Clinical correlates of age at onset distribution in bipolar disorder: a comparison between diagnostic subgroups

Characterization of Bipolar Disorder I and II: Clinical Features, Comorbidities, and Pharmacological Pattern

Objective

Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition provides precise diagnostic criteria to differentiate between bipolar disorder (BD) type I and II; nevertheless, it can be challenging to come up with the right diagnosis. The aim of this study is to evaluate the sociodemographic differences, clinical features, comorbidities, and pharmacological pattern between patients with BD type I and II.

Methods

A total of 680 patients with BD type I and II were consecutively recruited to our psychiatry department. A semi-structured interview was used to collect several information.

Results

Patients with BD type I were mostly males, single, with a lower current age, and unemployed compared to patients with BD type II. Furthermore, patients with BD type I showed an earlier age at onset and a significant higher prevalence of psychotic and residual symptoms, a higher number of hospitalizations, and involuntary admissions. On the other hand, patients with BD type II were associated with a significant higher prevalence of lifetime suicide attempts, psychiatric comorbidities, and use of alcohol. Finally, antidepressant drugs were prescribed more often to patients with BD type II, while antipsychotics and mood stabilizers were mostly prescribed in patients with BD type I.

Conclusion

the differentiation of the 2 nosologic bipolar diagnosis is in line with the current scientific interest, confirming the existence of a markedly different profile between BD type I and II. This differentiation could reduce the heterogeneity of bipolar presentation in research, optimize clinical assessment, and increase the interest in developing more precise and individualized therapeutic strategies, also implementing psychosocial therapies.

Longitudinal changes in resting-state functional connectivity as markers of vulnerability or resilience in first-degree relatives of patients with bipolar disorder

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Telomere length as a modifier in the relationship between phthalate metabolites exposure and glucose homeostasis

Given the rising concern over the potential impact of environmental factors on metabolic heath, we conducted a cross-sectional analysis among 645 adults aged 20 and older in the National Health and Nutrition Examination Survey (NHANES), examining the association between nine phthalate metabolites (Mono-n-butyl phthalate (MBP), Mono-ethyl phthalate (MEP), Mono-(2-ethyl)-hexyl phthalate (MEHP), Mono-benzyl phthalate (MBzP), Mono-n-methyl phthalate (MnMP), Mono-(3-carboxy propyl) phthalate (MCPP), Mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), Mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), Mono-isobutyl phthalate (MiBP)) and six glucose homeostasis indices (fasting glucose, fasting insulin, hemoglobin A1C (HbA1C), homeostatic model assessment of insulin resistance (HOMA-IR), single Point Insulin Sensitivity Estimator (SPISE), and HOMA-β). Latent Class Analysis identified three phthalate metabolites exposure patterns: high MEP-low MEOHP (n = 282), high MBzP-low MEHHP (n = 214), and high MEHHP, MEOHP (n = 149). The high MBzP-low MEHHP and high MEHHP, MEOHP, versus the high MEP-low MEOHP, exposure groups showed significantly higher levels of fasting insulin (β = 0.126, 95% CI: 0.023-0.228), SPISE (β = 0.091, 95% CI: 0.018-0.164), and HOMA-IR (β = 0.091, 95% CI: 0.018-0.164). In the shorter telomere length group, high MEHHP, MEOHP exposure showed an increase in SPISE levels (β = 0.153, 95% CI: 0.037-0.269), while in the overweight/obese subgroup, high MEHHP, MEOHP exposure was significantly positively associated with HOMA-IR (β = 0.392, 95% CI: 0.150-0.735). Bayesian kernel machine regression analyses showed positive associations between higher combined phthalate exposure and increased glucose homeostasis indices (fasting glucose, HbA1C, fasting insulin, SPISE, and HOMA-IR). The quantile of g-calculation analysis also supported the positive associations with HbA1C, HOMA-IR, and fasting insulin. Our findings indicate that phthalate exposure was positively associated with glucose homeostasis indices, which strengthen the call for proactive measures to reduce phthalate exposure and mitigate potential risks to glucose metabolism.

Characterisation of age and polarity at onset in bipolar disorder

BACKGROUND

Studying phenotypic and genetic characteristics of age at onset (AAO) and polarity at onset (PAO) in bipolar disorder can provide new insights into disease pathology and facilitate the development of screening tools.

AIMS

To examine the genetic architecture of AAO and PAO and their association with bipolar disorder disease characteristics.

METHOD

Genome-wide association studies (GWASs) and polygenic score (PGS) analyses of AAO (n = 12 977) and PAO (n = 6773) were conducted in patients with bipolar disorder from 34 cohorts and a replication sample (n = 2237). The association of onset with disease characteristics was investigated in two of these cohorts.

