural residents. Of the TFAs, trans-18:1, but not trans-18:2, showed a modest association with dairy consumption (β = 0.27), but not with other foods. After adjustment for BMI, social-demographic, lifestyle and dietary factors and other TFAs, erythrocyte trans-18:1 was shown to be associated with a lower risk of type 2 diabetes (OR comparing extreme [first and fourth] quartiles 0.68, 95% CI 0.48, 0.97, p(trend) = 0.02), as well as 20-50% lower odds of central obesity, dyslipidaemia, hyperglycaemia, insulin resistance and chronic inflammation. In contrast, trans-18:2 fatty acids were positively associated with high triacylglycerol (p(trend) < 0.001) and LDL-cholesterol (p(trend) = 0.03) levels, but not with diabetes and other cardiometabolic risk factors.

CONCLUSIONS/INTERPRETATION

Among middle-aged and older Chinese individuals with overall low erythrocyte TFAs levels, trans-18:1 might serve as a marker of dairy intake. Higher trans-18:1 levels were associated with a lower risk of type 2 diabetes, whereas higher trans-18:2 levels were associated with dyslipidaemia.

Bidirectional association between depression and obesity in middle-aged and older women

OBJECTIVE

Although it has been hypothesized that the depression-obesity relation is bidirectional, few studies have addressed this hypothesis in a prospective setting. We aimed to examine the bidirectional relationship in middle-aged and elderly women.

SUBJECTS

A total of 65 955 women aged 54-79 years in the Nurses' Health Study were prospectively followed from 1996 to 2006 with updated information on body weight, depression status and various covariates every 2 years. Depression was defined as self-report of physician-diagnosed depression and/or antidepressant use. Obesity was defined as a BMI ≥30.0 kg m(-2). The first three waves (1996-2000) were used as the baseline period and the last three waves (2002-2006) were used as the follow-up period.

RESULTS

After adjusting for baseline age, physical activity, comorbidities, BMI and other covariates, depression at the baseline period was associated with an increased risk of obesity at the follow-up period in all women (multivariate-adjusted odds ratio (OR), 1.38; 95% confidence interval (95% CI), 1.24-1.53) and baseline non-obese women (OR, 1.51; 95% CI, 1.36-1.67). In the opposite direction, after adjusting for baseline age, physical activity, comorbidities, depression status and other covariates, obese women at baseline had a moderately increased risk of depression at the follow-up period compared with normal-weight women (OR, 1.11; 95% CI, 1.03-1.18), and this association was similar for new onset of depression (OR for obese versus normal weight women, 1.10; 95% CI, 1.02-1.20).

CONCLUSIONS

Our results suggest a bidirectional association between depression and obesity in middle-aged and elderly women. Future studies are needed to confirm our findings in different populations, and investigate the potential mechanisms underlying this association. Our results underscore the importance of early detection and proper behavioral modifications to lower the burden of both conditions.

Use of antidepressant medication and risk of type 2 diabetes: results from three cohorts of US adults

AIMS/HYPOTHESIS

The results of several studies have suggested a potential positive association between use of antidepressant medication (ADM) and incident type 2 diabetes mellitus. We examined this association in three cohorts of US adults.

METHODS

We followed 29,776 men in the Health Professionals Follow-up Study (HPFS, 1990-2006), 61,791 women in the Nurses' Health Study I (NHS I, 1996-2008) and 76,868 women in NHS II (1993-2005), who were free of diabetes mellitus, cardiovascular disease or cancer at baseline. The mean baseline ages for participants from the HPFS and NHS I and II were 56.4, 61.3 and 38.1 years, respectively. ADM use and other covariates were assessed at baseline and updated every 2 years. A time-dependent Cox proportional hazards model was used, and HRs were pooled together across the three cohorts.

RESULTS

During 1,644,679 person-years of follow-up, we documented 6,641 new cases of type 2 diabetes. ADM use was associated with an increased risk of diabetes in all three cohorts in age-adjusted models (pooled HR 1.68 [95% CI 1.27, 2.23]). The association was attenuated after adjustment for diabetes risk factors and histories of high cholesterol and hypertension (1.30 [1.14, 1.49]), and further attenuated by controlling for updated BMI (1.17 [1.09, 1.25]). Use of selective serotonin reuptake inhibitors and other antidepressants (mainly tricyclic antidepressants) were both associated with an elevated risk of diabetes, with pooled multivariate-adjusted HRs of 1.10 (1.00, 1.22) and 1.26 (1.11, 1.42), respectively.

CONCLUSIONS/INTERPRETATION

The results suggest that ADM users had a moderately elevated risk of type 2 diabetes mellitus compared with non-users, even after adjustment for BMI.

Nutritional and sensory profile of two Indian rice varieties with different degrees of polishing

Traditional hand-pounded rice has been replaced today with highly polished white rice in the Asian Indian diets. The study aimed to evaluate the nutritional as well as the sensory differences between the brown (0% polish) and the rice milled to different degrees of polish (2.3, 4.4 and 8.0%). Bapatla and Uma (red pigmented) varieties in both raw and parboiled forms were used. The protein, fat, dietary fibre, γ-oryzanol, polyphenols, vitamin E, total antioxidant activity and free radical scavenging abilities of the brown rice decreased while the available carbohydrates increased with polishing. Sensory attributes of the cooked rice samples (whiteness, grain intactness, fluffiness, firmness, stickiness, chewiness and the cooked rice aroma) were evaluated by trained panelists. Scores for branny taste and chewiness decreased with polishing. On the whole, brown rice of both the varieties was readily accepted by the well-informed sensory trained panelists.

Obesity is associated with higher risk of intensive care unit admission and death in influenza A (H1N1) patients: a systematic review and meta-analysis

The aim of this study was to assess the association between obesity and the risk of intensive care unit (ICU) admission and death among patients hospitalized for influenza A (H1N1) viral infection. A systematic review of the Medline and Cochrane databases using 'obesity', 'hospitalization', 'influenza A viral infection', various synonyms, and reference lists of retrieved articles from January 2009 to January 2010. Studies comparing the prevalence of obesity among patients with confirmed infection for influenza A virus and who were either hospitalized or admitted to ICU/died were included. A total of 3059 subjects from six cross-sectional studies, who were hospitalized for influenza A (H1N1) viral infection, were included in this meta-analysis. Severely obese H1N1 patients (body mass index ≥ 40 kg m(-2), n = 804) were as twice as likely to be admitted to ICU or die (odds ration: 2.01, 95% confidence interval: 1.29-3.14, P < 0.002) compared with H1N1 patients who were not severely obese. Having a body mass index ≥ 30 kg m(-2) was similarly associated with a more than twofold increased risk of ICU admission or death although this did not reach statistical significance (2.14, 0.92-4.99, P < 0.07). This meta-analysis supports the view that obesity is associated with higher risks of ICU admission or death in patients with influenza A (H1N1) infection. Therefore, morbid obese patients should be monitored more intensively when hospitalized.

