How common is comorbidity and why does it occur?

Comorbidity is most generally defined as the co-occurrence of two or more mental health problems. Comorbidity between drug and other psychological disorders has emerged as a major clinical, public health and research issue over the past few decades. The reasons for comorbidity are complex. Furthermore, comorbidity is often associated with poor treatment outcome, severe illness course, and high service utilisation. This presents a significant challenge with respect to the identification, prevention and management of people with comorbid disorders. The unmet need for treatment within this group is considerable and the lack of research is unacceptable. This paper will give a brief overview of epidemiological research into comorbidity; and examine the reasons why comorbidity might occur.

Comorbidity: Cannabis and complexity

Cannabis is one of the most commonly used illicit drugs, and its effects have traditionally been seen as less harmful than outcomes associated with the highly prevalent use of alcohol and other illicit substances (e.g., cocaine and amphetamines), and injecting drugs. Consequently, less attention has been focused on developing and evaluating interventions in this area. However, current research supports the idea that cannabis does pose a number of acute and chronic health risks to the individual and to society. The authors review findings concerning the physiological and neurological effects of cannabis, prevalence of use, and studies concerning its possible role as a "gateway" drug. Diagnostic criteria for cannabis dependence and abuse are discussed, with a focus on whether a cannabis withdrawal syndrome exists and if so how it can be diagnosed. There is strong support for a link between cannabis and the development and exacerbation of psychosis and other mental health conditions (e.g., anxiety, depression). Further research is needed to determine the underlying neurochemical processes and their possible contribution to etiology, as well as the social factors that contribute to the increasing use of cannabis by young people. In addition there is a need for systematic evaluation using randomized controlled trials to determine effective prevention and treatment strategies. A number of public health programs that address cannabis use are reviewed along with available evidence for their effectiveness.

Comorbidity and genotype modify receptor expression in human alcoholics

Chronic alcohol misuse leads to both widespread and localized damage in human cerebral cortex. The latter, as neuronal loss, is marked in superior frontal cortex (SFC) but milder in primary motor cortex (PMC) and elsewhere. Quantitative morphometry by Harper et al showed that neuronal loss is greater in alcoholics with comorbidity (Wernicke Korsakoff syndrome, liver cirrhosis). Previous work revealed a paradox: the marked differences in GABAA receptor density, pharmacology, and expression between alcoholics without cormorbidity and controls are muted or absent in cirrhotic alcoholics. This concurs with work by the Butterworth group on hepatic encephalopathy cases — most of whom had an alcoholic ætiology — who show only minor differences from controls. Glutamate receptor differences are muted in many autopsy studies, though we have evidence that NMDA site pharmacology may vary in cirrhotic alcoholics. Here we used Real-Time PCR normalized to GAPDH deltaCT to quantify NMDA NR1, NR2A and NR2B subunit expression in SFC and PMC samples obtained at autopsy from alcoholics with and without comorbid cirrhosis and matched controls. Overall subunit transcript expression was signifi cantly lower in alcoholic cirrhotics than in either of the other groups (F2,42 = 12.942, P < 0.001). The effect was most marked for the NR1 subunit; males differed from females, particularly in SFC. The data suggest that if excitotoxicity mediates neuronal loss in SFC, it may be implemented differently: passively in uncomplicated alcoholics, by altered GABAergic transmission; actively in cirrhotic alcoholics, by altered glutamatergic transmission. We also subdivided cases on a panel of genetic markers. Different genotypes interacted with NMDA and GABAA pharmacology and expression. Cirrhotic and uncomplicated alcoholics may differ pathogenically because of inherent characteristics in addition to possible neurotoxic sequelæ to the liver damage.

