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The aim of this study was to examine whether the presence of risk alleles of the norepinephrine transporter gene (SLC6A2) polymorphisms is associated with differences in regional cerebral blood flow (rCBF) measured by 99mTc-HMPAO single photon emission computerized tomography in a Korean sample of ADHD.
The present study included 24 children with ADHD (9.5±2.4 years), consisting of 20 boys and 4 girls, aged 6-16 years. We investigated the G1287A and -3081(A/T) polymorphisms of the SLC6A2. The rCBF was compared between the ADHD subjects with and without risk alleles at the G1287A polymorphism and at the -3081(A/T) polymorphism. Image analyses were performed with voxelwise t-statistics using SPM2.
1) The ADHD subjects with the A allele (risk allele) at the G1287A polymorphism showed reduced perfusion in the left middle frontal gyrus, left inferior parietal lobule, precuneus, right superior frontal gyrus, and right superior parietal lobule as compared with ADHD subjects without the A allele (p< 0.001).
2) The ADHD subjects with the A allele at the G1287A polymorphism showed increased perfusion in the right middle frontal gyrus, right middle temporal gyrus, right superior temporal gyrus, right fusiform gyrus, right precentral gyrus, and right anterior lobe of cerebellum as compared with ADHD subjects without the A allele (p< 0.001).
3) No significant perfusion differences were found between ADHD subjects with and without the T allele (risk allele) at the -3081(A/T) polymorphism.
Our findings suggest that the SLC6A2 G1287A polymorphism might exert differential effects on rCBF in children with ADHD.
A substantial body of evidence linking late-life depression and dementia is now available. However, precise estimates of the relative risk attributable to late-life depression assessed with specific screening instruments at specified thresholds have not been previously produced.
Summarise dementia risks associated with depression.
Conduct a systematic review of the literature to produce precise and specific risk estimates for all cause dementia, Alzheimer's disease (AD), and vascular dementia (VaD).
The PubMed, PsycInfo, and Cochrane databases were systematically searched. Studies assessing incident dementia using validated measures of clinical depression or depressive symptomatology from prospective population studies were selected. The most specific analyses were conducted using both continuous symptomatology ratings and categorical measures of clinical depression based on single instruments with defined cut-offs.
The literature search yielded 121,301 articles, of which 36 were eligible. Included studies provided a combined sample size of 66,532 individuals including 6593 dementia, 2797 AD, and 585 VaD cases. Random-effects summary estimates showed that the risk associated with depression did not differ by type of dementia. The most widely used instrument was the CES-D. A clinical threshold of 20 produced similar estimates for all-cause dementia (HR 1.83, 95% CI 0.95–3.52) and for AD (HR 1.97, 95% CI 0.96–4.04). Estimates based on other thresholds and continuous measures produced consistent results.
Reliable dementia risk estimates associated with late-life depression can be produced and do not differ between dementia types. Such estimates should be used in evidence-based medicine practice to assess individual risk and to inform policy on interventions to decrease risk in the population.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
To investigate the association between parity and the risk of incident dementia in women.
We pooled baseline and follow-up data for community-dwelling women aged 60 or older from six population-based, prospective cohort studies from four European and two Asian countries. We investigated the association between parity and incident dementia using Cox proportional hazards regression models adjusted for age, educational level, hypertension, diabetes mellitus and cohort, with additional analysis by dementia subtype (Alzheimer dementia (AD) and non-Alzheimer dementia (NAD)).
Of 9756 women dementia-free at baseline, 7010 completed one or more follow-up assessments. The mean follow-up duration was 5.4 ± 3.1 years and dementia developed in 550 participants. The number of parities was associated with the risk of incident dementia (hazard ratio (HR) = 1.07, 95% confidence interval (CI) = 1.02–1.13). Grand multiparity (five or more parities) increased the risk of dementia by 30% compared to 1–4 parities (HR = 1.30, 95% CI = 1.02–1.67). The risk of NAD increased by 12% for every parity (HR = 1.12, 95% CI = 1.02–1.23) and by 60% for grand multiparity (HR = 1.60, 95% CI = 1.00–2.55), but the risk of AD was not significantly associated with parity.
