[18F]FE-PE2I PET is a feasible alternative to [123I]FP-CIT SPECT for dopamine transporter imaging in clinically uncertain parkinsonism

BACKGROUND

Dopamine transporter (DAT) imaging of striatum is clinically used in Parkinson's disease (PD) and neurodegenerative parkinsonian syndromes (PS) especially in the early disease stages. The aim of the present study was to evaluate the diagnostic performance of the recently developed tracer for DAT imaging [¹⁸F]FE-PE2I PET/CT to the reference standard [¹²³I]FP-CIT SPECT.

METHODS

Ninety-eight unselected patients referred for DAT imaging were included prospectively and consecutively and evaluated with [¹⁸F]FE-PE2I PET/CT and [¹²³I]FP-CIT SPECT on two separate days. PET and SPECT scans were categorized independently by two blinded expert readers as either normal, vascular changes, or mixed. Semiquantitative values were obtained for each modality and compared regarding effect size using Glass' delta.

RESULTS

Fifty-six of the [¹²³I]FP-CIT SPECT scans were considered abnormal (52 caused by PS, 4 by infarctions). Using [¹⁸F]FE-PE2I PET/CT, 95 of the 98 patients were categorized identically to SPECT as PS or non-PS with a sensitivity of 0.94 [0.84-0.99] and a specificity of 1.00 [0.92-1.00]. Inter-reader agreement for [¹⁸F]FE-PE2I PET with a kappa of 0.97 [0.89-1.00] was comparable to the agreement for [¹²³I]FP-CIT SPECT of 0.96 [0.76-1.00]. Semiquantitative values for short 10-min reconstructions of [¹⁸F]FE-PE2I PET/CT were comparable to longer reconstructions. The effect size for putamen/caudate nucleus ratio was significantly increased using PET compared to SPECT.

CONCLUSIONS

The high correspondence of [¹⁸F]FE-PE2I PET compared to reference standard [¹²³I]FP-CIT SPECT establishes [¹⁸F]FE-PE2I PET as a feasible PET tracer for clinical use with favourable scan logistics.

CHA2DS2-VASc below 3 predicts low one-year ischemic stroke risk in postoperative atrial fibrillation after CABG

Background

Ischemic stroke prevention is a major goal in patients with atrial fibrillation (AF). Neither the optimal risk assessment method, nor the risk-benefit-ratio of long-term use of oral anticoagulation (OAC) is, however, known in patients with new-onset AF (POAF) after cardiac surgery.

Purpose

To explore the feasibility of using the CHA2DS2-VASc scoring system in predicting the one-year ischemic stroke risk in patients with POAF after coronary artery bypass grafting (CABG).

Methods

All patients in Sweden with POAF after isolated CABG 2007–2017, with at least one year of follow-up, and without oral anticoagulation (OAC), were included in this observational, registry-based cohort study. POAF was defined as any new-onset AF during the index hospitalization for CABG. Primary endpoint was the one-year ischemic stroke risk at each step of the CHA2DS2-VASc score in POAF patients with at least one-year follow-up.

Results

Out of 6368 POAF patients without OAC neither at hospital discharge nor before the occurrence of events, 4467 (70.1%) had at least one year follow-up with altogether 124 ischemic strokes within one year from discharge. The one-year risk for ischemic stroke was <1% for a CHA2DS2-VASc score <3, 1–2% for a CHA2DS2-VASc score 3, and >2% for a CHA2DS2-VASc score ≥4. The area under the receiver-operating-characteristic curve for predicting ischemic stroke was 0.67 (95% CI 0.64–0-69).

Conclusions

The CHA2DS2-VASc score was suitable for predicting low risk for ischemic stroke during the first year after hospital discharge in patients with POAF after CABG. A risk <1% considered low was, however, observed at a considerably higher score than in patients with non-surgical/non-valvular AF described in previous studies.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swedish Heart-Lung Foundation (grant 20150587 and 20180560 to Anders Jeppsson)Region Västra Götaland (grant VGFOUREG-847811 to Anders Jeppsson and grant VGFOUREG-648981 to Amar Taha) Event rates during one year

Prognostic usefulness of planar 123I-MIBG scintigraphic images of myocardial sympathetic innervation in congestive heart failure: Follow-Up data from ADMIRE-HF

BACKGROUND

To evaluate whether planar 123I-MIBG myocardial scintigraphy predicts risk of death in heart failure (HF) patients up to 5 years after imaging.

METHODS AND RESULTS

Subjects from ADMIRE-HF were followed for approximately 5 years after imaging (964 subjects, median follow-up 62.7 months). Subjects were stratified according to the heart/mediastinum (H/M) ratio (< 1.60 vs ≥ 1.60) on planar 123I-MIBG scintigraphic images obtained at baseline in ADMIRE-HF. Cox proportional hazards models and Kaplan-Meier analyses were used to evaluate time to death, cardiac death, or arrhythmic events for subjects stratified by H/M ratio, baseline left ventricular ejection fraction (LVEF: < 25% and 25 to ≤ 35%), and by H/M strata within LVEF strata. All-cause mortality was 38.4% vs 20.9% and cardiac mortality was 16.8% vs 4.5%, in subjects with H/M < 1.60 vs ≥ 1.60, respectively (P < 0.05 for both comparisons). Subjects with preserved sympathetic innervation of the myocardium (H/M ≥ 1.60) were at significantly lower risk of all-cause and cardiac death, arrhythmic events, sudden cardiac death, or potentially life-threatening arrhythmias. Within LVEF strata, a trend toward a higher mortality for subjects with H/M < 1.60 was observed reaching significance for LVEF 25 to ≤ 35% only.

