Prediction of occult atrial fibrillation in patients after cryptogenic stroke and transient ischaemic attack: PROACTIA.

AIMS: Studies with implantable cardiac monitors (ICMs) show that one-third of patients with cryptogenic stroke/transient ischaemic attack (TIA) have episodes of subclinical atrial fibrillation (SCAF) and benefit switching from antiplatelet- to anticoagulant therapy. However, ICMs are costly and resource demanding. We aimed to build a score based on participant's baseline characteristics that could assess individual risk of SCAF. METHODS AND RESULTS: In a prospective study, 236 eligible patients with a final diagnosis of cryptogenic stroke/TIA had an ICM implantated during the index hospitalization. Pre-specified evaluated variables were: CHA2DS2-VASc, P-wave duration, P-wave morphology, premature atrial beats (PAC)/24 h, supraventricular tachycardia/24 h, left atrial end-systolic volume index (LAVI), Troponin-T, NT-proBNP, and D-dimer. SCAF was detected in 84 patients (36%). All pre-specified variables were significantly associated with SCAF detection in univariate analysis. P-wave duration, followed by PAC/24 h, NT-proBNP, and LAVI, had the largest ratio of SCAF prevalence between its upper and lower quartiles (3.3, vs. 3.2, vs. 3.1 vs. 2.8, respectively). However, in a multivariate analysis, only PAC/24t, P-wave duration, P-wave morphology, and LAVIs remained significant predictors and were included in the PROACTIA score. Subclinical atrial fibrillation prevalence was 75% in the highest vs. 10% in the lowest quartile of the PROACTIA score with a 10-fold higher number of patients with an atrial fibrillation burden >6 h in the highest vs. the lowest quartile. CONCLUSION: The PROACTIA score can identify patients with cryptogenic stroke/TIA at risk of subsequent SCAF detection. The large difference in SCAF prevalence between groups may provide a basis for future tailored therapy. CLINICAL TRIAL REGISTRATION: Clinical Trial Registration: ClinicalTrials.gov; NCT02725944.

Stroke unit demand in Norway - present and future estimates.

BACKGROUND: All stroke patients should receive timely admission to a stroke unit (SU). Consequently, most patients with suspected strokes - including stroke mimics (SM) are admitted. The aim of this study was to estimate the current total demand for SU bed capacity today and give estimates for future (2020-2040) demand. METHODS: Time trend estimates for stroke incidence and time constant estimates for length of stay (LOS) were estimated from the Norwegian Patient Registry (2010-2015). Incidence and LOS models for SMs were based on data from Haukeland University Hospital (2008-2017) and Akershus University Hospital (2020), respectively. The incidence and LOS models were combined with scenarios from Statistic Norway's population predictions to estimate SU demands for each health region. A telephone survey collected data on the number of currently available SU beds. RESULTS: In 2020, 361 SU beds are available, while demand was estimated to 302. The models predict a reduction in stroke incidence, which offsets projected demographic shifts. Still, the estimated demand for 2040 rose to 316, due to an increase in SMs. A variation of this reference scenario, where stroke incidence was frozen at the 2020-level, gave a 2040-demand of 480 beds. CONCLUSIONS: While the stroke incidence is likely to continue to fall, this appears to be balanced by an increase in SMs. An important uncertainty is how long the trend of decreasing stroke incidence can be expected to continue. Since the most important uncertainty factors point toward a potential increase, which may be as large as 50%, we would recommend that the health authorities plan for a potential increase in the demand for SU bed capacity.

Stroke Mimics on the Stroke Unit - Temporal trends 2008-2017 at a large Norwegian university hospital.