Grand multiparity is a significant risk factor for dementia in women. This may have particularly important implications for women in low and middle-income countries where the fertility rate and prevalence of grand multiparity are high.
We aimed to investigate the heterogeneity of seasonal suicide patterns among multiple geographically, demographically and socioeconomically diverse populations.
Weekly time-series data of suicide counts for 354 communities in 12 countries during 1986–2016 were analysed. Two-stage analysis was performed. In the first stage, a generalised linear model, including cyclic splines, was used to estimate seasonal patterns of suicide for each community. In the second stage, the community-specific seasonal patterns were combined for each country using meta-regression. In addition, the community-specific seasonal patterns were regressed onto community-level socioeconomic, demographic and environmental indicators using meta-regression.
We observed seasonal patterns in suicide, with the counts peaking in spring and declining to a trough in winter in most of the countries. However, the shape of seasonal patterns varied among countries from bimodal to unimodal seasonality. The amplitude of seasonal patterns (i.e. the peak/trough relative risk) also varied from 1.47 (95% confidence interval [CI]: 1.33–1.62) to 1.05 (95% CI: 1.01–1.1) among 12 countries. The subgroup difference in the seasonal pattern also varied over countries. In some countries, larger amplitude was shown for females and for the elderly population (≥65 years of age) than for males and for younger people, respectively. The subperiod difference also varied; some countries showed increasing seasonality while others showed a decrease or little change. Finally, the amplitude was larger for communities with colder climates, higher proportions of elderly people and lower unemployment rates (p-values < 0.05).
Despite the common features of a spring peak and a winter trough, seasonal suicide patterns were largely heterogeneous in shape, amplitude, subgroup differences and temporal changes among different populations, as influenced by climate, demographic and socioeconomic conditions. Our findings may help elucidate the underlying mechanisms of seasonal suicide patterns and aid in improving the design of population-specific suicide prevention programmes based on these patterns.
Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
Intake of the plant-derived n-3 fatty acid α-linolenic acid (ALA) has been associated with anti-atherosclerotic properties. However, information on the association between ALA intake and development of peripheral artery disease (PAD) is lacking. In this follow-up study, we investigated the association between dietary intake of ALA and the rate of PAD among middle-aged Danish men and women enrolled into the Danish Diet, Cancer and Health cohort between 1993 and 1997. Incident PAD cases were identified through the Danish National Patient Register. Intake of ALA was assessed using a validated FFQ. Statistical analyses were performed using Cox proportional hazard regression allowing for separate baseline hazards among sexes and adjusted for established risk factors for PAD. During a median of 13·6 years of follow-up, we identified 950 valid cases of PAD with complete information on covariates. The median energy-adjusted ALA intake within the cohort was 1·76 g/d (95 % central range: 0·94–3·28). In multivariable analyses, we found no statistically significant association between intake of ALA and the rate of PAD (P = 0·339). Also, no statistically significant associations were observed in analyses including additional adjustment for co-morbidities and in sex-specific analyses. In supplemental analyses with additional adjustment for potential dietary risk factors, we found a weak inverse association of PAD with ALA intake above the median, but the association was not statistically significant (P = 0·314). In conclusion, dietary intake of ALA was not consistently associated with decreased risk of PAD.
There are no definite guidelines regarding the most adequate steroid regimens for acute acoustic trauma.
To elucidate the dose-dependent differing benefits of oral steroids on hearing improvement following acute acoustic trauma.
Twenty-nine patients treated with oral steroids following a diagnosis of unilateral acute acoustic trauma were retrospectively reviewed. Patients were sorted into two groups with an oral steroid regimen. Group 1 received a 14-day course of treatment: 60 mg prednisolone daily for 10 days, tapering off over days 11–14. Group 2 received prednisolone for a total of 10 days: 60 mg for 5 days, tapering down each day for the remainder. Multivariable linear regression analysis was performed to evaluate the factors associated with the hearing gain.
