In this study, a classifier (hyperplane) is determined to distinguish the neural responses during emotion regulation versus viewing images in healthy adults and then applied to determine (i) the effectiveness of the emotion regulation response (defined as emotion regulation distance from the hyperplane [DFHER]) in independent samples of healthy adults, patients with BD, and the patients’ unaffected relatives (URs) and (ii) the association of DFHER with the duration of future (hypo)manic and depressive episodes for patients with BD over a 16-month follow-up period.

Study participants (N = 226) included 65 healthy adults (35 used for support vector machine [SVM] learning [HCTrain] and 30 kept as an independent test sample [HCTest]), 87 patients with newly diagnosed BD (67% BD type 2) and 74 URs. BOLD response data came from an emotion regulation task. Clinical symptoms were assessed at baseline fMRI and after 16 months of specialized treatment.

The SVM ML analysis identified a hyperplane with 75.7% accuracy. Patients with BD showed reduced DFHER relative to the HCTest and UR groups. Reduced DFHER was associated with reduced improvement in psychosocial functioning during the 16-month follow-up time (B = −1.663, p = 0.02).

The neural response during emotion regulation can be relatively well distinguished in healthy adults via ML. Patients with newly diagnosed BD show significant disruption in the recruitment of this emotion regulation response. Disrupted may indicate a reduced capacity for functional improvement during specialized treatment in a mood disorder clinic.

Impaired emotion regulation has been proposed as a putative endophenotype in bipolar disorder (BD). Functional magnetic resonance imaging (fMRI) studies investigating this in unaffected first-degree relatives (UR) have thus far yielded incongruent findings. Hence, the current paper examines neural subgroups among UR during emotion regulation.

71 UR of patients with BD and 66 healthy controls (HC) underwent fMRI scanning while performing an emotion regulation task. Hierarchical cluster analysis was performed on extracted signal change during emotion down-regulation in pre-defined regions of interest (ROIs). Identified subgroups were compared on neural activation, demographic, clinical, and cognitive variables.

Two subgroups of UR were identified: subgroup 1 (39 UR; 55%) was characterized by hypo-activity in the dorsolateral, dorsomedial, and ventrolateral prefrontal cortex and the bilateral amygdalae, but comparable activation to HC in the other ROIs; subgroup 2 (32 UR; 45%) was characterized by hyperactivity in all ROIs. Subgroup 1 had lower success in emotion regulation compared to HC and reported more childhood trauma compared to subgroup 2 and HC. Subgroup 2 reported more anxiety, lower functioning, and greater attentional vigilance toward fearful faces compared to HC. Relatives from both subgroups were poorer in recognizing positive faces compared to HC.

These findings may explain the discrepancy in earlier fMRI studies on emotion regulation in UR, showing two different subgroups of UR that both exhibited aberrant neural activity during emotion regulation, but in opposite directions. Furthermore, the results suggest that impaired recognition of positive facial expressions is a broad endophenotype of BD.

There is a compelling need for innovative intervention strategies for patients with affective disorders, given their increasing global prevalence and significant associated disability and impaired functioning. This study aimed to investigate whether a comprehensive multimodule individualized intervention (AWARE), targeting known mediators of functioning, improves functioning in affective disorders.

AWARE was a randomized, controlled, rater-blind clinical trial conducted at two centers in the Capital Region of Denmark (Clinicaltrials.gov, NCT 04701827). Participants were adults with bipolar disorder or major depressive disorder and impaired functioning. Participants were randomized to the six-month AWARE intervention or treatment as usual (TAU). The AWARE intervention is based on the International Classification of Functioning, Disability and Health (ICF) Brief Core Set for Bipolar and Unipolar Disorder.

The primary outcome was observation-based functioning using the Assessment of Motor and Process Skills (AMPS). Secondary outcomes were functioning, QoL, stress, and cognition.

Between February 2021 and January 2023, 103 patients were enrolled; 50 allocated to AWARE treatment and 53 to TAU (96 included in the full analysis set). There was no statistically significant differential change over time between groups in the primary outcome (AMPS), however, both groups showed a statistically significant improvement at endpoint. The AWARE intervention had a statistically significant effect compared with TAU on secondary outcomes of patient-reported functioning, stress and cognition.

Compared with TAU, the AWARE intervention was ineffective at improving overall functioning on the primary outcome, presumably due to the short duration of the intervention. Further development of effective treatments targeting functioning is needed.

