Neural suppression in odor recognition memory.

Little is known about the neural basis of lower- and higher-order olfactory functions such as odor memory, compared with other sensory systems. The aim of this study was to explore neural networks and correlates associated with 3 functions: passive smelling (PS), odor encoding (OE), and in particular odor recognition memory (ORM). Twenty-six healthy participants were examined using functional magnetic resonance imaging conducted across 3 sessions, one for each function. Independent component analysis revealed a difference between sessions where a distinct ORM component incorporating hippocampus and posterior cingulate showed delayed triggering dissociated from odor stimulation and recognition. By contrasting Hit for ORM (target odors correctly recognized as old) and a combination of PS and detected odors from OE, we found significantly lower activations in amygdala, piriform cortex, insula, thalamus, and the inferior parietal lobule. Region of interest analysis including anterior insula, posterior cingulate gyrus, dentate gyrus, left middle frontal gyrus, amygdala, and piriform cortex demonstrated that Hit were associated with lower activations compared with other memory responses. In summary, our findings suggest that successful recognition of familiar odors (odor familiarity) is associated with neural suppression in the abovementioned regions of interest. Additionally, network including the hippocampus and posterior cingulate is engaged in a postrecognition process. This process may be related to incidental encoding of less familiar and more novel odors (odor novelty) and should be subject for future research.

Worldwide estimation of restless legs syndrome: a systematic review and meta-analysis of prevalence in the general adult population.

This systematic review, meta-analysis and meta-regression assessed the prevalence of restless legs syndrome (RLS) in the general adult population. Studies identified in Scopus, PubMed, Web of Science, and PsycInfo between January 2000 and February 2022 were included if they used a case-control or cross-sectional design and reported data regarding the prevalence of RLS. The protocol was pre-registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD42022300709). A total of 97 studies including 483,079 participants from 33 different countries met the eligibility criteria. The Newcastle Ottawa Scale was used to evaluate the methodological quality, and the fill-and-trim method was used to correct probable publication bias, while the jack-knife method was performed to assess small study effect. The corrected overall pooled prevalence of RLS was 3% (95% confidence interval [CI] 1.4%-3.8%). The pooled prevalence of RLS syndrome was affected by methodological quality (no data from non-respondents in the included studies), gender (higher among women), study design (lower prevalence in case-control versus cohort and cross-sectional studies). The figures for corrected pooled prevalence among men, women, alcohol consumers and smokers were 2.8% (95% CI 2%-3.7%); 4.7% (95% CI 3.2%-6.3%); 1.4% (95% CI 0%-4.2%); and 2.7% (95% CI 0%-5.3%), respectively. The prevalence among male and female participants was lower in community-based versus non-community-based studies. Moreover, the prevalence was higher in developed versus developing countries and among elders versus adults. In conclusion, RLS is a common disorder in the general adult population, with a higher prevalence in women; however, prevalence data are affected by study design and quality.

Impact of Ankle Brachial Index Calculations on Peripheral Arterial Disease Prevalence and as a Predictor of Cardiovascular Risk.

OBJECTIVE: The aim of this study was to estimate the prevalence and predictive accuracy for cardiovascular (CV) morbidity by using different ankle brachial index (ABI) calculation methods in the general population. METHODS: ABI measurements and questionnaire data were collected from 5 080 randomly selected citizens aged 60 - 90 years. A 10 year follow up with data from Swedish national health registries was carried out. ABI was calculated using as numerator the highest (ABI-HI) or the lowest (ABI-LO) ankle BP obtained in each leg. Subjects were defined as references or having peripheral arterial disease (PAD) based on ABI-LO (Group 1) or ABI-HI (Group 2). Prevalence, mortality, CV events and risk were then analysed for these three groups, and their predictive power by using the area under the curve (AUC). RESULTS: A total of 4 909 inhabitants were included in the cohort (References: 83.8%, Group 1: 6.7% and Group 2: 9.6%). The prevalence of PAD was 16% using ABI-LO, and 9.6% using ABI-HI. The 10 year all cause mortality for references and Groups 1 and 2 was 27.6%, 48.8%, and 67.2%, respectively. The overall age adjusted hazard ratio (95% confidence interval) for the composite outcome of CV mortality and a non-fatal CV event was 1.25 (1.06 - 1.49) for Group 1 and 2.11 (1.85 - 2.39) for Group 2. The prediction accuracy for ABI < 0.9 in predicting CV event measured with AUC was 0.60 for ABI-HI and 0.62 for ABI-LO. CONCLUSION: An ABI < 0.9 should be considered a strong risk marker for future CV morbidity. Applying the traditional ABI calculation method of using the highest measured ankle BP, a group of subjects with high CV risk may be overlooked for intervention, and this why the lowest ankle BP should be the preferred for risk stratification. However, as a single predictive tool an ABI < 0.9 cannot adequately discriminate which individual will have a future CV event regardless of calculation method used.