In the multivariable regression (R2 = 0.51, p < 0.001), patients in group 1 showed more significant improvement in the degree of hearing gain compared to group 2 (p = 0.03).
After comparing the differing benefits of oral steroids on hearing improvement by dosage, we recommend a high dose of prednisolone (60 mg per day) for 10 days, tapering over the remaining 4 days, for better hearing recovery following acute acoustic trauma.
Background: Canadian Stroke Guidelines recommend that Transient Ischemic Attack (TIA) patients at highest risk of stroke recurrence should undergo immediate vascular imaging. Computed tomography angiography (CTA) of the head and neck is recommended over carotid doppler because it allows for enhanced visualization of the intracranial and posterior circulation vasculature. Imaging while patients are in the emergency department (ED) is optimal for high-risk patients because the risk of stroke recurrence is highest in the first 48 hours. Aim Statement: At our hospital, a designated stroke centre, less than 5% of TIA patients meet national recommendations by undergoing CTA in the ED. We sought to increase the rate of CTA in high risk ED TIA patients from less than 5% to at least 80% in 10 months. Measures & Design: We used a multi-faceted approach to improve our adherence to guidelines including: 1) education for staff ED physicians; 2) agreements between ED and radiology to facilitate rapid access to CTA; 3) agreements between ED and neurology for consultations regarding patients with abnormal CTA; and 4) the creation of an electronic decision support tool to guide ED physicians as to which patients require CTA. We measured the rate of CTA in high risk patients biweekly using retrospective chart review of patients referred to the TIA clinic from the ED on a biweekly basis. As a balancing measure, we also measured the rate of CTA in non-high risk patients. Evaluation/Results: Data collection is ongoing. An interim run chart at 19 weeks shows a complete shift above the median after implementation, with CTA rates between 70 and 100%. At the time of submission, we had no downward trends below 80%, showing sustained improvement. The CTA rate in non-high risk patients did also increase. Disucssion/Impact: After 19 weeks of our intervention, 112 (78.9%) of high risk TIA patients had a CTA, compared to 10 (9.8%) in the 19 weeks prior to our intervention. On average, 10-15% of high risk patients will have an identifiable lesion on CTA, leading to immediate change in management (at minimum, an inpatient consultation with neurology). Our multi-faceted approach could be replicated in any ED with the engagement and availability of the same multi-disciplinary team (ED, radiology, and neurology), access to CTA, and electronic orders.
Different diagnostic interviews are used as reference standards for major depression classification in research. Semi-structured interviews involve clinical judgement, whereas fully structured interviews are completely scripted. The Mini International Neuropsychiatric Interview (MINI), a brief fully structured interview, is also sometimes used. It is not known whether interview method is associated with probability of major depression classification.
To evaluate the association between interview method and odds of major depression classification, controlling for depressive symptom scores and participant characteristics.
Data collected for an individual participant data meta-analysis of Patient Health Questionnaire-9 (PHQ-9) diagnostic accuracy were analysed and binomial generalised linear mixed models were fit.
A total of 17 158 participants (2287 with major depression) from 57 primary studies were analysed. Among fully structured interviews, odds of major depression were higher for the MINI compared with the Composite International Diagnostic Interview (CIDI) (odds ratio (OR) = 2.10; 95% CI = 1.15–3.87). Compared with semi-structured interviews, fully structured interviews (MINI excluded) were non-significantly more likely to classify participants with low-level depressive symptoms (PHQ-9 scores ≤6) as having major depression (OR = 3.13; 95% CI = 0.98–10.00), similarly likely for moderate-level symptoms (PHQ-9 scores 7–15) (OR = 0.96; 95% CI = 0.56–1.66) and significantly less likely for high-level symptoms (PHQ-9 scores ≥16) (OR = 0.50; 95% CI = 0.26–0.97).
The MINI may identify more people as depressed than the CIDI, and semi-structured and fully structured interviews may not be interchangeable methods, but these results should be replicated.