CONCLUSIONS

During a median follow-up of 62.7 months, patients with H/M ≥ 1.60 were at significantly lower risk of death and arrhythmic events independently of LVEF values.

Prognostic implications of supraventricular ectopy

Background

According to consensus atrial fibrillation (AF) is an irregular heart rhythm with absence of p-waves, lasting for at least 30 seconds. However, AF is most likely a continuous disease ranging from occasional bursts of AF-like activity to permanent AF, rather than a dichotomous condition. Regardless, the 30-second AF definition leaves cardiologists without clear guidelines on how to manage patients with shorter episodes of seemingly atrial fibrillation-like activity and/or an abundance of supraventricular ectopic beats.

Purpose

The aim of this study was to establish the prevalence and prognostic implication of frequent supraventricular ectopic beats, isolated, in bi- or trigeminy, and supraventricular tachycardias with different characteristics.

Methods

In the STROKESTOP I mass-screening study for AF in 75- and 76-year olds in Sweden, 7173 participants did 30-second intermittent ECG twice daily for two weeks. ECG-recordings from STROKESTOP I were re-evaluated using an automated algorithm to detect individuals with frequent supraventricular ectopic beats or runs. Detected episodes were manually re-examined to confirm the findings. The primary endpoint was atrial fibrillation as ascertained from the nationwide Swedish Patient register. Secondary endpoints were stroke and death. Median follow-up was 4.2 (3.8–4.4) years.

Results

Of the 6100 examined participants 85% were free of significant supraventricular arrhythmia. Frequent supraventricular ectopic beats were the most common arrhythmia, n=709 (11.6%), and irregular SVTs were more common than regular SVTs. During follow-up 387 participants developed AF, 161 had a stroke event and there were 354 deaths. Individuals with the most AF-like SVT, irregular and lacking p-waves, n=97 (1.6%), had the highest risk of developing AF (hazard ratio 4.3 (95% confidence interval 2.7–6.8), Figure 1. They also had an increased risk of death, 2.0 (1.1–3.8). We found no significant increase in stroke risk.

Conclusion

Progression of atrial arrhythmias from supraventricular ectopic beats to more organized arrhythmic episodes are associated with development of AF. Extended screening for AF should be considered in individuals with frequent supraventricular activity, especially in those with supraventricular tachycardias with AF characteristics.

Figure 1. Kaplan-Meier curve showing primary end-point event rate (atrial fibrillation) in participants with different arrhythmias.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): This study was supported by Stiftelsen Hjärtat, Boehringer Ingelheim, The Swedish Heart and Lung Association, Capio Forskningsstiftelse and Åke Wibergs Stiftelse. STROKESTOP I was founded by Stockholm County Council, the Swedish Heart & Lung Foundation, King Gustav V and Queen Victoria's Freemasons' Foundation, the Klebergska Foundation, the Tornspiran Foundation, the Scientific Council of Halland Region, the Southern Regional Healthcare Committee, the Swedish Stroke Fund, Boehringer-Ingelheim, Bayer and Pfizer. Emma Svennberg is supported by the Stockholm County Council (Clinical postdoctorial appointment) and has received research funding from the Swedish Society of Medicine.

The association between atrial fibrillation and pulmonary embolism

Background and objectives

Previous studies have suggested that atrial fibrillation is a risk factor for pulmonary embolism. Oral anticoagulant therapy is the mainstay of treatment for atrial fibrillation and pulmonary embolism. We wanted to investigate if atrial fibrillation remained associated with the development of pulmonary embolism if oral anticoagulant treatment was accounted for.

Method

In this retrospective registry study a random sample of 20% of the adult Swedish population comprising approximately 1.5 million individuals were included during 2010–2017 in a cohort analysis. The endpoint was acute pulmonary embolism. In the cohort study, patients were analysed according to oral anticoagulant treatment and presence of atrial fibrillation at baseline.

Results

The group with atrial fibrillation was &gt;25 years older than the group without and had almost three times higher incidence of pulmonary embolism (2.91 vs 1.09 /1000 year at risk, p&lt;0.001). Individuals with atrial fibrillation on oral anticoagulant therapy had a lower risk of pulmonary embolism in multi-variable analysis (HR 0.59, CI 0.45–0.77). In the unadjusted analysis participants with atrial fibrillation without oral anticoagulant therapy showed an increased risk of pulmonary embolism (HR 3.33, CI 3.05–3.63). However, after multi-variable adjustment this association disappeared (HR 0.98, CI 0.89–1.07). In the entire atrial fibrillation cohort, no association was seen with the development of pulmonary embolism after multi-variable adjustment (HR 0.92, CI 0.84–1.01). The higher rate of pulmonary embolism among patients with atrial fibrillation can be fully explained by differences in age and co-morbidity.