Relative utility of 1-h Oral Glucose Tolerance Test as a measure of abnormal glucose homeostasis

BACKGROUND AND AIMS

Impaired glucose tolerance based on 2-h glucose levels is more predictive of future cardiovascular disease and more sensitive in detecting earlier diabetes compared to impaired fasting glucose. However, the 1-h OGTT may be even more sensitive than the 2-h. We assessed the relative value of 1-h OGTT by exploring its relationship with adiposity and other measures of glucose homeostasis.

METHODS AND RESULTS

Ninety four overweight/obese individuals free of diabetes and major cardiovascular conditions were included in the analyses. We adjusted for age, gender, smoking status and physical activity. One-h OGTT showed similar partial correlations with fasting glucose and 2-h OGTT (r=0.60 and 0.64 respectively). Fasting glucose, fasting insulin and HOMA correlated better with 1-h OGTT (r=0.60, 0.47 and 0.52) than with 2-h OGTT (r=0.50, 0.41, and 0.45). BMI and waist circumference also showed stronger correlation with 1-h (r=0.31, 0.29), compared to 2-h OGTT (r=0.16, 0.16) or fasting glucose (r=0.23, 0.22). Metabolic syndrome was associated similarly with 1-h and 2-h OGTT.

CONCLUSIONS

The 1-h OGTT correlates well with both fasting glucose and 2-h OGTT and shows similar or higher associations with obesity measures. The 1-h OGTT has potential utility in epidemiologic studies.

Preventing chronic diseases by promoting healthy diet and lifestyle: public policy implications for China

Fuelled by rapid urbanization and changes in dietary and lifestyle choices, chronic diseases have emerged as a critical public health issue in China. The Healthy China 2020 programme recently announced by the Chinese government has set an overarching goal of promoting public health and making health care accessible and affordable for all Chinese citizens by year 2020. One of important components of the programme is to reduce chronic diseases by promoting healthy eating and active lifestyles. Chronic diseases not only affect health and quality of life, but also have economical and social consequences. With a limited infrastructure for chronic disease care, China is ill-equipped to deal with the escalating chronic disease epidemic, which threatens to reverse the gains of economic development in recent decades. Population-based intervention studies conducted in China and elsewhere have demonstrated the efficacy and effectiveness of several preventive strategies to reduce risk of chronic diseases in high-risk individuals and the general population. However, translating these findings into practice requires changes in health systems and public policies. To achieve the goals set by the Healthy China 2020 programme, prevention of chronic diseases should be elevated to a national public policy priority.

Higher adiponectin levels predict greater weight gain in healthy women in the Nurses' Health Study

Adiponectin and resistin's possible roles in weight regulation have received little attention. We tested the hypothesis that adipokine levels predict future weight gain in women in the Nurses' Health Study. Among women who provided blood samples in 1990, we studied 1,063 women who did not develop diabetes ("healthy") and 984 women who subsequently developed diabetes. Total and high-molecular-weight (HMW) adiponectin and resistin levels were measured using enzyme-linked immunosorbent assay. Women who did not developed diabetes had a mean BMI of 26.3 ± 6.0 kg/m(2) at baseline and gained 2.0 ± 6.1 kg over 4 years. Women who developed diabetes had a mean BMI of 30.1 ± 5.4 kg/m(2) at baseline, and gained 2.4 ± 7.1 kg over 4 years. In women who did not developed diabetes, higher baseline levels of total and HMW adiponectin were associated with significantly greater weight gain after adjustment for age, BMI, physical activity, diet, and other covariates: women in the highest quintile of total adiponectin gained 3.18 kg compared to women in the lowest quintile who gained 0.80 kg (fully adjusted; P for trend <0.0001). Adiponectin was not significantly associated with weight gain in women who subsequently developed diabetes. Resistin levels were not associated with weight gain in either women who did or did not develop diabetes during the follow-up. We conclude that elevated adiponectin levels are associated with higher weight gain in healthy women, independent of confounding risk factors. High adiponectin production by adipocytes might be a sign of "healthy" adipose tissue with further capacity to store fat.

Combined effects of 17 common genetic variants on type 2 diabetes risk in a Han Chinese population

AIMS/HYPOTHESIS

The recent advent of genome-wide association studies has considerably accelerated the identification of type 2 diabetes loci. We aimed to investigate the combined effects of multiple genetic variants, alone or in combination with conventional risk factors, on type 2 diabetes and diabetes-related traits in Han Chinese.

METHODS

We genotyped 17 variants in 17 loci in a population-based Han Chinese cohort including 3,210 unrelated individuals. A genetic risk score (GRS) was calculated on the basis of these variants. The discriminatory ability was assessed by the area under the receiver operating characteristics curve.

RESULTS

The odds ratio for type 2 diabetes and hyperglycaemia with each GRS point (per risk allele) was 1.18 (95% CI 1.12-1.23, p = 1.3 x 10(-12)) and 1.12 (95% CI 1.09-1.16, p = 7.5 x 10(-14)), respectively. Compared with participants with GRS < or =11.0 (7.63%), those with GRS > or =19.0 (8.87%) had a 4.58-fold higher risk (95% CI 2.49-8.42) of type 2 diabetes. The GRS also showed a significant association with lower beta cell function estimated by HOMA of beta cell function (p = 8.4 x 10(-10)). In addition, we observed significant interactive effects between GRS and BMI on fasting glucose and HbA(1c) levels (p = 0.04 and p = 0.03 for interaction, respectively). Discrimination of diabetes risk was improved (p < 0.001) when the GRS was added to a model including clinical risk factors. The AUCs were 0.62 and 0.77, respectively, for the GRS and conventional clinic risk factors alone, and 0.79 when the GRS was added.