Declaration of interest
Drs Jetté and Patten declare that they received a grant, outside the submitted work, from the Hotchkiss Brain Institute, which was jointly funded by the Institute and Pfizer. Pfizer was the original sponsor of the development of the PHQ-9, which is now in the public domain. Dr Chan is a steering committee member or consultant of Astra Zeneca, Bayer, Lilly, MSD and Pfizer. She has received sponsorships and honorarium for giving lectures and providing consultancy and her affiliated institution has received research grants from these companies. Dr Hegerl declares that within the past 3 years, he was an advisory board member for Lundbeck, Servier and Otsuka Pharma; a consultant for Bayer Pharma; and a speaker for Medice Arzneimittel, Novartis, and Roche Pharma, all outside the submitted work. Dr Inagaki declares that he has received grants from Novartis Pharma, lecture fees from Pfizer, Mochida, Shionogi, Sumitomo Dainippon Pharma, Daiichi-Sankyo, Meiji Seika and Takeda, and royalties from Nippon Hyoron Sha, Nanzando, Seiwa Shoten, Igaku-shoin and Technomics, all outside of the submitted work. Dr Yamada reports personal fees from Meiji Seika Pharma Co., Ltd., MSD K.K., Asahi Kasei Pharma Corporation, Seishin Shobo, Seiwa Shoten Co., Ltd., Igaku-shoin Ltd., Chugai Igakusha and Sentan Igakusha, all outside the submitted work. All other authors declare no competing interests. No funder had any role in the design and conduct of the study; collection, management, analysis and interpretation of the data; preparation, review or approval of the manuscript; and decision to submit the manuscript for publication.
Introduction: Foreign patients often do not receive appropriate treatment in the emergency room as compared to locals. This is due to various causes such as language, insurance, and cultural differences. The purpose of this study was to investigate whether there is a wide range of health inequalities among foreigners who visited the emergency room with injury and to find out what causes it. Methods: We analyzed clinical data from the National Emergency Department Information System(NEDIS) database, which visited the emergency room from January 1, 2013 to December 31, 2015, in all age groups. Foreigners are classified based on the personal information described in the NEDIS. We analyzed the number of injuries, serious cases(death, operation, ICU admission), length of stay in ER, and transfer ratio. Results: A total of 4,464,603 cases of injured patients were included, of whom 67,683 were foreign patients. The incidence rate per 100,000 people per year was 2960.5 from locals and 1659.8 from foreigners. Serious outcomes were higher for foreigners than for locals(31.0% versus 23.2%, p<0.001). There was a further difference in the rural region. Length of stay was longer for foreigners(72 versus 69 minutes, median, p<0.001). The transfer rate was also higher for foreigners(1.9% versus 1.6%, p<0.001). Daegu had the highest ratio of foreigners’ injury compared to locals(ratio=0.998). Jeonnam(0.073) was the highest serious outcome rate in Korea, and Jeonbuk(0.070) was the second. The area with the longest length of stay in the Emergency department was the median 139 minutes for locals and 153 minutes for foreigners in Daegu. The more patients per day, the shorter the time spent in the emergency rooms(Spearman correlation coefficient=-0.388). This phenomenon was more prominent in locals(-0.624 versus -0.175). Multivariable logistic regression was used as a dependent variable for the serious outcomes of foreign patients. The foreign patients(OR=1.413, p<0.001), intention, no insurance, age, sex, urban area, low blood pressure, decreased consciousness, transfer, acuity, and length of stay were statistically significant. Conclusion: This study showed that there is a health inequality for foreigners who came to the emergency room due to injury in Korea. Also, serious outcomes from injury in foreigners have been shown to be related to various causes including factors of the foreigner.