Conclusion

Atrial fibrillation does not appear to be a clinically relevant risk factor for pulmonary embolism. Oral anticoagulant therapy protects against the development of pulmonary embolism in patients with atrial fibrillation.

Associations with pulmonary embolism

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): The main author has received funding from Stockholm County Council (Clinical postdoctorial appointment)

Use of oral anticoagulants after ischaemic stroke in patients with atrial fibrillation and cancer

BACKGROUND AND OBJECTIVES

The use of oral anticoagulants (OACs) amongst patients with atrial fibrillation (AF) has increased in the last decade. We aimed to describe temporal trends in the utilization of OACs for secondary prevention after ischaemic stroke amongst patients with AF and active cancer.

METHODS

This is a cross-sectional and cohort study of patients with active cancer (n = 1518) and without cancer (n = 50 953) in the Swedish national register Riksstroke, including all patients with ischaemic stroke between 1 July 2005 and 30 December 2017, discharged with AF. Prescription and dispensation before and after the introduction of nonvitamin K OACs (NOACs) in late 2011 were compared. We used logistic and Cox regression to analyse associations with OAC use, adjusting for hospital clustering and the competing risk of death.

RESULTS

The proportion of cancer patients with AF prescribed OACs at discharge after ischaemic stroke increased by 40.2% after 2011, compared with 69.3% in noncancer patients during the same period. Stroke and bleeding risk scores remained similar between patients with and without cancer. OAC dispensation during the following year did not increase as much in cancer patients (43.8% to 64.5%) as that in noncancer patients (46.0% to 74.9%), and the median time to OAC dispensation or censoring was significantly longer in cancer patients (94 vs. 30 days).

CONCLUSION

OAC treatment in poststroke patients with AF and active cancer has increased after the introduction of NOACs. However, the growing treatment gap in these patients compared to that in noncancer patients raises the possibility of underutilization.

2225“New-onset atrial fibrillation efter cardiac surgery is associated with increased long-term morbidity and mortality”: a population-based study from the SWEDEHEART-registry

Background

New-onset postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery, but the prognostic implications are not settled. In contrast to previous reports, a recent Danish study in coronary bypass surgery (CABG) patients (Butt et al. JAMA Cardiol 2018) did not show any increased risk for thromboembolic complications in POAF patients.

Purpose

To compare long-term outcome in patients with vs. without POAF after CABG.

Methods

All CABG patients in Sweden 2005–2015 (n=38040) were included in a retrospective population-based cohort study. Data from the SWEDEHEART registry, the National Patient Registry and the National Population Registry were merged. POAF was defined as any new-onset atrial fibrillation (AF) episode up to the 30thpostoperative day. Inverse Probability Treatment Weighting (IPTW) adjusted Cox regression models were used to compare outcome variables after the first 30 postoperative days until the end of follow-up (median 5 years, range 0–10). The models were adjusted for age, gender, CHA2DS2-VASc score, co-morbidity, and medications.

Results

The mean age of the entire cohort was 68 years, 79% were men and 90% had a CHA2DS2-VASc score ≥2. The incidence of POAF was 28.5% (10845/38040). During follow-up POAF, patients had a significantly higher adjusted risk for all-cause mortality [Hazard Ratio (HR) 1.16 (95% CI 1.09–1.24)], ischemic stroke [HR 1.19 (1.09–1.30)], transient ischemic attack [HR 1.17 (1.03–1.33)], pulmonary embolism [HR 1.24 (1.01–1.54)], myocardial infarction [HR 1.14 (1.04–1.25)], heart failure hospitalizations [HR.1.46 (1.35–1.59)] and recurrent AF [HR 4.33 (4.09–4.65)].

Conclusions

POAF was in this comparatively large study associated with increased risk for mortality and morbidity during long-term follow-up after CABG and is hence not a trivial complication.

209Glucose is associated with future atrial fibrillation and heart failure already at prediabetes levels, a 19 year follow up of 243,665 subjects

Background

Dysglycaemia is associated with cardiovascular disease even below the diagnostic diabetes threshold. Atrial fibrillation (AF) has been found to be associated with the metabolic syndrome and life-style changes after AF have been found to reduce recurrence of AF.

Purpose

We explored the association glucose and risk of first event of AF, HF and combined event.

Methods

Subject with fasting glucose in the AMORIS cohort, obtained 1985–1996 at routine occupational health check-ups or primary care in the Stockholm area were included. Subjects with prevalent AF, HF, ischemic heart disease, revascularization and cerebrovascular disease were excluded. Glucose levels were categorised as low (<3.9 mmol/L), normal (3.9–6.0mmol/L), impaired (IFG; 6.1–6.9 mmol/L) and diabetes (≥7.0 mmol/L or a diabetes diagnosis) according to WHO definition in 2006. First events of AF, HF or a combined event was identified until December 2011 by linkage to national registries. Information on co-morbidities was obtained from the National Patient Register. Hazard ratios (HR and 95% CI) by glucose group for AF and heart failure were calculated using Cox proportional hazards with attained age as timescale and adjusting for gender, total cholesterol and triglycerides. The change in AF risk by increasing glucose level was described by using splines (Figure).

