Epilepsy as a Network Disorder (1): What can we learn from other network disorders such as autistic spectrum disorder and mood disorders?

Epilepsy is a neurologic condition which often occurs with other neurologic and psychiatric disorders. The relation between epilepsy and these conditions is complex. Some population-based studies have identified a bidirectional relation, whereby not only patients with epilepsy are at increased risk of suffering from some of these neurologic and psychiatric disorders (migraine, stroke, dementia, autism, depression, anxiety disorders, Attention deficit hyperactivity disorder (ADHD), and psychosis), but also patients with these conditions are at increased risk of suffering from epilepsy. The existence of common pathogenic mechanisms has been postulated as a potential explanation of this phenomenon. To reassess the relationships between neurological and psychiatric conditions in general, and specifically autism, depression, Alzheimer's disease, schizophrenia, and epilepsy, a recent meeting brought together basic researchers and clinician scientists entitled "Epilepsy as a Network Disorder." This was the fourth in a series of conferences, the "Fourth International Halifax Conference and Retreat". This manuscript summarizes the proceedings on potential relations between Epilepsy on the one hand and autism and depression on the other. A companion manuscript provides a summary of the proceedings about the relation between epilepsy and Alzheimer's disease and schizophrenia, closed by the role of translational research in clarifying these relationships. The review of the topics in these two manuscripts will provide a better understanding of the mechanisms operant in some of the common neurologic and psychiatric comorbidities of epilepsy.

Clinical Complexity and Use of Antipsychotics and Restraints in Long-Term Care Residents with Parkinson's Disease

BACKGROUND

Patients with Parkinson's disease (PD) and/or Parkinsonism are affected by a complex burden of comorbidity. Many ultimately require institutional care, where they may be subject to the application of physical restraints or the prescription of antipsychotic medications, making them more vulnerable to adverse outcomes.

OBJECTIVES

The objectives of this paper are to: 1) describe the clinical complexity of older institutionalized persons with PD; and 2) examine patterns and predictors of restraint use and prescription of antipsychotics in this population.

METHODS

Population-based cross-sectional cohort study. Residents with PD and/or Parkinsonism living in long-term care (LTC) facilities in 6 Canadian provinces and 1 Northern Territory and Complex Continuing Care (CCC) facilities in Manitoba and Ontario, Canada. The RAI MDS 2.0 instrument was used to assess all LTC residents and CCC residents. Clinical characteristics and the prevalence of major comorbidities were examined. Multivariate modeling was used to identify the characteristics of PD residents most associated with the prescription of antipsychotics and the use of restraints in LTC and CCC facilities.

RESULTS

Residents with PD in LTC and CCC exhibit a high prevalence of dementia, major psychiatric disorders, stroke, heart failure, chronic obstructive pulmonary disease and diabetes mellitus. More than 90% of LTC and CCC residents with PD had cognitive impairment; with more than half having moderate to severe impairment. Residents with PD were more likely to receive antipsychotics than those without PD. Antipsychotic use was associated with psychosis and aggressive behaviours, but also with unsteady gait and higher comorbidity and medication count. Similarly, although more common in CCC than LTC facilities, both psychosis and aggressive behaviours were associated with restraint use, as was greater cognitive and functional impairment, and urinary incontinence. Younger age, male gender, and lower physician access were all associated with greater antipsychotic and restraint use.

CONCLUSIONS

LTC and CCC residents with PD are very complex medically. Use of antipsychotics and restraints is common, and their use is often associated with factors other than psychosis or aggression.

Serotonin reuptake inhibitors and mortality in epilepsy: A linked primary-care cohort study

OBJECTIVE

Preliminary evidence suggests that serotonin reuptake inhibitor (SRI) use may increase postictal respiratory drive and prevent death. We sought to determine whether SRIs are associated with improved all-cause and possible seizure-specific mortality in patients with epilepsy.