There is a significant contribution of genetic factors to the etiology of bipolar disorder (BD). Unaffected first-degree relatives of patients (UR) with BD are at increased risk of developing mental disorders and may manifest cognitive impairments and alterations in brain functional and connective dynamics, akin to their affected relatives.

In this prospective longitudinal study, resting-state functional connectivity was used to explore stable and progressive markers of vulnerability i.e. abnormalities shared between UR and BD compared to healthy controls (HC) and resilience i.e. features unique to UR compared to HC and BD in full or partial remission (UR n = 72, mean age = 28.0 ± 7.2 years; HC n = 64, mean age = 30.0 ± 9.7 years; BD patients n = 91, mean age = 30.6 ± 7.7 years). Out of these, 34 UR, 48 BD, and 38 HC were investigated again following a mean time of 1.3 ± 0.4 years.

At baseline, the UR showed lower connectivity values within the default mode network (DMN), frontoparietal network, and the salience network (SN) compared to HC. This connectivity pattern in UR remained stable over the follow-up period and was not present in BD, suggesting a resilience trait. The UR further demonstrated less negative connectivity between the DMN and SN compared to HC, abnormality that remained stable over time and was also present in BD, suggesting a vulnerability marker.

Our findings indicate the coexistence of both vulnerability-related abnormalities in resting-state connectivity, as well as adaptive changes possibly promoting resilience to psychopathology in individual at familial risk.

Persistent cognitive deficits are prevalent in patients with bipolar disorder (BD) and unipolar disorder (UD), but treatments effectively targeting cognition in these mood disorders are lacking. This is partly due to poor insight into the neuronal underpinnings of cognitive deficits.

The aim of this functional magnetic resonance imaging (fMRI) study was to investigate the neuronal underpinnings of working memory (WM)-related deficits in somatically healthy, remitted patients with BD or UD (n = 66) with cognitive and functional impairments compared to 38 healthy controls (HC). The participants underwent neuropsychological testing and fMRI, while performing a visuospatial and a verbal N-back WM paradigm.

Relative to HC, patients exhibited hypo-activity across dorsolateral prefrontal cortex as well as frontal and parietal nodes of the cognitive control network (CCN) and hyper-activity in left orbitofrontal cortex within the default mode network (DMN) during both visuospatial and verbal WM performance. Verbal WM-related response in the left posterior superior frontal gyrus (SFG) within CCN was lower in patients and correlated positively with out-of-scanner executive function performance across all participants.

Our findings suggest that cognitive impairments across BD and UD are associated with insufficient recruitment of task-relevant regions in the CCN and down-regulation of task-irrelevant orbitofrontal activity within the DMN during task performance. Specifically, a lower recruitment of the left posterior SFG within CCN during verbal WM was associated with lower cognitive performance.

Childhood maltreatment is an established risk factor for incident unipolar disorder and bipolar disorder. It is separately observed that affective disorders (AD) are also associated with higher nucleoside damage by oxidation. Childhood maltreatment may induce higher levels of nucleoside damage by oxidation and thus contribute to the development of AD; however, this relation is only sparsely investigated.

In total, 860 participants (468 patients with AD, 151 unaffected first-degree relatives, and 241 healthy control persons) completed the Childhood Trauma Questionnaire (CTQ). The association between CTQ scores and markers of systemic DNA and RNA damage by oxidation as measured by urinary excretion of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) and 8-oxo-7,8-dihydroguanosine (8-oxoGuo) levels, respectively, was investigated.

In multiple regression models adjusted for sex- and age, 8-oxodG and 8-oxoGuo levels were found to be higher in individuals who had experienced more childhood maltreatment. These associations persisted in models additionally adjusted for body mass index, alcohol, and current smoking status. Emotional abuse, sexual abuse, and emotional neglect were principally responsible for the foregoing associations.

Our findings of an association between childhood maltreatment and oxidative stress markers suggest that childhood maltreatment overall, notably emotional abuse and emotional neglect, is associated with enhanced systemic damage to DNA and RNA in adulthood. Further, individuals with AD reported a higher prevalence of childhood maltreatment, which may induce higher levels of nucleoside damage by oxidation in adulthood, possibly leading to increased risk of developing AD. Longitudinal studies are needed to clarify this relationship further.