Results

243 665 subjects with mean age 48.3 at index date, 54% male were included. During a mean follow-up time of 19.1 years and 4,7 million person years, 23 522 events of AF, 21 411 events of HF and 35 131 combined events occurred. The proportion with IFG and diabetes were 3.2% and 3.3% respectively. In the diabetes group about half were diagnosed prevalent cases (1.5%). Glucose was continuously associated with developement of AF (Table and Figure) and even more of HF (Table).

Events (n) and HR by glucose category Atrial fibrillation Heart failure Combined event Event HR [95% CI] Event HR [95% CI] Event HR [95% CI] Low 405 0.97 [0.88–1.08] 326 0.97 [0.87–1.08] 598 1.00 [0.92–1.09] Normal 20 663 1.00 17 811 1.00 30 159 1.00 IFG 1185 1.20 [1.13–1.28] 1319 1.43 [1.35–1.51] 1901 1.30 [1.24–1.36] Diabetes 1269 1.28 [1.20–1.35] 1955 2.19 [2.08–2.29] 2473 1.73 [1.66–1.81] Events (n) of AF, HF and combined and HR (95% CI) by fasting glucose category.

HR for AF by glucose level spline graph

Conclusion

Dysglycaemia, including glucose levels below the diabetes threshold, is continuously associated with future risk of both AF and HF. These data are important considering the large population with undetected dysglycaemia at risk for AF and HF where preventive measures including life-style changes could be of importance even before the onset of overt diabetes.

Acknowledgement/Funding

Swedish Heart and Lung foundation

Extrastriatal dopamine D2/3 receptors and cortical grey matter volumes in antipsychotic-naïve schizophrenia patients before and after initial antipsychotic treatment

OBJECTIVES

Long-term dopamine D_2/3 receptor blockade, common to all antipsychotics, may underlie progressive brain volume changes observed in patients with chronic schizophrenia. In the present study, we examined associations between cortical volume changes and extrastriatal dopamine D_2/3 receptor binding potentials (BP_ND) in first-episode schizophrenia patents at baseline and after antipsychotic treatment.

METHODS

Twenty-two initially antipsychotic-naïve patients underwent magnetic resonance imaging (MRI), [¹²³I]epidepride single-photon emission computerised tomography (SPECT), and psychopathology assessments before and after 3 months of treatment with either risperidone (N = 13) or zuclopenthixol (N = 9). Twenty healthy controls matched on age, gender and parental socioeconomic status underwent baseline MRI and SPECT.

RESULTS

Neither extrastriatal D_2/3 receptor BP_ND at baseline, nor blockade at follow-up, was related to regional cortical volume changes. In post-hoc analyses excluding three patients with cannabis use we found that higher D_2/3 receptor occupancy was significantly associated with an increase in right frontal grey matter volume.

CONCLUSIONS

The present data do not support an association between extrastriatal D_2/3 receptor blockade and extrastriatal grey matter loss in the early phases of schizophrenia. Although inconclusive, our exclusion of patients tested positive for cannabis use speaks to keeping attention to potential confounding factors in imaging studies.

Increased Motor Activity During REM Sleep Is Linked with Dopamine Function in Idiopathic REM Sleep Behavior Disorder and Parkinson Disease

STUDY OBJECTIVES

Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by impaired motor inhibition during REM sleep, and dream-enacting behavior. RBD is especially associated with α-synucleinopathies, such as Parkinson disease (PD). Follow-up studies have shown that patients with idiopathic RBD (iRBD) have an increased risk of developing an α-synucleinopathy in later life. Although abundant studies have shown that degeneration of the nigrostriatal dopaminergic system is associated with daytime motor function in Parkinson disease, only few studies have investigated the relation between this system and electromyographic (EMG) activity during sleep. The objective of this study was to investigate the relationship between the nigrostriatal dopamine system and muscle activity during sleep in iRBD and PD.

METHODS

10 iRBD patients, 10 PD patients with PD, 10 PD patients without RBD, and 10 healthy controls were included and assessed with (123)I-N-omega-fluoropropyl-2-beta-carboxymethoxy-3beta-(4-iodophenyl) nortropane ((123)I-FP-CIT) Single-photon emission computed tomography (SPECT) scanning ((123)I-FP-CIT SPECT), neurological examination, and polysomnography.

RESULTS

iRBD patients and PD patients with RBD had increased EMG-activity compared to healthy controls. (123)I-FP-CIT uptake in the putamen-region was highest in controls, followed by iRBD patients, and lowest in PD patients. In iRBD patients, EMG-activity in the mentalis muscle was correlated to (123)I-FP-CIT uptake in the putamen. In PD patients, EMG-activity was correlated to anti-Parkinson medication.

CONCLUSIONS

Our results support the hypothesis that increased EMG-activity during REM sleep is at least partly linked to the nigrostriatal dopamine system in iRBD, and with dopamine function in PD.