METHODS

Patients with epilepsy and a random 10:1 sample without epilepsy were extracted from The ClinicAl research using LInked Bespoke studies and Electronic health Records (CALIBER) resource. The hazard ratio (HR) of all-cause and possible seizure-specific mortality, treating SRI use as a time-varying covariate, was determined using the date of a second SRI prescription as exposure and in discrete 6-month periods over the entire duration of follow-up. We used Cox regression and competing risk models with Firth correction to calculate the HR. We controlled for age, sex, depression, comorbidity, (Charlson comorbidity index) and socioeconomic status (Index of Multiple Deprivation).

RESULTS

We identified 2,718,952 eligible patients in CALIBER, of whom 16,379 (0.60%) had epilepsy. Median age and follow-up were 44 (interquartile range [IQR] 29-61]) and 6.4 years (IQR 2.4-10.4 years), respectively, and 53% were female. A total of 2,178 patients (13%) had at least two SRI prescriptions. Hazard of all-cause mortality was significantly elevated following a second prescription for an SRI (HR 1.64 95% confidence interval [95% CI] 1.44-1.86; p < 0.001). The HR was similar in 163,778 age, sex, and general practitioner (GP) practice-matched controls without epilepsy. Exposure to an SRI was not associated with seizure-related death (HR 1.08, 95% CI 0.59-1.97; 0.796).

SIGNIFICANCE

There is no evidence in this large population-based cohort that SRIs protect against all-cause mortality or seizure-specific mortality. Rather, SRI use was associated with increased mortality, irrespective of epilepsy, which is probably due to various factors associated with the use of antidepressants. Larger studies with systematically collected clinical data are needed to shed further light on these findings.

Association of Depression and Treated Depression With Epilepsy and Seizure Outcomes: A Multicohort Analysis

Importance

A bidirectional relationship exists between epilepsy and depression. However, any putative biological gradient between depression severity and the risk of epilepsy, and the degree to which depression mediates the influence of independent risk factors for epilepsy, has yet to be examined.

Objective

To determine the effect of depression on the risk of epilepsy and seizure outcomes.

Design, Setting, and Participants

An observational study of a population-based primary care cohort (all patients free of prevalent depression and epilepsy at 18-90 years of age who were active after the Acceptable Mortality Reporting date in The Health Improvement Network database) and a prospectively collected tertiary care cohort (all patients whose data were prospectively collected from the Calgary Comprehensive Epilepsy Programme). The analyses were performed on March 16, 2016.

Main Outcome and Measures

The hazard of developing epilepsy after incident depression and vice versa was calculated. In addition, a mediation analysis of the effect of depression on risk factors for epilepsy and the odds of seizure freedom stratified by the presence of depression were performed.

Results

We identified 10 595 709 patients in The Health Improvement Network of whom 229 164 (2.2%) developed depression and 97 177 (0.9%) developed epilepsy. The median age was 44 years (interquartile range, 32-58 years) for those with depression and 56 years (interquartile range, 43-71 years) for those with epilepsy. Significantly more patients with depression (144 373 [63%] were women, and 84 791 [37%] were men; P < .001) or epilepsy (54 419 [56%] were women, and 42 758 [44%] were men; P < .001) were female. Incident epilepsy was associated with an increased hazard of developing depression (hazard ratio [HR], 2.04 [95% CI, 1.97-2.09]; P < .001), and incident depression was associated with an increased hazard of developing epilepsy (HR, 2.55 [95% CI, 2.49-2.60]; P < .001) There was an incremental hazard according to depression treatment type with lowest risk for those receiving counselling alone (HR, 1.84 [95% CI, 1.30-2.59]; P < .001), an intermediate risk for those receiving antidepressants alone (HR, 3.43 [95% CI, 3.37-3.47]; P < .001), and the highest risk for those receiving both (HR, 9.85 [95% CI, 5.74-16.90]; P < .001). Furthermore, depression mediated the relationship between sex, social deprivation, and Charlson Comorbidity Index with incident epilepsy, accounting for 4.6%, 7.1%, and 20.6% of the total effects of these explanatory variables, respectively. In the Comprehensive Epilepsy Programme, the odds of failing to achieve 1-year seizure freedom were significantly higher for those with depression or treated depression.

Conclusions and Relevance

Common underlying pathophysiological mechanisms may explain the risk of developing epilepsy following incident depression. Treated depression is associated with worse epilepsy outcomes, suggesting that this may be a surrogate for more severe depression and that severity of depression is associated with severity of epilepsy.

