Protein,iron, and meat consumption and risk for rheumatoid arthritis: a prospective cohort study

A recent prospective study showed that higher consumption of red meat and total protein was associated with increased risk for inflammatory polyarthritis. We therefore prospectively examined the relationship between diet (in particular, protein, iron, and corresponding food sources) and incident rheumatoid arthritis (RA) among 82,063 women in the Nurses' Health Study. From 1980 to 2002, 546 incident cases of RA were confirmed by a connective tissue disease screening questionnaire and medical record review for American College of Rheumatology criteria for RA. Diet was assessed at baseline in 1980 and five additional times during follow up. We conducted Cox proportional hazards analyses to calculate the rate ratio of RA associated with intakes of protein (total, animal, and vegetable) and iron (total, dietary, from supplements, and heme iron) and their primary food sources, adjusting for age, smoking, body mass index, and reproductive factors. The multivariate models revealed no association between RA and any measure of protein or iron intake. In comparisons of highest with lowest quintiles of intake, the rate ratio for total protein was 1.17 (95% confidence interval 0.89–1.54; P for trend = 0.11) and for total iron it was 1.04 (95% confidence interval 0.77–1.41; P for trend = 0.82). Red meat, poultry, and fish were also not associated with RA risk. We were unable to confirm that there is an association between protein or meat and risk for RA in this large female cohort. Iron was also not associated with RA in this cohort.     

Serum copper-to-zinc ratio and risk of incident pneumonia in caucasian men: a prospective cohort study

BioMetals - Serum copper (Cu) and zinc (Zn), essential micronutrients that have important immunomodulatory and antimicrobial properties, are biomarkers of ageing. Serum Cu/Zn-ratio may be a more...     

Association between muscular strength and mortality in men: prospective cohort study

Objective To examine prospectively the association between muscular strength and mortality from all causes, cardiovascular disease, and cancer in men.Design Prospective cohort study.Setting Aerobics centre longitudinal study.Participants 8762 men aged 20-80.Main outcome measures All cause mortality up to 31 December 2003; muscular strength, quantified by combining one repetition maximal measures for leg and bench presses and further categorised as age specific thirds of the combined strength variable; and cardiorespiratory fitness assessed by a maximal exercise test on a treadmill.Results During an average follow-up of 18.9 years, 503 deaths occurred (145 cardiovascular disease, 199 cancer). Age adjusted death rates per 10 000 person years across incremental thirds of muscular strength were 38.9, 25.9, and 26.6 for all causes; 12.1, 7.6, and 6.6 for cardiovascular disease; and 6.1, 4.9, and 4.2 for cancer (all P<0.01 for linear trend). After adjusting for age, physical activity, smoking, alcohol intake, body mass index, baseline medical conditions, and family history of cardiovascular disease, hazard ratios across incremental thirds of muscular strength for all cause mortality were 1.0 (referent), 0.72 (95% confidence interval 0.58 to 0.90), and 0.77 (0.62 to 0.96); for death from cardiovascular disease were 1.0 (referent), 0.74 (0.50 to 1.10), and 0.71 (0.47 to 1.07); and for death from cancer were 1.0 (referent), 0.72 (0.51 to 1.00), and 0.68 (0.48 to 0.97). The pattern of the association between muscular strength and death from all causes and cancer persisted after further adjustment for cardiorespiratory fitness; however, the association between muscular strength and death from cardiovascular disease was attenuated after further adjustment for cardiorespiratory fitness.Conclusion Muscular strength is inversely and independently associated with death from all causes and cancer in men, even after adjusting for cardiorespiratory fitness and other potential confounders.     