Frontal D2/3 Receptor Availability in Schizophrenia Patients Before and After Their First Antipsychotic Treatment: Relation to Cognitive Functions and Psychopathology

BACKGROUND

We have previously reported associations between frontal D2/3 receptor binding potential positive symptoms and cognitive deficits in antipsychotic-naïve schizophrenia patients. Here, we examined the effect of dopamine D2/3 receptor blockade on cognition. Additionally, we explored the relation between frontal D2/3 receptor availability and treatment effect on positive symptoms.

METHODS

Twenty-five antipsychotic-naïve first-episode schizophrenia patients were examined with the Positive and Negative Syndrome Scale, tested with the cognitive test battery Cambridge Neuropsychological Test Automated Battery, scanned with single-photon emission computerized tomography using the dopamine D2/3 receptor ligand [(123)I]epidepride, and scanned with MRI. After 3 months of treatment with either risperidone (n=13) or zuclopenthixol (n=9), 22 patients were reexamined.

RESULTS

Blockade of extrastriatal dopamine D2/3 receptors was correlated with decreased attentional focus (r = -0.615, P=.003) and planning time (r = -0.436, P=.048). Moreover, baseline frontal dopamine D2/3 binding potential and positive symptom reduction correlated positively (D2/3 receptor binding potential left frontal cortex rho = 0.56, P=.003; D2/3 receptor binding potential right frontal cortex rho = 0.48, P=.016).

CONCLUSIONS

Our data support the hypothesis of a negative influence of D2/3 receptor blockade on specific cognitive functions in schizophrenia. This is highly clinically relevant given the well-established association between severity of cognitive disturbances and a poor functional outcome in schizophrenia. Additionally, the findings support associations between frontal D2/3 receptor binding potential at baseline and the effect of antipsychotic treatment on positive symptoms.

Macrophage Phenotype Is Associated With the Regenerative Response in Experimental Replacement of the Porcine Esophagus

A porcine model for bridging circumferential defects in the intrathoracic esophagus has been developed in order to improve the treatment of children born with long-gap esophageal atresia. The aim of this study was to identify factors beneficial for tissue regeneration in the bridging area in this model and to describe the histological progression 20 days after replacement with a silicone-stented Biodesign mesh. Resection of 3 cm of intrathoracic esophagus and replacement with a bridging graft was performed in six newly weaned piglets. They were fed through a gastrostomy for 10 days, and then had probe formula orally for another 10 days prior to sacrifice. Two out of six piglets had stent loss prior to sacrifice. In the four piglets with the stent in place, a tissue tube, with visible muscle in the wall, was seen at sacrifice. Histology showed that the wall of the healing area was well organized with layers of inflammatory cells, in-growing vessels, and smooth muscle cells. CD163+ macrophages was seen toward the esophageal lumen. In the animals where the stent was lost, the bridging area was narrow, and histology showed a less organized structure in the bridging area without the presence of CD163+ macrophages. This study indicates that regenerative healing was seen in the porcine esophagus 20 days after replacement of a part of the intrathoracic esophagus with a silicone-stented Biodesign mesh, if the bridging graft is retained. If the graft is lost, the inflammatory pattern changes with invasion of proinflammatory, M1 macrophages in the entire wall, which seems to redirect the healing process toward scar formation.

Prepulse inhibition is associated with attention, processing speed, and 123I-FP-CIT SPECT in Parkinson's disease

BACKGROUND

Prepulse inhibition is a measure of sensorimotor gating, which reflects the ability to filter or 'gate' irrelevant information. Prepulse inhibition is dramatically altered in basal ganglia disorders associated with dysfunction in the midbrain dopaminergic system, and corresponding cognitive information processing deficits such as slowed processing speed. Parkinson's disease is characterised by the degeneration of the midbrain dopaminergic system and is associated with cognitive dysfunction, including slowed information processing. Although sensorimotor processes in Parkinson's disease have been extensively studied in relation to motor function, less is known about the potential role of sensorimotor processes in cognitive function.

OBJECTIVE

We investigated the relationship between prepulse inhibition, cognition and nigrostriatal dysfunction, as measured with 123I-FP-CIT-SPECT scanning, in patients with Parkinson's disease.

METHODS

38 Parkinson patients were assessed with prepulse inhibition, neuropsychological tests, and neurological investigation. A subset of these patients underwent 123I-FP-CIT-SPECT scanning.

RESULTS

Patients with a higher level of prepulse inhibition performed better on cognitive measures tapping attention and processing speed than patients with a lower level of prepulse inhibition. Furthermore, there were significant correlations between prepulse inhibition and 123I-FP-CIT uptake in the striatum.

CONCLUSIONS

Our results suggest that the level of prepulse inhibition is related to the efficiency of information processing in Parkinson's disease, and to the density of dopamine transporters in the striatum.

Swedish Early Separated Twins: Identification and Characterization

A sample of twins separated early in life has been identified in the Swedish Twin Registry. When the registry was compiled in 1961 (old cohort) and 1973 (young cohort), one or both members of 961 pairs indicated that they were separated by the age of 10. In May 1979, both members of 698 pairs were alive and were sent a questionnaire concerning the circumstances of separation. Items included reasons and timing of separation, biological relatedness of rearing parents, degree of contact after separation (including whether they lived in the same area, attended the same school, or lived together again), rough measures of selective placement, and current frequency of contact. An attempt was then made to categorize the pairs based on degree of separation. A total of 257 pairs met the criteria: rearing parents of one twin biologically unrelated to rearing parents of the cotwin, twins not living together again after separation, and contact after separation a few times a year or less. As much as 50% were separated by their first birthday, and 80% by the age of five. Various data from the twin registry are presented describing the entire sample of early separated twins as compared to a matched sample of twins reared together.