CONCLUSIONS/INTERPRETATION

In this Han Chinese population, the GRS of 17 combined variants modestly but significantly improved discrimination of the conventional risk factors for type 2 diabetes.

Life-course weight characteristics and the risk of gestational diabetes

AIMS/HYPOTHESIS

We prospectively determined the risk of gestational diabetes mellitus in association with life-course weight characteristics and adult abdominal adiposity.

METHODS

We investigated the joint and independent impact of birthweight, childhood size by somatotypes, adolescent and adult BMI, and abdominal adiposity on gestational diabetes mellitus risk among the 21,647 women in the Nurses' Health Study II who reported a singleton pregnancy between 1989 and 2001. A total of 1,386 incident cases of gestational diabetes mellitus were reported. Relative risk was estimated by pooled logistic regression adjusting for age, prematurity, race, smoking status, parental history of diabetes, age of first birth, parity and physical activity.

RESULTS

Birthweight was inversely associated with gestational diabetes mellitus risk (p = 0.02 for trend). Childhood somatotypes at ages 5 and 10 years were not associated with risk. U-shaped associations were found for BMI at age 18 years and somatotype at age 20 years. Weight gain between adolescence and adulthood, pre-gravid BMI and abdominal adiposity were positively associated with risk (p < 0.01 for all trends). Multivariate adjusted RRs for gestational diabetes from lowest to highest quintile of WHR were 1.00, 1.50, 1.51, 2.03, 2.12 (p = 0.0003 for trend). Lower birthweight (<7 lb) without adulthood overweight (BMI > 25 kg/m(2)) was associated with a 20% increased risk (95% CI 1.02-1.41). However, adulthood overweight alone was related to a 2.36 times greater risk (95% CI 2.12-3.77).

CONCLUSIONS/INTERPRETATION

Although lower birthweight is an independent risk factor for gestational diabetes mellitus, weight gain since early adulthood, and overall and central obesity in adulthood were more strongly associated with elevated risk of the condition independently of other known risk factors.

Lipid and inflammatory biomarkers and kidney function decline in type 2 diabetes

AIMS/HYPOTHESIS

Potentially modifiable biomarkers may influence the decline in estimated GFR (eGFR), but few data are currently available in type 2 diabetic adults.

METHODS

We studied 516 women with type 2 diabetes in the Nurses' Health Study with data on lipid and inflammatory biomarkers from plasma collected in 1989 and plasma creatinine in samples collected in 1989 and 2000. An estimated GFR decline of >or=25% over 11 years was the outcome of interest.

RESULTS

Comparing the highest with the lowest quartile, soluble tumour necrosis factor receptor 2 (sTNFR-2) was independently associated with an eGFR decline of >or=25% (multivariate OR 5.81; 95% CI 2.90-11.65); this association was stronger in obese women (OR 16.76; 95% CI 4.69-59.90 for BMI >or=30 kg/m(2); OR 2.78, 95% CI 1.12-6.89 for BMI <30 kg/m(2); p for interaction = 0.02). No lipids (total cholesterol, LDL-cholesterol, HDL-cholesterol, non-HDL-cholesterol, triacylglycerols, lipoprotein(a), or apolipoprotein B) or other markers of inflammation (C-reactive protein, fibrinogen, E-selectin, intracellular cell adhesion molecule 1, leptin or adiponectin) were significantly associated with eGFR decline after multivariable adjustment.

CONCLUSIONS/INTERPRETATION

Elevated sTNFR-2 levels may be an important and potentially modifiable risk factor for eGFR decline in type 2 diabetes, especially in those with a BMI of >or=30 kg/m(2).

Circulating IL-18 and the risk of type 2 diabetes in women

AIMS/HYPOTHESIS

The pathophysiology of type 2 diabetes involves pro-inflammatory pathways. We tested the hypothesis that IL-18 predicts future diabetes cases.

METHODS

We used a nested case-control design based in the Nurses' Health Study. Baseline blood samples were collected between 1989 and 1990. Questionnaires to assess body weight, lifestyle (physical activity, diet, smoking) and diabetes diagnosis were sent out and assessed biennially (follow-up until 2002). Cases (n = 1,012) were defined as women developing type 2 diabetes at least 1 year after blood sampling. Control women (n = 1,081) were matched to cases by age, date of blood draw, fasting status and race. We calculated the RR (95% CI) of type 2 diabetes in quintiles of IL-18 using conditional logistic regression with the first quintile as referent; adjustments included matching factors, diabetes risk factors, BMI, adipokine levels (adiponectin, resistin) and inflammatory proteins (C-reactive protein, tumour necrosis factor receptor 2 (TNFalpha-R2) and IL-6).

RESULTS

Higher IL-18 levels were associated with increased risk of developing diabetes, even after adjustment for matching factors and multiple diabetes risk factors: being in the highest quintile of IL-18 was associated with a RR of 1.75 (1.41-2.18) for diabetes relative to the first quintile (p < 0.0001 for trend). Significant trends in association were still observed after adjustment for BMI (RR 1.44 [1.15-1.80], p < 0.0001 for trend) and adiponectin levels (RR 1.28 [1.02-1.60], p = 0.006 for trend). Further adjustment for inflammatory markers in a sub-sample did not significantly change the results.

CONCLUSIONS/INTERPRETATION

Elevated IL-18 levels are associated with higher risk of diabetes. This association is independent of usual risk factors, including BMI and adipokine levels.

Physical activity patterns and prevention of weight gain in premenopausal women

BACKGROUND

Studies of the association between physical activity (PA) and weight maintenance have been inconsistent.

METHODS

We prospectively examined the association between PA patterns and prevention of weight gain among 46,754 healthy premenopausal women, aged 25–43 years in 1989. Participants reported their PA and weight in 1989 and 1997. The primary outcome was gaining >5% of baseline weight by 1997 (62% of the population).

RESULTS

Compared with women who maintained <30 minutes/day of total discretionary activity over 8 years, women were less likely to gain weight if they sustained 30+ minutes/day (Odds Ratio OR=0.68, 95% confidence interval [CI] 0.64–0.73) or increased to 30+ minutes/day in 1997 (OR=0.64, 95%CI=0.60–0.68). Among women whose only reported activity was walking, risk of gaining weight was lower in those who sustained 30+ minutes/day over 8 years (OR=0.66, 95%CI=0.49–0.91), and brisk walking pace independently predicted less weight gain. For a 30 minutes/day increase between 1989 and 1997, jogging/running was associated with less weight gain than brisk walking or other activities. Greater duration of PA was associated with progressively less weight gain, but even an 11–20 minutes/day increase was beneficial; the benefits appeared stronger among those initially overweight. Sedentary behavior independently predicted weight gain.