Patients with major depressive disorder (MDD) or bipolar disorder (BD) exhibit difficulties with emotional cognition even during remission. There is evidence for aberrant emotional cognition in unaffected relatives of patients with these mood disorders, but studies are conflicting. We aimed to investigate whether emotional cognition in unaffected first-degree relatives of patients with mood disorders is characterised by heterogeneity using a data-driven approach.

Data from 94 unaffected relatives (33 of MDD patients; 61 of BD patients) and 203 healthy controls were pooled from two cohort studies. Emotional cognition was assessed with the Social Scenarios Test, Facial Expression Recognition Test and Faces Dot-Probe Test. Hierarchical cluster analysis was conducted using emotional cognition data from the 94 unaffected relatives. The resulting emotional cognition clusters and controls were compared for emotional and non-emotional cognition, demographic characteristics and functioning.

Two distinct clusters of unaffected relatives were identified: a relatively ‘emotionally preserved’ cluster (55%; 40% relatives of MDD probands) and an ‘emotionally blunted’ cluster (45%; 29% relatives of MDD probands). ‘Emotionally blunted’ relatives presented with poorer neurocognitive performance (global cognition p = 0.010), heightened subsyndromal mania symptoms (p = 0.004), lower years of education (p = 0.004) and difficulties with interpersonal functioning (p = 0.005) than controls, whereas ‘emotionally preserved’ relatives were comparable to controls on these measures.

Our findings show discrete emotional cognition profiles that occur across healthy first-degree relatives of patients with MDD and BD. These emotional cognition clusters may provide insight into emotional cognitive markers of genetically distinct subgroups of individuals at familial risk of mood disorders.

Aberrant emotion regulation has been posited as a putative endophenotype of bipolar disorder (BD). We therefore aimed to compare the neural responses during voluntary down-regulation of negative emotions in a large functional magnetic resonance imaging study of BD, patients' unaffected first-degree relatives (URs), and healthy controls (HCs).

We compared neural activity and fronto-limbic functional connectivity during emotion regulation in response to aversive v. neutral pictures in patients recently diagnosed with BD (n = 78) in full/partial remission, their URs (n = 35), and HCs (n = 56).

Patients showed hypo-activity in the left dorsomedial, dorsolateral, and ventrolateral prefrontal cortex (DMPFC and DLPFC) during emotion regulation while viewing aversive pictures compared to HCs, with URs displaying intermediate neural activity in these regions. There were no significant differences between patients with BD and HCs in functional connectivity from the amygdala during emotion regulation. However, exploratory analysis indicated that URs displayed more negative amygdala–DMPFC coupling compared with HCs and more negative amygdala-cingulate DLPFC coupling compared to patients with BD. At a behavioral level, patients and their URs were less able to dampen negative emotions in response aversive pictures.

The findings point to deficient recruitment of prefrontal resources and more negative fronto-amygdala coupling as neural markers of impaired emotion regulation in recently diagnosed remitted patients with BD and their URs, respectively.

Few studies have reported real-life data on socio-economic functioning in patients with bipolar disorder and their unaffected first-degree relatives.

We used Danish nation-wide population-based longitudinal register linkage to investigate socio-economic functioning in 19 955 patients with bipolar disorder, their 13 923 siblings and 20 sex, age and calendar-matched control individuals from the general population. Follow-up was from 1995 to 2017.

Patients with a diagnosis of bipolar disorder had lower odds of having achieved the highest educational level [OR 0.75 (95% confidence interval (CI) 0.73–0.77)], being employed [OR 0.16 (95% CI 0.159–0.168)], having achieved the 80% highest quartile of income [OR 0.33 (95% CI 0.32–0.35)], cohabitating [OR 0.44 (95% CI 0.43–0.46)] and being married [OR 0.54 (95% CI 0.52–0.55)] at first contact to hospital psychiatry as inpatient or outpatient compared with control individuals from the general population. Similarly, siblings to patients with bipolar disorder had a lower functioning within all five socio-economic areas than control individuals. Furthermore, patients and partly siblings showed substantially decreased ability to enhance their socio-economic functioning during the 23 years follow-up compared to controls.

Socio-economic functioning is substantially decreased in patients with bipolar disorder and their siblings and does not improve during long-term follow-up after the initial hospital contact, highlighting a severe and overlooked treatment gap.

Brain-derived neurotrophic factor (BDNF), which facilitates neuroplasticity and synaptogenesis, may be decreased in bipolar disorder, but has not been systematically investigated in people with newly diagnosed bipolar disorder and unaffected first-degree relatives.