Missense dopamine transporter mutations associate with adult parkinsonism and ADHD

Parkinsonism and attention deficit hyperactivity disorder (ADHD) are widespread brain disorders that involve disturbances of dopaminergic signaling. The sodium-coupled dopamine transporter (DAT) controls dopamine homeostasis, but its contribution to disease remains poorly understood. Here, we analyzed a cohort of patients with atypical movement disorder and identified 2 DAT coding variants, DAT-Ile312Phe and a presumed de novo mutant DAT-Asp421Asn, in an adult male with early-onset parkinsonism and ADHD. According to DAT single-photon emission computed tomography (DAT-SPECT) scans and a fluoro-deoxy-glucose-PET/MRI (FDG-PET/MRI) scan, the patient suffered from progressive dopaminergic neurodegeneration. In heterologous cells, both DAT variants exhibited markedly reduced dopamine uptake capacity but preserved membrane targeting, consistent with impaired catalytic activity. Computational simulations and uptake experiments suggested that the disrupted function of the DAT-Asp421Asn mutant is the result of compromised sodium binding, in agreement with Asp421 coordinating sodium at the second sodium site. For DAT-Asp421Asn, substrate efflux experiments revealed a constitutive, anomalous efflux of dopamine, and electrophysiological analyses identified a large cation leak that might further perturb dopaminergic neurotransmission. Our results link specific DAT missense mutations to neurodegenerative early-onset parkinsonism. Moreover, the neuropsychiatric comorbidity provides additional support for the idea that DAT missense mutations are an ADHD risk factor and suggests that complex DAT genotype and phenotype correlations contribute to different dopaminergic pathologies.

Cognitive impairment in early-stage non-demented Parkinson's disease patients

OBJECTIVES

In Parkinson's disease (PD), Parkinson's disease dementia (PDD) and Parkinson's disease-mild cognitive impairment (PD-MCI) are common. PD-MCI is a risk factor for developing PDD. Knowledge of cognition in early-stages PD is essential in understanding and predicting the dementia process.

MATERIALS AND METHODS

We describe the cognitive profile in early-stage PD patients with no prior clinical suspicion of cognitive impairment, depression or psychiatric disturbances, and investigate possible features distinguishing patients with cognitive deficits, defining a PD-MCI risk-profile. Single Photon Emission Computerized Tomography (SPECT) DaT-scan and neurological examination confirmed the diagnosis. Mini-mental state examination-, Addenbrooke's Cognitive Examination, Unified Parkinson's Disease Rating Scale scoring, Hoehn &Yahr/Activity of Daily Living staging and a neuropsychological test battery were applied. Mild cognitive impairment patients were identified according to modified criteria by Troster necessarily omitting subjective cognitive complaints. 80 patients, mean age 61.0 years (SD 6.6), mean duration of disease 3.4 years (SD 1.2) were included. 76 patients were neuropsychologically tested.

RESULTS

26 (34%) patients fulfilled modified PD-MCI criteria, 18 (69%) of these showed episodic memory deficits, 14 (54%) executive dysfunction, 13 (50%) language/praxis deficits, 12 (46%) visuospatial/constructional deficits and 9 (35%) attention/working memory deficits. Cognitive impairment was associated with higher Unified Parkinson's Disease Rating scale (UPDRS)-, bradykinesia- and rigidity scores and more symmetric distribution of symptoms, but not tremor scores. Patients with cognitive impairment were less educated. Other demographic and clinical variables were comparable.

CONCLUSIONS

34% of early-stage PD patients without prior clinical suspicion of cognitive impairment exhibit cognitive impairment, which is associated to disease severity, especially bradykinesia, rigidity, axial symptoms and less asymmetry of motor symptoms, even at early disease stages and when cognitive symptoms are mild.

Atrial fibrillation prevalence revisited

BACKGROUND

The estimate of 0.4-1.0% prevalence of atrial fibrillation in the most recent American guidelines is based mainly on studies including patients with permanent atrial fibrillation (AF), although recent evidence shows that the stroke risk is similar with paroxysmal and persistent AF. Our objective was to determine the prevalence of AF in Sweden, irrespective of type and to what extent patients with AF receive adequate stroke prophylaxis.

METHOD

Retrospective study of patients with a clinical diagnosis of atrial fibrillation between 2005 and 2010 in the national Swedish Patient Register matched with data from the National Prescribed Drugs Register.

RESULTS

We identified 307 476 individuals with a diagnosis of atrial fibrillation. Of these, 209 141 were still alive on the last day of the inclusion period, signifying a prevalence of clinically diagnosed AF in Sweden of 2.9% of the total adult (≥20 years) population. Only 42% of them had purchased an oral anticoagulant within 6 months of the first presentation with AF during the study period. Those at the highest risk of stroke were those least likely to receive anticoagulant treatment. Undertreatment was common amongst women and individuals >80 years, whilst overtreatment was common amongst young men without risk factors.

