Berit Jamie Nielsen

Nation-wide Salmonella enterica surveillance and control in Danish slaughter swine herds

A nation-wide Salmonella enterica surveillance and control programme was initiated in Danish finishing herds over the first quarter of 1995. In Denmark, all swine for slaughter are identifiable by a unique herd code. For each herd code, and depending on the herds annual kill, random samples ranging from four to more than 60 swine are obtained quarterly at the abattoir. A meat sample from each pig is frozen, and meat juice (harvested after thawing) is examined for specific antibodies against S. enterica using an indirect enzyme-linked immunosorbent assay (ELISA). The ELISA combines several S. enterica O-antigens, and allows detection of antibody response after a variety of different S. enterica serovar infections. Results are transferred to a central database, which each month (based on meat-juice tests obtained in the previous 13 weeks) assigns all herds into three S. enterica infection levels: Level 1, in which the S. enterica prevalence is deemed low and acceptable; Level 2, where there is a moderate prevalence of S. enterica seroreactors (from > 50% in the smallest to > 10% in the largest herds); Level 3, in which S. enterica seroreactor prevalence is clearly unsatisfactory (> 50% for most herd sizes). Irrespective of Salmonella level, all herds receive a monthly update on the current results of the S. enterica test results. If a herd is categorized in Level 2 or 3, it must receive an advisory visit by a practising veterinarian and a local swine extension specialist, and certain management hygiene precautions must be taken. If a herd is categorized in Level 3, the finishers from the herd must additionally be slaughtered under special hygiene precautions. This is supervised by the veterinary authorities. During 1995, 604000 samples were tested for S. enterica, corresponding to 3.0% of the total kill. In December 1995, 15522 herds (representing > 90% of the national production) were categorized into one of the three levels: 14551 herds (93.7%) in Level 1; 610 herds (3.9%) in Level 2; 361 herds (2.3%) in Level 3. The proportion of serologically positive meat-juice samples collected during 1995 ranged from a mean of 2.9% in smaller herds (101-200 swine slaughtered per year) to 6.1% in relatively large herds (more than 5000 swine slaughtered per year).

Associations of serum potassium levels with mortality in chronic heart failure patients

Aims Medication prescribed to patients suffering from chronic heart failure carries an increased risk of impaired potassium homeostasis. We examined the relation between different levels of serum potassium and mortality among patients with chronic heart failure. Methods and results From Danish National registries, we identified 19 549 patients with a chronic heart failure diagnosis who had a measurement of potassium within minimum 90 days after initiated medical treatment with loop diuretics and angiotensin converting enzyme inhibitors or angiotensin-II receptor blockers. All-cause mortality was examined according to eight predefined potassium levels: 2.8-3.4 mmol/L, 3.5-3.8 mmol/L, 3.9-4.1 mmol/L, 4.2-4.4 mmol/L, 4.5-4.7 mmol/L, 4.8-5.0 mmol/L, 5.1-5.5 mmol/L, and 5.6-7.4 mmol/L. Follow-up was 90 days from potassium measurement. We estimated the risk of all-cause mortality using multivariable adjusted Cox proportional hazard model, with normal serum potassium level at 4.2-4.4 mmol/L as reference. After 90 days, the mortality in the eight strata was 14.4, 8.0, 6.3, 5.0, 5.8, 7.9, 10.3, and 21.1% respectively. In multivariable adjusted analysis, patients with potassium levels of 2.8-3.4 mmol/L [hazard ratio (HR): 3.16; confidence interval (CI): 2.43-4.11], 3.5-3.8 mmol/L (HR: 1.62; CI: 1.31-1.99), 3.9-4.1 mmol/L (HR: 1.29; CI: 1.08-1.55), 4.8-5.0 mmol/L (HR: 1.34; CI: 1.10-1.63), 5.1-5.5 mmol/L (HR: 1.60; CI: 1.29-1.97), and 5.6-7.4 mmol/L (HR: 3.31; CI: 2.61-4.20) had an increased risk of all-cause mortality. Conclusion Levels within the lower and upper levels of the normal serum potassium range (3.5-4.1 mmol/L and 4.8-5.0 mmol/L, respectively) were associated with a significant increased short-term risk of death in chronic heart failure patients. Likewise, potassium below 3.5 mmol/L and above 5.0 mmol/L was also associated with increased mortality.