OBJECTIVES: The objective was to quantify temporal trends in stroke mimics (SM) admissions relative to cerebrovascular accidents (CVA), incidence of hospitalized SMs and characterize the SM case-mix at a general hospital's stroke unit (SU). MATERIALS & METHODS: All SU admissions (n = 11240) of patients aged 15 or older to Haukeland University Hospital between 2008-2017 were prospectively included and categorized as CVA or SM. Logistic regression was used to estimate time trends in the proportion of SMs among the admissions. Poisson regression was used to estimate time trends in age- and sex-dependent SM incidence. RESULTS: SMs were on average younger thaan CVA patients (68.3 vs. 71.4 years) and had a higher proportion of females (53.6% vs. 44.5%). The total proportion of SM admissions was 51.0%. There was an increasing time trend in the proportion of SM admissions, odds ratio 1.150 per year (p < 0.001), but this trend appears flattening, represented by a significant quadratic time-term, odds ratio 1.009 (p < 0.001). A higher SM proportion was also associated with the time period of a Mass Media Intervention (FAST campaign) in 2014. There was also an increasing trend in SM incidence, that remains after adjusting for age, sex, and population; also, for incidence the trend appears to be flattening. CONCLUSIONS: SMs account for approximately half of the SU admissions, and the proportion has been increasing. A FAST campaign appears to have temporarily increased the SM proportion. The age- and sex-dependent incidence of SM has been increasing but appears to flatten out.

Neural classification of Norwegian radiology reports: using NLP to detect findings in CT-scans of children.

BACKGROUND: With a motivation of quality assurance, machine learning techniques were trained to classify Norwegian radiology reports of paediatric CT examinations according to their description of abnormal findings. METHODS: 13.506 reports from CT-scans of children, 1000 reports from CT scan of adults and 1000 reports from X-ray examination of adults were classified as positive or negative by a radiologist, according to the presence of abnormal findings. Inter-rater reliability was evaluated by comparison with a clinician's classifications of 500 reports. Test-retest reliability of the radiologist was performed on the same 500 reports. A convolutional neural network model (CNN), a bidirectional recurrent neural network model (bi-LSTM) and a support vector machine model (SVM) were trained on a random selection of the children's data set. Models were evaluated on the remaining CT-children reports and the adult data sets. RESULTS: Test-retest reliability: Cohen's Kappa = 0.86 and F1 = 0.919. Inter-rater reliability: Kappa = 0.80 and F1 = 0.885. Model performances on the Children-CT data were as follows. CNN: (AUC = 0.981, F1 = 0.930), bi-LSTM: (AUC = 0.978, F1 = 0.927), SVM: (AUC = 0.975, F1 = 0.912). On the adult data sets, the models had AUC around 0.95 and F1 around 0.91. CONCLUSIONS: The models performed close to perfectly on its defined domain, and also performed convincingly on reports pertaining to a different patient group and a different modality. The models were deemed suitable for classifying radiology reports for future quality assurance purposes, where the fraction of the examinations with abnormal findings for different sub-groups of patients is a parameter of interest.

Long-term prognosis for patients admitted to a medical intermediate care unit. / Langtidsprognose for pasienter innlagt i en medisinsk overvåkningsavdeling.

BACKGROUND: The intermediate care unit at Akershus University Hospital treats patients with incipient or manifest organ failure. Selecting patients who might benefit from treatment in an intermediate care unit is challenging. Few data are available on long-term survival of patients treated in medical intermediate care units and on how assumed favourable and unfavourable prognostic factors predict long-term survival in this population. MATERIAL AND METHOD: Comorbidity, reason for admission and whether an infection was a direct or contributory reason for the admission were prospectively registered for patients in the unit in 2014 and 2016. We registered mortality up to six years after the admission and conducted a logistic regression analysis with three-year survival as the outcome variable. RESULTS: Of the 2 170 included patients, 153 (7 %) died in the intermediate care unit. Of the 2 017 patients who were discharged alive from the intermediate care unit, 55 % were still alive three years later, including 28 % of older patients aged over 80 years and 23 % of patients with cancer. Age, malignancy, other comorbidity and infection were predictors of mortality. INTERPRETATION: Many patient groups in an intermediate care unit have a poor long-term prognosis. However, people older than 80 years, cancer patients or patients with another serious comorbidity may live long after their stay in an intermediate care unit, and the fact of belonging to these groups should not be an independent reason for withholding treatment.

Capacity and patient flow planning in post-term pregnancy outpatient clinics: a computer simulation modelling study.