Patterns of diagnostic comorbidity in children and adolescents with anxiety

Comorbidity is defined as the co-occurrence of two or more psychological disorders and has been identified as one of the most pressing issues facing child psychologists today. Unfortunately, research on comorbidity in anxious children is rare. The purpose of this research was to examine how specific comorbid patterns in children and adolescents referred with anxiety disorders affected clinical presentation. In addition, the effects of gender, age and total number of diagnoses were also examined.^ Three hundred fifty-five children and adolescents (145 girls and 210 boys, hereafter referred to as "children") aged 6 to 17 who presented to the Child Anxiety and Phobia Program during the years 1987 through 1996 were assessed through a structured clinical interview administered to both the children and their families. Based on information from both children and parents, children were assigned up to five DSM diagnoses. Global ratings of severity were also obtained. While children were interviewed, parents completed a number of questionnaires pertaining to their child's overall functioning, anxiety, thoughts and behaviors. Similarly, while parents were interviewed, children completed a number of self-report questionnaires concerning their own thoughts, feelings and behaviors.^ In general, children with only anxiety disorders were rated as severe as children who met criteria for both anxiety and externalizing disorders. Children with both anxiety and externalizing disorders were mostly young (i.e. age 6 through 11) and mostly male. These children tended to rate themselves (and be rated by their parents) equally as anxious as children with only anxiety disorders. Global ratings of severity tended to be associated with the type of comorbid pattern versus the number of diagnoses assigned to a child. The theoretical, development and clinical implications of these findings will be discussed. ^

Substance use disorder comorbidity with schizophrenia in families of Mexican and Central American Ancestry

artículo -- Universidad de Costa Rica. Centro Investigación en Biología Molecular y Celular, 2010. Este documento es privado debido a limitaciones de derechos de autor.

Psychosocial Risk Factors, Interventions, and Comorbidity in Patients with Non-Specific Low Back Pain in Primary Care: Need for Comprehensive and Patient-Centered Care

International audience

Psychosocial, musculoskeletal and somatoform comorbidity in patients with chronic low back pain: original results from the Dutch Transition Project

International audience

The prevalence, age distribution and comorbidity of personality disorders in Australian women

OBJECTIVE: We aimed to describe the prevalence and age distribution of personality disorders and their comorbidity with other psychiatric disorders in an age-stratified sample of Australian women aged ⩾25 years. METHODS: Individual personality disorders (paranoid, schizoid, schizotypal, histrionic, narcissistic, borderline, antisocial, avoidant, dependent, obsessive-compulsive), lifetime mood, anxiety, eating and substance misuse disorders were diagnosed utilising validated semi-structured clinical interviews (Structured Clinical Interview for DSM-IV-TR Axis I Disorders, Research Version, Non-patient Edition and Structured Clinical Interview for DSM-IV Axis II Personality Disorders). The prevalence of personality disorders and Clusters were determined from the study population (n = 768), and standardised to the Australian population using the 2011 Australian Bureau of Statistics census data. Prevalence by age and the association with mood, anxiety, eating and substance misuse disorders was also examined. RESULTS: The overall prevalence of personality disorders in women was 21.8% (95% confidence interval [CI]: 18.7, 24.9). Cluster C personality disorders (17.5%, 95% CI: 16.0, 18.9) were more common than Cluster A (5.3%, 95% CI: 3.5, 7.0) and Cluster B personality disorders (3.2%, 95% CI: 1.8, 4.6). Of the individual personality disorders, obsessive-compulsive (10.3%, 95% CI: 8.0, 12.6), avoidant (9.3%, 95% CI: 7.1, 11.5), paranoid (3.9%, 95% CI: 3.1, 4.7) and borderline (2.7%, 95% CI: 1.4, 4.0) were among the most prevalent. The prevalence of other personality disorders was low (⩽1.7%). Being younger (25-34 years) was predictive of having any personality disorder (odds ratio: 2.36, 95% CI: 1.18, 4.74), as was being middle-aged (odds ratio: 2.41, 95% CI: 1.23, 4.72). Among the strongest predictors of having any personality disorder was having a lifetime history of psychiatric disorders (odds ratio: 4.29, 95% CI: 2.90, 6.33). Mood and anxiety disorders were the most common comorbid lifetime psychiatric disorders. CONCLUSIONS: Approximately one in five women was identified with a personality disorder, emphasising that personality disorders are relatively common in the population. A more thorough understanding of the distribution of personality disorders and psychiatric comorbidity in the general population is crucial to assist allocation of health care resources to individuals living with these disorders.

