Temperature, plant species and residence time effects on nitrogen removal in model treatment wetlands.

Total nitrogen (TN) removal in treatment wetlands (TWs) is challenging due to nitrogen cycle complexity and the variation of influent nitrogen species. Plant species, season, temperature and hydraulic loading most likely influence root zone oxygenation and appurtenant nitrogen removal, especially for ammonium-rich wastewater. Nitrogen data were collected from two experiments utilizing batch-loaded (3-, 6-, 9- and 20-day residence times), sub-surface TWs monitored for at least one year during which temperature was varied between 4 and 24 °C. Synthetic wastewater containing 17 mg/l N as NH4 and 27 mg/l amino-N, 450 mg/l chemical oxygen demand (COD), and 13 mg/l SO4-S was applied to four replicates of Carex utriculata, Schoenoplectus acutus and Typha latifolia and unplanted controls. Plant presence and species had a greater effect on TN removal than temperature or residence time. Planted columns achieved approximately twice the nitrogen removal of unplanted controls (40-95% versus 20-50% removal) regardless of season and temperature. TWs planted with Carex outperformed both Typha and Schoenoplectus and demonstrated less temperature dependency. TN removal with Carex was excellent at all temperatures and residence times; Schoenoplectus and Typha TN removal improved at longer residence times. Reductions in TN were not accompanied by increases in NO3, which was consistently below 1 mg/l N.

Randomized clinical trial of enhanced recovery versus standard care after laparoscopic sleeve gastrectomy.

BACKGROUND: Optimized perioperative care within an enhanced recovery after surgery (ERAS) protocol is designed to reduce morbidity after surgery, resulting in a shorter hospital stay. The present study evaluated this approach in the context of sleeve gastrectomy for patients with morbid obesity. METHODS: Patients were allocated to perioperative care according to a bariatric ERAS protocol or a control group that received standard care. These groups were also compared with a historical group of patients who underwent laparoscopic sleeve gastrectomy at the same institution between 2006 and 2010, selected using matched propensity scores. The primary outcome was median length of hospital stay. Secondary outcomes included readmission rates, postoperative morbidity, postoperative fatigue and mean cost per patient. RESULTS: Of 116 patients included in the analysis, 78 were allocated to the ERAS (40) or control (38) group and there were 38 in the historical group. There were no differences in baseline characteristics between groups. Median hospital stay was significantly shorter in the ERAS group (1 day) than in the control (2 days; P < 0·001) and historical (3 days; P < 0·001) groups. It was also shorter in the control group than in the historical group (P = 0·010). There was no difference in readmission rates, postoperative complications or postoperative fatigue. The mean cost per patient was significantly higher in the historical group than in the ERAS (P = 0·010) and control (P = 0·018) groups. CONCLUSION: The ERAS protocol in the setting of bariatric surgery shortened hospital stay and was cost-effective. There was no increase in perioperative morbidity. REGISTRATION NUMBER: NCT01303809 (http://www.clinicaltrials.gov).

The natural history of eczema from birth to adult life: a cohort study.

BACKGROUND: Eczema is common in infancy; however, there is little evidence about its natural history to adulthood. OBJECTIVES: To study the natural history of eczema from birth to young adult life with particular reference to its relation to atopy. METHODS: A birth cohort of children with atopic family histories was followed for 23 years. Clinical examinations were conducted until the age of 7 years, skin-prick tests and serum total IgE were recorded in infancy and at ages 7 and 23 years, and questionnaires about eczema symptoms were completed at 15 and 23 years. RESULTS: Information was obtained on 497 subjects at birth, 482 at 1 year, 440 at 7 years, 363 at 15 years and 304 at 23 years. Eczema usually remitted from age 1 to 7 years but became more persistent from the age of 15 years, especially in those who were atopic. The prevalence of eczema rose in women from age 15 to 23 years but declined in men. Adults with eczema had higher IgE than those without at 3 months (geometric mean 3·0 vs. 1·7 kU L(-1); P=0·01), 7 years (107·9 vs. 45·2 kU L(-1); P=0·01) and 23 years (123·4 vs. 42·3 kU L(-1); P=0·01), and were more likely to have had positive skin-prick tests at 1 year of age. Current eczema was associated with raised IgE in infancy and adulthood but not in childhood. CONCLUSIONS: Predisposed infants and children with eczema usually grow out of the disease, but in adolescence it is more likely to persist. Adult eczema is related to atopy from the age of 3 months.

Floating treatment wetlands for domestic wastewater treatment.