To compare BDNF levels in patients with newly diagnosed bipolar disorder, their unaffected first-degree relatives and healthy controls.

The study investigated plasma BDNF levels in patients (n = 371) with newly diagnosed bipolar disorder, their unaffected first-degree relatives (n = 98) and healthy controls (n = 200) using enzyme-linked immunosorbent assay. We further investigated associations between BDNF levels and illness-related variables and medication status.

BDNF levels were found to be 22.0% (95% CI 1.107–1.343) higher in patients with bipolar disorder compared with healthy controls (P < 0.001) and 15.6% higher in unaffected first-degree relatives compared with healthy controls (95% CI 1.007–1.327, P = 0.04), when adjusting for age and gender. Further, BDNF levels were positively associated with duration of illness at a trend level (P = 0.05), age (P = 0.001) and use of anti-epileptic medication (P = 0.05).

These findings suggest that BDNF levels are not decreased in the early stages of bipolar disorder and in unaffected first-degree relatives contrasting with prior findings during later stages of the illness.

Changes in inflammatory and metabolic markers are implicated in the pathogenesis in both the development and progression of bipolar disorder (BD). Notwithstanding, these markers have not been investigated in newly diagnosed BD.

We compared high-sensitive C-reactive protein (hs-CRP) and homocysteine (Hcy) levels in 372 patients with newly diagnosed BD, 106 unaffected first-degree relatives (URs), and 201 healthy control persons (HCs). Within the patient group, we also investigated possible associations between hs-CRP and Hcy, respectively, with illness-related characteristics and psychotropic medication.

No statistically significant differences in Hcy and hs-CRP levels were found when comparing BD and URs with HCs. Similarly, there were no differences when comparing only patients in remission or patients with affective symptoms, respectively, with HCs. Hcy levels were found to be 11.9% (95% CI: 1.030–1.219) higher in patients with BD when compared with their URs (p = 0.008), when adjusting for folate and cobalamin status, age, sex, and self-reported activity levels. Hcy levels were significantly associated with folate, cobalamin, gender, and age in all models (p < 0.05).

Our results do not support hs-CRP or Hcy as markers in newly diagnosed BD.

Depressive episodes experienced in unipolar (UD) and bipolar (BD) disorders are characterized by anhedonia and have been associated with abnormalities in reward processes related to reward valuation and error prediction. It remains however unclear whether these deficits are associated with familial vulnerability to mood disorders.

In a functional magnetic resonance imaging study, we evaluated differences in the expected value (EV) and reward prediction error (RPE) signals in ventral striatum (VS) and prefrontal cortex between three groups of monozygotic twins: affected twins in remission for either UD or BD (n = 53), their high-risk unaffected co-twins (n = 34), and low-risk twins with no family history of mood disorders (n = 25).

Compared to low-risk twins, affected twins showed lower EV signal bilaterally in the frontal poles and lower RPE signal bilaterally in the VS, left frontal pole and superior frontal gyrus. The high-risk group did not show a significant change in the EV or RPE signals in frontostriatal regions, yet both reward signals were consistently lower compared with low-risk twins in all regions where the affected twins showed significant reductions.

Our findings strengthen the notion that reduced valuation of expected rewards and reduced error-dependent reward learning may underpin core symptom of depression such as loss of interest in rewarding activities. The trend reduction in reward-related signals in unaffected co-twins warrants further investigation of this effect in larger samples and prospective follow-up to confirm possible association with increased familial vulnerability to mood disorders.

Aberrant emotional reactivity is a putative endophenotype for bipolar disorder (BD), but the findings of behavioral studies are often negative due to suboptimal sensitivity of the employed paradigms. This study aimed to investigate whether visual gaze patterns and facial displays of emotion during emotional film clips can reveal subtle behavioral abnormalities in remitted BD patients.

Thirty-eight BD patients in full or partial remission and 40 healthy controls viewed 7 emotional film clips. These included happy, sad, and neutral scenarios and scenarios involving winning, risk-taking, and thrill-seeking behavior of relevance to the BD phenotype. Eye gaze and facial expressions were recorded during the film clips, and participants rated their emotional reactions after each clip.

BD patients showed a negative bias in both facial displays of emotion and self-rated emotional responses. Specifically, patients exhibited more fearful facial expressions during all film clips. This was accompanied by less positive self-rated emotions during the winning and happy film clips, and more negative emotions during the risk-taking/thrill-related film clips.