BACKGROUND: The demand for a large Norwegian hospital's post-term pregnancy outpatient clinic has increased substantially over the last 10 years due to changes in the hospital's catchment area and to clinical guidelines. Planning the clinic is further complicated due to the high did not attend rates as a result of women giving birth. The aim of this study is to determine the maximum number of women specified clinic configurations, combination of specified clinic resources, can feasibly serve within clinic opening times. METHODS: A hybrid agent based discrete event simulation model of the clinic was used to evaluate alternative configurations to gain insight into clinic planning and to support decision making. Clinic configurations consisted of six factors: X0: Arrivals. X1: Arrival pattern. X2: Order of midwife and doctor consultations. X3: Number of midwives. X4: Number of doctors. X5: Number of cardiotocography (CTGs) machines. A full factorial experimental design of the six factors generated 608 configurations. RESULTS: Each configuration was evaluated using the following measures: Y1: Arrivals. Y2: Time last woman checks out. Y3: Women's length of stay (LoS). Y4: Clinic overrun time. Y5: Midwife waiting time (WT). Y6: Doctor WT. Y7: CTG connection WT. Optimisation was used to maximise X0 with respect to the 32 combinations of X1-X5. Configuration 0a, the base case Y1 = 7 women and Y3 = 102.97 [0.21] mins. Changing the arrival pattern (X1) and the order of the midwife and doctor consultations (X2) configuration 0d, where X3, X4, X5 = 0a, Y1 = 8 woman and Y3 86.06 [0.10] mins. CONCLUSIONS: The simulation model identified the availability of CTG machines as a bottleneck in the clinic, indicated by the WT for CTG connection effect on LoS. One additional CTG machine improved clinic performance to the same degree as an extra midwife and an extra doctor. The simulation model demonstrated significant reductions to LoS can be achieved without additional resources, by changing the clinic pathway and scheduling of appointments. A more general finding is that a simulation model can be used to identify bottlenecks, and efficient ways of restructuring an outpatient clinic.

Surgical site infection after hip fracture - mortality and risk factors: an observational cohort study of 1,709 patients.

Background and purpose - Surgical site infection (SSI) is a devastating complication of hip fracture surgery. We studied the contribution of early deep SSI to mortality after hip fracture surgery and the risk factors for deep SSI with emphasis on the duration of surgery.Patients and methods - 1,709 patients (884 hemi-arthroplasties, 825 sliding hip screws), operated from 2012 to 2015 at a single center were included. Data were obtained from the Norwegian Hip Fracture Register, the electronic hospital records, the Norwegian Surveillance System for Antibiotic Use and Hospital-Acquired Infections, and the Central Population Register.Results - The rate of early (≤ 30 days) deep SSI was 2.2% (38/1,709). Additionally, for hemiarthroplasties 7 delayed (> 30 days, ≤ 1 year) deep SSIs were reported. In patients with early deep SSI 90-day mortality tripled (42% vs. 14%, p < 0.001) and 1-year mortality doubled (55% vs. 24%, p < 0.001). In multivariable analysis, early deep SSI was an independent risk factor for mortality (RR 2.4 for 90-day mortality, 1.8 for 1-year mortality, p < 0.001). In univariable analysis, significant risk factors for early and delayed deep SSI were cognitive impairment, an intraoperative complication, and increasing duration of surgery. However, in the multivariable analysis, duration of surgery was no longer a significant risk factor.Interpretation - Early deep SSI is an independent risk factor for 90-day and 1-year mortality after hip fracture surgery. After controlling for observed confounding, the association between duration of surgery and early and delayed deep SSI was not statistically significant.

Clinical validation of a novel automated cell-free DNA screening assay for trisomies 21, 13, and 18 in maternal plasma.