Low consumption of seafood in early pregnancy as a risk factor for preterm delivery: prospective cohort study

Objective To determine the relation between intake of seafood in pregnancy and risk of preterm delivery and low birth weight.DesignProspective cohort study.Setting Aarhus, Denmark.Participants8729 pregnant women.Results The occurrence of preterm delivery differed significantly across four groups of seafood intake, falling progressively from 7.1% in the group never consuming fish to 1.9% in the group consuming fish as a hot meal and an open sandwich with fish at least once a week. Adjusted odds for preterm delivery were increased by a factor of 3.6 (95% confidence interval 1.2 to 11.2) in the zero consumption group compared with the highest consumption group. Analyses based on quantified intakes indicated that the working range of the dose-response relation is mainly from zero intake up to a daily intake of 15 g fish or 0.15 g n-3 fatty acids. Estimates of risk for low birth weight were similar to those for preterm delivery.Conclusions Low consumption of fish was a strong risk factor for preterm delivery and low birth weight. In women with zero or low intake of fish, small amounts of n-3 fatty acids—provided as fish or fish oil—may confer protection against preterm delivery and low birth weight.

What is already known on this topic

Long chain n-3 fatty acids in amounts above 2 g a day may delay spontaneous delivery and prevent recurrence of preterm deliveryLarge studies have not been carried out to determine to what extent low consumption of n-3 fatty acids is a risk factor for preterm deliveryThe dose-response relation has not been described

What this study adds

Low consumption of fish seems to be a strong risk factor for preterm delivery and low birth weight in Danish womenThis relation is strongest below an estimated daily intake of 0.15 g long chain n-3 fatty acids or 15 g fish     

High-normal blood pressure and long-term risk of type 2 diabetes: 35-year prospective population based cohort study of men

Background

Atrial fibrillation is the most common type of arrhythmia after cardiac surgery. An increasing body of evidence demonstrates that oxidative stress plays a pivotal role in the pathophysiology of atrial fibrillation. N-acetylcysteine (NAC) is a free radical scavenger, and may attenuate this pathophysiologic response and reduce the incidence of postoperative AF (POAF). However, it is unclear whether NAC could effectively prevent POAF. Therefore, this meta-analysis aims to assess the efficacy of NAC supplementation on the prevention of POAF.

Methods

Medline and Embase were systematically reviewed for studies published up to November 2011, in which NAC was compared with controls for adult patients undergoing cardiac surgery. Outcome measures comprised the incidence of POAF and hospital length of stay (LOS). The meta-analysis was performed with the fixed-effect model or random-effect model according to the heterogeneity.

Results

Eight randomized trials incorporating 578 patients provided the best evidence and were included in this meta-analysis. NAC supplementation significantly reduced the incidence of POAF (OR 0.62, 95% CI 0.41 to 0.93; P = 0.021) compared with controls, but had no effect on LOS (WMD -0.07, 95% CI -0.42 to 0.28; P = 0.703).

Conclusions

The prophylactic NAC supplementation may effectively reduce the incidence of POAF. However, the overall quality of current studies is poor and further research should focus on adequately powered randomized controlled trials with POAF incidence as a primary outcome measure.     

Adherence to Mediterranean diet and risk of developing diabetes: prospective cohort study

Objective To assess the relation between adherence to a Mediterranean diet and the incidence of diabetes among initially healthy participants.Design Prospective cohort study with estimates of relative risk adjusted for sex, age, years of university education, total energy intake, body mass index, physical activity, sedentary habits, smoking, family history of diabetes, and personal history of hypertension.Setting Spanish university department.Participants 13 380 Spanish university graduates without diabetes at baseline followed up for a median of 4.4 years.Main outcome measures Dietary habits assessed at baseline with a validated 136 item food frequency questionnaire and scored on a nine point index. New cases of diabetes confirmed through medical reports and an additional detailed questionnaire posted to those who self reported a new diagnosis of diabetes by a doctor during follow-up. Confirmed cases of type 2 diabetes.Results Participants who adhered closely to a Mediterranean diet had a lower risk of diabetes. The incidence rate ratios adjusted for sex and age were 0.41 (95% confidence interval 0.19 to 0.87) for those with moderate adherence (score 3-6) and 0.17 (0.04 to 0.75) for those with the highest adherence (score 7-9) compared with those with low adherence (score <3). In the fully adjusted analyses the results were similar. A two point increase in the score was associated with a 35% relative reduction in the risk of diabetes (incidence rate ratio 0.65, 0.44 to 0.95), with a significant inverse linear trend (P=0.04) in the multivariate analysis.Conclusion Adherence to a Mediterranean diet is associated with a reduced risk of diabetes.     