These findings suggest that BD is associated with trait-related abnormalities in subtle behavioral displays of emotion processing. Future studies comparing patients with BD and unipolar depression are warranted to clarify whether these differences are specific to BD. If so, assessments of visual gaze and facial displays of emotion during emotional film clips may have the potential to be implemented in clinical assessments to aid diagnostic accuracy.

Recent evidence suggests that neurocognitive impairments in remitted patients with bipolar disorder (BD) are heterogeneous. Our study aims to replicate recent findings of neurocognitive subgroups, and further explore whether these are related to impairments in affective cognition, in a large sample of remitted patients recently diagnosed with BD and their unaffected relatives compared to healthy controls (HCs).

Hierarchal cluster analysis was conducted using neurocognitive data from remitted patients with BD (n = 158). Relatives of patients with BD (n = 52) were categorised into groups consistent with their affected relative's cluster assignment. The neurocognitive clusters of patients with BD and relatives, respectively, were compared with HCs (n = 110) in neurocognition and affective cognition (i.e. emotion processing and regulation).

Three discrete neurocognitive clusters were identified in patients with BD: a globally impaired (23.4%), a selectively impaired (31.0%) and a cognitively intact cluster (45.6%). The neurocognitive subgroups differed in affective cognition, with patients categorised as globally impaired exhibited most impairments in facial expression recognition and emotion regulation in social scenarios. First-degree relatives of cognitively impaired patients displayed impaired facial expression recognition but no impairments in non-emotional cognition.

In a clinical sample of remitted patients recently diagnosed with BD 54.4% had either global or selective cognitive impairment, replicating results of previous studies in patients with longer illness duration. The results suggest that patterns of neurocognition are associated with differential impairments in affective cognition. Aberrant affective cognition in relatives of patients categorised as neurocognitively impaired indicates an inherited risk for BD.

Metabolic syndrome (MetS) is associated with reduced life expectancy in patients with affective disorders, however, whether MetS also plays a role before the onset of affective disorder is unknown. We aimed to investigate whether MetS, inflammatory markers or oxidative stress act as risk factors for affective disorders, and whether MetS is associated with increased inflammation and oxidative stress.

We conducted a high-risk study including 204 monozygotic (MZ) twins with unipolar or bipolar disorder in remission or partial remission (affected), their unaffected co-twins (high-risk) and twins with no personal or family history of affective disorder (low-risk). Metabolic Syndrome was ascertained according to the International Diabetes Federation (IDF) criteria. Inflammatory markers and markers of oxidative stress were analyzed from fasting blood and urine samples, respectively.

The affected and the high-risk group had a significantly higher prevalence of MetS compared to the low-risk group (20% v. 15% v. 2.5%, p = 0.0006), even after adjusting for sex, age, smoking and alcohol consumption. No differences in inflammatory and oxidative markers were seen between the three groups. Further, MetS was associated with alterations in inflammatory markers, and oxidative stress was modestly correlated with inflammation.

Metabolic syndrome is associated with low-grade inflammation and may act as a risk factor and a trait marker for affective disorders. If confirmed in longitudinal studies, this suggests the importance of early intervention and preventive approaches targeted towards unhealthy lifestyle factors that may contribute to later psychopathology.

Patients with bipolar disorder (BD) experience persistent impairments in both affective and non-affective cognitive function, which is associated with a worse course of illness and poor functional outcomes. Nevertheless, the temporal progression of cognitive dysfunction in BD remains unclear and the identification of objective endophenotypes can inform the aetiology of BD.

The present study is a cross-sectional investigation of cognitive baseline data from the longitudinal Bipolar Illness Onset-study. One hundred seventy-two remitted patients newly diagnosed with BD, 52 of their unaffected relatives (UR), and 110 healthy controls (HC) were compared on a large battery of behavioural cognitive tasks tapping into non-affective (i.e. neurocognitive) and affective (i.e. emotion processing and regulation) cognition.

Relative to HCs, patients with BD exhibited global neurocognitive deficits (ps < 0.001), as well as aberrant emotion processing and regulation (ps ⩽ 0.011); including decreased emotional reactivity to positive social scenarios, impaired ability to down-regulate positive emotion, as well as a specific deficit in the ability to recognise surprised facial expressions. Their URs also showed a trend towards difficulties identifying surprised faces (p = 0.075). No other differences in cognitive function were found for URs compared to HCs.