OBJECTIVE: To evaluate clinical performance of a new automated cell-free (cf)DNA assay in maternal plasma screening for trisomies 21, 18, and 13, and to determine fetal sex. METHOD: Maternal plasma samples from 1200 singleton pregnancies were analyzed with a new non-sequencing cfDNA method, which is based on imaging and counting specific chromosome targets. Reference outcomes were determined by either cytogenetic testing, of amniotic fluid or chorionic villi, or clinical examination of neonates. RESULTS: The samples examined included 158 fetal aneuploidies. Sensitivity was 100% (112/112) for trisomy 21, 89% (32/36) for trisomy 18, and 100% (10/10) for trisomy 13. The respective specificities were 100%, 99.5%, and 99.9%. There were five first pass failures (0.4%), all in unaffected pregnancies. Sex classification was performed on 979 of the samples and 99.6% (975/979) provided a concordant result. CONCLUSION: The new automated cfDNA assay has high sensitivity and specificity for trisomies 21, 18, and 13 and accurate classification of fetal sex, while maintaining a low failure rate. The study demonstrated that cfDNA testing can be simplified and automated to reduce cost and thereby enabling wider population-based screening.

Fewer ischemic strokes, despite an ageing population: stroke models from observed incidence in Norway 2010-2015.

BACKGROUND: Stroke incidence rates have fallen in high-income countries over the last several decades, but findings regarding the trend over recent years have been mixed. The aim of the study was to describe and model temporal trends in incidence of stroke by age and sex between 2010 and 2015 in Norway, and to generate incidence projections towards year 2040. METHODS: All recorded strokes in Norway between 2010 and 2015 were extracted from the National Patient Registry and the National Cause of Death Registry. We report incidence by age, sex, and year; in raw numbers, per 100,000 person-years, by WHO and European standard populations; and generated statistical models by stroke type, age, sex, and year; and projected stroke incidence toward year 2040. RESULTS: The data covered 30.1 million person-years at risk, 53431 unique individuals hospitalized with a primary stroke diagnosis, and 6315 additional individuals registered as dead due to stroke. From 2010 to 2015, individuals suffering stroke per 100,000 person-years dropped from 239 to 195 (208 to 177 excluding immediate deaths). The decline was driven by ischemic strokes, with a statistically non-significant time trend for hemorrhagic stroke. CONCLUSIONS: The age-dependent incidence of ischemic strokes in Norway is declining rapidly, and more than compensates for the growth and ageing of the population. Comparisons with historic incidence statistics show that the reduction in incidence rates has accelerated over the last two decades.

Fast track hip fracture care and mortality - an observational study of 2230 patients.

BACKGROUND: Hip fracture patients are frail and have a high mortality. We investigated whether the introduction of fast track care reduced the 30-day mortality after hip fractures. METHODS: Fast track hip fracture care was established at our institution in October 2013. Data from the Norwegian Hip Fracture Register and electronic hospital records were merged for 2230 hip fracture patients operated in our department from January 2012 through December 2015. 1090 of these patients were operated before (conventional treatment group) and 1140 patients were operated after the introduction of fast track care (fast track group). Data were analysed by univariate analysis and binary logistic regression. RESULTS: Mortality did not differ significantly between the conventional treatment group and the fast track group at 30 days (7.9% vs. 6.5%), 90 days (13.5% vs. 12.5%) and one year (22.8% vs. 22.8%). Median admission time and time to surgery were significantly shorter in the fast track group than in the conventional treatment group (1.1 h vs. 3.9 h and 23.6 h vs. 25.7 h, both p <  0.0001). The 30-day reoperation rate was significantly lower in the fast track group compared to the conventional treatment group (odds ratio = 0.35 (95% CI: 0.15-0.84), p = 0.019). A composite 30-day outcome (reoperation, surgical site infection and/or death) was significantly less frequent in the fast track group (8.1%) than in the conventional treatment group (10.7%) in unadjusted analysis (p = 0.006), but not after adjusting for age, gender, cognitive impairment and ASA score (odds ratio = 0.85 (95% CI: 0.63-1.16), p = 0.31, 8.0% missing). Reoperations within 1 year, surgical site infections, 30-day readmissions and length of hospital stay did not differ significantly between the conventional treatment group and the fast track group. CONCLUSIONS: Fast track hip fracture care is safe. However, we observed no statistically significant change in 30-day, 90-day or 1-year mortality after the introduction of fast track hip fracture care. TRIAL REGISTRATION: The study was registered retrospectively at ClinicalTrials.gov (Protocol Record 284907 ) 6 December 2016.

Identifying menstrual migraine- improving the diagnostic criteria using a statistical method.