Coinfection with human immunodeficiency virus (HIV) and viral hepatitis is associated with high morbidity and mortality in the absence of clinical management, making identification of these cases crucial. We examined characteristics of HIV and viral hepatitis coinfections by using surveillance data from 15 US states and two cities. Each jurisdiction used an automated deterministic matching method to link surveillance data for persons with reported acute and chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections, to persons reported with HIV infection. Of the 504 398 persons living with diagnosed HIV infection at the end of 2014, 2.0% were coinfected with HBV and 6.7% were coinfected with HCV. Of the 269 884 persons ever reported with HBV, 5.2% were reported with HIV. Of the 1 093 050 persons ever reported with HCV, 4.3% were reported with HIV. A greater proportion of persons coinfected with HIV and HBV were males and blacks/African Americans, compared with those with HIV monoinfection. Persons who inject drugs represented a greater proportion of those coinfected with HIV and HCV, compared with those with HIV monoinfection. Matching HIV and viral hepatitis surveillance data highlights epidemiological characteristics of persons coinfected and can be used to routinely monitor health status and guide state and national public health interventions.
Impulsive solar energetic particle (SEP) events originate from the energy dissipation process in small solar flares. Anomalous abundances in impulsive SEP events provide an evidence on unique, yet unclear, acceleration mechanism. The pattern of heavy-ion enhancements indicates that the temperature of the source plasma that is accelerated is low and not flare-like. We examine the solar source of the 3He-rich SEP event of 2012 November 20 using Solar Dynamics Observatory (SDO)/ Atmospheric Imaging Assembly (AIA) images and investigate its thermal variation. The examined event is associated with recurrent coronal jets. The Differential Emission Measure (DEM) analysis is applied to study the temperature evolution/distribution of the source regions. Preliminary results show that the temperature of the associated solar source is ranged between 1.2-3.1 MK.
Introduction: Emergency department (ED) access block is the #1 safety concern in Canadian EDs. Its main cause is hospital access block, manifested by prolonged boarding of inpatients in EDs. Hospital administrators often believe this problem is too big to be solved and would require large increases in hospital capacity. Our objective was to quantify ED access gap by estimating the cumulative hours that CTAS 1-3 patients are blocked in waiting areas. This value, expressed as a proportion of inpatient care capacity, is an estimate of the bed hours a hospital would have to find in order to resolve ED access. Methods: A convenience sample of urban Canadian ED directors were asked to provide data summarizing their CTAS 1-3 inflow, the proportion triaged to nursed stretchers vs. RAZ or Intake areas, and time to care space. Total ED access gap was calculated by multiplying the number of CTAS 1-3 patients by their average delay to care space. Time to stretcher was captured electronically at participating sites, but time to RAZ or intake spaces was often not. In such cases, respondents provided time from triage to first RN or MD assessment in these areas. The primary outcome was total annual ED access block hours for emergent-urgent patients, expressed as a proportion of funded inpatient bed hours. Results: Directors of 40 EDs were queried. Six sites did not gather the data elements required. Of 34 remaining, 29 (85.3%) provided data, including 15 tertiary (T), 10 community (C) and 2 pediatric (P) sites in 12 cities. Mean census for the 3 ED types was 72,308 (T), 58,849 C) and 61,050 (P) visits per year. CTAS 1-3 patients accounted for 73.4% (T), 67.7% (C) and 66.2% (P) of visits in the 3 groups, and 34% (T), 46% (C) and 44% (P) of these patients were treated in RAZ or intake areas rather than staffed ED stretchers. Mean time to stretcher/RAZ care was 50/71 min (T), 46/62 min (C), and 37/59 min (P). Average ED access gap was 47,564 hrs (T), 37,222 hrs (C) and 35,407 hrs (P), while average inpatient bed capacity was 599 beds (5,243,486 hrs), 291 beds (2,545,875 hrs) and 150 beds (1,314,000 hrs) respectively. ED access gap as a proportion of inpatient care capacity was 0.93% for tertiary, 1.46% for community and 2.69% for pediatric centres. Conclusion: ED access gap is very large in Canadian EDs, but small compared to hospital operating capacity. Hospital capacity or efficiency improvements in the range of 1-3% could profoundly mitigate ED access block.
Universal screening for postpartum depression is recommended in many countries. Knowledge of whether the disclosure of depressive symptoms in the postpartum period differs across cultures could improve detection and provide new insights into the pathogenesis. Moreover, it is a necessary step to evaluate the universal use of screening instruments in research and clinical practice. In the current study we sought to assess whether the Edinburgh Postnatal Depression Scale (EPDS), the most widely used screening tool for postpartum depression, measures the same underlying construct across cultural groups in a large international dataset.