The a' velocity by tissue-Doppler echocardiography correlates to invasive mean left atrial pressure in patients with normal ejection fraction.

OBJECTIVES: To evaluate the correlation of a' velocity by tissue-Doppler measurements with invasively measured mean left atrial pressure in patients with normal ejection fraction. DESIGN: In this retrospective study, we evaluated the septal a', lateral a' and average a' velocity by tissue-Doppler echocardiography, in 125 in-hospital patients, 1-12 h before an elective pulmonary vein isolation due to intermittent atrial fibrillation, and compared to invasively measured mean left atrial pressure (LAP) during the invasive procedure. The patients, aged 35-81 years, had to be in sinus rhythm at both examinations, no atrial fibrillation during two procedures, no or mild valve disease and normal ejection fraction (>50%). RESULTS: Invasively measured mean LAP correlated well to septal a' (r = -0.435), lateral a' (r = -0.473) and average a' velocity (r = -0.491). Normal mean LAP (≤12 mmHg) was found in 95 patients and elevated mean LAP (>12 mmHg) in 30 patients. The patients with elevated mean LAP had a lower septal a' velocity (6.5 ± 2.7 vs 8.6 ± 2.3 cm/s; p < .01), lateral a' velocity (5.9 ± 2.3 vs 8.6 ± 2.1 cm/s; p < .01) and average a' velocity (6.2 ± 2.4 vs 8.8 ± 2.1 cm/s; p < .01) compared to patients with normal mean LAP. Septal a', lateral a' and average a' velocity were good predictors of elevated mean LAP with AUC of 0.78, 0.83 and 0.82. Average a' velocity with cut-off < 7.25 cm/s had a sensitivity of 83% and a specificity of 77% to predict elevated mean LAP. CONCLUSION: The a' velocity is a good indicator of mean LAP and might be considered in the evaluation of left ventricle filling pressure in patients with normal ejection fraction.

Group-based music intervention in Parkinson's disease - findings from a mixed-methods study.

OBJECTIVE: To evaluate a group-based music intervention in patients with Parkinson's disease. DESIGN: Parallel group randomized controlled trial with qualitative triangulation. SETTING: Neurorehabilitation in primary care. SUBJECTS: Forty-six patients with Parkinson's disease were randomized into intervention group (n = 26), which received training with the music-based intervention, and control group (n = 20) without training. INTERVENTIONS: The intervention was delivered twice weekly for 12 weeks. MAIN MEASURES: Primary outcome was Timed-Up-and-Go subtracting serial 7's (dual-task ability). Secondary outcomes were cognition, balance, concerns about falling, freezing of gait, and quality of life. All outcomes were evaluated at baseline, post-intervention, and three months post-intervention. Focus groups and individual interviews were conducted with the intervention group and with the delivering physiotherapists. RESULTS: No between-group differences were observed for dual-task ability. Between-group differences were observed for Falls Efficacy Scale (mean difference (MD) = 6.5 points; 95% confidence interval (CI) = 3.0 to 10.0, P = 0.001) and for Parkinson Disease Questionnaire-39 items (MD = 8.3; 95% CI = 2.7 to 13.8, P = 0.005) when compared to the control group post-intervention, but these were not maintained at three months post-intervention. Three themes were derived from the interviews: Expectations versus Results, Perspectives on Treatment Contents, and Key Factors for Success. CONCLUSION: Patient-reported outcomes and interviews suggest that the group-based music intervention adds value to mood, alertness, and quality of life in patients with Parkinson's disease. The study does not support the efficacy in producing immediate or lasting gains in dual-tasking, cognition, balance, or freezing of gait.