Floating islands are a form of treatment wetland characterized by a mat of synthetic matrix at the water surface into which macrophytes can be planted and through which water passes. We evaluated two matrix materials for treating domestic wastewater, recycled plastic and recycled carpet fibers, for chemical oxygen demand (COD) and nitrogen removal. These materials were compared to pea gravel or open water (control). Experiments were conducted in laboratory scale columns fed with synthetic wastewater containing COD, organic and inorganic nitrogen, and mineral salts. Columns were unplanted, naturally inoculated, and operated in batch mode with continuous recirculation and aeration. COD was efficiently removed in all systems examined (>90% removal). Ammonia was efficiently removed by nitrification. Removal of total dissolved N was ∼50% by day 28, by which time most remaining nitrogen was present as NO(3)-N. Complete removal of NO(3)-N by denitrification was accomplished by dosing columns with molasses. Microbial communities of interest were visualized with denaturing gradient gel electrophoresis (DGGE) by targeting specific functional genes. Shifts in the denitrifying community were observed post-molasses addition, when nitrate levels decreased. The conditioning time for reliable nitrification was determined to be approximately three months. These results suggest that floating treatment wetlands are a viable alternative for domestic wastewater treatment.

Investigation of classical epidemiological links between patients harbouring identical, non-predominant meticillin-resistant Staphylococcus aureus genotypes and lessons for epidemiological tracking.

According to molecular epidemiology theory, two isolates belong to the same chain of transmission if they are similar according to a highly discriminatory molecular typing method. This has been demonstrated in outbreaks, but is rarely studied in endemic situations. Person-to-person transmission cannot be established when isolates of meticillin-resistant Staphylococcus aureus (MRSA) belong to endemically predominant genotypes. By contrast, isolates of infrequent genotypes might be more suitable for epidemiological tracking. The objective of the present study was to determine, in newly identified patients harbouring non-predominant MRSA genotypes, whether putative epidemiological links inferred from molecular typing could replace classical epidemiology in the context of a regional surveillance programme. MRSA genotypes were defined using double-locus sequence typing (DLST) combining clfB and spa genes. A total of 1,268 non-repetitive MRSA isolates recovered between 2005 and 2006 in Western Switzerland were typed: 897 isolates (71%) belonged to four predominant genotypes, 231 (18%) to 55 non-predominant genotypes, and 140 (11%) were unique. Obvious epidemiological links were found in only 106/231 (46%) patients carrying isolates with non-predominant genotypes suggesting that molecular surveillance identified twice as many clusters as those that may have been suspected with classical epidemiological links. However, not all of these molecular clusters represented person-to-person transmission. Thus, molecular typing cannot replace classical epidemiology but is complementary. A prospective surveillance of MRSA genotypes could help to target epidemiological tracking in order to recognise new risk factors in hospital and community settings, or emergence of new epidemic clones.

Effects on patients with asthma of eradicating visible indoor mould: a randomised controlled trial.

BACKGROUND: It is not clear whether associations between respiratory symptoms and indoor mould are causal. A randomised controlled trial was conducted to see whether asthma improves when indoor mould is removed. METHODS: Houses of patients with asthma were randomly allocated into two groups. In one group, indoor mould was removed, fungicide was applied and a fan was installed in the loft. In the control group, intervention was delayed for 12 months. Questionnaires were administered and peak expiratory flow rate was measured at baseline, 6 months and 12 months. RESULTS: Eighty-one houses were allocated to the intervention group and 83 to the control group; 95 participants in 68 intervention houses and 87 in 63 control houses supplied follow-up information. Peak expiratory flow rate variability declined in both groups, with no significant differences between them. At 6 months, significantly more of the intervention group showed a net improvement in wheeze affecting activities (difference between groups 25%, 95% CI 3% to 47%; p = 0.028), perceived improvement of breathing (52%, 95% CI 30% to 74%; p<0.0001) and perceived reduction in medication (59%, 95% CI 35% to 81%; p<0.0001). By 12 months the intervention group showed significantly greater reductions than the controls in preventer and reliever use, and more improvement in rhinitis (24%, 95% CI 9% to 39%; p = 0.001) and rhinoconjunctivitis (20%, 95% CI 5% to 36%; p = 0.009). CONCLUSIONS: Although there was no objective evidence of benefit, symptoms of asthma and rhinitis improved and medication use declined following removal of indoor mould. It is unlikely that this was entirely a placebo effect.