CONCLUSION

The prevalence of atrial fibrillation is at least 2.9% of the Swedish adult population, not counting 'silent atrial fibrillation'. The official US figures probably underestimate the magnitude of the problem by a factor of 3-5. More than 80% had risk factors motivating anticoagulation therapy.

Severe and rapidly progressing cognitive phenotype in a SCA17-family with only marginally expanded CAG/CAA repeats in the TATA-box binding protein gene: a case report

Background

The autosomal dominant spinocerebellar ataxias (SCAs) confine a group of rare and heterogeneous disorders, which present with progressive ataxia and numerous other features e.g. peripheral neuropathy, macular degeneration and cognitive impairment, and a subset of these disorders is caused by CAG-repeat expansions in their respective genes. The diagnosing of the SCAs is often difficult due to the phenotypic overlap among several of the subtypes and with other neurodegenerative disorders e.g. Huntington’s disease.

Case presentation

We report a family in which the proband had rapidly progressing cognitive decline and only subtle cerebellar symptoms from age 42. Sequencing of the TATA-box binding protein gene revealed a modest elongation of the CAG/CAA-repeat of only two repeats above the non-pathogenic threshold of 41, confirming a diagnosis of SCA17. Normally, repeats within this range show reduced penetrance and result in a milder disease course with slower progression and later age of onset. Thus, this case presented with an unusual phenotype.

Conclusions

The current case highlights the diagnostic challenge of neurodegenerative disorders and the need for a thorough clinical and paraclinical examination of patients presenting with rapid cognitive decline to make a precise diagnosis on which further genetic counseling and initiation of treatment modalities can be based.

The safety of flecainide treatment of atrial fibrillation: long-term incidence of sudden cardiac death and proarrhythmic events

OBJECTIVE

To assess the safety of long-term treatment with flecainide in patients with atrial fibrillation (AF), particularly with regard to sudden cardiac death (SCD) and proarrhythmic events.

DESIGN

Retrospective, observational cohort study.

SETTING

Single-centre study at Örebro University Hospital, Sweden. Subjects.  A total of 112 patients with paroxysmal (51%) or persistent (49%) AF (mean age 60 ± 11 years) were included after identifying all patients with AF who initiated oral flecainide treatment (mean dose 203 ± 43 mg per day) between 1998 and 2006. Standard exclusion/inclusion criteria for flecainide were used, and flecainide treatment was usually combined with an atrioventricular-blocking agent (89%).

MAIN OUTCOME MEASURE

Death was classified as sudden or nonsudden according to standard definitions. Proarrhythmia was defined as cardiac syncope or life-threatening arrhythmia.

RESULTS

Eight deaths were reported during a mean follow-up of 3.4 ± 2.4 years. Compared to the general population, the standardized mortality ratios were 1.57 (95% confidence interval (CI) 0.68-3.09) for all-cause mortality and 4.16 (95% CI 1.53-9.06) for death from cardiovascular disease. Three deaths were classified as SCDs. Proarrhythmic events occurred in six patients (two each with wide QRS tachycardia, 1 : 1 conducted atrial flutter and syncope during exercise).

CONCLUSION

We found an increased incidence of SCD or proarrhythmic events in this real-world study of flecainide used for the treatment of AF. The findings suggest that further investigation into the safety of flecainide for the treatment of patients with AF is warranted.

(18)F-FDG PET/CT in a rare case of Stewart-Treves syndrome: future implications and diagnostic considerations

BACKGROUND

The aim of this article is to illustrate the possible applications of (18)F-fluorodeoxyglucose positron emission tomography/computer tomography ((18)F-FDG PET/CT) in chronic extremity lymphedema and its complications.

METHODS AND RESULTS

(18)F-FDG PET/CT findings in a rare case of Stewart-Treves Syndrome (STS), angiosarcoma secondary to chronic extremity lymphedema, are presented. Lymphedema of the extremities is a debilitating disease characterized by chronic swelling due to interstitial edema caused by insufficient lymphatic drainage capacity. Progression with skin thickening, subcutaneous fibrosis, and increased adipose tissue volume is common. Chronic inflammation has been suggested as a key pathophysiologic component. STS is a rare complication with a very poor prognosis; however, early diagnosis and radical treatment is associated with increased survival. Thus, accurate pretreatment staging is paramount. (18)F-FDG PET/CT is highly sensitive in detecting increased glucose metabolism as seen in many types of cancer and inflammation. The role of (18)F-FDG PET/CT in the management of lymphedema and its complications has to our knowledge yet to be described. This case documents high (18)F-FDG uptake in STS, but is at the same time an example of the low specificity of this imaging modality.

CONCLUSIONS

We suggest that (18)F-FDG PET/CT has the potential to become an important tool in the staging and treatment planning of Stewart-Treves syndrome. Furthermore, (18)F-FDG-accumulation may be a sensitive tool in detecting low grade inflammation in the skin and subcutis, which has been suggested to cause tissue remodeling in lymphedema progression. However, further studies are needed to elucidate this theory.

