BACKGROUND: Allogeneic red blood cell transfusion is frequently used in total hip replacement surgery (THR). However, data on the prognosis of transfused patients are sparse. In this study we compared the risk of complications following THR in transfused and non-transfused patients. METHODS: A population-based follow-up study was performed using data from medical databases in Denmark. We identified 28,087 primary THR procedures performed from 1999 to 2007, from which we computed a propensity score for red blood cell transfusion based on detailed data on patient-, procedure-, and hospital-related characteristics. We were able to match 2,254 transfused with 2,254 non-transfused THR patients using the propensity score. RESULTS: Of the 28,087 THR patients, 9,063 (32.3%) received at least one red blood cell transfusion within 8 days of surgery. Transfused patients had higher 90-day mortality compared with matched non-transfused patients: the adjusted OR was 2.2 (95% confidence interval (CI): 1.2-3.8). Blood transfusion was also associated with increased odds of pneumonia (OR 2.1; CI: 1.2-3.8), whereas the associations with cardiovascular or cerebrovascular events (OR 1.4; CI: 0.9-2.2) and venous thromboembolism (OR 1.2; CI: 0.7-2.1) did not reach statistical significance. The adjusted OR of reoperation due to infection was 0.6 (CI: 0.1-2.9). CONCLUSIONS: Red blood cell transfusion was associated with an adverse prognosis following primary THR, in particular with increased odds of death and pneumonia. Although the odds estimates may partly reflect unmeasured bias due to blood loss, they indicate the need for careful assessment of the risk versus benefit of transfusion even in relation to routine THR procedures.
There is increasing evidence that inflammation plays an important role in atherosclerosis. Such inflammation is likely related to the presence of infectious organisms. Hence, we examined whether the use of antibiotic drugs decreases the risk of first-time myocardial infarction (MI). We identified 6737 cases of first-time hospitalization for MI, and 67,364 age- and gender-matched, population-based controls during 1991-2002, using data from the County Hospital Discharge Registry and the Civil Registration System of North Jutland County, Denmark. All prescriptions for antibiotics prior to the hospitalization for MI were identified through a prescription database. Conditional logistic regression was used to estimate odds ratios (OR) associated with antibiotic use, adjusted for potential confounding factors including previous discharge diagnoses of hypertension, chronic bronchitis and emphysema, alcoholism, liver cirrhosis, or diabetes mellitus and prescriptions for anti-hypertensive drugs, antidiabetic drugs, lipid-lowering agents, high-dose aspirin, platelet inhibitors, oral anticoagulants, or hormone replacement therapy. The use of any one type of antibiotic in the 3 years before hospitalization was not associated with a decreased risk of MI; the adjusted ORs with corresponding 95% confidence intervals were 1.07, 1.00-1.14 for penicillins; 1.15, 1.00-1.33 for macrolides; 0.95, 0.65-1.39 for tetracyclines; 1.25, 0.84-1.87 for quinolones; and 0.95, 0.80-1.12 for sulfonamides. A slight increase in the risk of MI was seen with the use of more than one type of antibiotic in the preceding 3 years (OR = 1.17, 95% CI = 1.09-1.27). Our findings do not support the hypothesis that the use of antibiotics is associated with a lower risk of first-time MI.
PURPOSE: Several studies have found an increased risk of myocardial infarction among depressed patients. Selective serotonin reuptake inhibitors (SSRIs) appear to lack the arrhythmic adverse effects of tricyclic antidepressants, and are thought to inhibit platelet aggregation. We examined whether use of different antidepressant classes is associated with a lower risk of first-time hospitalization for myocardial infarction, as compared with nonuse. METHODS: We identified 8887 cases of first-time hospitalization for myocardial infarction and 88,862 age- and sex-matched population-based controls during 1994-2002, using data from North Jutland County, Denmark. Cases and controls were stratified according to history of cardiovascular disease. All prescriptions for antidepressants before hospitalization for myocardial infarction were identified using a prescription database. Conditional logistic regression was used to estimate odds ratios of myocardial infarction associated with antidepressant use, adjusted for possible confounding factors. RESULTS: In patients with a history of cardiovascular disease, we found indications of a lower risk of myocardial infarction among those who used SSRIs (adjusted odds ratio [OR] = 0.85; 95% confidence interval [CI]: 0.62 to 1.16), nonselective serotonin reuptake inhibitors (adjusted OR = 0.83; 95% CI: 0.50 to 1.38), and other antidepressants (adjusted OR = 0.55; 95% CI: 0.31 to 0.97). There were no such associations among persons without a history of cardiovascular disease. CONCLUSION: Antidepressant use may be associated with a decreased risk of hospitalization for myocardial infarction among persons with a history of cardiovascular disease, although it remains uncertain whether there are differences by class of antidepressant.