The relationship between divorce and children with AD/HD of different subtypes and comorbidity: results from a clinically referred sample

This study investigated the relationship between divorce and thesymptom profile of children with attention deficit/hyperactivity disorder(AD/HD). The files of 1,201 children from a pediatric practicein Sydney, Australia were used in this study. Children wereaged 6 to 18 years, and were diagnosed with either the inattentiveor combined type of AD/HD. Results show that 213 children hadparents who were divorced. Children with the combined type, andespecially boys with comorbid conduct disorder/oppositional defiantdisorder (CD/ODD) were more common in the divorced group,and children of the inattentive type with comorbid learning disabilitieswere overrepresented in nondivorced families. Results suggestthat divorce is associated with disruptive behavior patterns inchildren with AD/HD. The importance of including marital status asan important correlate in AD/HD treatment outcomes is discussed.

Controversies revisited: a systematic review of the comorbidity of depression and anxiety with inflammatory bowel diseases

BACKGROUND: Although mental health concerns are known to occur commonly for those with inflammatory bowel diseases (IBD), the nature of this comorbid relationship has not been systematically reviewed to date. A review in 2007 identified 5 controversies regarding anxiety/depression rates and various comparators between and within IBD. We aimed to systematically analyze and critique the current evidence regarding this comorbidity, providing an update to the 5 controversies.

METHODS: Ebscohost Medline, CINAHL, Embase, and PsychINFO were searched between 2005 and 2014 using systematic review methodology. Controlled quantitative studies examining either symptoms or diagnoses of anxiety and depression in IBD were included in the review, with study quality assessed using a scale developed a priori to evaluate observational research.

RESULTS: (1) IBD versus healthy controls (pooled mean proportions) (n = 13 studies): anxiety 19.1% versus 9.6%, depression 21.2% versus 13.4%; (2) IBD inactive versus IBD active disease (n = 26): anxiety 28.2% versus 66.4%, depression 19.9% versus 34.7%; (3) ulcerative colitis versus Crohn's disease (n = 28): anxiety 31% versus 37%, depression 22% versus 24.4%; (4) IBD versus other chronic medical conditions (n = 17): anxiety 41.9% versus 48.2%, depression 14.5% versus 28.4%; (5) onset of anxiety/depression before or after IBD onset (n = 2): adults more likely to develop anxiety/depression before IBD onset, but a substantial proportion develops depression after onset; an increased risk for children of developing anxiety/depression after IBD onset.

CONCLUSIONS: The high rates of anxiety and depression for those with IBD, particularly when disease is active, warrant a systemic approach to screening and treatment.

Neurocognitive profiles of people with comorbid depression and alcohol use : implications for psychological interventions

Depression and alcohol use disorders frequently co-occur and are highly prevalent. Both conditions are known to impair cognitive functioning, yet research into the role of these impairments in response to Cognitive Behaviour Therapy (CBT) is limited. The purpose of the present study was to examine the relationship between baseline neuropsychological performance, severity of depressive symptoms and alcohol use disorders. Participants with current depression and hazardous alcohol use were functioning in the average range on all neuropsychological measures prior to treatment entry. Baseline measures of drinking severity and a range of cognitive functions were inversely correlated. After controlling for other baseline variables, superior baseline cognitive functioning predicted greater reductions in depression severity after 17 weeks. These predictive effects occurred across both brief and extended interventions. Findings suggest that improvement in depression following psychological treatment is enhanced by greater fluid reasoning ability and is predicted by executive functioning, regardless of the treatment length or problem focus.