Novel mutation in ATP13A2 widens the spectrum of Kufor-Rakeb syndrome (PARK9)

Kufor-Rakeb syndrome (KRS) is a rare autosomal recessive inherited juvenile parkinsonian syndrome caused by mutations in ATP13A2. We describe six patients from a consanguineous Greenlandic Inuit family, homozygous for a novel frame-shift mutation in exon 22 of ATP13A2 (c.2473C>AA, p.Leu825AsnfsX32). Disease onset varied from 10 to 29 years of age, the latest reported, and the clinical features were highly variable within a wide spectrum of an extrapyramidal-pyramidal syndrome with cognitive/psychiatric features. Ataxia was seen in two patients and axonal neuropathy in one, features not previously related to KRS. Dopamine transporter scans showed symmetrical, severely reduced uptake in striatum in two patients. Magnetic resonance imaging was without atrophy in one patient despite disease duration of 17 years, and cerebral and cerebellar atrophy was seen in another patient after 4 years of disease duration. The molecular pathogenic mechanisms of ATP13A2 mutations are discussed. The observation that the mutant transcript is not degraded by nonsense-mediated RNA decay and the fact that none of the eight heterozygous carriers from the family have KRS symptoms suggest that the mutant protein does not interfere and destroy the function of the wild-type ATP13A2 protein.

Strict follow-up programme including CT and ¹⁸F-FDG-PET after curative surgery for colorectal cancer

AIM

The risk of local recurrence following curative surgery for colorectal cancer (CRC) is up to 50%. A rigorous follow-up program may increase survival. Guidelines on suitable methods for scheduled follow up examinations are needed. This study evaluates a strict follow-up program including carcinogenic embryonic antigen (CEA), chest X-ray, abdominal ultrasound (US), computed tomography (CT) and (18)F-FDG positron emission tomography (FDG-PET).

METHOD

A cohort of 132 patients, treated by surgery with curative intent for CRC, was included. Patients were followed prospectively with scheduled controls at 3, 6, 12 and 24 months after curative surgery. CEA, chest X-ray, US, CT and FDG-PET supplemented by clinical examination. The end-point was recurrence. Sensitivity and specificity was estimated 2 years after surgery.

RESULTS

Of the 132 patients included in the study, 25 experienced recurrence, detected at scheduled controls (n = 18) and at intervals between them (n = 7). The results of CT and FDG-PET were correlated with recurrence. CT combined with FDG-PET had the highest specificity and sensitivity.

CONCLUSION

A total of 72% of recurrences were detected at scheduled controls. The findings supported a strict follow-up program following curative surgery for colorectal cancer. FDG-PET combined with CT should be included in control programs.

Neurophysiological tests and neuroimaging procedures in non-acute headache (2nd edition)

BACKGROUND AND PURPOSE

A large number of instrumental investigations are used in patients with non-acute headache in both research and clinical fields. Although the literature has shown that most of these tools contributed greatly to increasing understanding of the pathogenesis of primary headache, they are of little or no value in the clinical setting.

METHODS

This paper provides an update of the 2004 EFNS guidelines and recommendations for the use of neurophysiological tools and neuroimaging procedures in non-acute headache (first edition). Even though the period since the publication of the first edition has seen an increase in the number of published papers dealing with this topic, the updated guidelines contain only minimal changes in the levels of evidence and grades of recommendation.

RESULTS

(i) Interictal EEG is not routinely indicated in the diagnostic evaluation of patients with headache. Interictal EEG is, however, indicated if the clinical history suggests a possible diagnosis of epilepsy (differential diagnosis). Ictal EEG could be useful in certain patients suffering from hemiplegic or basilar migraine. (ii) Recording evoked potentials is not recommended for the diagnosis of headache disorders. (iii) There is no evidence warranting recommendation of reflex responses or autonomic tests for the routine clinical examination of patients with headache. (iv) Manual palpation of pericranial muscles, with standardized palpation pressure, can be recommended for subdividing patient groups but not for diagnosis. Pain threshold measurements and EMG are not recommended as clinical diagnostic tests. (v) In adult and pediatric patients with migraine, with no recent change in attack pattern, no history of seizures, and no other focal neurological symptoms or signs, the routine use of neuroimaging is not warranted. In patients with trigeminal autonomic cephalalgia, neuroimaging should be carefully considered and may necessitate additional scanning of intracranial/cervical vasculature and/or the sellar/orbital/(para)nasal region. In patients with atypical headache patterns, a history of seizures and/or focal neurological symptoms or signs, MRI may be indicated. (vi) If attacks can be fully accounted for by the standard headache classification (IHS), a PET or SPECT scan will normally be of no further diagnostic value. Nuclear medical examinations of the cerebral circulation and metabolism can be carried out in subgroups of patients with headache for the diagnosis and evaluation of complications, when patients experience unusually severe attacks or when the quality or severity of attacks has changed. (vii) Transcranial Doppler examination is not helpful in headache diagnosis.

CONCLUSION

Although many of the examinations described in the present guidelines are of little or no value in the clinical setting, most of the tools, including thermal pain thresholds and transcranial magnetic stimulation, have considerable potential for differential diagnostic evaluation as well as for the further exploration of headache pathophysiology and the effects of pharmacological treatment.