A population-based study of prognosis in advanced stage follicular lymphoma managed by watch and wait

Watch and wait (WAW) is a common approach for asymptomatic, advanced stage follicular lymphoma (FL), but single‐agent rituximab is an alternative for these patients. In this nationwide study we describe the outcome of patients selected for WAW. A cohort of 286 out of 849 (34%) stage III‐IVA FL patients seen between 2000 and 2011, were managed expectantly and included. The 5‐year progression‐free survival (PFS) was 35% [95% confidence interval (CI) 29–42]. The 10‐year overall survival (OS) was 65% (95%CI 54–78), and the cumulative risk of dying from lymphoma within 10 years of diagnosis was 13% (95%CI 7–20). Elevated lactate dehydrogenase and > four nodal regions involved were associated with a higher risk of lymphoma treatment and death from lymphoma. The WAW patients and a matched background population had similar OS during the first 50 months after diagnosis (P = 0·7), but WAW patients had increased risk of death after 50 months (P < 0·001). The estimated loss of residual life after 10 years was 6·8 months. The 10‐year cumulative risk of histological transformation was 22% (95%CI 15–29) and the 3‐year OS after transformation was 71% (95%CI 58–87%). In conclusion, advanced stage FL managed by WAW had a favourable outcome and abandoning this strategy could lead to overtreatment in some patients.

Leisure-time physical activity and the risk of suspected bacterial infections

INTRODUCTION The risk of upper respiratory tract viral infections is reduced with increased physical activity, but little information is available regarding bacterial infections. We examined the relationship between leisure-time physical activity and suspected bacterial infections. METHODS Information on leisure-time physical activity was obtained from the 2007 and 2010 North Denmark Region Health Surveys of 18,874 Danes and linked to data from nationwide administrative registries. Suspected bacterial infections were determined based on filled prescriptions for antibiotics. Adjusted estimates were calculated using logistic regression models. RESULTS During a 1-yr follow-up, 5368 participants filled at least one antibiotic prescription. There was a statistically significant difference between physical activity level and filling any antibiotic prescriptions among women (P = 0.003) but not among men (P = 0.191). Logistic regression analysis showed that compared with sedentary behavior, all levels of leisure-time physical activities lowered the likelihood of filling an antibiotic prescription. However, after multivariable adjustments, only estimates of low physical activity were significant (odds ratio [OR] = 0.90, 95% confidence interval [CI] = 0.82; 0.99). Multivariable adjusted subgroup analyses of suspected cystitis showed a decreased likelihood of engaging in low (OR = 0.79, 95% CI = 0.65-0.95) and moderate (OR = 0.68, 95% CI = 0.54-0.87) physical activity. CONCLUSION Low leisure-time physical activity is associated with a statistically significant 10% lower risk of suspected bacterial infections during a 1-yr follow-up compared with sedentary behavior. Further, low and moderate levels of physical activity were associated with the statistically significant reduction of suspected cystitis. No reduction in suspected respiratory tract infections was statistically significant and associated with physical activity compared with sedentary behavior.

Alcohol consumption and mortality in patients undergoing coronary artery bypass graft (CABG)-a register-based cohort study

BackgroundPrevious studies have shown that compared with abstinence and heavy drinking, moderate alcohol consumption is associated with a reduced risk of mortality among the general population and patients with heart failure and myocardial infarction. We examined the association between alcohol consumption and mortality in coronary artery bypass graft (CABG) patients.MethodWe studied 1,919 first-time CABG patients using data on alcohol consumption and mortality obtained from Danish national registers from March 2006 to October 2011. Alcohol consumption was divided into the following groups: abstainers (0 units/week), moderate consumers (1–14 units/week), moderate-heavy drinkers (15–21 units/week) and heavy drinkers (>21 units/week). Hazard ratios (HR) of all-cause mortality were calculated using Cox proportional hazard regression analysis.ResultsThe median follow-up was 2.2 years [IQR 2.0]. There were 112 deaths, of which 96 (86 %) were classified as cardiovascular. Adjustments for age and sex showed no increased risk of all-cause mortality for the abstainers (HR 1.61, 95 % CI, 1.00–2.58) and moderate-heavy drinkers (HR 1.40, 95 % CI, 0.73–2.67) compared with moderate consumers. However, heavy drinkers had a high risk of all-cause mortality compared with moderate consumers (HR 2.44, 95 % CI, 1.47–4.04). A full adjustment showed no increase in mortality for the abstainers (HR 1.59, 95 % CI, 0.98–2.57) and moderate-heavy drinkers (HR 1.68, 95 % CI, 0.86–3.29), while heavy drinkers were associated with an increased mortality rate (HR 1.88, 95 % CI, 1.10–3.21). There was no increased risk of 30-day mortality for the abstainers (HR 0.74, 95 % CI, 0.23–2.32), moderate-heavy drinkers (HR 0.36, 95 % CI, 0.07–1.93) and heavy drinkers (HR 2.20, 95 % CI, 0.65–7.36).ConclusionThere was no increased risk of mortality for abstainers (0 units/week) or moderate-heavy drinkers (15–21 units/week) following a CABG. Only heavy drinking (>21 units/week) were significantly associated with an increased mortality rate. These results suggest that only heavy drinking present a risk factor among CABG patients.