Both asthma and abdominal aortic aneurysms (AAA) involve inflammation. It remains unknown whether these diseases interact.
Databases analyzed included Danish National Registry of Patients, a population-based nationwide case-control study included all patients with ruptured AAA and age- and sex-matched AAA controls without rupture in Denmark from 1996 to 2012; Viborg vascular trial, subgroup study of participants from the population-based randomized Viborg vascular screening trial. Patients with asthma were categorized by hospital diagnosis, bronchodilator use, and the recorded use of other anti-asthma prescription medications. Logistic regression models were fitted to determine whether asthma associated with the risk of ruptured AAA in Danish National Registry of Patients and an independent risk of having an AAA at screening in the Viborg vascular trial. From the Danish National Registry of Patients study, asthma diagnosed
We aimed to assess cancer risk in congenital heart defect patients, with and without Down's syndrome, compared with the general population.
We identified all patients born and diagnosed with congenital heart defects from 1977 to 2008 using the Danish National Registry of Patients, covering all Danish hospitals. We compared cancer incidence in the congenital heart defect cohort with that expected in the general population (~5.5 million) using the Danish Cancer Registry, and computed age- and gender-standardised incidence ratios.
We identified 15,905 congenital heart defect patients, contributing a total of 151,172 person-years at risk; the maximum length of follow-up was 31 years (median 8 years). In all, 53 patients were diagnosed with cancer, including 30 female and 23 male patients (standardised incidence ratio = 1.63; 95% confidence interval: 1.22-2.13). Risks were increased for leukaemia, brain tumours, and basal cell carcinoma. After excluding 801 patients with Down's syndrome, the standardised incidence ratio was 1.19 (95% confidence interval: 0.84-1.64). In the subgroup of 5660 non-Down's syndrome patients undergoing cardiac surgery or catheter-based interventions, the standardised incidence ratio was 1.45 (95% confidence interval: 0.86-2.29).
The overall risk of cancer among congenital heart defect patients without Down's syndrome was not statistically significantly elevated. Cancer risk in the congenital heart defect cohort as a whole, including patients with Down's syndrome, was increased compared with the general population, although the absolute risk was low. Studies with longer follow-up and more information on radiation doses are needed to further examine a potential cancer risk associated with diagnostic radiation exposure.
The aim of the current study was to present and discuss a broad range of register-based definitions of chronic conditions for use in register research, as well as the challenges and pitfalls when defining chronic conditions by the use of registers.
The definitions were defined based on information from nationwide Danish public healthcare registers. Medical and epidemiological specialists identified and grouped relevant diagnosis codes that covered chronic conditions, using the International Classification System version 10 (ICD-10). Where relevant, prescription and other healthcare data were also used to define the chronic conditions.
We identified 199 chronic conditions and subgroups, which were divided into four groups according to a medical judgment of the expected duration of the conditions, as follows. Category I: Stationary to progressive conditions (maximum register inclusion time of diagnosis since the start of the register in 1994). Category II: Stationary to diminishing conditions (10 years of register inclusion after time of diagnosis). Category III: Diminishing conditions (5 years of register inclusion after time of diagnosis). Category IV: Borderline conditions (2 years of register inclusion time following diagnosis). The conditions were primarily defined using hospital discharge diagnoses; however, for 35 conditions, including common conditions such as diabetes, chronic obstructive lung disease and allergy, more complex definitions were proposed based on record linkage between multiple registers, including registers of prescribed drugs and use of general practitioners' services. CONCLUSIONS THIS STUDY PROVIDED A CATALOG OF REGISTER-BASED DEFINITIONS FOR CHRONIC CONDITIONS FOR USE IN HEALTHCARE PLANNING AND RESEARCH, WHICH IS, TO THE AUTHORS' KNOWLEDGE, THE LARGEST CURRENTLY COMPILED IN A SINGLE STUDY.
Chlamydia pneumoniae has been linked with increased risk of cardiovascular disease, but data on stroke are sparse. We examined whether seropositivity to Chlamydia pneumoniae was associated with the risk of ischemic stroke in a nested case-control study. Data on Chlamydia pneumoniae serology, lifestyle factors, and medical history were obtained at baseline. Verified cases (n = 254) were compared with gender- and age-matched controls (n = 254). Positive IgA (> or = 1:16) or IgG (> or = 1:64) titers were associated with an increased risk of acute ischemic stroke, i.e. adjusted odds ratios (ORs) were 1.54 (95% confidence interval, CI: 0.96-2.47) and 1.28 (95% CI: 0.83-1.95). The adjusted OR was 1.77 (95% CI: 1.04-3.00) when both titers were elevated. The highest point estimates were seen for ischemic stroke due to large-artery atherosclerosis, adjusted OR: 6.32 (95% CI: 0.76-52.61) (IgG (> or = 1:64)). No clear associations were found for other types of ischemic stroke. The strength of the association varied depending on gender and the chosen cut-off values for the antibody titers. These results partly support the hypothesis that serologic evidence of Chlamydia pneumoniae infection may be associated with an increased risk of ischemic stroke. However, the risk may differ according to gender, subtype of ischemic stroke, and cut-off value of antibody titers.