E/a' ratio is closely related to pulmonary vein flow profile in patients with normal ejection fraction.

Objectives. To compare the ability of the E/a' ratio and the recommended diastolic parameters in the American Society of Echocardiography (ASE) and the European Association of Cardiovascular Imaging (EACVI), in predicting a dominant diastolic pulmonary vein flow in patients with normal ejection fraction. Design. We retrospectively evaluated the diastolic function according to the ASE/EACVI guidelines, the S/D ratio and the septal, lateral and average E/a' ratio in 293 unselected in-hospital patients, aged 39-86 years, in sinus rhythm and with no or mild valve disease, having a normal systolic function (EF > 50%). Results. The S/D ratio had a positive association to septal, lateral and average E/a ratio (R2 = 0.25, 0.35 and 0.32). The association to average E/e' ratio, LA vol index and TR velocity was weak (R2 = 0.037, 0.033 and 0.087) and for e' velocity negatively. In patients with S/D ratio <1, septal, lateral, average E/a' ratio, average E/e ratio, LA vol index (p<.001) and TR velocity (p<.05) were significantly higher compared to patients with S/D ratio ≥1. No significant difference was seen in e' velocity. The septal, lateral and average E/a' ratio were significantly higher in patients with S/D ratio <1 regardless a normal or impaired diastolic function according to the ASE/EACVI guidelines (p<.001). The ASE/EACVI algorithm detected 21 patients with S/D ratio <1 compared to 28 patients using average E/a' ratio with cut-off >14. Conclusion: E/a' ratio might be a useful new diastolic parameter in patients with a normal ejection fraction as it is more closely related to the S/D ratio than the established ASE/EACVI diastolic parameters.

Tick-borne Encephalitis: Stroke-like Presentation.

Tick-borne encephalitis, caused by the tick-borne virus (TBEV), is endemic in central, eastern, and northern Europe eastwards through Russian Siberia and China. For the year 2009, the highest incidence in Scandinavian countries was in Sweden. The clinical symptoms have a wide spectrum. We report a unique case of clinical symptoms and radiological findings compatible with a stroke-like inflammatory lesion in the thalamus, suggesting microangiopathy from TBEV. Our case shows that TBEV could be a possible cause of stroke-like lesions.

Ten Year Mortality in Different Peripheral Arterial Disease Stages: A Population Based Observational Study on Outcome.

OBJECTIVE: The aim was to determine long-term mortality rates and the underlying cause of death for subjects with different peripheral arterial disease (PAD) stages in a population based setting. METHODS: A randomly selected population sample of 5080 subjects was enrolled in the study in 2004-2005. Participants completed health state questionnaires and underwent ankle brachial index (ABI) measurements for classification into PAD severity stages and reference subjects. A follow-up was conducted by the end of 2015 using data from Swedish governmental national registers for cause of death, which was then compared with PAD stage determined at baseline in 2005. RESULTS: The 10 year all cause mortality was 27% for reference cases, 56% for asymptomatic PAD (APAD), 63% for intermittent claudication (IC), and 75% for severe limb ischaemia (SLI). Among all PAD subjects, cardiovascular (CV) causes were the most common main cause of death (45%) and a CV event was present as either the main or one of the three most common contributing causes of death in 64% of the cases. The age adjusted hazard ratios for a main cause of death by a CV event were 1.9 (95% CI 1.5-2.3) for APAD, 2.6 (95% CI 2.1-3.4) for IC, and 3.5 (95% CI 2.3-5.2) for SLI. CONCLUSION: PAD subjects, including the APAD subjects, are still at high risk of CV death. The mortality risks are more than doubled in symptomatic PAD patients compared with reference subjects and increase by severity of PAD stage. Awareness and improved risk reduction management of PAD are still warranted.