ACSC Indicator: testing reliability for hypertension

BACKGROUND

With high-quality community-based primary care, hospitalizations for ambulatory care sensitive conditions (ACSC) are considered avoidable. The purpose of this study was to test the inter-physician reliability of judgments of avoidable hospitalizations for one ACSC, uncomplicated hypertension, derived from medical chart review.

METHODS

We applied the Canadian Institute for Health Information's case definition to obtain a random sample of patients who had an ACSC hospitalization for uncomplicated hypertension in Calgary, Alberta. Medical chart review was conducted by three experienced internal medicine specialists. Implicit methods were used to judge avoidability of hospitalization using a validated 5-point scale.

RESULTS

There was poor agreement among three physicians raters when judging the avoidability of 82 ACSC hospitalizations for uncomplicated hypertension (κ = 0.092). The κ also remained low when assessing agreement between raters 1 and 3 (κ = 0.092), but the κ was lower (less than chance agreement) for raters 1 and 2 (κ = -0.119) and raters 2 and 3 (κ = -0.008). When the 5-point scale was dichotomized, there was fair agreement among three raters (κ = 0.217). The proportion of ACSC hospitalizations for uncomplicated hypertension that were rated as avoidable was 32.9%, 6.1% and 26.8% for raters 1, 2, and 3, respectively.

CONCLUSIONS

This study found a low proportion of ACSC hospitalization were rated as avoidable, with poor to fair agreement of judgment between physician raters. This suggests that the validity and utility of this health indicator is questionable. It points to a need to abandon the use of ACSC entirely; or alternatively to work on the development of explicit criteria for judging avoidability of hospitalization for ACSC such as hypertension.

Hospital safety among neurologic patients

Objective:

To examine the frequency and type of adverse events (AEs) experienced by neurologic patients in hospital.

Methods:

This population-based, retrospective cohort study used hospital discharge abstract data for children and adults admitted to hospital from 2009 to 2015 with 1 of 9 neurologic conditions (Alzheimer disease and related dementia, brain tumor, epilepsy, motor neuron disease, multiple sclerosis, parkinsonism/Parkinson disease, spinal cord injury, traumatic brain injury, and stroke). Neurologic conditions were identified with ICD-10-CA codes. Eighteen AEs were examined with ICD-10-CA codes. The proportion of AEs was calculated, and regression analysis was used to examine factors and outcomes associated with AEs (age, sex, comorbidity, length of stay, and mortality).

Results:

The overall proportion of admissions associated with an AE among those with a neurologic condition was 11 per 100 admissions. Those with a spinal cord injury had the highest proportion of AEs (39.4 per 100 admissions). The most common AEs were infections and respiratory complications (32.0% and 16.7%, respectively). Age and the presence of comorbidities were associated with higher odds of an AE, while readmission was associated with lower odds of an AE. Having an AE was associated with increased length of stay and higher odds of mortality.

Conclusions:

This study demonstrates that neurologic patients have a high proportion of AEs in hospital. The findings provide information on the quality and safety of care for people with neurologic conditions in hospital, which can help inform future quality improvement initiatives.

Anticoagulant and antiplatelet use in seniors with chronic subdural hematoma

Objective:

To address whether to restart older patients on anticoagulants or antiplatelet agents in the setting of a chronic subdural hematoma (cSDH).

Methods:

This is an update of a previous review (searched until July 2012). Medline, EMBASE, ISI Web of Knowledge, Google Scholar, PLOS, and the Cochrane Register for Systematic Reviews databases were searched from January 2012 to December 2016. Studies included older adults (those over 65 years) experiencing traumatic subdural hematoma or cSDH who were on anticoagulation or antiplatelet agents.

Results:

Seven studies were included (mean age 72 years). Four out of 7 studies provided combined data on anticoagulants or antiplatelet use. Only one study found anticoagulant or antiplatelet agent use to be a significant factor for cSDH rebleeding. Two studies considered anticoagulant use only and both reported similar increased odds of rebleeding (odds ratio [OR] 1.75, 95% confidence interval [CI] 0.18–16.86; OR 2.7 95% CI 1.42–6.96). Antiplatelets were not found to be associated with rebleeding. Ideal timing to resume anticoagulants or antiplatelets was unclear.