CONCLUSIONS

Sustained PA for at least 30 minutes/day, particularly if more intense, is associated with a reduction in long-term weight gain, and greater duration is associated with less weight gain. Sedentary women of any baseline weight who increase their PA will benefit, but overweight women appear to benefit the most.

Association of GCKR rs780094, alone or in combination with GCK rs1799884, with type 2 diabetes and related traits in a Han Chinese population

AIMS/HYPOTHESIS

The GCKR rs780094 and GCK rs1799884 polymorphisms have been reported to be associated with dyslipidaemia and type 2 diabetes in white Europeans. The aim of this study was to replicate these associations in Han Chinese individuals and to identify the potential mechanisms underlying these associations.

METHODS

The single nucleotide polymorphisms rs780094 and rs1799884 were genotyped in a population-based sample of Han Chinese individuals (n = 3,210) and tested for association with risk of type 2 diabetes and related phenotypes.

RESULTS

The GCKR rs780094 A allele was marginally associated with reduced risk of type 2 diabetes (OR 0.85, 95% CI 0.73-1.00, p value under an additive model [p((add))] = 0.05) and significantly associated with reduced risk of impaired fasting glucose (IFG) or type 2 diabetes (OR 0.86, 95% CI 0.77-0.96, p([add]) = 0.0032). It was also significantly associated with decreased fasting glucose and increased HOMA of beta cell function (HOMA-B) and fasting triacylglycerol levels (p([add]) = 0.0169-5.3 x 10(-6)), but not with HOMA of insulin sensitivity (HOMA-S). The associations with type 2 diabetes and IFG remained significant after adjustment for BMI, while adjustment for HOMA-B abolished the associations. The GCKR rs780094 was also associated with obesity and BMI, independently of its association with type 2 diabetes. The GCK rs1799884 A allele was significantly associated with decreased HOMA-B (p([add]) = 0.0005), but not with type 2 diabetes or IFG. Individuals with increasing numbers of risk alleles for both variants had significantly lower HOMA-B (p([add]) = 5.8 x 10(-5)) in the combined analysis.

CONCLUSIONS/INTERPRETATION

Consistent with observations in white Europeans, the GCKR rs780094 polymorphism contributes to the risk of type 2 diabetes and dyslipidaemia in Han Chinese individuals. In addition, we showed that the effect on type 2 diabetes is probably mediated through impaired beta cell function rather than through obesity.

Coffee consumption and risk of cardiovascular events and all-cause mortality among women with type 2 diabetes

AIMS/HYPOTHESIS

Coffee has been linked to both beneficial and harmful health effects, but data on its relationship with cardiovascular disease and mortality in patients with type 2 diabetes are sparse.

METHODS

This was a prospective cohort study including 7,170 women with diagnosed type 2 diabetes but free of cardiovascular disease or cancer at baseline. Coffee consumption was assessed in 1980 and then every 2-4 years using validated questionnaires. A total of 658 incident cardiovascular events (434 coronary heart disease and 224 stroke) and 734 deaths from all causes were documented between 1980 and 2004.

RESULTS

After adjustment for age, smoking and other cardiovascular risk factors, the relative risks were 0.76 (95% CI 0.50-1.14) for cardiovascular diseases (p trend = 0.09) and 0.80 (95% CI 0.55-1.14) for all-cause mortality (p trend = 0.05) for the consumption of >or=4 cups/day of caffeinated coffee compared with non-drinkers. Similarly, multivariable RRs were 0.96 (95% CI 0.66-1.38) for cardiovascular diseases (p trend = 0.84) and 0.76 (95% CI 0.54-1.07) for all-cause mortality (p trend = 0.08) for the consumption of >or=2 cups/day of decaffeinated coffee compared with non-drinkers. Higher decaffeinated coffee consumption was associated with lower concentrations of HbA(1c) (6.2% for >or=2 cups/day versus 6.7% for <1 cup/month; p trend = 0.02).

CONCLUSIONS

These data provide evidence that habitual coffee consumption is not associated with increased risk of cardiovascular diseases or premature mortality among diabetic women.

A prediction model for type 2 diabetes risk among Chinese people

AIMS/HYPOTHESIS

A range of prediction rules for the onset of type 2 diabetes have been proposed. However, most studies have been conducted in white groups and it is not clear whether these models apply to Asian populations. The purpose of this study was to construct a simple points model for predicting incident diabetes among Chinese people.

METHODS

We estimated the 10 year risk of diabetes in a cohort study of middle-aged and elderly participants who were free from diabetes at baseline. Cox regression coefficients were used to construct the simple points model and the discriminatory ability of the resulting prediction rule was determined using AUC and net reclassification improvement and integrated discrimination improvement statistics. Fivefold random splitting was used to test the internal validity and obtain bootstrap estimates of the AUC.

RESULTS

Of the 2,960 participants without diabetes at the baseline examination, 548 developed type 2 diabetes during a median 10 year follow-up period. Age (four points), elevated fasting glucose (11 points), body mass index (eight points), triacylglycerol (five points), white blood cell count (four points) and a higher HDL-cholesterol (negative four points) were found to strongly predict diabetes incidence in a multivariate model. The estimated AUC for the model was 0.702 (95% CI 0.676-0.727). This model performed better than existing prediction models developed in other populations, including the Prospective Cardiovascular Münster, Cambridge, San Antonia and Framingham models for diabetes risk.

CONCLUSIONS/INTERPRETATION

We have constructed a model for predicting the 10 year incidence of diabetes in Chinese people that could be useful for identifying individuals at high risk of diabetes in the Chinese population.

Gene-gene interactions between HNF4A and KCNJ11 in predicting Type 2 diabetes in women

AIMS

Recent studies indicate transcription factor hepatocyte nuclear factor 4 alpha (HNF-4 alpha, HNF4A) modulates the transcription of the pancreatic B-cell ATP-sensitive K+ (KATP) channel subunit Kir6.2 gene (KCNJ11). Both HNF4A and KCNJ11 have previously been associated with diabetes risk but little is known whether the variations in these genes interact with each other.