The efficacy of primary percutaneous coronary intervention (PPCI) has been documented in several randomized-controlled trials. We sought to examine the clinical outcome after PPCI of real-world patients eligible and ineligible for inclusion in a randomized trial (DANAMI-2) and to compare it to the outcome of the DANAMI-2 population. We did a population-based follow-up study comparing 1,320 consecutive real-world patients treated with PPCI from 2004 to 2006 to 686 patients treated with PPCI in the DANAMI-2 trial. By reviewing medical records we determined whether the real-world patients were eligible in the DANAMI-2 trial. The real-world population had a more adverse baseline risk profile. Cumulative incidences of the composite end point of all-cause mortality, reinfarction, and stroke after 1 year and 2 years were 17.8% and 22.0%, respectively, in the real-world population compared to 13.6% and 17.3% in the DANAMI-2 population. After adjustment for differences in baseline characteristics and treatment, differences persisted after 1 year (adjusted hazard ratio 1.8, 95% confidence interval 1.3 to 2.6) and 2 years (adjusted hazard ratio 1.7, 95% confidence interval 1.2 to 2.3). Results for the real-world patients eligible according to DANAMI-2 criteria were comparable to the results from the DANAMI-2 trial. In conclusion, real-world patients had a more adverse baseline prognostic profile and a poorer clinical outcome compared to the DANAMI-2 patients. However, clinical outcome in the real-world patients eligible in the DANAMI-2 trial was comparable to that for the DANAMI-2 patients after invasive and medical treatment.
The beneficial effects of smoking cessation on the progression of COPD are well established. Nevertheless, many patients with COPD continue to smoke.
In this nationwide hospital-based prospective follow-up study, we examined rates of smoking cessation and clinical and sociodemographic determinants of smoking cessation in 3,233 patients with COPD who smoked on outpatient contact during 2008 to 2012. Using multivariate Cox regression, we calculated hazard ratios (HRs) of quitting.
Within 1 and 5 years from first outpatient contact, the probability of quitting was 19%?and 45%, respectively. In adjusted analyses, patients were less likely to quit if they were younger, with an HR of 0.84 (95%?CI, 0.71-0.99) for patients aged 50 to 69 years and 0.53 (95%?CI, 0.37-0.76) for patients aged 30 to 49, compared with those aged 70 years or older, who had lower income (HR, 0.79; 95%?CI, 0.67-0.94), lived alone (HR, 0.75; 95%?CI, 0.64-0.88), were unemployed (HR, 0.70; 95%?CI, 0.54-0.90), had milder COPD with an HR of?0.67 (95%?CI, 0.53-0.84) for Global Initiative for Chronic Obstructive Lung Disease (GOLD) A and 0.61 (95%?CI, 0.47-0.80) for GOLD B compared with GOLD D, had Medical Research Council (MRC) dyspnea scale score?
OBJECTIVE: Patients with diabetes may carry a higher case fatality of invasive pneumococcal infection compared with nondiabetic patients due to decreased immunity, risk of metabolic derangement, or angiopathy. We conducted a population-based cohort study to assess the impact of diabetes on mortality within 90 days in patients with pneumococcal bacteremia. RESEARCH DESIGN AND METHODS: All patients with community-acquired pneumococcal bacteremia in North Jutland County, Denmark, from January 1992 to December 2001 were retrieved from the County Bacteremia Registry. Using civil registry numbers, patients with diabetes were identified by record linkage with the County Prescription Database (for antidiabetic drugs) and the County Hospital Discharge Registry. Mortality within 90 days was determined through the Central Population Registry. Mortality rates were compared for diabetic and nondiabetic patients and adjusted for sex, age, and comorbidity. RESULTS: Among 628 patients aged >15 years with community-acquired pneumococcal bacteremia, 63 (10.0%) had diabetes. The diabetic patients were slightly older (median age 71.7 years) than the nondiabetic patients (67.0 years), and the proportion of patients with comorbidity was higher in the diabetic group (59 vs. 46%). Mortality in diabetic patients compared with nondiabetic patients was 11.1 vs. 16.5% after 30 days and 16.0 vs. 19.5% after 90 days, respectively. After adjustment for sex, age, and comorbidity, the mortality rate ratio for diabetic patients was 0.6 (95% CI 0.3-1.2) compared with the nondiabetic patients. CONCLUSIONS: Diabetic patients with community-acquired pneumococcal bacteremia appear not to have a higher case fatality than nondiabetic patients.