OBJECTIVE: To develop a robust statistical tool for the diagnosis of menstrually related migraine. BACKGROUND: The International Classification of Headache Disorders (ICHD) has diagnostic criteria for menstrual migraine within the appendix. These include the requirement for menstrual attacks to occur within a 5-day window in at least [Formula: see text] menstrual cycles ([Formula: see text]-criterion). While this criterion has been shown to be sensitive, it is not specific. Yet in some circumstances, for example to establish the underlying pathophysiology of menstrual attacks, specificity is also important, to ensure that only women in whom the relationship between migraine and menstruation is more than a chance occurrence are recruited. METHODS: Using a simple mathematical model, a Markov chain, to model migraine attacks we developed a statistical criterion to diagnose menstrual migraine (sMM). We then analysed a data set of migraine diaries using both the [Formula: see text]-criterion and the sMM. RESULTS: sMM was superior to the [Formula: see text]-criterion for varying numbers of menstrual cycles and increased in accuracy with more cycle data. In contrast, the [Formula: see text]-criterion showed maximum sensitivity only for three cycles, although specificity increased with more cycle data. CONCLUSIONS: While the ICHD [Formula: see text]-criterion is a simple screening tool for menstrual migraine, the sMM provides a more specific diagnosis and can be applied irrespective of the number of menstrual cycles recorded. It is particularly useful for clinical trials of menstrual migraine where a chance association between migraine and menstruation must be excluded.

Accurate whole-genome sequencing and haplotyping from 10 to 20 human cells.

Recent advances in whole-genome sequencing have brought the vision of personal genomics and genomic medicine closer to reality. However, current methods lack clinical accuracy and the ability to describe the context (haplotypes) in which genome variants co-occur in a cost-effective manner. Here we describe a low-cost DNA sequencing and haplotyping process, long fragment read (LFR) technology, which is similar to sequencing long single DNA molecules without cloning or separation of metaphase chromosomes. In this study, ten LFR libraries were made using only ∼100 picograms of human DNA per sample. Up to 97% of the heterozygous single nucleotide variants were assembled into long haplotype contigs. Removal of false positive single nucleotide variants not phased by multiple LFR haplotypes resulted in a final genome error rate of 1 in 10 megabases. Cost-effective and accurate genome sequencing and haplotyping from 10-20 human cells, as demonstrated here, will enable comprehensive genetic studies and diverse clinical applications.

The Burden of Stroke Mimics: Present and Future Projections.

BACKGROUND AND PURPOSE: An increasing proportion of patients presenting with suspected stroke prove to have other conditions, often referred to as stroke mimics. The aim of this study was to present a projection of the number of hospitalized strokes, transient ischemic attacks (TIAs), and stroke mimics in Norway up to the year 2050 based on expected demographic changes, to estimate the burden of stroke mimics in the coming decades. MATERIALS AND METHODS: This prospective study included all admissions to the stroke unit of Akershus University Hospital from March 1, 2012, to February 28, 2013. Relevant resource use was recorded. Based on the age- and sex-specific absolute incidences for the study period, the expected numbers of strokes, TIAs, and stroke mimics in the entire Norwegian population were computed for every fifth year for the period 2020-2050. RESULTS: We included 1881 admissions, of which 38.2% were stroke mimics. With constant age- and sex-dependent incidence rates, we estimated that the number of strokes and stroke mimics will respectively increase by 121.3% and 88.7% (men) and 97.6% and 71.7% (women). For hospital admission levels to stay constant at the 2013 level, an annual reduction of 2.1% and 1.7% (men) and 1.8% and 1.5% (women) must take place for strokes and mimics, respectively. CONCLUSIONS: A significant proportion of stroke unit admissions prove to have other conditions than stroke. With constant age- and sex-dependent incidence rates, the number of stroke mimics admissions will increase substantially over the next decades.

Epidemiology and prognoses in a medical intermediate care unit. / Epidemiologi og prognoser i en medisinsk overvåkningsavdeling.