METHODS

We conducted a prospective, nested case-control study of 714 incident cases of Type 2 diabetes and 1120 control subjects from the Nurses' Health Study.

RESULTS

KCNJ11 E23K was significantly associated with an increased diabetes risk (odds ratio 1.26, 95% CI 1.03-1.53) while HNF4A P2 promoter polymorphisms were associated with a moderately increased risk at borderline significance. By using a logistic regression model, we found significant interactions between HNF4A rs2144908, rs4810424 and rs1884613 and KCNJ11 E23K (P for interaction = 0.017, 0.012 and 0.004, respectively). Carrying the minor alleles of the three HNF4A polymorphisms was associated with significantly greater diabetes risk in women carrying the KCNJ11 allele 23K, but not in those who did not carry this allele. Analyses using the multifactor dimensionality reduction (MDR) method confirmed the gene-gene interaction. We identified that the best interaction model included HNF4A rs2144908 and KCNJ11 E23K. Such a two-locus model showed the maximum cross-validation consistency of 10 out of 10 and a significant prediction accuracy of 54.2% (P = 0.01) on the basis of 1000-fold permutation testing.

CONCLUSIONS

Our data indicate that HNF4A P2 promoter polymorphisms may interact with KCNJ11 E23K in predicting Type 2 diabetes in women.

Circulating leptin levels are not associated with cardiovascular morbidity and mortality in women with diabetes: a prospective cohort study

AIMS/HYPOTHESIS

Leptin, an adipocyte-secreted hormone, plays an important role in regulating neuroendocrine and immune function as well as insulin resistance and metabolism. Our objective was to examine the relationship between leptin levels and cardiovascular morbidity and overall mortality in women with type 2 diabetes.

SUBJECTS AND METHODS

This prospective cohort study included 1,194 women with a confirmed diagnosis of type 2 diabetes, who provided a blood sample at baseline in 1989-1990. Participants were followed for 12 years for the development of health outcomes including cardiovascular disease (CVD) events as well as total mortality.

RESULTS

There were 218 new CVD events and 228 deaths from all causes. Cox proportional hazards analysis was used to estimate the relative risks (RRs) for each quintile level of leptin compared with the lowest quintile. Leptin levels were positively associated with several CVD risk factors including BMI and inflammatory markers, but were not independently associated with the incidence of CVD or total mortality in women with diabetes. The multivariate RRs (95% CIs) for CVD across the quintiles of leptin were 0.96 (0.61-1.53), 0.99 (0.61-1.61), 1.04 (0.63-1.71), 1.02 (0.59-1.75) (p for trend = 0.83).

CONCLUSIONS/INTERPRETATION

Although circulating leptin levels are associated with obesity and inflammatory markers, they are not significantly related to the risk of CVD or mortality in women with diabetes.

A prospective study of dietary patterns, meat intake and the risk of gestational diabetes mellitus

AIMS/HYPOTHESIS

The aim of this study was to prospectively examine whether dietary patterns are related to risk of gestational diabetes mellitus (GDM).

METHODS

This prospective cohort study included 13,110 women who were free of cardiovascular disease, cancer, type 2 diabetes and history of GDM. Subjects completed a validated semi-quantitative food frequency questionnaire in 1991, and reported at least one singleton pregnancy between 1992 and 1998 in the Nurses' Health Study II. Two major dietary patterns (i.e. 'prudent' and 'Western') were identified through factor analysis. The prudent pattern was characterised by a high intake of fruit, green leafy vegetables, poultry and fish, whereas the Western pattern was characterised by high intake of red meat, processed meat, refined grain products, sweets, French fries and pizza.

RESULTS

We documented 758 incident cases of GDM. After adjustment for age, parity, pre-pregnancy BMI and other covariates, the relative risk (RR) of GDM, comparing the highest with the lowest quintile of the Western pattern scores, was 1.63 (95% CI 1.20-2.21; p (trend)=0.001), whereas the RR comparing the lowest with the highest quintile of the prudent pattern scores was 1.39 (95% CI 1.08-1.80; p (trend)=0.018). The RR for each increment of one serving/day was 1.61 (95% CI 1.25-2.07) for red meat and 1.64 (95% CI 1.13-2.38) for processed meat.

CONCLUSIONS/INTERPRETATION

These findings suggest that pre-pregnancy dietary patterns may affect women's risk of developing GDM. A diet high in red and processed meat was associated with a significantly elevated risk.

Genetic variation in the hepatic lipase gene and the risk of coronary heart disease among US diabetic men: potential interaction with obesity

AIMS/HYPOTHESIS

The -514 C to T polymorphism of the hepatic lipase gene (LIPC) has been associated with lowered LIPC activity and elevated HDL-cholesterol concentrations. Previous findings on the association of this polymorphism with the risk of CHD are inconsistent. Moreover, data on this association among diabetic patients are limited. We investigated the association of the LIPC polymorphism with CHD risk among US diabetic men and evaluated whether this association was modified by adiposity status.

SUBJECTS AND METHODS

The case group consisted of 220 diabetic men who were recruited from the Health Professionals Follow-up Study (years 1986-2000) and were free of cardiovascular disease at baseline, but subsequently developed CHD. A total of 641 diabetic men from the same study but without cardiovascular disease constituted the control group.

RESULTS

No overall association between the LIPC polymorphism and CHD risk was observed. However, we did observe a significant interaction between this polymorphism and BMI in association with CHD risk. Among obese men, after adjustment for age, duration of diabetes and major lifestyle factors, the CT or TT genotype was associated with an increased CHD risk compared with the CC genotype (odds ratio [OR] 2.52, 95% CI 1.08-5.90); the corresponding ORs (95% CI) were 0.99 (0.58, 1.69) for overweight men (25< or =BMI <30 kg/m(2)) and 0.37 (0.17, 0.79) for lean men (BMI <25 kg/m(2)) (p for interaction 0.001). Stratified analyses by waist circumference (tertiles) showed a similar pattern of interaction (adjusted p for interaction 0.023).

CONCLUSION/INTERPRETATION

These data suggest that obesity may modify the association between the LIPC C(-514)T polymorphism and CHD risk among diabetic men.