E/a´ ratio a simple detector of left ventricular dysfunction in patients with decreased ejection fraction.

OBJECTIVES: Could a diastolic dysfunction and an increased LV-filling pressure according to ASE/EACVI guidelines be detected or ruled out by the E/a´ratio in patients with decreased ejection fraction. DESIGN: We retrospectively evaluated the diastolic function of 113 unselected in-hospital patients, aged 40-84 years, in sinus rhythm and with no or mild valve disease, having a decreased systolic function (EF ≤50%) using the new ASE/EACVI guidelines and compared these results with the E/a´ratio derived from the E wave in the mitral flow and the a´velocity in the tissue Doppler. RESULTS: The average E/a´ ratio is a strong predictor of a grade II-III diastolic dysfunction and an elevated left atrial pressure according to ASE/EACVI guidelines with an AUC of 0.92. An average E/a´ ratio with a cut-off >10 had a sensitivity of 97.6% and a negative predictive value of 98.2% in detecting or ruling out a grade II-III diastolic dysfunction and an elevated left atrial pressure according to the current guidelines. CONCLUSION: The average E/a´ ratio might be useful as a fast screening tool of a left ventricular dysfunction and an increased left ventricular filling pressure in patients with a decreased ejection fraction.

The a´ velocity in the tissue Doppler predicts S/D ratio <1 in patients with a normal ejection fraction.

OBJECTIVES: To compare the ability of the a´ velocity and the e´ velocity in predicting a dominant diastolic pulmonary vein flow (S/D ratio <1) in patients with normal ejection fraction. DESIGN: We retrospectively evaluated the diastolic function according to the ASE/EACVI guidelines, the S/D ratio and the septal, lateral and average a´ velocity in 293 unselected in-hospital patients, aged 39-86 years, in sinus rhythm and with no or mild valve disease, having a normal systolic function (EF >50%). RESULTS: There was a good linear correlation between the S/D ratio and the a´ velocity, but a tendency towards a negative correlation between the S/D ratio and the e´ velocity. S/D ratio <1 was seen in 43 patients. These patients had a significantly lower a´ velocity compared to those with S/D-ratio ≥1, septal (6,1 ± 2,4 v 8,8 ± 2,1 cm/s; p < .001) and lateral (6,0 ± 2,6 v 9,3 ± 2,5 cm/s; p < .001) No significant difference was seen in the septal e´ velocity (6,8 ± 2,4 v 6,8 ± 2,1 cm/s), lateral e´ velocity (9,4 ± 2,6 v 9,1 ± 2,8 cm/s) or in the ejection fraction (58,6 ± 4,4% v 58,7 ± 4,0%). A diastolic dysfunction was present in 62 patients, normal diastolic function in 231 patients. The a´ velocity was significantly lower in patients with S/D ratio <1 in both groups (p < .01). CONCLUSION: The a´ velocity is superior to the e´ velocity in predicting S/D ratio <1 in patients with normal ejection fraction regardless the ASE/EACVI diastolic classification. A failing left atrium seems to be the explanation.

Incidence and outcome of surgery for adult hydrocephalus patients in Sweden.