Conclusions:

Anticoagulant medication was associated with increased rebleeding risk in older adults with cSDH. However, antiplatelet medication was not associated with increased risk of rebleeding.

The impact of seizures on epilepsy outcomes: A national, community-based survey

OBJECTIVE

The aim of this study was to examine the impact of seizures on persons living with epilepsy in a national, community-based setting.

METHODS

The data source was the Survey of Living with Neurological Conditions in Canada (SLNCC), a cohort derived from a national population-based survey of noninstitutionalized persons aged 15 or more years. Participants had to be on a seizure drug or to have had a seizure in the past 5 years to meet the definition of active epilepsy. The respondents were further stratified by seizure status: the seizure group experienced ≥1 seizure in the past 5 years versus the no seizure group who were seizure-free in the past ≥5 years regardless of medication status. Weighted overall and stratified prevalence estimates and odds ratios were used to estimate associations.

RESULTS

The SLNCC included 713 persons with epilepsy with a mean age of 45.4 (standard deviation 18.0) years. Fewer people in the seizure group (42.7%) reported being much better than a year ago versus those in the no seizure group (70.1%). Of those with seizures, 32.1% (95% confidence interval [95% CI] 18.8-45.3) had symptoms suggestive of major depression (as per the Patient Health Questionnaire-9) compared to 7.7% (95% CI 3.4-11.9) of those without seizures. Driving, educational, and work opportunities were also significantly limited, whereas stigma was significantly greater in those with seizures.

SIGNIFICANCE

This community-based study emphasizes the need for seizure freedom to improve clinical and psychosocial outcomes in persons with epilepsy. Seizure freedom has an important influence on overall health, as those with at least one seizure over the prior 5 years had an increased risk of mood disorders, worse quality of life, and faced significantly more stigma.

Guidelines for dementia or Parkinson's disease with depression or anxiety: a systematic review

BACKGROUND

Depression and anxiety remain under-diagnosed and under-treated in those with neurologic diseases such as dementia or Parkinson's Disease (PD). Our objectives were to first, to provide a synthesis of high quality guidelines available for the identification and management of depression or anxiety in those with dementia or PD. Second, to identify areas for improvement for future guidelines.

METHODS

We searched MEDLINE, PsycINFO, and EMBASE (2009 to July 24, 2015), grey literature (83 sources; July 24-Sept 6, 2015), and bibliographies of included studies. Included studies were evaluated for quality by four independent reviewers the AGREE II tool. Guideline characteristics, statements and recommendations relevant to depression or anxiety for dementia and PD were then extracted. (PROSPERO CRD: 42016014584) RESULTS: 8121 citations were reviewed with 31 full text articles included for assessment with the AGREE II tool. 17 were of sufficient quality for inclusion. Mean overall quality scores were between 4.25 to 6.5. Domain scores were lowest in the areas of stakeholder involvement, applicability, and editorial independence. Recommendations for the screening and diagnosis of depression were found for PD and dementia. There was little evidence to guide diagnosis or management of anxiety. Non-pharmacologic therapies were recommended for dementia patients. Most advocated pharmacologic treatment for depression, for both PD and dementia, but did not specify an agent due to lack of evidence.

CONCLUSIONS

The available recent high quality guidelines outline several recommendations for the management of comorbid depression or anxiety in PD or dementia. However there remain significant gaps in the evidence.

The International Incidence of Traumatic Brain Injury: A Systematic Review and Meta-Analysis

BACKGROUND

Understanding the epidemiology of traumatic brain injury (TBI) is essential to shape public health policy, implement prevention strategies, and justify allocation of resources toward research, education, and rehabilitation in TBI. There is not, to our knowledge, a systematic review of population-based studies addressing the epidemiology of TBI that includes all subtypes. We performed a comprehensive systematic review and meta-analysis of the worldwide incidence of TBI.

METHODS

A search was conducted on May 23, 2014, in Medline and EMBASE according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Abstracts were screened independently and in duplicate to identify original research. Study quality and ascertainment bias were assessed in duplicate using a previously published tool. Demographic data and incidence estimates from each study were recorded, along with stratification by age, gender, year of data collection, and severity.