The association of serum lipids and inflammatory biomarkers with renal function in men with type II diabetes mellitus

Dyslipidemia and inflammation may promote renal disease via mechanisms of vascular endothelial cell dysfunction in type II diabetes mellitus (DM). Sparse data, however, are available on the relation of lipids and inflammatory biomarkers and glomerular filtration rate (GFR) in type II DM. We performed a cross-sectional study of 732 men with type II DM enrolled in the Health Professionals' Follow-Up Study. Plasma creatinine was used to estimate GFR by the simplified Modification of Diet in Renal Disease (MDRD) equation. In men with a GFR <60 ml/min/1.73 m(2), triglycerides, non-high-density lipoprotein (HDL), apoprotein B, fibrinogen, soluble tumor necrosis factor receptor (sTNFR-2) and vascular cell adhesion molecule-1 (VCAM) were significantly higher when compared to the referent group (GFR> or =90 ml/min/1.73 m(2)). In multivariable logistic regression, those in the highest quartiles of the following biomarkers had increased odds of having a GFR <60 ml/min/1.73 m(2) when compared to those in the lowest quartiles: triglycerides (odds ratio (OR) 3.11; 95% CI, 1.52-6.36), fibrinogen (OR 5.40; 95% CI 2.14-13.65), sTNFR-2 (OR 8.34; 95% CI 3.50-19.88) and VCAM (OR 4.50; 95% CI 1.98-10.23). An inverse association was observed for HDL (OR 0.48; 95% CI 0.24-0.98). We found no association between C-reactive protein and GFR. The results were similar when creatinine clearance by Cockcroft-Gault was used to estimate kidney function. We conclude that several potentially modifiable lipid and inflammatory biomarkers are elevated in the setting of moderately decreased GFR in men with type II DM and may be the link between renal insufficiency and increased risk for cardiovascular events in this population.

Dietary patterns and risk of nonfatal acute myocardial infarction in Costa Rican adults

OBJECTIVE

To investigate the association between dietary patterns and risk of a first nonfatal acute myocardial infarction (MI) in Costa Rican adults.

DESIGN

Population-based case-control study.

SUBJECTS

A total of 496 incident MI cases and 518 population-based randomly selected controls matched to the cases by age (+/-5 years), gender, and county of residence. Subjects were interviewed with a validated food frequency questionnaire. Dietary patterns were identified by factor analysis. Odds ratios (OR) and 95% confidence intervals (CI) were obtained using multivariate conditional logistic regression adjusted for several recognized risk factors for MI.

RESULTS

Two diet patterns were identified, 'vegetable' characterized by increased intake of vegetables and fruits, and 'staple', characterized by an increased use of palm oil for cooking, and intake of refined grains (mostly white rice and white bread), legumes, coffee, added sugar, and red meat. Compared to the lowest quintile of the staple diet pattern, the highest quintile was associated with an increased risk of MI (OR: 3.70, 95% CI: 2.30-5.97). Adjusting for potential confounders did not change the results (OR: 3.53, 95% CI: 1.98-6.31). Consistently, an increasing staple pattern score was associated with lower HDL cholesterol (P for trend <0.02) and alpha-linolenic acid in adipose tissue (P for trend <0.0001). The vegetable pattern was not associated with MI.

CONCLUSIONS

The staple dietary pattern of Costa Rican adults is associated with low plasma HDL cholesterol, low alpha-linolenic acid in adipose tissue, and increased risk of MI.

Hyperproinsulinaemia and risk of Type 2 diabetes mellitus in women

AIMS

Our objective was to examine prospectively the associations between fasting plasma proinsulin and the proinsulin/insulin ratio and the incidence of Type 2 diabetes in women.

SUBJECTS AND METHODS

We designed a nested case-control study within the Nurses' Health Study, a cohort of 121,700 US women aged 30-55 years at study inception in 1976. Fasting plasma proinsulin, specific insulin and C-peptide levels were determined in 183 women with a new diagnosis of diabetes made after blood sampling between 1989 and 1990, and 369 control subjects without diabetes.

RESULTS

After adjustment for age, body mass index, family history of diabetes and other potential confounders, including HbA1c, the odds ratios for diabetes associated with increasing quartiles of proinsulin were 1.00, 0.85, 2.49 and 5.73 (P for trend: < 0.001). Proinsulin remained significantly associated with diabetes risk after adjusting for C-peptide and specific insulin (multivariate odds ratios for quartiles: 1.00, 0.78, 1.94, 3.69; P for trend = 0.001). In addition, the proinsulin/insulin ratio was significantly associated with diabetes risk, controlling in multivariate analysis for C-peptide (odds ratios for extreme quartiles: 2.48; 95% CI: 1.14-5.41; P for trend = 0.005).

CONCLUSIONS

These data suggest that proinsulin and the proinsulin/insulin ratio are strong independent predictors of diabetes risk, after adjustment for obesity and other potential confounders.

A prospective study of lipoprotein(a) and risk of coronary heart disease among women with type 2 diabetes

AIMS

We examined the association between lipoprotein (Lp)(a) and CHD among women with type 2 diabetes.

METHODS

Of 32,826 women from the Nurses' Health Study who provided blood at baseline, we followed 921 who had a confirmed diagnosis of type 2 diabetes.

RESULTS

During 10 years of follow-up (6,835 person-years), we documented 122 incident cases of CHD. After adjustment for age, smoking, BMI, glycosylated HbA(1)c, triglycerides (TGs), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and other cardiovascular risk factors, the relative risk (RR) comparing extreme quintiles of Lp(a) was 1.95 (95% CI 1.07-3.56). The association was not appreciably altered after further adjustment for apolipoprotein B(100) or several inflammatory biomarkers. Increasing levels of Lp(a) were associated with lower levels of TGs. The probability of developing CHD over 10 years was higher among diabetic women with substantially higher levels of both Lp(a) (>1.07 micromol/l) and TGs (>2.26 mmol/l) than among diabetic women with lower levels (22 vs 10%, p log-rank test=0.049). Diabetic women with a higher level of only Lp(a) or TGs had a similar (14%) risk. In a multivariate model, diabetic women with higher levels of Lp(a) and TGs had an RR of 2.46 (95% CI 1.21-5.01) for developing CHD, as compared with those with lower levels of both biomarkers (p for interaction=0.413). The RRs for women with a higher level of either Lp(a) (RR=1.22, 95% CI 0.77-1.92) or TGs (RR=1.39, 95% CI 0.78-2.42) were comparable.