OBJECT: To present population-based and age related incidence of surgery and clinical outcome for adult patients operated for hydrocephalus, registered in the Swedish Hydrocephalus Quality Registry (SHQR). METHODS: All patients registered in SHQR during 2004-2011 were included. Data on age, gender, type of hydrocephalus and type of surgery were extracted as well as three months outcome for patients with idiopathic normal pressure hydrocephalus (iNPH). RESULTS: The material consisted of 2360 patients, 1229 men and 1131 women, age 63.8 ± 14.4 years (mean ± standard deviation (SD)). The mean total incidence of surgery was 5.1 ± 0.9 surgeries/100,000/year; 4.7 ± 0.9 shunt surgeries and 0.4 ± 0.1 endoscopic third ventriculostomies. For iNPH, secondary communicating hydrocephalus and obstructive hydrocephalus, the incidence of surgery was 2.2 ± 0.8, 1.9 ± 0.3 and 0.8 ± 0.1/100,000/year, respectively. During 2004-2011, the incidence of surgery increased in total (p = .044), especially in age groups 70-79 years and ≥80 years (p = .012 and p = .031). After surgery, 253 of 652 iNPH patients (38.8%) improved at least one step on the modified Rankin scale (mRS). Number needed to treat was 3.0 for improving one patient from unfavourable (mRS 3-5) to favourable (mRS 0-2). The mean score of a modified iNPH scale increased from 54 ± 23 preoperatively to 63 ± 25 postoperatively (p < .0001, n = 704), and 58% improved. No significant regional differences in incidence, surgical techniques or outcome were found. CONCLUSIONS: Incidence of hydrocephalus surgery increased significantly during 2004-2011, specifically in elderly patients. Surgical treatment of iNPH markedly improved functional independence, but the improvement rate was low compared to recent single- and multicentre studies. Thus, the potential for surgical improvement is likely lower than generally reported when treating patients as part of everyday clinical care.

Noninvasive assessment of glymphatic dysfunction in idiopathic normal pressure hydrocephalus with diffusion tensor imaging.

OBJECTIVE: Diffusion tensor imaging (DTI) along the perivascular space (ALPS) (DTI-ALPS)-by calculating the ALPS index, a ratio accentuating water diffusion in the perivascular space-has been proposed as a noninvasive, indirect MRI method for assessing glymphatic function. The main aim of this study was to investigate whether DTI-ALPS would reveal glymphatic dysfunction in idiopathic normal pressure hydrocephalus (iNPH) and whether the ALPS index was associated with disease severity. METHODS: Thirty iNPH patients (13 men; median age 77 years) and 27 healthy controls (10 men; median age 73 years) underwent MRI and clinical assessment with the Timed Up and Go test (TUG) and Mini-Mental State Examination (MMSE); only the patients were evaluated with the Hellström iNPH scale. MRI data were analyzed with the DTI-ALPS method and Radscale screening tool. RESULTS: iNPH patients showed significantly lower mean ALPS index scores compared with healthy controls (median [interquartile range] 1.09 [1.00-1.15] vs 1.49 [1.36-1.59], p < 0.001). Female healthy controls showed significantly higher ALPS index scores than males in both hemispheres (e.g., right hemisphere 1.62 [1.47-1.67] vs 1.33 [1.14-1.41], p = 0.001). This sex difference was not seen in iNPH patients. The authors found a moderate exponential correlation between mean ALPS index score and motor function as measured with time required to complete TUG (r = -0.644, p < 0.001), number of steps to complete TUG (r = -0.571, p < 0.001), 10-m walk time (r = -0.637, p < 0.001), and 10-m walk steps (r = -0.588, p < 0.001). The authors also found a positive linear correlation between mean ALPS index score and MMSE score (r = 0.416, p = 0.001). Simple linear regression showed a significant effect of diagnosis (B = -0.39, p < 0.001, R2 = 0.459), female sex (B = 0.232, p = 0.002, R2 = 0.157), and Evans index (B = -4.151, p < 0.001, R2 = 0.559) on ALPS index. Multiple linear regression, including diagnosis, sex, and Evans index score, showed a higher predictive value (R2 = 0.626) than analysis of each of these factors alone. CONCLUSIONS: The ALPS index, which was significantly decreased in iNPH patients, could serve as a marker of disease severity, both clinically and in terms of neuroimaging. However, it is important to consider the significant influence of biological sex and ventriculomegaly on the ALPS index, which raises the question of whether the ALPS index solely reflects glymphatic function or if it also encompasses other types of injury. Future studies are needed to address potential confounding factors and further validate the ALPS method.