Anthropometric features and cutaneous melanoma risk: A prospective cohort study in French women

BackgroundEpidemiological studies on anthropometric features and cutaneous melanoma risk in women yielded inconsistent results, with few analyses involving prospective cohort data. Our objective was to explore several anthropometric characteristics in relation to the risk of melanoma in women.MethodsWe prospectively analysed data from E3N, a French cohort involving 98,995 women born in 1925–1950. Participants completed self-administered questionnaires sent biennially over 1990–2008. Relative risks (RRs) and 95% confidence intervals (CIs) were computed using Cox proportional hazards regression models, adjusted for age, number of naevi, freckling, skin and hair colour, skin sensitivity to sun exposure, residential sun exposure, and physical activity.ResultsHeight was positively associated with melanoma in age-adjusted models only (RR = 1.27, 95% CI = 1.05–1.55 for ≥164 cm vs. <160 cm; P for trend = 0.02). After full adjustment, there was a significantly positive relationship between sitting-to-standing height ratio and melanoma risk (RR = 1.40, 95% CI = 1.06–1.86 for ≥0.533 vs. <0.518; P for trend = 0.02). A large body shape at menarche was inversely associated with the risk of melanoma (RR = 0.78, 95% CI = 0.62–0.98; compared with lean). However, weight, body mass index, body surface area, waist or hip circumference, sitting height or leg length were not significantly associated with risk.ConclusionThese results suggest that height, sitting-to-standing height ratio and body shape at menarche may be associated with melanoma risk. Further research is required to confirm these relationships and better understand the underlying mechanisms.     

A prospective study of aspirin use and the risk of gastrointestinal bleeding in men

Background and Aims

Data regarding the influence of dose and duration of aspirin use on risk of gastrointestinal bleeding are conflicting.

Methods

We conducted a prospective cohort study of 32,989 men enrolled in the Health Professionals Follow-up Study (HPFS) in 1994 who provided biennial aspirin data. We estimated relative risk of major gastrointestinal bleeding requiring hospitalization or a blood transfusion.

Results

During 14 years of follow-up, 707 men reported an episode of major gastrointestinal bleeding over 377,231 person-years. After adjusting for risk factors, regular aspirin use (≥2 times/week) had a multivariate relative risk (RR) of gastrointestinal bleeding of 1.32 (95% confidence interval [CI], 1.12–1.55) compared to non-regular use. The association was particularly evident for upper gastrointestinal bleeding (multivariate RR, 1.49; 95% CI, 1.16–1.92). Compared to men who denied any aspirin use, multivariate RRs of upper gastrointestinal bleeding were 1.05 (95% CI 0.71–1.52) for men who used 0.5–1.5 standard tablets/week, 1.31 (95% CI 0.88–1.95) for 2–5 aspirin/week, 1.63 (95% CI, 1.15–2.32) for 6–14 aspirin/week and 2.40 (95% CI, 1.10–5.22) for >14 aspirin/week (P_trend<0.001). The relative risk also appeared to be dose-dependent among short-term users <5 years; P_trend<.001) and long-term users (≥5 years; P_trend = 0.015). In contrast, after controlling for dose, increasing duration of use did not appear to be associated with risk (P_trend = 0.749).

Conclusions

Regular aspirin use increases the risk of gastrointestinal bleeding, especially from the upper tract. However, risk of bleeding appears to be more strongly related to dose than to duration of use. Risk of bleeding should be minimized by using the lowest effective dose among short-term and long-term aspirin users.     

