Affective disorders in neurological diseases: a case register-based study

Lithium versus anticonvulsants and the risk of physical disorders - Results from a comprehensive long-term nation-wide population-based study emulating a target trial

Bipolar disorder is associated with increased rates of many physical disorders, but the effects of medication are unclear. We systematically investigated the associations between sustained use of first line maintenance agents, lithium versus lamotrigine and valproate, and the risk of physical disorders using a nation-wide population-based target trial emulation covering the entire 5.9 million inhabitants in Denmark. We identified two cohorts. Cohort 1: patients with a diagnosis of bipolar disorder prior to first purchase (N = 12.607). Cohort 2: all 156.678 adult patients who had their first ever purchase (since 1995) of either lithium, lamotrigine or valproate between 1997 and 2021 regardless of diagnosis. Main analyses investigated the effect of sustained exposure defined as exposure for all consecutive 6-months periods during a 10-year follow-up. Outcomes included a diagnosis of incident stroke, arteriosclerosis, angina pectoris, myocardial infarction, diabetes mellitus, myxedema, osteoporosis, dementia, Parkinson's disease, chronic kidney disease and cancer (including subtypes). In both Cohorts 1 and 2, there were no systematic statistically significant differences in associations between sustained use of lithium versus lamotrigine and valproate, respectively, and any physical disorder, including subtypes of disorders, except myxedema, for which exposure to lithium increased the absolute risk of myxedema with 7-10 % compared with lamotrigine or valproate. In conclusion, these analyses emulating a target trial of "real world" observational register-based data show that lithium does not increase the risk of developing any kind of physical disorders, except myxedema, which may be a result of detection bias.

Why is lithium [not] the drug of choice for bipolar disorder? a controversy between science and clinical practice

BACKGROUND

During over half a century, science has shown that lithium is the most efficacious treatment for bipolar disorder but despite this, its prescription has consistently declined internationally during recent decades to approximately 35% ever use or less of patients with bipolar disorder.

CONTENT

This narrative review provides an overview of the decreasing use of lithium in bipolar disorder internationally, shortly summarises the evidence for lithium's acute and prophylactic effects in bipolar disorder, discuss the challenges in relation to lithium including side effects, long-term risks and myths around lithium and provides two detailed examples on how specialised care models may result in successful increase of the use of lithium to 70% of patients with bipolar disorder largescale and improve care regionally and nationally.

CONCLUSIONS

Decades of scientific investigations and education and teaching of clinicians and the public has not increased the use of lithium on a population-based large scale. It is argued that lithium should be the drug of choice for maintenance therapy as the single first-line treatment and that organizational changes are needed with specialised care for bipolar disorder to systematically and long-term change the use of lithium on a large-scale population-level.

Increased rate of treatment with antidepressants in patients with multiple sclerosis

The prevalence of depression and anxiety is increased in patients with multiple sclerosis, but it has not been investigated whether these conditions are treated in clinical practice. The objective of this study was to investigate whether the rate of treatment with antidepressants is increased in patients with multiple sclerosis compared with patients with other chronic illnesses and compared with the general population. By linkage of nationwide case registers, all patients were identified, who had received a main diagnosis of multiple sclerosis or osteoarthritis at first admission or during outpatient contact in the period 1995-2000 in Denmark. Rates of subsequent purchase of antidepressants for these patients were calculated. In total, 417 patients with a main diagnosis of multiple sclerosis and 12 127 patients with a main diagnosis of osteoarthritis, at first discharge from hospital or outpatient contact, were included. Patients with a diagnosis of multiple sclerosis had a 3.21 [95% confidence intervals (CI): 2.56-4.03] times increased rate of subsequently purchasing antidepressants compared with patients with a first diagnosis of osteoarthritis, and a 4.75 times (95% CI: 3.91-5.76) increased rate when compared with the rate among a gender-matched, age-matched, and calendar-matched sample of the general population. The rates were increased in all subgroups of patients regardless of gender, age, socioeconomic group, and time elapsed since diagnosis.

Increased rate of treatment with antidepressants in patients with epilepsy

The risk of depressive and anxiety disorders is increased among patients with epilepsy, but it is not known whether patients are treated with antidepressants in clinical practice. In a nationwide case register linkage study, all patients who received a main diagnosis of epilepsy or osteoarthritis on first admission or outpatient contact during the period 1995 to 2000 in Denmark were identified, and rates of subsequent purchases of antidepressants were calculated. Comparisons were also made with a gender-, age-, and calendar-matched sample of the general population. Patients diagnosed with epilepsy had a 1.73 (95% CI: 1.45-2.06) times increased rate of subsequently purchasing antidepressants, compared with patients diagnosed with osteoarthritis and a 2.44 times (95% CI: 2.12-2.81) increased rate compared with the rate among the general population. It is concluded that patients with epilepsy have a moderately increased probability of being prescribed antidepressants in clinical practice.