The effects of dietary advice and vouchers on the intake of fruit and fruit juice by pregnant women in a deprived area: a controlled trial.

OBJECTIVE: To examine the effectiveness of two methods of increasing fruit and fruit juice intake in pregnancy: midwives' advice and vouchers exchangeable for juice. DESIGN: Pregnant women were randomly allocated to three groups: a control group, who received usual care; an advice group, given advice and leaflets promoting fruit and fruit juice consumption; and a voucher group, given vouchers exchangeable for fruit juice from a milk delivery firm. Dietary questionnaires were administered at ~16, 20 and 32 weeks of pregnancy. Serum beta-carotene was measured at 16 and 32 weeks. SETTING: An antenatal clinic in a deprived area. SUBJECTS: Pregnant women aged 17 years and over. RESULTS: The study comprised 190 women. Frequency of fruit consumption declined during pregnancy in all groups, but that of fruit juice increased substantially in the voucher group. Serum beta-carotene concentration increased in the voucher group, from 106.2 to 141.8 micromol l(-1) in women with measurements on both occasions (P = 0.003), decreased from 120.0 to 99.8 micromol l(-1) in the control group (P = 0.005), and was unchanged in the advice group. CONCLUSIONS: Pregnant women drink more fruit juice if they receive vouchers exchangeable for juice supplied by the milk delivery service. Midwives' advice to eat more fruit has no great effect. Providing vouchers for fruit juice is a simple method of increasing its intake in a deprived population and may be useful for other sections of the community.

Denaturing gradient gel electrophoresis can rapidly display the bacterial diversity contained in 16S rDNA clone libraries.

Two different strategies for molecular analysis of bacterial diversity, 16S rDNA cloning and denaturing gradient gel electrophoresis (DGGE), were combined into a single protocol that took advantage of the best attributes of each: the ability of cloning to package DNA sequence information and the ability of DGGE to display a community profile. In this combined protocol, polymerase chain reaction products from environmental DNA were cloned, and then DGGE was used to screen the clone libraries. Both individual clones and pools of randomly selected clones were analyzed by DGGE, and these migration patterns were compared to the conventional DGGE profile produced directly from environmental DNA. For two simple bacterial communities (biofilm from a humics-fed laboratory reactor and planktonic bacteria filtered from an urban freshwater pond), pools of 35-50 clones produced DGGE profiles that contained most of the bands visible in the conventional DGGE profiles, indicating that the clone pools were adequate for identifying the dominant genotypes. However, DGGE profiles of two different pools of 50 clones from a lawn soil clone library were distinctly different from each other and from the conventional DGGE profile, indicating that this small number of clones poorly represented the bacterial diversity in soil. Individual clones with the same apparent DGGE mobility as prominent bands in the humics reactor community profiles were sequenced from the clone plasmid DNA rather than from bands excised from the gel. Because a longer fragment was cloned (approximately 1500 bp) than was actually analyzed in DGGE (approximately 350 bp), far more sequence information was available using this approach that could have been recovered from an excised gel band. This clone/DGGE protocol permitted rapid analysis of the microbial diversity in the two moderately complex systems, but was limited in its ability to represent the diversity in the soil microbial community. Nonetheless, clone/DGGE is a promising strategy for fractionating diverse microbial communities into manageable subsets consisting of small pools of clones.

Asthma prevalence in 1973, 1988 and 2003.

BACKGROUND: A study was undertaken to see whether the prevalence of asthma has changed since a survey was conducted in 1988, using the same methods that showed an increase during the previous 15 years. METHODS: A survey of 12 year old children was conducted in schools in South Wales where surveys had taken place in 1973 and 1988. The survey comprised a parentally completed questionnaire and an exercise challenge test, performed when no bronchodilator had been recently used. RESULTS: In 1973, 1988, and 2003, questionnaires were obtained for 817, 965 and 1148 children, respectively; the exercise test was performed by 812, 960 and 1019 children, respectively. The prevalence of reported wheeze in the last year rose during each 15 year period (9.8%, 15.2%, 19.7%), with an even steeper rise in reported asthma ever (5.5%, 12.0%, 27.3%). There was a continued increase in wheeze attributed to running, in terms of all children (5.8%, 10.5%, 16.0%) and also as the proportion of those with a history of wheeze (34.1%, 47.0%, 57.3%). The use of inhaled corticosteroids (not available in 1973) increased fourfold between 1988 and 2003. The prevalence of exercise induced bronchoconstriction rose between 1973 and 1988 but had declined by 2003. CONCLUSIONS: The rise in the prevalence of asthmatic symptoms has continued since 1988. This appears to conflict with a reported recent decline, unless asthma prevalence peaked in the 1990s. The decline in exercise induced bronchoconstriction is probably attributable to better control of the disease as more children are now using inhaled corticosteroids as preventive treatment.