Work stress and risk of cardiovascular mortality: prospective cohort study of industrial employees

ObjectiveTo examine the association between work stress, according to the job strain model and the effort-reward imbalance model, and the risk of death from cardiovascular disease.DesignProspective cohort study. Baseline examination in 1973 determined cases of cardiovascular disease, behavioural and biological risks, and stressful characteristics of work. Biological risks were measured at 5 year and 10 year follow up.SettingStaff of a company in the metal industry in Finland.Participants812 employees (545 men, 267 women) who were free from cardiovascular diseases at baseline.ResultsMean length of follow up was 25.6 years. After adjustment for age and sex, employees with high job strain, a combination of high demands at work and low job control, had a 2.2-fold (95% confidence interval 1.2 to 4.2) cardiovascular mortality risk compared with their colleagues with low job strain. The corresponding risk ratio for employees with effort-reward imbalance (low salary, lack of social approval, and few career opportunities relative to efforts required at work) was 2.4 (1.3 to 4.4). These ratios remained significant after additional adjustment for occupational group and biological and behavioural risks at baseline. High job strain was associated with increased serum total cholesterol at the 5 year follow up. Effort-reward imbalance predicted increased body mass index at the 10 year follow up.ConclusionsHigh job strain and effort-reward imbalance seem to increase the risk of cardiovascular mortality. The evidence from industrial employees suggests that attention should be paid to the prevention of work stress.

What is already known on this topic

Job strain (high demands and low job control) and effort-reward imbalance (high demands, low security, few career opportunities) elicit stress at workTheir status as risk factors for cardiovascular mortality has, however, remained uncertain

What this study adds

Job strain and effort-reward imbalance were each associated with a doubling of the risk of cardiovascular death among employees who were free from overt cardiovascular diseases at baselineJob strain and effort-reward imbalance also predicted adverse changes in biological factors such as cholesterol concentration and body mass index     

Alcohol consumption, genetic variants in alcohol deydrogenases, and risk of cardiovascular diseases: a prospective study and meta-analysis

Objective

First, to investigate and compare associations between alcohol consumption and variants in alcohol dehydrogenase (ADH) genes with incidence of cardiovascular diseases (CVD) in a large German cohort. Second, to quantitatively summarize available evidence of prospective studies on polymorphisms in ADH1B and ADH1C and CVD-risk.

Methods

We conducted a case-cohort study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort including a randomly drawn subcohort (n = 2175) and incident cases of myocardial infarction (MI; n = 230) or stroke (n = 208). Mean follow-up time was 8.2±2.2 years. The association between alcohol consumption, ADH1B or ADH1C genotypes, and CVD-risk was assessed using Cox proportional hazards regression. Additionally, we report results on associations of variants in ADH1B and ADH1C with ischemic heart disease and stroke in the context of a meta-analysis of previously published prospective studies published up to November 2011.

Results

Compared to individuals who drank >0 to 6 g alcohol/d, we observed a reduced risk of MI among females consuming >12 g alcohol/d (HR = 0.31; 95% CI: 0.10–0.97) and among males consuming >24 to 60 g/d (HR = 0.57; 95% CI: 0.33–0.98) or >60 g alcohol/d (HR = 0.30; 95% CI: 0.12–0.78). Stroke risk was not significantly related to alcohol consumption >6 g/d, but we observed an increased risk of stroke in men reporting no alcohol consumption. Individuals with the slow-coding ADH1B*1/1 genotype reported higher median alcohol consumption. Yet, polymorphisms in ADH1B or ADH1C were not significantly associated with risk of CVD in our data and after pooling results of eligible prospective studies [ADH1B*1/1: RR = 1.35 (95% CI: 0.98–1.88; p for heterogeneity: 0.364); ADH1C*2/2: RR = 1.07 (95% CI: 0.90–1.27; p for heterogeneity: 0.098)].

Conclusion

The well described association between alcohol consumption and CVD-risk is not reflected by ADH polymorphisms, which modify the rate of ethanol oxidation.     