RESULTS

Earlier AAO was associated with a higher probability of psychotic symptoms, suicidality, lower educational attainment, not living together and fewer episodes. Depressive onset correlated with suicidality and manic onset correlated with delusions and manic episodes. Systematic differences in AAO between cohorts and continents of origin were observed. This was also reflected in single-nucleotide variant-based heritability estimates, with higher heritabilities for stricter onset definitions. Increased PGS for autism spectrum disorder (β = -0.34 years, s.e. = 0.08), major depression (β = -0.34 years, s.e. = 0.08), schizophrenia (β = -0.39 years, s.e. = 0.08), and educational attainment (β = -0.31 years, s.e. = 0.08) were associated with an earlier AAO. The AAO GWAS identified one significant locus, but this finding did not replicate. Neither GWAS nor PGS analyses yielded significant associations with PAO.

CONCLUSIONS

AAO and PAO are associated with indicators of bipolar disorder severity. Individuals with an earlier onset show an increased polygenic liability for a broad spectrum of psychiatric traits. Systematic differences in AAO across cohorts, continents and phenotype definitions introduce significant heterogeneity, affecting analyses.

Early age of onset of mood, anxiety and alcohol use disorders is associated with sociodemographic characteristics and health outcomes in adults: results from a cross-sectional national survey

PURPOSE

This cross-sectional study investigated distribution, sociodemographic correlates, and health outcomes in early versus late age of onset (AOO) of mood, anxiety, and alcohol use disorders in Singapore.

METHODS

The Composite International Diagnostic Interview established lifetime diagnoses of major depressive, bipolar, generalized anxiety, obsessive compulsive and alcohol use disorders in a representative sample of residents aged 18 years and over (n = 6126). The AOO of the individual and any mental disorders were classified into early and late onset using median values as cut-offs. Data included socio-demographic and health background, health utility score, and productivity losses. Multivariable logistic regression analysis was conducted to assess sociodemographic correlates of early versus late AOO of any mental disorder while linear regression analysis investigated the associations between AOO of individual disorders with health utility score and productivity loss.

RESULTS

Respondents' mean (SD) age was 45.6 (16.5) years, comprising 50.5% women and majority of Chinese ethnicity (75.8%). The median AOO for any of the five studied disorders was 21 years (IQR: 15-29). Lowest AOO was observed for obsessive compulsive disorder (Median: 14, IQR: 11-26). Those aged 35 years and over (versus 18-34) were less likely to have earlier AOO [35-49 years (OR: 0.287; 95% CI: 0.154-0.534); 50-64 years (OR:0.156; 95% CI: 0.068-0.361) and 65 and over (OR:0.112; 95% CI:0.027-0.461)], while Malay ethnicity (versus Chinese) (OR: 2.319; 95% CI: 1.384-3.885) and being never married (versus married) (OR: 2.731; 95% CI: 1.493-4.993) were more likely to have early AOO for any mental disorder. Sample with early (versus late) AOO had a lower health utility score (β =  - 0.06,95% CI: - 0.08 to - 0.03) and higher number of days cut down on the type of work (β = 1.61,95% CI: 0.12-3.10) in those with any mental disorders.

CONCLUSION

This study showed that half of the adults with mood, anxiety or alcohol use disorders in Singapore experienced their illness onset by 21 years of age. Early AOO is associated with sociodemographic background and poor health outcomes. Prevention, early detection, and interventions to improve health outcomes in mental disorders should consider the sociodemographic profile and age at first onset of symptoms in the population.

Social support in patients with bipolar disorder and differing ages at onset

OBJECTIVE

The main purpose of this study was to evaluate the association between age at onset and social support in outpatients with bipolar disorder who were in the recovery phase. We also investigated the association between age at onset and disability.

METHODS

A total of 180 bipolar disorder I outpatients, of whom 50 had early onset with age at onset ≤18 years old, 108 had middle onset with age at onset between 19 and 39 years old, and 22 had late onset with age at onset ≥40 years old, were assessed with the Medical Outcomes Study Social Support Scale and Sheehan Disability Scale.

RESULTS

The early onset group had lower tangible social support, longer length of illness, more childless participants, lower income and more suicide attempters than the late onset group.

CONCLUSIONS

Early onset seems to have inferior outcomes in tangible social support than late onset, but this trend should be considered as a starting point for future studies.