RESULTS

The search strategy yielded 4944 citations. Two hundred and sixteen articles met criteria for full-text review; 144 were excluded. Hand searching resulted in ten additional articles. Eighty-two studies met all eligibility criteria. The pooled annual incidence proportion for all ages was 295 per 100,000 (95% confidence interval: 274-317). The pooled incidence rate for all ages was 349 (95% confidence interval: 96.2-1266) per 100,000 person-years. Incidence proportion and incidence rate were examined to see if associated with age, sex, country, or severity.

CONCLUSIONS

We conclude that most TBIs are mild and most TBIs occur in males among the adult population. The incidence of TBI varies widely by ages and between countries. Despite being an important medical, economic, and social problem, the global epidemiology of TBI is still not well-characterized in the current literature. Understanding the incidence of TBI, particularly mild TBI, remains challenging because of nonstandardized reporting among neuroepidemiological studies.

Physical comorbidities increase the risk of psychiatric comorbidity in multiple sclerosis

BACKGROUND

Risk factors for psychiatric comorbidity in multiple sclerosis (MS) are poorly understood.

OBJECTIVE

We evaluated the association between physical comorbidity and incident depression, anxiety disorder, and bipolar disorder in a MS population relative to a matched general population cohort.

METHODS

Using population-based administrative data from Alberta, Canada we identified 9624 persons with MS, and 41,194 matches. Using validated case definitions, we estimated the incidence of depression, anxiety disorder, and bipolar disorder, and their association with physical comorbidities using Cox regression, adjusting for age, sex, socioeconomic status, and index year.

RESULTS

In both populations, men had a lower risk of depression and anxiety disorders than women, as did individuals who were ≥45 years versus <45 years at the index date. The risk of bipolar disorder declined with increasing age. The risks of incident depression (HR 1.92; 1.82-2.04), anxiety disorders (HR 1.52; 1.42-1.63), and bipolar disorder (HR 2.67; 2.29-3.11) were higher in the MS population than the matched population. These associations persisted essentially unchanged after adjustment for covariates including physical comorbidities. Multiple physical comorbidities were associated with psychiatric disorders in both populations.

CONCLUSION

Persons with MS are at increased risk of psychiatric comorbidity generally, and some physical comorbidities are associated with additional risk.

The prevalence of diagnosed tourette syndrome in Canada: A national population-based study

OBJECTIVE

The objective of this study was to examine: (1) the prevalence of diagnosed Tourette syndrome in Canada by sex in youth (aged 12-17) and adults and (2) socioeconomic factors in this population.

BACKGROUND

The majority of epidemiological studies of tics have focused on children and youth, with few studies describing the prevalence of tics in adult populations.

METHODS

Canadian data on Tourette syndrome prevalence were derived from the Canadian Community Health Survey 2010 and 2011 cycles, a Statistics Canada population-based cross-sectional survey that collects information related to health status. We determined the prevalence of diagnosed Tourette syndrome and examined sociodemographic factors, including age, sex, education, income, employment, and birthplace.

RESULTS

Overall, 122,884 Canadians participated in the surveys, with 122 participants diagnosed with Tourette syndrome. The prevalence of Tourette syndrome was higher in males in youth: 6.03 per 1000 (95% confidence interval: 3.24-8.81) in males versus 0.48 per 1,000 (95% confidence interval: 0.05-0.91) in females, with a prevalence risk ratio of 5.31 (95% confidence interval: 2.38-11.81). In adults, the prevalence of Tourette syndrome was 0.89 per 1,000 (95% confidence interval: 0.48-1.29) in males versus 0.44 (95% confidence interval: 0.16.0-0.71) in females, with a prevalence risk ratio of 1.93 (95% confidence interval: 1.21-3.08). After adjusting for age and sex, adults with Tourette syndrome had lower odds of receiving postsecondary education or being employed and higher odds of having income lower than the median and receiving governmental support.