Is fish oil good or bad for heart disease? Two trials with apparently conflicting results.

Two successive randomized trials examined the effect of an increased intake of fatty fish, or the use of fish oil supplements, in reducing mortality in men with heart disease. The Diet and Reinfarction Trial (DART) was conducted in 2033 men who were recovering from acute myocardial infarction (MI). Those who were advised to eat fatty fish (or who opted to take fish oil capsules instead) had a 29% reduction in all-cause mortality over the following two years compared with those not so advised. The effect appeared in the first few months of the trial. The Diet and Angina Randomized Trial (DART 2) involved 3114 men with stable angina. Advice to eat fatty fish did not reduce mortality, and taking fish oil capsules was associated with a higher risk of cardiac and sudden death. The adverse effects of fish or fish oil were restricted to men not taking beta-blockers or dihydropyridine calcium-channel blockers, and were greater in those taking digoxin. Evidence from other sources strongly suggests an anti-arrhythmic action of fish oil, particularly after MI or in the presence of acute ischemia. The apparently conflicting results of the two trials may reflect different actions of n-3 fatty acids in acute and chronic conditions, together with different effects of eating fish and taking fish oil capsules. A mechanism is proposed that could account for these findings.

House dust mite control measures for asthma.

BACKGROUND: The major allergen in house dust comes from mites. Chemical, physical and combined methods of reducing mite allergen levels are intended to reduce asthma symptoms in people who are sensitive to house dust mites. OBJECTIVES: To assess the effects of reducing exposure to house dust mite antigens in the homes of people with mite-sensitive asthma. SEARCH STRATEGY: Cochrane Airways Group trials register, and PubMed and The Cochrane Library (last searches June 2004), reference lists. SELECTION CRITERIA: Randomised trials of mite control measures vs placebo or no treatment in asthmatic people known to be sensitive to house dust mites. DATA COLLECTION AND ANALYSIS: Two reviewers applied the trial inclusion criteria, assessed their quality and extracted the data independently. Study authors were contacted to clarify information. MAIN RESULTS: Forty-nine trials (2733 patients) were included; the number of patients has more than doubled since the last version of this review. Thirty-one trials assessed physical methods, ten assessed chemical methods, and eight a combination of chemical and physical methods. Despite the fact that many trials were of poor quality and would be expected to exaggerate the reported effect, we did not find an effect of the interventions. For the most frequently reported outcome, peak flow in the morning (1339 patients), the standardised mean difference was -0.02 (95% confidence interval (CI) -0.13 to 0.08). There were no statistically significant differences either in number of patients improved (relative risk 1.01, 95% CI 0.80 to 1.27), asthma symptom scores (standardised mean difference -0.01, 95% CI -0.10 to 0.13), or in medication usage (standardised mean difference -0.05, 95% CI -0.18 to 0.09). REVIEWERS' CONCLUSIONS: Chemical and physical methods aimed at reducing exposure to house dust mite allergens cannot be recommended. It is doubtful whether further studies, similar to the ones in our meta-analysis, are worthwhile. If other types of studies are considered, they should be methodologically rigorous and use other methods than those used so far, with careful monitoring of mite exposure and relevant clinical outcomes.

Factors influencing atopic dermatitis-a questionnaire survey of schoolchildren's perceptions.