Motor Efficacy of Subcutaneous DIZ102, Intravenous DIZ101 or Intestinal Levodopa/Carbidopa Infusion.

BACKGROUND: It has been suggested that carbidopa at high blood concentrations may counter the therapeutic effect of levodopa in Parkinson's disease by entering the brain and blocking central levodopa conversion to dopamine. We previously demonstrated equivalent plasma levodopa concentration in patients with Parkinson's disease during 16 h of (1) intravenous carbidopa/levodopa (DIZ101) infusion, (2) subcutaneous carbidopa/levodopa (DIZ102) infusion or (3) intestinal carbidopa/levodopa gel infusion. Plasma levels of carbidopa were however approximately four times higher with DIZ101 and DIZ102 than with LCIG, and higher than those usually observed with oral levodopa/carbidopa. OBJECTIVES: To investigate if high carbidopa blood concentrations obtained with parenteral levodopa/carbidopa (ratio 8:1) counter the effect of levodopa on motor symptoms. METHODS: Eighteen patients with advanced Parkinson's disease were administered DIZ101, DIZ102, and intestinal levodopa/carbidopa gel for 16 h on different days in randomized order. Video recordings of a subset of the motor examination in the Unified Parkinson's Disease Rating Scale (UPDRS) were evaluated by raters blinded for treatment and time. Motor function was also measured using a wrist-worn device monitoring bradykinesia, dyskinesia, and tremor (Parkinson KinetiGraph). RESULTS: There was no tendency for poorer levodopa effect with DIZ101 or DIZ102 as compared to LCIG. CONCLUSION: Although DIZ101 or DIZ102 causes approximately four times higher plasma carbidopa levels than LCIG, patients responded equally well to all treatments. The results do not indicate that high plasma carbidopa levels hamper the motor efficacy of levodopa.

Preoperative and postoperative 1H-MR spectroscopy changes in frontal deep white matter and the thalamus in idiopathic normal pressure hydrocephalus.

BACKGROUND: In a previous study we found significantly decreased N-acetyl aspartate (NAA) and total N-acetyl (tNA) groups in the thalamus of patients with idiopathic normal pressure hydrocephalus (iNPH) compared with healthy individuals (HI). No significant difference between the groups could be found in the frontal deep white matter (FDWM). OBJECTIVE: The primary aim of this study was to investigate if these metabolites in the thalamus were normalised after shunt surgery. The secondary aim was to investigate postoperative metabolic changes in FDWM. SUBJECTS AND METHODS: Fourteen patients with iNPH, mean age 74 years, and 15 HI, also mean age 74 years, were examined. Assessment of a motor score (MOSs) was performed before and after shunt surgery. Absolute quantitative (1)H-MR spectroscopy (1.5 T, volumes of interest 2.5-3 ml) was performed on the patients in the FDWM and in the thalamus, before and 3 months after shunt surgery, and also once on the HI. The following metabolites were analysed: tNA, NAA, total creatine, total choline (tCho), myo-inositol (mIns), glutamate and lactate concentrations. MRI volumetric calculations of the lateral ventricles were also performed. RESULTS: At 3 months postoperatively, we found no significant changes of tNA or NAA in the thalamus. In contrast, in the FDWM, there was a significant increase of tCho (p=0.01) and a borderline significant decrease of mIns (p=0.06). 12/14 patients were shunt responders (motor function). Median reduction of the lateral ventricle was 16%. A weak correlation between MOS and ventricular reduction was seen. CONCLUSIONS: Normalisation of thalamic tNA and NAA could not be detected postoperatively. The increased tCho and decreased mIns in the FDWM postoperatively might relate to clinical improvement.

Living conditions, lifestyle habits and health in the general population in spring 2020 and one year into the COVID-19 pandemic in Sweden - Results from two cross-sectional studies carried out in 2020 and 2021.