CONCLUSION

Data on the prevalence of Tourette syndrome in adults are scarce because most studies focus on children. Our data demonstrate a decreasing prevalence risk ratio for sex in adults compared to children. A diagnosis of Tourette syndrome is associated with lower education, income, and employment in adulthood. © 2016 International Parkinson and Movement Disorder Society.

Systematic review of validated case definitions for diabetes in ICD-9-coded and ICD-10-coded data in adult populations

OBJECTIVES

With steady increases in 'big data' and data analytics over the past two decades, administrative health databases have become more accessible and are now used regularly for diabetes surveillance. The objective of this study is to systematically review validated International Classification of Diseases (ICD)-based case definitions for diabetes in the adult population.

SETTING, PARTICIPANTS AND OUTCOME MEASURES

Electronic databases, MEDLINE and Embase, were searched for validation studies where an administrative case definition (using ICD codes) for diabetes in adults was validated against a reference and statistical measures of the performance reported.

RESULTS

The search yielded 2895 abstracts, and of the 193 potentially relevant studies, 16 met criteria. Diabetes definition for adults varied by data source, including physician claims (sensitivity ranged from 26.9% to 97%, specificity ranged from 94.3% to 99.4%, positive predictive value (PPV) ranged from 71.4% to 96.2%, negative predictive value (NPV) ranged from 95% to 99.6% and κ ranged from 0.8 to 0.9), hospital discharge data (sensitivity ranged from 59.1% to 92.6%, specificity ranged from 95.5% to 99%, PPV ranged from 62.5% to 96%, NPV ranged from 90.8% to 99% and κ ranged from 0.6 to 0.9) and a combination of both (sensitivity ranged from 57% to 95.6%, specificity ranged from 88% to 98.5%, PPV ranged from 54% to 80%, NPV ranged from 98% to 99.6% and κ ranged from 0.7 to 0.8).

CONCLUSIONS

Overall, administrative health databases are useful for undertaking diabetes surveillance, but an awareness of the variation in performance being affected by case definition is essential. The performance characteristics of these case definitions depend on the variations in the definition of primary diagnosis in ICD-coded discharge data and/or the methodology adopted by the healthcare facility to extract information from patient records.

The Standards of Reporting of Neurological Disorders (STROND) checklist: Application to multiple sclerosis

Background:

Descriptive epidemiological studies documenting the incidence and prevalence of multiple sclerosis (MS) and studies that report morbidity, mortality, and economic burden provide essential information for patients, healthcare providers, and policymakers. However, the quality of reporting of observational studies is often poor, limiting the ability to evaluate the validity of the findings. The Standards of Reporting of Neurological Disorders (STROND) reporting guideline comprises recommendations and a 15-item checklist of reporting items to aid high-quality reporting of incidence and prevalence studies of neurological disorders.

Methods:

We explain the basic reporting items of the STROND checklist for the methods, results, and discussion sections in the context of the MS literature and searched for examples of good reporting of those items.

Results:

We identified examples of good reporting of the basic reporting items from previous systematic reviews of the descriptive epidemiologic literature in MS.

Conclusion:

The adoption of the STROND reporting guidelines should improve the quality of reporting of descriptive epidemiological studies in MS. Along with efforts to improve methodological aspects of epidemiological studies and harmonization of data collection efforts, improved reporting could contribute to furthering our understanding of the epidemiology of MS.

Detecting depression in Parkinson disease: A systematic review and meta-analysis

BACKGROUND

Failure to detect depression in patients with Parkinson disease (PD) can lead to worsened outcomes for patients and caregivers. Accurate identification of depression would enable practitioners to provide comprehensive care for their patients with PD.

METHODS

Our objective was to examine the diagnostic accuracy of tools for detecting depression in adult outpatients with PD. We searched MEDLINE, PsycINFO, and EMBASE (inception to December 1, 2015), gray literature, and bibliographies of included studies. The pooled prevalence of depression across studies and diagnostic accuracy estimates were calculated using random-effects models. Diagnostic accuracy estimates were calculated across the best-reported cutoffs from each study and across specific cutoffs, when feasible.