BACKGROUND: The purpose of medical intermediate care units is the observation and treatment of patients with incipient or manifest organ failure. We wished to obtain data on which conditions result in admission to these units and the prognosis for these patients. MATERIAL AND METHOD: All patients admitted to the medical intermediate care unit at Akershus University Hospital in 2014 were registered prospectively with reason for admission, period of hospitalisation, degree of severity, comorbidity, last place of hospitalisation prior to medical intermediate care and treatment limitations (do-not-resuscitate order and/or do-not-intubate order). Mortality in the hospital and one year after hospitalisation were registered retrospectively. Multiple regression analysis was performed with hospital mortality as the outcome variable. RESULTS: Altogether 1369 patient hospitalisations for 1118 unique patients were included. The most frequent reasons for admission were pneumonia, chronic obstructive pulmonary disease, sepsis, poisonings and hyponatraemia. The degree of severity of the condition for which patients were admitted corresponded to that reported by intensive care departments in Norwegian local hospitals. A total of 13 % died during their stay in hospital and a further 14 % in the course of one year. The highest mortality was for patients with severe infection, cardiac failure and restrictive/neuromuscular respiratory disorder. The degree of severity, age, infection, comorbidity and ward as admitting unit were predictors of mortality during the hospitalisation period. Risk-adjusted mortality ratio of 0.64 satisfied the quality objective for intensive care departments (<0.7). A total of 5.6 % of hospitalisations in the medical intermediate care unit entailed transfer to the intensive care ward. INTERPRETATION: The degree of severity of the condition for which patients were admitted was high, and the treatment outcomes judged upon expected mortality were good. Medical intermediate care units can relieve pressure on wards with seriously ill patients without taking up intensive care beds.

Causes of higher symptomatic airway load in patients with chronic rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis display a variety of different phenotypes. The symptoms of disease are characterised by various signs and symptoms such as nasal congestion, nasal discharge, pressure sensation in the face and reduced or complete loss of smell.In a patient population undergoing functional endoscopic sinonasal surgery (FESS) for chronic rhinosinusitis, we wanted to investigate the clinical features and explore if the presence of biofilm, nasal polyps or other disease characteristic could serve as predictor for the symptomatic load. A patient group undergoing septoplasty without disease of the sinuses was included as control. METHODS: The Sinonasal outcome test (SNOT-20), EPOS visual analogue scale (VAS) and the Lund-Mackey CT score (LM CT score) were used to examine 23 patients with chronic rhinosinusitis without nasal polyps (CRSsNP), 30 patient with nasal polyps (CRSwNP) and 22 patients with septal deviation. Tissue samples were collected prospectively during surgery. The cohort has previously been examined for the presence of biofilm. RESULTS: Patients with CRSsNP and CRSwNP had significantly higher degree of symptoms compared to the septoplasty group (SNOT-20 scores of 39.8, 43.6 and 29.9, respectively, p = 0.034). There were no significant differences in the total SNOT-20 or VAS symptoms scores between the CRSsNP and CRSwNP subgroups. However patients with nasal polyps showed significantly higher scores of symptoms related to sinonasal discomfort such as cough, runny nose and need to blow nose (p = 0.011, p = 0.046, p = 0.001 respectively). Patients with nasal polyps showed a significantly higher LM CT score compared to patients without polyps (12.06 versus 8.00, p = 0.001). The presence of biofilm did not impact the degree of symptoms. CONCLUSION: The presence of nasal polyp formations in CRS patients was associated with a higher symptomatic airway load as compared to patients without polyps. These findings suggest that nasal polyps could be an indicator of more substantial sinonasal disease. The presence of biofilm did not impact the degree of symptoms, however, as biofilm seem to be a common feature of chronic rhinosinusitis (89% in this cohort), it is more likely to be involved in the development of the CRS, rather than being a surrogate marker for increased symptomatic load.

Pre-contact by telephone increases response rates to postal questionnaires in a population of stroke patients: an open ended randomized controlled trial.