CONCLUSIONS/INTERPRETATION

Increased levels of Lp(a) were independently associated with risk of CHD among diabetic women.

Changes in intake of fruits and vegetables in relation to risk of obesity and weight gain among middle-aged women

OBJECTIVE

To examine the changes in intake of fruits and vegetables in relation to risk of obesity and weight gain among middle-aged women.

DESIGN

Prospective cohort study with 12 y of follow-up conducted in the Nurses' Health Study.

SUBJECTS

A total of 74,063 female nurses aged 38-63 y, who were free of cardiovascular disease, cancer, and diabetes at baseline in 1984.

MEASUREMENTS

Dietary information was collected using a validated food frequency questionnaire, and body weight and height were self-reported.

RESULTS

During the 12-y follow-up, participants tended to gain weight with aging, but those with the largest increase in fruit and vegetable intake had a 24% of lower risk of becoming obese (BMI> or =30 kg/m2) compared with those who had the largest decrease in intake after adjustment for age, physical activity, smoking, total energy intake, and other lifestyle variables (relative risk (RR), 0.76; 95% confidence interval (CI), 0.69-0.86; P for trend <0.0001). For major weight gain (> or =25 kg), women with the largest increase in intake of fruits and vegetables had a 28% lower risk compared to those in the other extreme group (RR, 0.72; 95% CI, 0.55-0.93; P=0.01). Similar results were observed for changes in intake of fruits and vegetables when analyzed separately.

CONCLUSIONS

Our findings suggest that increasing intake of fruits and vegetables may reduce long-term risk of obesity and weight gain among middle-aged women.

Joint role of non-HDL cholesterol and glycated haemoglobin in predicting future coronary heart disease events among women with type 2 diabetes

AIMS/HYPOTHESIS

Non-HDL cholesterol (the sum of LDL, VLDL and IDL cholesterol) is considered to be particularly valuable in the management of dyslipidaemia in type 2 diabetes. However, it remains uncertain whether the association between non-HDL cholesterol and cardiovascular risk in type 2 diabetes depends on the status of hyperglycaemia. We aimed to determine whether non-HDL cholesterol predicts CHD events among diabetic women independently of currently established risk factors and the status of glycaemic control.

METHODS

We prospectively followed 921 diabetic women in the Nurses' Health Study, who were free of cardiovascular disease at the time that blood was drawn in 1989/90. During 10 years of follow-up, we identified 122 incident CHD cases.

RESULTS

After adjustment for age, BMI, smoking, alcohol consumption, and other lifestyle risk factors, the multivariate relative risks (RRs) of CHD for extreme quartiles were 1.97 (95% CI: 1.14-3.43) for non-HDL cholesterol, 1.78 (1.02-3.11) for apolipoprotein B-100, and 1.93 (1.15-3.22) for LDL cholesterol. However, the association between non-HDL cholesterol and CHD risk was only apparent among women with elevated fasting triglycerides (RR for extreme quartiles: 3.80; p=0.045). HbA(1)c was strongly associated with increased CHD risk (RR for increase by 1 unit: 1.24; 95% CI: 1.13-1.35), and both non-HDL cholesterol and HbA(1)c additively predicted CHD risk (RR for the combination of high non-HDL cholesterol and high HbA(1)c [tertiles]: 4.59).

CONCLUSIONS/INTERPRETATION

Our study suggests that non-HDL cholesterol and HbA(1)c are potent predictors of CHD risk in diabetic women. Therapies to lower CHD risk in diabetic patients should emphasise both glycaemic control and lipid lowering.

Moderate alcohol intake and markers of inflammation and endothelial dysfunction among diabetic men

AIMS/HYPOTHESIS

Type 2 diabetes mellitus is characterised by heightened inflammation and endothelial dysfunction. Moderate alcohol intake has been associated with a reduced risk of cardiovascular disease in type 2 diabetic patients. It remains to be determined whether there is an association between alcohol and inflammation in individuals with diabetes.

METHODS

We investigated the relationship between alcohol intake and inflammation in 726 of 18,159 men who returned blood samples in the Health Professionals Follow-up Study and had confirmed type 2 diabetes at blood draw.

RESULTS

In age-adjusted analyses, alcohol intake was associated with lower levels of HbA1c, fibrinogen, soluble tumour necrosis factor receptor-2 (sTNF-R2) and soluble vascular adhesion molecule-1 (sVCAM-1), and with higher levels of HDL cholesterol and adiponectin (p value for trends <0.05). After adjustment for age, HbA1c, insulin use, fasting status, smoking, BMI, physical activity, aspirin use, prevalence of cardiovascular disease and dietary factors, each additional drink per day was related to increased HDL cholesterol (0.053 mmol/l, p<0.0001) and adiponectin (0.8 microg/ml, p=0.01), and decreased sTNFR-2 (73 pg/ml, p=0.03), fibrinogen (0.302 micromol/l, p=0.02) and sVCAM-1 (33 ng/ml, p=0.02). The relationship between alcohol and inflammatory biomarkers persisted when subjects were stratified according to HbA1c levels.

CONCLUSIONS/INTERPRETATION

Moderate alcohol intake may have a beneficial effect on markers of inflammation and endothelial dysfunction in type 2 diabetic patients.

Phylloquinone intake as a marker for coronary heart disease risk but not stroke in women

OBJECTIVE

To examine the feasibility of using phylloquinone intake as a marker for coronary heart disease (CHD) and stroke risk in women.

DESIGN AND SETTING

Nurses' Health Study, a prospective cohort study during 1984-2000. Dietary data were collected in 1984, 1986, 1990, and 1994 using a validated semiquantitative food frequency questionnaire.

SUBJECTS

A total of 72 874 female nurses, aged 38-65 y, without previously diagnosed angina, myocardial infarction (MI), stroke, or cancer at baseline.

MAIN OUTCOME MEASURES

Incidence of nonfatal MI, CHD deaths, total CHD events, ischemic, and total strokes.