BACKGROUND: Although there is growing knowledge about factors that may predispose to the onset of atopic dermatitis (AD), little is known about factors which may exacerbate existing disease. AD sufferers and those involved in the management of the disease are often aware of factors that influence its course and severity. However, there is little available evidence on the distribution and relative importance of such factors, and what information exists is derived from selected groups such as hospital patients and may not therefore be representative of the AD population as a whole. OBJECTIVES: To determine the distribution and relative importance of 19 potential exacerbating and relieving factors as perceived by a population-based sample of schoolchildren with AD. METHODS: A questionnaire was used to identify all children with AD in years 8 and 9 (12-14-year-olds) from eight comprehensive schools across Wales. These individuals were then requested to complete a supplementary questionnaire which asked them to state for each of 19 factors whether (i) it makes their eczema better, (ii) it makes their eczema worse, (iii) it has no effect, or (iv) they do not know its effects. RESULTS: Almost 10% (250 of 2501) of children surveyed were considered to have AD, and 90% (225 of 250) of these completed the supplementary questionnaire. Most AD sufferers found that none to two factors relieve their symptoms whilst none to five factors exacerbate them. Sweating from exercise, fabrics (especially wool) and hot weather were the three most common exacerbators, affecting 41.8%, 40% and 39.1%, respectively, of AD responders. The three key relievers were steroid creams (22.2% of AD responders), moisturizers/makeup (16.4%) and medicines/tablets (13.8%). Almost 60% of respondents believed foods have no effect on their symptoms. There was also evidence to suggest that 12.4% (28 of 225) of participants may use creams which they are not aware contain steroids. CONCLUSIONS: These findings shed light on the relative perceived importance of factors such as food, aeroallergens, sweat, climate, illness, stress and therapies for the course of AD in a representative population sample of AD sufferers. Such information might be explored during clinical consultations given the increasing participation of sufferers and their carers in the management of this chronic disease. These findings also form the basis of hypothesis generation for future analytical studies.

The long-term effect of dietary advice on the diet of men with angina: the diet and angina randomized trial.

INTRODUCTION: The long-term effects on diet of dietary advice to eat fruit and vegetables or fatty fish are not well described. MATERIALS AND METHODS: From 1990 to 1996 3114 men aged 37-70 with treated angina were recruited from general practices in South Wales. A dietitian randomly allocated the eligible men to receive advice to eat more fruit and vegetables, or advice to eat more fatty fish, or both these types of advice or neither. In 2000, a brief self-completion questionnaire was sent to a sample of 1191 of the men known to be alive at the end of March 1999. RESULTS: The questionnaire was returned by 944 of the 1036 men alive at the time the questionnaire was sent. Those given fish advice were consuming more fatty fish but the difference was modest 21.9 g day(-1) vs. 14.0 g day(-1) (P < 0.01). The differences in fruit and vegetables intake between those given fruit advice and those not given fruit advice were small 373.2 g day(-1) vs. 351.7 g day(-1) (P = 0.05). DISCUSSION: Men of this age group may be particularly resistant to fruit and vegetables advice; population-based interventions or interventions targeted at women might be more effective.

Effects on respiratory health of a reduction in air pollution from vehicle exhaust emissions.

AIMS: To determine whether residents of congested streets have a higher prevalence of respiratory symptoms than residents of nearby uncongested streets, and whether their respiratory health improves following a reduction in exposure to traffic related air pollutants. METHODS: An area was identified where certain streets were subject to air pollution from heavy road traffic, which was likely to improve following the construction of a by-pass. A respiratory survey was conducted among the residents, together with the residents of nearby uncongested streets, at baseline and again a year after the by-pass opened. Measurements were made of air pollutant concentrations in both areas on both occasions. RESULTS: Initial concentrations of PM10 and PM2.5 were substantially higher in the congested than in the uncongested streets. When the by-pass opened, the volume of heavy goods traffic fell by nearly 50%. PM10 decreased by 23% (8.0 microg/m3) in the congested streets and by 29% (3.4 microg/m3) in the uncongested streets, with similar proportionate falls in PM2.5. There were no clear or consistent differences between the residents of the two areas initially in terms of symptoms or peak flow variability. Repeat questionnaires were obtained from 165 and 283 subjects in the congested and uncongested areas respectively, and showed a tendency for most symptoms to improve in both areas. For chest symptoms, the improvement tended to be greater in the uncongested area, although the difference between the areas was not statistically significant. Rhinitis and rhinoconjunctivitis tended to improve to a greater extent in the congested streets; the difference between the areas was significant for the degree to which rhinitis interfered with daily activities. Peak flow variability tended to improve in the uncongested area. CONCLUSIONS: The by-pass reduced pollutant levels to a degree that probably alleviates rhinitis and rhinoconjunctivitis but has little effect on lower respiratory symptoms.

Pollen counts in relation to the prevalence of allergic rhinoconjunctivitis, asthma and atopic eczema in the International Study of Asthma and Allergies in Childhood (ISAAC).