BACKGROUND: A follow-up study on a cohort of stroke patients through a postal survey questionnaire 3 and 12 months after discharge from hospital was performed. The response rate at 3-months follow-up was lower than desired, and pre-contact by phone as a measure for increasing the response rate at 12 months was studied. METHODS: The study design was a randomized controlled trial on a cohort of 3 months follow-up-non-responders where the intervention group was pre-contacted with an aim to obtain an informal 'consent to receive' the questionnaire before the 12-months survey was mailed, and the control group was not. The primary outcome was 45 days response rate; secondary outcome was 365 days response rate. The main analysis followed the intention to treat principle. A secondary, per-protocol analysis (i.e. subjects who were not reached by phone were reassigned to the control group) is included. Also included is a rudimentary cost-utility analysis, where we estimated the cost per additional response. RESULTS: Of the 235 subjects, 116 were randomized to the intervention group and 119 to the control group. 10 were excluded due to death (7 in the IG and 3 in the CG), 6 due to dementia (3 in the IG and 3 in the CG), and 2 (1 in the IG and 1 in the CG) for other reasons. The primary outcome was a response rate of 42.9 % in the intervention group, and 26.8 % in the control group, giving p =0.014, with estimated OR of 2.04 (95 % CI [1.16,3.64]). The secondary outcome had p =0.009 with OR 2.10 (95 % CI [1.20,3.70]). The as-per-protocol analyses gave stronger results with p =0.001 and p =0.003, respectively. The cost-utility analysis gave a time cost of 1 working hour per additional response. CONCLUSIONS: The results are in line with previous research, and show that pre-contact has a positive effect on response rate also for a population of elderly with reduced health. Given the importance of high response rate in surveys, a cost of 1 working hour per additional response is likely to be worth while. TRIAL REGISTRATION: Registration with ISRCTN initiated on 05/21/2013 and finalised on 06/30/2014 with http://www.isrctn.com/ISRCTN31304930 . Following the prospective submission in May 2013, there were no subsequent changes to the protocol. The recruitment started on 01/06/13, after initiation of public registration.

Statistical testing of association between menstruation and migraine.

OBJECTIVE: To repair and refine a previously proposed method for statistical analysis of association between migraine and menstruation. BACKGROUND: Menstrually related migraine (MRM) affects about 20% of female migraineurs in the general population. The exact pathophysiological link from menstruation to migraine is hypothesized to be through fluctuations in female reproductive hormones, but the exact mechanisms remain unknown. Therefore, the main diagnostic criterion today is concurrency of migraine attacks with menstruation. Methods aiming to exclude spurious associations are wanted, so that further research into these mechanisms can be performed on a population with a true association. METHODS: The statistical method is based on a simple two-parameter null model of MRM (which allows for simulation modeling), and Fisher's exact test (with mid-p correction) applied to standard 2 × 2 contingency tables derived from the patients' headache diaries. Our method is a corrected version of a previously published flawed framework. To our best knowledge, no other published methods for establishing a menstruation-migraine association by statistical means exist today. RESULTS: The probabilistic methodology shows good performance when subjected to receiver operator characteristic curve analysis. Quick reference cutoff values for the clinical setting were tabulated for assessing association given a patient's headache history. CONCLUSIONS: In this paper, we correct a proposed method for establishing association between menstruation and migraine by statistical methods. We conclude that the proposed standard of 3-cycle observations prior to setting an MRM diagnosis should be extended with at least one perimenstrual window to obtain sufficient information for statistical processing.

Laparoscopic Lavage vs Primary Resection for Acute Perforated Diverticulitis: The SCANDIV Randomized Clinical Trial.