Alcohol consumption and mortality from all causes,coronary heart disease,and stroke: results from a prospective cohort study of Scottish men with 21 years of follow up

ObjectivesTo relate alcohol consumption to mortality.DesignProspective cohort study.Setting27 workplaces in the west of Scotland.Participants5766 men aged 35-64 when screened in 1970-3 who answered questions on their usual weekly alcohol consumption.ResultsRisk for all cause mortality was similar for non-drinkers and men drinking up to 14 units a week. Mortality risk then showed a graded association with alcohol consumption (relative rate compared with non-drinkers 1.34 (95% confidence interval 1.14 to 1.58) for 15-21 units a week, 1.49 (1.27 to 1.75) for 22-34 units, 1.74 (1.47 to 2.06) for 35 or more units). Adjustment for risk factors attenuated the increased relative risks, but they remained significantly above 1 for men drinking 22 or more units a week. There was no strong relation between alcohol consumption and mortality from coronary heart disease after adjustment. A strong positive relation was seen between alcohol consumption and risk of mortality from stroke, with men drinking 35 or more units having double the risk of non-drinkers, even after adjustment.ConclusionsThe overall association between alcohol consumption and mortality is unfavourable for men drinking over 22 units a week, and there is no clear evidence of any protective effect for men drinking less than this.

Key messages

• Results from a large cohort study of employed Scottish men showed different relations between alcohol consumption and mortality than previous studies
• There was no relation between mortality from coronary heart disease and alcohol consumption once adjustments were made for potential confounding factors
• There was a strong relation with mortality from stroke; drinkers of over 35 units a week had double the risk of mortality compared with non-drinkers
• Some but not all of this could be accounted for by alcohol related increases in blood pressure
• Overall, risk of all cause mortality was higher in men drinking 22 or more units a week

     

Alcohol consumption at midlife and successful ageing in women: a prospective cohort analysis in the nurses' health study

Background

Observational studies have documented inverse associations between moderate alcohol consumption and risk of premature death. It is largely unknown whether moderate alcohol intake is also associated with overall health and well-being among populations who have survived to older age. In this study, we prospectively examined alcohol use assessed at midlife in relation to successful ageing in a cohort of US women.

Methods and Findings

Alcohol consumption at midlife was assessed using a validated food frequency questionnaire. Subsequently, successful ageing was defined in 13,894 Nurses'' Health Study participants who survived to age 70 or older, and whose health status was continuously updated. “Successful ageing” was considered as being free of 11 major chronic diseases and having no major cognitive impairment, physical impairment, or mental health limitations. Analyses were restricted to the 98.1% of participants who were not heavier drinkers (>45 g/d) at midlife. Of all eligible study participants, 1,491 (10.7%) achieved successful ageing. After multivariable adjustment of potential confounders, light-to-moderate alcohol consumption at midlife was associated with modestly increased odds of successful ageing. The odds ratios (95% confidence interval) were 1.0 (referent) for nondrinkers, 1.11 (0.96–1.29) for ≤5.0 g/d, 1.19 (1.01–1.40) for 5.1–15.0 g/d, 1.28 (1.03–1.58) for 15.1–30.0 g/d, and 1.24 (0.87–1.76) for 30.1–45.0 g/d. Meanwhile, independent of total alcohol intake, participants who drank alcohol at regular patterns throughout the week, rather than on a single occasion, had somewhat better odds of successful ageing; for example, the odds ratios (95% confidence interval) were 1.29 (1.01–1.64) and 1.47 (1.14–1.90) for those drinking 3–4 days and 5–7 days per week in comparison with nondrinkers, respectively, whereas the odds ratio was 1.10 (0.94–1.30) for those drinking only 1–2 days per week.

Conclusions

These data suggest that regular, moderate consumption of alcohol at midlife may be related to a modest increase in overall health status among women who survive to older ages. Please see later in the article for the Editors'' Summary     

Appendectomy and the subsequent risk of cancer: A prospective population-based cohort study with long follow-up