The aim of the study was to investigate mental and physical health as well as living conditions and lifestyle habits in the adult general population in spring 2020 and one year into the COVID-19 pandemic in Sweden comparing results from two cross-sectional studies carried out in February-May 2020 and 2021. The study population comprises 2,273 persons in 2020 and 2,216 persons in 2021 who responded to the national public health survey sent to random population samples in one county in Sweden. The age group was 16-84 years, and the response rates were 45% and 44%, respectively. Differences in living conditions (economic difficulties, social support and worrying about losing one's job), lifestyle habits (physical activity, daily smoking, sitting duration and alcohol use), and health (self-rated health, pain in shoulders or neck, sleeping difficulties, anxiety or worry, and obesity) between years 2020 and 2021 were analysed using multiple binary logistic regression in men and women, adjusting for age group and educational level. Very few statistically significant differences were observed between 2020 and 2021 regarding living conditions, lifestyle factors and health. The main finding was that the prevalence of anxiety and worry increased among women. Surveillance of the long-term public health consequences of the pandemic in the general population using robust data and methods, is important for planning and targeting preventive activities.

The SELMA study: a birth cohort study in Sweden following more than 2000 mother-child pairs.

BACKGROUND: This paper describes the background, aim and study design for the Swedish SELMA study that aimed to investigate the importance of early life exposure during pregnancy and infancy to environmental factors with a major focus on endocrine disrupting chemicals for multiple chronic diseases/disorders in offspring. METHODS: The cohort was established by recruiting women in the 10th week of pregnancy. Blood and urine from the pregnant women and the child and air and dust from home environment from pregnancy and infancy period have been collected. Questionnaires were used to collect information on life styles, socio-economic status, living conditions, diet and medical history. RESULTS: Of the 8394 reported pregnant women, 6658 were invited to participate in the study. Among the invited women, 2582 (39%) agreed to participate. Of the 4076 (61%) non-participants, 2091 women were invited to a non-respondent questionnaire in order to examine possible selection bias. We found a self-selection bias in the established cohort when compared with the non-participant group, e.g. participating families did smoke less (14% vs. 19%), had more frequent asthma and allergy symptoms in the family (58% vs. 38%), as well as higher education among the mothers (51% vs. 36%) and more often lived in single-family houses (67% vs. 60%). CONCLUSIONS: These findings indicate that the participating families do not fully represent the study population and thus, the exposure in this population. However, there is no obvious reason that this selection bias will have an impact on identification of environmental risk factors.

Physical Capacity and Activity in Patients With Idiopathic Normal Pressure Hydrocephalus.

Introduction: Most patients with idiopathic normal pressure hydrocephalus (iNPH) improve gait after surgery. However, knowledge on physical capacity and activity after shunt surgery is limited. One of the aims of this study was to evaluate the effect of shunt surgery in patients with iNPH on short-distance walking, functional exercise capacity, functional strength, and variables of activity and sleep, 3 and 6 months postoperatively. Another aim was to evaluate the effect of a physical exercise program. Additionally, we studied how changes in short-distance walking were correlated with functional exercise capacity and voluntary walking. Methods: In total, 127 patients were consecutively included and randomized to the exercise group (n = 62) or the control group (n = 65). Participants in the exercise group underwent the supervision of a 12-week exercise program. All patients were assessed before surgery, at 3 and 6 months postoperatively with the 10-m walk test (10MWT), the 6-min walk test (6MWT), 30-s chair stand test (30sCST), and with the actigraphic recordings of activity variables measured for a total of 24 h/day for at least 3 days. Results: All patients improved at 3 months postoperatively in the 10MWT (p < 0.001), 6MWT (p < 0.001), and 30sCST (p < 0.001). These results were maintained after 6 months. Actigraphic recordings for voluntary walking (steps per minute) were improved and nighttime sleep (%) increased after 6 months (p = 0.01, p = 0.04). There were no significant differences between the exercise group and the control group, except for the postoperative change in the proportion of daytime sleep after 3 months, which was slightly more reduced compared to baseline in the exercise group (p = 0.04). Changes after 3 months in the 10MWT and 6MWT were moderately correlated (ρ= -0.49, p = 0.01) whereas the correlation between the 10MWT and voluntary walking was weak (ρ = -0.34, p = 0.01). Conclusion: Shunt surgery improved short-distance walking, functional exercise capacity, functional strength, and voluntary walking. An exercise program did not affect these outcomes. Short-distance walking was weakly correlated with voluntary walking, indicating improved physical capacity does not directly translate to increased physical activity. Further research should address how interventions should be tailored to promote physical activity after shunt surgery. Trial Registration: clinicaltrials.gov, Id: NCT02659111.