Ordinal regression and measurement invariance were used to explore the association between culture, operationalized as education, ethnicity/race and continent, and endorsement of depressive symptoms using the EPDS on 8209 new mothers from Europe and the USA.
Education, but not ethnicity/race, influenced the reporting of postpartum depression [difference between robust comparative fit indexes (∆*CFI) < 0.01]. The structure of EPDS responses significantly differed between Europe and the USA (∆*CFI > 0.01), but not between European countries (∆*CFI < 0.01).
Investigators and clinicians should be aware of the potential differences in expression of phenotype of postpartum depression that women of different educational backgrounds may manifest. The increasing cultural heterogeneity of societies together with the tendency towards globalization requires a culturally sensitive approach to patients, research and policies, that takes into account, beyond rhetoric, the context of a person's experiences and the context in which the research is conducted.
The Antarctic Roadmap Challenges (ARC) project identified critical requirements to deliver high priority Antarctic research in the 21st century. The ARC project addressed the challenges of enabling technologies, facilitating access, providing logistics and infrastructure, and capitalizing on international co-operation. Technological requirements include: i) innovative automated in situ observing systems, sensors and interoperable platforms (including power demands), ii) realistic and holistic numerical models, iii) enhanced remote sensing and sensors, iv) expanded sample collection and retrieval technologies, and v) greater cyber-infrastructure to process ‘big data’ collection, transmission and analyses while promoting data accessibility. These technologies must be widely available, performance and reliability must be improved and technologies used elsewhere must be applied to the Antarctic. Considerable Antarctic research is field-based, making access to vital geographical targets essential. Future research will require continent- and ocean-wide environmentally responsible access to coastal and interior Antarctica and the Southern Ocean. Year-round access is indispensable. The cost of future Antarctic science is great but there are opportunities for all to participate commensurate with national resources, expertise and interests. The scope of future Antarctic research will necessitate enhanced and inventive interdisciplinary and international collaborations. The full promise of Antarctic science will only be realized if nations act together.
A new approach is proposed to analyze Bremsstrahlung X-rays that are emitted from laser-produced plasmas (LPP) and are measured by a stack type spectrometer. This new method is based on a spectral tomographic reconstruction concept with the variational principle for optimization, without referring to the electron energy distribution of a plasma. This approach is applied to the analysis of some experimental data obtained at a few major laser facilities to demonstrate the applicability of the method. Slope temperatures of X-rays from LPP are determined with a two-temperature model, showing different spectral characteristics of X-rays depending on laser properties used in the experiments.
Obsessive-compulsive disorder (OCD) is a chronic, relapsing mental illness. Selective serotonin reuptake inhibitors block serotonin transporters (SERTs) and are the mainstay of treatment for OCD. SERT abnormalities are reported in drug-free patients with OCD, but it is not known what happens to SERT levels during treatment. This is important as alterations in SERT levels in patients under treatment could underlie poor response, or relapse during or after treatment. The aim of the present study was first to validate a novel approach to measuring SERT levels in people taking treatment and then to investigate SERT binding potential (BP) using [11C]DASB PET in patients with OCD currently treated with escitalopram in comparison with healthy controls.
Twelve patients and age- and sex-matched healthy controls were enrolled. The patients and healthy controls underwent serial PET scans after administration of escitalopram and blood samples for drug concentrations were collected simultaneously with the scans. Drug-free BPs were obtained by using an inhibitory Emax model we developed previously.
The inhibitory Emax model was able to accurately predict drug-free SERT BP in people taking drug treatment. The drug-free BP in patients with OCD currently treated with escitalopram was significantly different from those in healthy volunteers [Cohen's d = 0.03 (caudate), 1.16 (putamen), 1.46 (thalamus), −5.67 (dorsal raphe nucleus)].
This result extends previous findings showing SERT abnormalities in drug-free patients with OCD by indicating that altered SERT availability is seen in OCD despite treatment. This could account for poor response and the high risk of relapse in OCD.