BackgroundThe appendix, an organ of immunological and microbiological importance, could be involved in the pathogenesis of cancers, but results are inconclusive. Our objective was to assess the association between appendectomy and the subsequent risk of cancer.MethodsData were obtained from the Rotterdam Study; a long-term prospective population-based study of individuals aged 55 years and older, of which the first cohort started in 1990 and included 7983 participants. Information on appendectomy was obtained through either medical interview at baseline or linkage with the national automated pathology center (PALGA). Cancer cases were pathology based. End of follow-up was January 1st, 2015. The association between appendectomy and risk of cancer was assessed using Cox proportional hazard models, adjusted for known confounders.ResultsOf 7135 included participants, 1373 (19.2%) had undergone an appendectomy and 1632 individuals developed cancer. After adjustment for age, sex, socioeconomic status, BMI, smoking, prevalent diabetes mellitus and alcohol intake, a history of appendectomy was associated with a significantly lower risk of cancer [hazard ratio (HR) 0.86, 95% confidence interval (CI) 0.75-0.98]. Subgroup analyses showed similar results for gastrointestinal cancer (HR 0.75, 95% CI 0.56-0.99), in particular colon cancer (HR 0.65, 95% 0.43-0.97), and cancer of the female reproductive organs (HR 0.35, 95% CI 0.15-0.80).ConclusionParticipants who underwent an appendectomy had a reduced risk of cancer in general after adjustment for potential confounders. Therefore, these results contradict earlier studies suggestive of an increased risk. Further research is necessary to replicate these results and reveal its underlying mechanism.     

Smoking and other risk factors for pancreatic cancer: A cohort study in men in Lithuania

Background: Cancer of the pancreas is a relatively rare, but highly fatal cancer worldwide. Cigarette smoking has been recognized as an important risk factor, but the relation to other potential determinants is still inconsistent. We investigated the association between different lifestyle, biological and anthropometric factors and the risk of pancreatic cancer in a prospective population-based cohort study from Kaunas, Lithuania. Methods: Our study included 7132 urban men initially free from any diagnosed cancer, followed for up to 30 years. 77 incident cases of pancreatic cancer were identified. Cox proportional hazards regression models were used to estimate hazard ratios (HR) and corresponding 95% confidence intervals (95% CI). Results: Compared to never smokers, current smokers had a significantly increased risk of pancreatic cancer, HR was 1.79 (95% CI 1.03–3.09) after adjustment for age, body mass index, education and alcohol consumption. Among smokers, a significant association with higher smoking intensity was shown (≥20 cigarettes/day: HR = 2.60; 95% CI 1.42–4.76, P_trend = 0.046). We also observed a significantly increased risk for ≥30 pack-years of smoking (HR = 2.24; 95% CI 1.12–4.49, P_trend = 0.16) and for age at starting smoking <18 years (HR = 2.29; 95% CI 1.11–4.70, P_trend = 0.43) as compared to never smokers. Alcohol consumption, body mass index and total cholesterol level were not significantly associated with pancreatic cancer. Conclusions: Smoking significantly increases pancreatic cancer incidence and its high prevalence in Lithuania may partly explain high incidence of the disease. No convincing evidence was found that alcohol consumption, body mass index or serum cholesterol level were associated with pancreatic cancer risk, although the assessment was limited by the lack of statistical power.     

Pre-existing risk factor profiles in users and non-users of hormone replacement therapy: prospective cohort study in Gothenburg,Sweden

ObjectiveTo assess whether risk factor profiles for cardiovascular disease differed, before starting treatment, between women who would subsequently use hormone replacement therapy and those who would remain untreated.DesignProspective population study, initiated in 1968-9, with follow ups in 1974, 1980, and 1992.SettingGothenburg, Sweden.Participants1201 women born in 1918, 1922, and 1930, representative of women of the same age in the general population.Results179 of the 1202 women (14.9%) used hormone replacement therapy sometime during the 24 year follow up period. Multivariate models indicated that these women had significantly lower blood pressure, had less obesity, and belonged to a higher social group before the start of treatment than women who would remain untreated.ConclusionWomen who would subsequently use hormone replacement therapy were already at lower cardiovascular risk before the start of treatment than women who would remain untreated. Some of the claimed beneficial effects of treatment may thus be explained by women who would use hormone replacement therapy representing a healthier cohort than women who would remain untreated.

Key messages

• Many retrospective epidemiological studies have shown that hormone replacement therapy reduces the risk of cardiovascular disease
• Results from the prospective population study in Gothenburg show that there were already differences in risk factor profile of women before hormone replacement therapy was considered
• It is too early to recommend hormone replacement therapy for prevention of cardiovascular disease before controlled randomised studies have been performed