The demography of idiopathic normal pressure hydrocephalus: data on 3000 consecutive, surgically treated patients and a systematic review of the literature.

OBJECTIVE: The objective of this study was to describe the demographic characteristics of patients with idiopathic normal pressure hydrocephalus (iNPH) through an analysis of 3000 consecutive, surgically treated Swedish patients and a systematic review of the literature. METHODS: Data on age, sex, comorbidities, diagnostic delay, initial symptoms, and severity of symptoms at diagnosis were extracted from the Swedish Hydrocephalus Quality Registry. In addition, a systematic PRISMA-based review of the literature published from database inception until August 2019 was performed using the PubMed, Cochrane, and Scopus databases on the basis of two concepts: normal pressure hydrocephalus and demography and their association with related terms. Of 1020 unique articles, 16 were eligible for study inclusion and were assessed for quality using the Newcastle-Ottawa Scale. Mean and weighted mean values were calculated. RESULTS: The mean patient age at the time of surgery was 74.4 years, 79% of patients were in their 70s, and 60% of the patients were men. Almost 50% of the patients had symptoms from four main domains (i.e., balance, gait, cognition, and urinary dysfunction) at disease onset. Patients aged < 60 years (2%) reported more headaches and fewer balance problems than those aged ≥ 60. Women were more impaired in function than men at the time of diagnosis. Dementia (Mini-Mental State Examination score < 25) was found in 47% of the patients. Men had more diabetes, heart disease, hypertension, and stroke than women, and comorbidity correlated with increased impairment. The incidence of surgery for iNPH was 20%-40% of the disease incidence according to survey and operation-based studies. CONCLUSIONS: Most iNPH patients undergo surgery in their 70s. Those aged < 60 years show slightly different symptomatology and probably present with a specific disease entity, indicating that the lower age limit for iNPH should be 60 years. iNPH patients have severe impairment preceded by a long diagnostic delay. Even though the included study designs differed, the systematic review showed that the disorder has a very low treatment incidence. The importance of diagnosing and treating iNPH is further emphasized by the fact that iNPH may account for a considerable part of all cases of dementia.

Presence of asymptomatic Peripheral Arterial Disease in combination with common risk factors elevates the cardiovascular risk Substantially.

Background and aims: This study evaluates the risks for adverse cardiovascular (CV) events in Asymptomatic Peripheral Arterial Disease (APAD) combined with different traditional CV risk factors. Methods: A population-based observational study of 8000 subjects, identified 559 subjects as having APAD through ankle-brachial index (ABI) measurements and questionnaires regarding limb symptoms. This cohort and subgroups classified by presence of different traditional CV risk factors at baseline were assessed for 10 years on CV outcome. The recorded endpoints were all-cause mortality, CV mortality and non-fatal CV events. Results: Before subdividing the APAD subjects, the CV mortality incidence was 28.5 deaths per 1000 person-years as compared to 8.7 deaths for references without APAD. For subjects with hypertension at baseline the CV mortality incidence was 35.4 when combined with APAD and 11.7 without. In women with hypertension but without other risk factors, presence of APAD increased the age-adjusted Hazard Ratio (HR) for fatal and non-fatal CV events by 1.86 [CI 1.54,2.24, p < 0.001]. Conclusions: ABI measurements should be considered an important indication for aggressive multifactorial risk factor reduction in populations with any other prevalent CV risk factor. In hypertension, diabetes mellitus and a smoking history, coexisting APAD contributes significantly to the increased age-adjusted CV risk.