RESULTS

Out of 8,184 citations, 21 studies were included, evaluating 24 tools, with 4 amenable to meta-analysis. The pooled prevalence of major depression was 22.9% (95% confidence interval [CI] 18.1-27.7). The 15-item Geriatric Depression Scale (GDS-15) had a pooled sensitivity of 0.81 (95% CI 0.64-0.91) and specificity of 0.91 (95% CI 0.87-0.94). The most sensitive cutoff for the GDS-15 was 5 at 0.91 (95% CI 0.83-1.00). The Beck Depression Inventory I/Ia had a pooled sensitivity of 0.79 (95% CI 0.61-0.90) and specificity of 0.85 (95% CI 0.79-0.90). The Montgomery-Åsberg Depression Rating Scale yielded a pooled sensitivity of 0.77 (95% CI 0.69-0.83) and specificity of 0.92 (95% CI 0.79-0.97). The Unified Parkinson's Disease Rating Scale had a pooled sensitivity of 0.72 (95% CI 0.64-0.79) and specificity of 0.80 (95% CI 0.70-0.87). All estimates had heterogeneity.

CONCLUSIONS

There are several valid tools for detecting depression in patients with PD. Practitioners should choose one that fits their clinical practice.

Chronic lung disease and multiple sclerosis: Incidence, prevalence, and temporal trends

OBJECTIVES

We aimed to estimate the incidence and prevalence of chronic lung disease (CLD), including asthma and chronic obstructive pulmonary disease, in the MS population versus a matched cohort from the general population.

METHODS

We used population-based administrative data from four Canadian provinces to identify 44,452 persons with MS and 220,849 age-, sex- and geographically-matched controls aged 20 years and older. We employed a validated case definition to estimate the incidence and prevalence of CLD over the period 1995-2005, and used Poisson regression to assess temporal trends.

RESULTS

In 2005, the crude incidence of CLD per 100,000 persons was 806 (95%CI: 701-911) in the MS population, and 757 in the matched population (95%CI: 712-803). In 2005, the crude prevalence of CLD was 13.5% (95%CI: 13.1-14.0%) in the MS population, and 12.4% (95%CI: 12.3-12.6%) in the matched population. Among persons aged 20-44 years, the average annual incidence of CLD was higher in the MS population than in the matched population (RR 1.15; 95%CI: 1.02-1.30), but did not differ between populations for those aged ≥45 years. The incidence of CLD was stable, but the prevalence of CLD increased 60% over the study period.

CONCLUSION

CLD is relatively common in the MS population. The incidence of CLD has been stable over time, but the prevalence of CLD has increased. Among persons aged 20-44 years, CLD is more common in the MS population than in a matched population. Given the prevalence of CLD in the MS population, further attention to the effects of CLD on outcomes in MS and approaches to mitigating those effects are warranted.

The Incidence of Parkinson's Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Parkinson's disease (PD) is a common neurodegenerative disorder. Epidemiological studies on the incidence of PD are important to better understand the risk factors for PD and determine the condition's natural history.

OBJECTIVE

This systematic review and meta-analysis examine the incidence of PD and its variation by age and gender.

METHODS

We searched MEDLINE and EMBASE for epidemiologic studies of PD from 2001 to 2014, as a previously published systematic review included studies published until 2001. Data were analyzed separately for age group and gender, and meta-regression was used to determine whether a significant difference was present between groups.

RESULTS

Twenty-seven studies were included in the analysis. Meta-analysis of international studies showed rising incidence with age in both men and women. Significant heterogeneity was observed in the 80+ group, which may be explained by methodological differences between studies. While males had a higher incidence of PD in all age groups, this difference was only statistically significant for those in the age range 60-69 and 70-79 (p < 0.05).

CONCLUSION

PD incidence generally increases with age, although it may stabilize in those who are 80+.

The Association of Smoking and Surgery in Inflammatory Bowel Disease is Modified by Age at Diagnosis

Objectives:

We assessed the association of smoking at diagnosis of inflammatory bowel disease (IBD) on the need for an intestinal resection.

Methods:

The Health Improvement Network was used to identify an inception cohort of Crohn's disease (n=1519) and ulcerative colitis (n=3600) patients from 1999–2009. Poisson regression explored temporal trends for the proportion of newly diagnosed IBD patients who never smoked before their diagnosis and the risk of surgery within 3 years of diagnosis. Cox proportional hazard models assessed the association between smoking and surgery, and effect modification was explored for age at diagnosis.