Neurocognitive deficits and impairments within emotion processing and regulation may be illness-related deficits of BD that present after illness-onset, whereas processing of emotional faces may represent an early risk marker of BD. However, longitudinal studies are needed to examine the association between cognitive impairments and illness progression in BD.

Recently, the MONARCA I randomized controlled trial (RCT) was the first to investigate the effect of smartphone-based monitoring in bipolar disorder (BD). Findings suggested that smartphone-based monitoring sustained depressive but reduced manic symptoms. The present RCT investigated the effect of a new smartphone-based system on the severity of depressive and manic symptoms in BD.

Randomized controlled single-blind parallel-group trial. Patients with BD, previously treated at The Copenhagen Clinic for Affective Disorder, Denmark and currently treated at community psychiatric centres, private psychiatrists or GPs were randomized to the use of a smartphone-based system or to standard treatment for 9 months. Primary outcomes: differences in depressive and manic symptoms between the groups.

A total of 129 patients with BD (ICD-10) were included. Intention-to-treat analyses showed no statistically significant effect of smartphone-based monitoring on depressive (B = 0.61, 95% CI −0.77 to 2.00, p = 0.38) and manic (B = −0.25, 95% CI −1.1 to 0.59, p = 0.56) symptoms. The intervention group reported higher quality of life and lower perceived stress compared with the control group. In sub-analyses, the intervention group had higher risk of depressive episodes, but lower risk of manic episodes compared with the control group.

There was no effect of smartphone-based monitoring. In patient-reported outcomes, patients in the intervention group reported improved quality of life and reduced perceived stress. Patients in the intervention group had higher risk of depressive episodes and reduced risk of manic episodes. Despite the widespread use and excitement of electronic monitoring, few studies have investigated possible effects. Further studies are needed.

Erythropoietin (EPO) has been suggested to improve metabolism and also cognition, but human studies are scarce. This randomised controlled trial aimed to investigate whether EPO treatment influences body composition and fat and glycated haemoglobin (HbA1c) and fasting glucose, and whether these changes would be associated with previous observed cognitive benefits of EPO.

In total, 84 non-obese patients with treatment-resistant unipolar depression or bipolar disorder in remission were randomised to 8 weekly EPO (40,000 IU) or saline (NaCl 0.9%) infusions in a double-blind, parallel-group design. Patients underwent dual X-ray absorptiometry scans at baseline and week 14 (6 weeks after treatment completion). Cognitive measures were assessed and fasting levels of cholesterol, lipoprotein fractions, triacylglycerides, glucose and HbA1c were obtained at baseline, week 9 and follow-up week 14.

In total, 79 patients had complete pre- and post-treatment data (EPO: N=40, saline: N=39). EPO had no cumulative effect on body composition and markers of fat metabolism. The EPO-treated group exhibited significantly lower HbA1c levels after 8 weeks treatment [F(1, 80)=8.51, p=0.005], however, 6 weeks after treatment termination a significantly higher fasting glucose levels [F(1, 79)=5.85, p=0.02] and HbA1c levels [F(1, 79)=5.85, p=0.02] were seen. The latter increase in HbA1c was further significantly correlated with a better cognitive outcome on verbal memory (r=0.25, p=0.03).

Repeated EPO infusions had no cumulative effect on body composition in this cohort of patients with affective disorders, however, EPO modulated HbA1c and fasting glucose and this was associated with patients’ improvement of verbal memory.

No study has investigated when preventive treatment with lithium should be initiated in bipolar disorder.

To compare response rates among patients with bipolar disorder starting treatment with lithium early v. late.

Nationwide registers were used to identify all patients with a diagnosis of bipolar disorder in psychiatric hospital settings who were prescribed lithium during the period 1995–2012 in Denmark (n = 4714). Lithium responders were defined as patients who, following a stabilisation lithium start-up period of 6 months, continued lithium monotherapy without being admitted to hospital. Early v. late intervention was defined in two ways: (a) start of lithium following first contact; and (b) start of lithium following a diagnosis of a single manic/mixed episode.

Regardless of the definition used, patients who started lithium early had significantly decreased rates of nonresponse to lithium compared with the rate for patients starting lithium later (adjusted analyses: firstv. later contact: P<0.0001; hazard ratio (HR) = 0.87, 95% CI 0.76–0.91; single manic/mixed episodev. bipolar disorder: P<0.0001; HR = 0.75, 95% CI 0.67–0.84).

Starting lithium treatment early following first psychiatric contact or a single manic/mixed episode is associated with increased probability of lithium response.