RESULTS

There were 1679 CHD events (1201 nonfatal) and 1009 strokes (567 ischemic). After adjustment for age and lifestyle factors associated with cardiovascular disease risk, the multivariate relative risks (RR) (95% CI) of total CHD from the lowest to the highest quintile category of phylloquinone intake were 1 (reference), 0.80 (0.69-0.94), 0.86 (0.74-1.00), 0.77 (0.66-0.99), and 0.79 (0.68-0.92), P for trend=0.01. Further adjustment for dietary intakes of saturated fat, polyunsaturated fat, trans fatty acids, eicosapentaenoic, and docosahexaenoic acids, cereal fiber, and folate attenuated the association (RR comparing extreme quintiles 0.84 [0.71-1.00], P for trend=0.12). Incidence rates of total or ischemic strokes were not associated with phylloquinone intake.

CONCLUSION

The data suggest that high phylloquinone intake may be a marker for low CHD risk. Dietary and lifestyle patterns associated with phylloquinone intakes, rather than intake of the nutrient itself, might account for all or part of the weak association. .

Processed meat intake and incidence of Type 2 diabetes in younger and middle-aged women

AIM/HYPOTHESIS

The aim of this study was to investigate the association between processed and other meat intake and incidence of Type 2 diabetes in a large cohort of women.

METHODS

Incident cases of Type 2 diabetes were identified during 8 years of follow-up in a prospective cohort study of 91246 U.S. women aged 26 to 46 years and being free of diabetes and other major chronic diseases at baseline in 1991.

RESULTS

We identified 741 incident cases of confirmed Type 2 diabetes during 716276 person-years of follow-up. The relative risk adjusted for potential non-dietary confounders was 1.91 (95% CI: 1.42-2.57) in women consuming processed meat five times or more a week compared with those consuming processed meat less than once a week ( p<0.001 for trend). Further adjustment for intakes of magnesium, cereal fibre, glycaemic index, and caffeine or for a Western dietary pattern did not appreciably change the results and associations remained strong after further adjustment for fatty acid and cholesterol intake. Frequent consumption of bacon, hot dogs, and sausage was each associated with an increased risk of diabetes. While total red meat (beef or lamb as main dish, pork as main dish, hamburger, beef, pork or lamb as sandwich or mixed dish) intake was associated with an increased risk of diabetes, this association was attenuated after adjustment for magnesium, cereal fiber, glycaemic index, and caffeine (relative risk: 1.44; 95% CI: 0.92-2.24).

CONCLUSION/INTERPRETATION

Our data suggest that diets high in processed meats could increase the risk for developing Type 2 diabetes.

Time trends of obesity in pre-school children in China from 1989 to 1997

OBJECTIVE

To examine predictors and time trends of obesity in pre-school children in China.

DESIGN

This study was based on data from China Health and Nutrition Survey, a longitudinal survey from 1989 to 1997.

SUBJECTS

For cross-sectional analysis, we included 944, 1058, 903 and 483 children aged 2-6 y in 1989, 1991, 1993 and 1997, respectively. For longitudinal analysis, we included 944 children and 3146 measurements during four time periods.

MEASURES

Overweight and obesity according to age- and sex-specific BMI cut-off points proposed by International Obesity Task Force.

RESULTS

The overall prevalence of obesity increased from 4.2% in 1989 to 6.4% in 1997 among children aged 2-6 y. The increase largely occurred in urban areas, where the prevalence of obesity increased from 1.5% in 1989 to 12.6% in 1997 and prevalence of overweight increased from 14.6 to 28.9% at the same period. Longitudinal analysis shows BMI increased by 0.2 kg/m2 per year in urban areas and 0.1 kg/m2 per year in rural areas. In multivariate analysis, overweight in early childhood (2-6 y), parental overweight, high income and urban areas independently predicted overweight at age 10-14 y.

CONCLUSION

A substantial increase in overweight and obesity among children aged 2-6 y was observed in urban areas in China from 1989 to 1997. Overweight in early childhood significantly predicted overweight during adolescence. Urgent public health strategies are needed to prevent childhood obesity in China.

Prospective study of major dietary patterns and colorectal cancer risk in women

A number of prospective cohort studies have examined the relations of individual dietary variables to risk of colorectal cancer. Few studies have addressed the broader eating patterns that reflect many dietary exposures working together. Using data from a prospective study of 61,463 women, with an average follow-up period of 9.6 years (between 1987 and 1998) and 460 incident cases of colorectal cancer, the authors conducted a factor analysis to identify and examine major dietary patterns in relation to colorectal cancer risk. Using proportional hazards regression to estimate relative risks, the authors found no clear association between a "Western," "healthy," or "drinker" dietary pattern and colorectal cancer risk. However, the data suggested that consuming low amounts of foods that constitute a "healthy" dietary pattern may be associated with increased risks of colon and rectal cancers. An inverse association with the "healthy" dietary pattern was found among women under age 50 years, although the number of cancers in this age group was limited and interpretation of this finding should be cautious. In this age group, relative risks for women in increasing quintiles of the "healthy" dietary pattern, compared with the lowest quintile, were 0.74 (95% confidence interval (CI): 0.41, 1.31), 0.69 (95% CI: 0.39, 1.24), 0.59 (95% CI: 0.32, 1.07), and 0.45 (95% CI: 0.23, 0.88) (p for trend = 0.03). The role of overall eating patterns in predicting colorectal cancer risk requires further investigation.

A prospective study of major dietary patterns and the risk of breast cancer

Our aim was to study the broader eating patterns that potentially reflect many dietary exposures working together in their association with breast cancer risk. Using data from a prospective study of 61,463 women with an average follow-up of 9.6 years and 1,328 incident cases of breast cancer, we conducted a factor analysis to identify major dietary patterns. Proportional hazards regression was used to estimate hazard ratios. We found no association between the "Western" dietary pattern (characterized by such foods as red and processed meats, refined grains, fat, and sweets) or the "healthy" dietary pattern (fruit and vegetables, fish and poultry, low-fat dairy, and whole grains) and breast cancer risk. However, women who were in the highest category of the "drinker" dietary pattern (wine, beer, and spirits) had a moderately increased risk (rate ratio = 1.27; 95% confidence interval, 1.06-1.52; P for trend, 0.002). The positive association was somewhat weaker among women below 50 years of age, a finding not inconsistent with chance. Our results are in agreement with the majority of previous studies that show alcohol consumption moderately increases the risk of breast cancer, but our results do not support any association between breast cancer risk and the "Western" or "healthy" dietary patterns.