Rising incidence of psychiatric disorders before diagnosis of immune-mediated inflammatory disease

Abstract

Aims. After the diagnosis of immune-mediated inflammatory diseases (IMID) such as inflammatory bowel disease (IBD), multiple sclerosis (MS) and rheumatoid arthritis (RA), the incidence of psychiatric comorbidity is increased relative to the general population. We aimed to determine whether the incidence of psychiatric disorders is increased in the 5 years before the diagnosis of IMID as compared with the general population.Methods. Using population-based administrative health data from the Canadian province of Manitoba, we identified all persons with incident IBD, MS and RA between 1989 and 2012, and cohorts from the general population matched 5 : 1 on year of birth, sex and region to each disease cohort. We identified members of these groups with at least 5 years of residency before and after the IMID diagnosis date. We applied validated algorithms for depression, anxiety disorders, bipolar disorder, schizophrenia, and any psychiatric disorder to determine the annual incidence of these conditions in the 5-year periods before and after the diagnosis year.Results. We identified 12 141 incident cases of IMID (3766 IBD, 2190 MS, 6350 RA) and 65 424 matched individuals. As early as 5 years before diagnosis, the incidence of depression [incidence rate ratio (IRR) 1.54; 95% CI 1.30-1.84) and anxiety disorders (IRR 1.30; 95% CI 1.12-1.51) were elevated in the IMID cohort as compared with the matched cohort. Similar results were obtained for each of the IBD, MS and RA cohorts. The incidence of bipolar disorder was elevated beginning 3 years before IMID diagnosis (IRR 1.63; 95% CI 1.10-2.40).Conclusion. The incidence of psychiatric comorbidity is elevated in the IMID population as compared with a matched population as early as 5 years before diagnosis. Future studies should elucidate whether this reflects shared risk factors for psychiatric disorders and IMID, a shared final common inflammatory pathway or other aetiology.

Genetic correlations among psychiatric and immune-related phenotypes based on genome-wide association data

“…These findings are consistent with available epidemiological evidence indicating that the presence of one set of disorders portends increased risk for a diagnosis from the other class of disorders, though the causality and temporality of these relationships is not clearly established. [76][77][78][79][80][81][82] Positive genetic inter-correlations among these phenotypes are also consistent with recent work demonstrating that the positive correlation between BD and SZ are significantly mediated by both CNS and immunologic tissues. 83 Our local genetic correlation analyses were inadequately powered to detect loci relevant to most of the psychiatric-immune disorder pairs, including BD.…”

Interactions between psychiatric and physical disorders and their effects on the risks of suicide: a nested case–control study

“…Previous studies have indicated that, in addition to genetic and environmental factors, the onset and progression of schizophrenia are also linked to deficits in dopamine secretion in the endocrine and central nervous systems, as well as other immune mechanisms. 54,63 An extended psychiatric history has many drawbacks, such as loss of function, economic burden, family or work issues, diagnostic difficulties, relapse risk, or a general unwillingness to follow medical advice, again leading to elevated suicide risk. 64 In the present study, we observed a high risk of suicide in patients who developed psychiatric disorders after physical illness, which may reflect the failure to detect worsening of psychiatric symptoms following the onset of physical symptoms.…”

“…− Such studies have indicated that patients with psychiatric disorders may experience worsening of cardiovascular diseases due to dysfunction of the HPA axis and autonomic nervous system, thereby leading to increased levels of cortisol, blood cholesterol (triglycerides), and blood pressure . Some studies have also indicated that psychiatric disorders are associated with platelet activation and dysregulation of the immunoinflammatory system, increasing the risk of cardio‐ and cerebrovascular diseases.…”

“…We encountered a high prevalence of patients with schizophrenia in our study. Previous studies have indicated that, in addition to genetic and environmental factors, the onset and progression of schizophrenia are also linked to deficits in dopamine secretion in the endocrine and central nervous systems, as well as other immune mechanisms . An extended psychiatric history has many drawbacks, such as loss of function, economic burden, family or work issues, diagnostic difficulties, relapse risk, or a general unwillingness to follow medical advice, again leading to elevated suicide risk …”

Pre-print supplementary material

“…Twelve citations reported the incidence of psychotic disorders in a population group with a preexiting comorbidity and compared it with a general population cohort [27][28][29][30][31][32][33][34][35][36][37][38] . These studies are summarized in Table 6 below.…”