BACKGROUND: Although pollens are major allergens associated with allergic rhinoconjunctivitis and asthma, there is little information about the relative prevalence of these conditions in populations with different pollen exposures. OBJECTIVE: The purpose of this study was to investigate the relationship between pollen exposure and allergic symptoms among children in different countries. METHODS: An ecological analysis was conducted to see whether pollen exposure (pollen counts, and duration and severity of pollen seasons) is associated with symptoms of allergic rhinoconjunctivitis, asthma and atopic eczema in 28 centres within 11 countries (nine being in Europe). Data on the prevalence of symptoms in 13-14-year olds were based on the responses to the written questionnaires from the International Study of Asthma and Allergies in Childhood (ISAAC). The analysis was adjusted for gross national product and mean annual relative humidity. RESULTS: There was little relationship between pollen exposure and symptom prevalence, except for a significant inverse association between grass pollen counts and lifetime prevalence of the symptoms of allergic rhinitis (P=0.03). Almost all the regression coefficients were negative. The associations were even weaker and all non-significant when the analyses were conducted within countries, using a random intercept fixed slope model, but there was still no evidence of a positive association between pollen exposure and symptoms. CONCLUSION: There is a weak but consistent tendency for the prevalence of allergic symptoms to be inversely associated with pollen exposure. This finding accords with evidence from several countries, suggesting that the prevalence of hayfever and asthma tends to be lower in rural than in urban areas, and lowest among people living on farms. Exposure to allergenic pollen in early life does not appear to increase the risk of acquiring symptoms of respiratory allergy, and may even give some protection against them.

A comparison of the effect of advice to eat either '5-a-day' fruit and vegetables or folic acid-fortified foods on plasma folate and homocysteine.

OBJECTIVE: To assess and compare the effects of natural folate (100 micro g) with those of folic acid from fortified sources (100 micro g/day) on plasma folate and homocysteine. DESIGN: Randomized controlled trial (parallel groups). SETTING: Men and women living in South Wales, UK. SUBJECTS: A total of 135 healthy individuals recruited from the local workforce and blood donor sessions. All subjects possessed the 'wild-type' CC genotype for C677T polymorphism in methylenetetrahydrofolate reductase (MTHFR). INTERVENTIONS: Subjects underwent one of the following dietary interventions for 4 months: (1) fortified diet-usual diet plus 100 microg/day folic acid from fortified foods; (2) natural folate diet-usual diet plus 100 microg/day folate from natural sources; (3) control-usual diet. RESULTS: The fortified group increased reported intake of folic acid from fortified foods compared to other groups (P<0.001) achieving an extra 98 microg/day (95% CI 88-108). The natural folate group increased reported intake of natural source folates compared with the other two groups (P<0.001), but achieved a mean increase of only 50 microg/day (95% CI 34-66). Plasma folate increased (P<0.01) by a similar amount in both intervention groups compared to controls (fortified group 2.97, 95% CI 0.8-5.1; natural group 2.76, 95% CI 0.6-4.9. Plasma homocysteine, vitamins B(6) and B(12) were not significantly changed. CONCLUSIONS: Subjects achieved increases in folate intake using fortified foods more easily than by folate-rich foods, however both sources increased plasma folate by a similar amount. These levels of intake were insufficient to reduce homocysteine concentrations in MTHFR CC homozygotes, but may be more effective in other genotypes.

Lack of benefit of dietary advice to men with angina: results of a controlled trial.

OBJECTIVE: To see whether mortality among men with angina can be reduced by dietary advice. DESIGN: A randomized controlled factorial trial. SETTING: Male patients of general practitioners in south Wales. SUBJECTS: A total of 3114 men under 70 y of age with angina. INTERVENTIONS: Subjects were randomly allocated to four groups: (1) advised to eat two portions of oily fish each week, or to take three fish oil capsules daily; (2) advised to eat more fruit, vegetables and oats; (3) given both the above types of advice; and (4) given no specific dietary advice. Mortality was ascertained after 3-9 y. RESULTS: Compliance was better with the fish advice than with the fruit advice. All-cause mortality was not reduced by either form of advice, and no other effects were attributable to fruit advice. Risk of cardiac death was higher among subjects advised to take oily fish than among those not so advised; the adjusted hazard ratio was 1.26 (95% confidence interval 1.00, 1.58; P=0.047), and even greater for sudden cardiac death (1.54; 95% CI 1.06, 2.23; P=0.025). The excess risk was largely located among the subgroup given fish oil capsules. There was no evidence that it was due to interactions with medication. CONCLUSIONS: Advice to eat more fruit was poorly complied with and had no detectable effect on mortality. Men advised to eat oily fish, and particularly those supplied with fish oil capsules, had a higher risk of cardiac death. This result is unexplained; it may arise from risk compensation or some other effect on patients' or doctors' behaviour.