Results:

The rate of never smokers increased by 3% per year for newly diagnosed Crohn's disease patients (incidence rate ratio (IRR) 1.03; 95% confidence interval (CI): 1.02–1.05), but not for ulcerative colitis. The rate of surgery decreased among Crohn's disease patients aged 17–40 years (IRR 0.96; 95% CI: 0.93–0.98), but not for ulcerative colitis. Smoking at diagnosis increased the risk of surgery for Crohn's disease patients diagnosed after the age of 40 (hazard ratio (HR) 2.99; 95% CI: 1.52–5.92), but not for those diagnosed before age 40. Ulcerative colitis patients diagnosed between the ages of 17 and 40 years and who quit smoking before their diagnosis were more likely to undergo a colectomy (ex-smoker vs. never smoker: HR 1.66; 95% CI: 1.04–2.66). The age-specific findings were consistent across sensitivity analyses for Crohn's disease, but not ulcerative colitis.

Conclusions:

In this study, the association of smoking and surgical resection was dependent on the age at diagnosis of IBD.

A systematic review of clinical decision rules for epilepsy

Clinical decision rules (CDRs) have been empirically demonstrated to improve patient satisfaction and enhance cost-effective care. The use of CDRs has not yet been robustly explored for epilepsy. We performed a systematic review of MEDLINE (from 1946) and Embase (from 1947) using Medical Subject Headings and keywords related to CDRs and epilepsy. We included original research of any language deriving, validating, or implementing a CDR using standardized definitions. Study quality was determined using a modified version of previously published criteria. A bivariate model was used to meta-analyze studies undergoing sequential derivation and validation studies. Of 2445 unique articles, 5 were determined to be relevant to this review. Three were derivation studies (three diagnostic and one therapeutic), one validation study, and one combined derivation and validation study. No implementation studies were identified. Study quality varied but was primarily of a moderate level. Two CDRs were validated and, thus, able to be meta-analyzed. Although initial measures of accuracy were high (sensitivity ~80% or above), they tended to diminish significantly in the validation studies. The pooled estimates of sensitivity and specificity both exhibited wide 95% confidence and prediction intervals that may limit their utility in routine practice. Despite the advances in therapeutic and diagnostic interventions for epilepsy, few CDRs have been developed to guide their use. Future CDRs should address common clinical scenarios such as efficient use of diagnostic tools and optimal clinical treatment decisions. Given their potential for advancing efficient, evidence-based, patient-centered healthcare, CDR development should be a priority in epilepsy.

Sex differences in comorbidity at diagnosis of multiple sclerosis: A population-based study

Objective:

To determine the prevalence of comorbidity in the multiple sclerosis (MS) population at the time of MS diagnosis. We also compared the prevalence of comorbidity in the MS population to that in a matched cohort from the general population.

Methods:

Using population-based administrative health data from 4 Canadian provinces, we identified 23,382 incident MS cases and 116,638 age-, sex-, and geographically matched controls. We estimated the prevalence of hypertension, diabetes, hyperlipidemia, heart disease, chronic lung disease, epilepsy, fibromyalgia, inflammatory bowel disease, depression, anxiety, bipolar disorder, and schizophrenia at MS diagnosis using validated case definitions. We compared the populations using rate ratios.

Results:

Of the MS cases, 16,803 (71.9%) were female. The most prevalent comorbidity was depression (19.1%). Compared to the matched population, all comorbidities except hyperlipidemia were more common in the MS population. Relative to the matched populations, the prevalence of hypertension was 16% higher for women with MS and 48% higher for men with MS, thus there was a disproportionately higher prevalence of hypertension in men with MS than women. Men with MS also had a disproportionately higher prevalence than women with MS for diabetes, epilepsy, depression, and anxiety.

Conclusions:

Comorbidity is more common than expected in MS, even around the time of diagnosis. The prevalence of psychiatric comorbidity is particularly high and highlights the need for clinical attention to this issue. The observed sex-specific differences in the burden of comorbidity in MS, which differ from those in the matched population, warrant further investigation.