IMPORTANCE: Perforated colonic diverticulitis usually requires surgical resection, which is associated with significant morbidity. Cohort studies have suggested that laparoscopic lavage may treat perforated diverticulitis with less morbidity than resection procedures. OBJECTIVE: To compare the outcomes from laparoscopic lavage with those for colon resection for perforated diverticulitis. DESIGN, SETTING, AND PARTICIPANTS: Multicenter, randomized clinical superiority trial recruiting participants from 21 centers in Sweden and Norway from February 2010 to June 2014. The last patient follow-up was in December 2014 and final review and verification of the medical records was assessed in March 2015. Patients with suspected perforated diverticulitis, a clinical indication for emergency surgery, and free air on an abdominal computed tomography scan were eligible. Of 509 patients screened, 415 were eligible and 199 were enrolled. INTERVENTIONS: Patients were assigned to undergo laparoscopic peritoneal lavage (n = 101) or colon resection (n = 98) based on a computer-generated, center-stratified block randomization. All patients with fecal peritonitis (15 patients in the laparoscopic peritoneal lavage group vs 13 in the colon resection group) underwent colon resection. Patients with a pathology requiring treatment beyond that necessary for perforated diverticulitis (12 in the laparoscopic lavage group vs 13 in the colon resection group) were also excluded from the protocol operations and treated as required for the pathology encountered. MAIN OUTCOMES AND MEASURES: The primary outcome was severe postoperative complications (Clavien-Dindo score >IIIa) within 90 days. Secondary outcomes included other postoperative complications, reoperations, length of operating time, length of postoperative hospital stay, and quality of life. RESULTS: The primary outcome was observed in 31 of 101 patients (30.7%) in the laparoscopic lavage group and 25 of 96 patients (26.0%) in the colon resection group (difference, 4.7% [95% CI, -7.9% to 17.0%]; P = .53). Mortality at 90 days did not significantly differ between the laparoscopic lavage group (14 patients [13.9%]) and the colon resection group (11 patients [11.5%]; difference, 2.4% [95% CI, -7.2% to 11.9%]; P = .67). The reoperation rate was significantly higher in the laparoscopic lavage group (15 of 74 patients [20.3%]) than in the colon resection group (4 of 70 patients [5.7%]; difference, 14.6% [95% CI, 3.5% to 25.6%]; P = .01) for patients who did not have fecal peritonitis. The length of operating time was significantly shorter in the laparoscopic lavage group; whereas, length of postoperative hospital stay and quality of life did not differ significantly between groups. Four sigmoid carcinomas were missed with laparoscopic lavage. CONCLUSIONS AND RELEVANCE: Among patients with likely perforated diverticulitis and undergoing emergency surgery, the use of laparoscopic lavage vs primary resection did not reduce severe postoperative complications and led to worse outcomes in secondary end points. These findings do not support laparoscopic lavage for treatment of perforated diverticulitis. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01047462.

The effect of activity-based financing on hospital length of stay for elderly patients suffering from heart diseases in Norway.

BACKGROUND: Whether activity-based financing of hospitals creates incentives to treat more patients and to reduce the length of each hospital stay is an empirical question that needs investigation. This paper examines how the level of the activity-based component in the financing system of Norwegian hospitals influences the average length of hospital stays for elderly patients suffering from ischemic heart diseases. During the study period, the activity-based component changed several times due to political decisions at the national level. METHODS: The repeated cross-section data were extracted from the Norwegian Patient Register in the period from 2000 to 2007, and included patients with angina pectoris, congestive heart failure, and myocardial infarction. Data were analysed with a log-linear regression model at the individual level. RESULTS: The results show a significant, negative association between the level of activity-based financing and length of hospital stays for elderly patients who were suffering from ischemic heart diseases. The effect is small, but an increase of 10 percentage points in the activity-based component reduced the average length of each hospital stay by 1.28%. CONCLUSIONS: In a combined financing system such as the one prevailing in Norway, hospitals appear to respond to economic incentives, but the effect of their responses on inpatient cost is relatively meagre. Our results indicate that hospitals still need to discuss guidelines for reducing hospitalisation costs and for increasing hospital activity in terms of number of patients and efficiency.

Using stochastic simulation modelling to study occupancy levels of decentralised admission avoidance units in Norway.

Identifying alternatives to acute hospital admission is a priority for many countries. Over 200 decentralised municipal acute units (MAUs) were established in Norway to divert low-acuity patients away from hospitals. MAUs have faced criticism for low mean occupancy and not relieving pressures on hospitals. We developed a discrete time simulation model of admissions and discharges to MAUs to test scenarios for increasing absolute mean occupancy. We also used the model to estimate the number of patients turned away as historical data was unavailable. Our experiments suggest that mergers alone are unlikely to substantially increase MAU absolute mean occupancy as unmet demand is generally low. However, merging MAUs offers scope for up to 20% reduction in bed capacity, without affecting service provision. Our work has relevance for other admissions avoidance units and provides a method for estimating unconstrained demand for beds in the absence of historical data.