Associations between major depression, bipolar disorders, dysthymia and cardiovascular diseases in the general adult population

BACKGROUND

Cardiovascular diseases (CVD) and affective disorders are both very prevalent in the general population. However, it is unclear on a population level if the prevalence of different subtypes of affective disorders like unipolar major depression or dysthymia is different in individuals with specific CVDs.

METHODS

In 4,181 participants of the general population, lifetime prevalences for affective disorders were assessed through the Composite International Diagnostic Interview and cardiovascular diseases by self-report and subsequent physician-verified diagnosis. Multivariable logistic regression was used in the analysis.

RESULTS

Prevalences of unipolar depression, bipolar disorder and dysthymia were significantly higher in participants with coronary heart disease or stroke compared to those without these CVDs. Dysthymia had a stronger (OR = 2.03; 95% CI = 1.21-3.39) association with coronary heart disease than unipolar depression (OR = 1.58; 95% CI = 1.09-2.30) or any depression (OR = 1.92; 95% CI = 1.37-2.70). In contrast, unipolar depression (OR = 2.27; 95% CI = 1.29-3.99) showed a significant OR for the relation with stroke compared to dysthymia that reached no statistical significance. The commonly used category 'any depression' revealed higher odds (OR = 2.50; 95% CI = 1.46-4.28) for the relationship with stroke than unipolar depression or dysthymia, but lower odds than bipolar I disorder (OR = 5.71, 95% CI = 1.23-26.66).

CONCLUSIONS

Classification into diagnostic subgroups of affective disorders is important for an improved clinical and pathophysiological understanding of their relationship with CVDs. Dysthymia, in particular, plays an important role regarding the relation of affective disorders and CVDs. Future research on biological models may elucidate the pathophysiological link between subtypes of affective disorders and CVDs.

Neuropsychiatric symptoms in patients with multiple sclerosis

OBJECTIVE

To explore the range of psychiatric symptoms in patients with multiple sclerosis (MS) and their association with neurological disability.

METHOD

Patients diagnosed with MS during 1998-2000 in Rogaland and Hordaland counties, western Norway, were included. Psychiatric symptoms were assessed by the Neuropsychiatric Inventory (NPI). Patients with systemic lupus erythematosus (SLE) served as controls.

RESULTS

Eighty-six of 93 eligible MS patients were included, and 80% showed at least one psychiatric symptom. The most frequent symptoms were depression (59%), sleep disturbance (48%), irritability/emotional lability (42%), and apathy (31%). Depression was associated with higher disability score. MS patients showed significantly higher NPI irritability score (P = 0.002), appetite disturbance score (P < 0.001), and apathy score (P = 0.01) than SLE patients.

CONCLUSION

Neuropsychiatric symptoms occur frequently in patients with MS. Irritability and apathy are independent of disability and chronic disease and represent unique disease manifestations.

Increased risk of developing affective disorder in patients with hypothyroidism: a register-based study

BACKGROUND

Links between thyroid function and depression have been noted in many contexts. We assessed whether hospitalization with hypothyroidism was a risk factor for developing affective disorder.

METHODS

We conducted a prospective cohort study using historical data from Danish registers. The observational period was 1977-1999. Three study cohorts were identified: all patients with a first hospital admittance with the resulting index discharge diagnoses hypothyroidism, osteoarthritis, or nontoxic goiter. A later hospitalization with a resulting discharge diagnosis of affective disorder was used as event of interest, and rates of readmission were estimated and compared using competing risk models in survival analyses.

FINDINGS

We identified 165,307 patients discharged with an index diagnosis. In the observational period, 1041 events occurred. An index diagnosis of hypothyroidism was associated with an increased risk of hospitalization with affective disorder when compared to the control diseases. The risk of hospitalization with affective disorder was greatest in the first year after index hospitalization.

CONCLUSION

Patients hospitalized with hypothyroidism have a greater risk of readmission with depression or bipolar disorder than control patients. This renders epidemiologic support to theories linking thyroid dysfunction with mood disturbances.

Development of neuropsychiatric symptoms in poststroke patients: a cross-sectional study

OBJECTIVE

The study aimed to characterize neuropsychiatric symptomatology and its evolution in a large group of poststroke patients during their first year.

METHOD

The Neuropsychiatric Inventory (NPI) was administered to a sample of 124 poststroke patients, divided into three independent groups on the basis of time from stroke (2, 6 and 12 months). The controls were 61 healthy subjects.

RESULTS

A wide range of neuropsychiatric symptoms was found significant in the poststroke population: mostly depression (61%), irritability (33%), eating disturbances (33%), agitation (28%), apathy (27%) and anxiety (23%). Modifications in terms of greater depression, anxiety, irritability and eating disturbances evolved in the year following stroke. Other symptoms were significantly present depending on time from stroke. Clear relations with other clinical and demographic variables were also found.

CONCLUSION

Neuropsychiatric symptoms constitute an important part of comorbidity in stroke patients; thus, suitable assessment tools may improve clinical understanding of these patients.