Predominant Polarity and Polarity Index of Maintenance Treatments for Bipolar Disorder: A Validation Study in a Large Naturalistic Sample in Italy

Background and Objectives: Predominant polarity (PP) may be a useful course specifier in at least a significant proportion of patients with Bipolar Disorder (BD), being associated with several clinically relevant correlates. Emerging evidence suggests that the concept of PP might influence the selection of maintenance treatments, based on a drug polarity index (PI) which measures the greater antidepressive vs. antimanic preventive efficacy of mood stabilizers over long-term maintenance treatment. In this study, we aimed to validate the PI in a large sample of Italian BD patients with accurate longitudinal characterization of the clinical course, which ensured a robust definition of the PP. Materials and Methods: Our sample is comprised of 653 patients with BD, divided into groups based on the predominant polarity (manic/hypomanic predominant polarity—MPP, depressive predominant polarity—DPP and no predominant polarity). Subsequently we calculated the mean total polarity index for each group, and we compared the groups. Results: When we examined the mean PI of treatments prescribed to individuals with DPP, MPP and no predominant polarity, calculated using two different methods, we failed to find significant differences, with the exception of the PI calculated with the Popovic method and using the less stringent criterion for predominant polarity (PP_50%). Conclusions: Future prospective studies are needed in order to determine whether the predominant polarity is indeed one clinical factor that might guide the clinician in choosing the right mood stabilizer for BD maintenance treatment.

Bipolar disorder: Trimodal age-at-onset distribution

OBJECTIVE

Bipolar disorder (BD) is a chronic mental health disorder with significant morbidity and mortality. Age at onset (AAO) may be a key variable in delineating more homogeneous subgroups of BD patients. However, no known research has systematically assessed how BD age-at-onset subgroups should be defined.

METHODS

We systematically searched the following databases: Cochrane Central Register of Controlled Trials, PsycINFO, MEDLINE, Embase, CINAHL, Scopus, Proquest Dissertations and Theses, Google Scholar and BIOSIS Previews. Original quantitative English language studies investigating AAO in BD were sought.

RESULTS

A total of 9454 unique publications were identified. Twenty-one of these were included in data analysis (n = 22981 BD participants). Fourteen of these studies (67%, n = 13626 participants) found a trimodal AAO distribution: early-onset (µ = 17.3, σ = 1.19, 45% of sample), mid-onset (µ = 26.0, σ = 1.72, 35%), and late-onset (µ = 41.9, σ = 6.16, 20%). Five studies (24%, n = 1422 participants) described a bimodal AAO distribution: early-onset (µ = 24.3, σ = 6.57, 66% of sample) and late-onset (µ = 46.3, σ = 14.15, 34%). Two studies investigated cohort effects on BD AAO and found that when the sample was not split by cohort, a trimodal AAO was the winning model, but when separated by cohort a bimodal distribution fit the data better.

CONCLUSIONS

We propose that the field conceptualises bipolar disorder age-at-onset subgroups as referring broadly to life stages. Demarcating BD AAO groups can inform treatment and provide a framework for future research to continue to investigate potential mechanisms of disease onset.

Developmental trajectories in psychiatric disorders: does substance/alcohol use moderate the effects of affective temperaments as moderators of age at onset? A study in post-acute, hospitalized patients with psychotic or DSM-5 bipolar or major depressive disorders

BACKGROUND

Age-at-onset (AAO) affects psychiatric disorder outcome; substance (SUDs) or alcohol use disorders (AUDs) may influence their onset. Affective temperaments may affect early AAO and drug-use proneness. Objectives: To investigate whether SUD/AUD moderated temperamental effects in determining AAO of mental disorders. Methods: We included 300 post-acute inpatients with schizophrenia-spectrum and other psychotic (SSOPDs), major depressive (MDD) or bipolar (BD) disorders (168 men; mean age, 40.63 years ± 11.82 men, 43.21 years ± 12.69 women) with (N = 110) or without (N = 190) SUD/AUD. Patients completed cross-sectionally TEMPS-A. We carried moderation analysis with each regression-significant TEMPS temperament as independent variable, SUD/AUD presence/absence as dichotomous moderator, and AAO as dependent variable. Significance was set at p < 0.05. Results: AAO was lower in patients with SUD/AUD diagnosis than in patients without (23.74 ± 10.09 vs. 27.73 ± 10.35, respectively, p = 0.001, η2 = 0.034). SUD/AUD patients scored higher on the hyperthymic (10.22 ± 4.08, p < 0.001, η2 = 0.069) and irritable (8.26 ± 4.69, p < 0.01, η2 = 0.026) temperaments than nonSUD/AUD patients. Moderation analysis showed only direct effects of irritable (β = -0.55, p < 0.005) and hyperthymic (β = -0.95, p < 0.001) temperaments on AAO and no significant SUD/AUD and interaction effects. Limitations. Cross-sectional design. Conclusions: When irritable and hyperthymic traits prevail over other temperaments, AAO is earlier in SSOPDs, MDD, and BD. SUD/AUD presence/absence does not moderate the relationship between temperament and AAO.

Translating big data to better treatment in bipolar disorder - a manifesto for coordinated action

Bipolar disorder (BD) is a major healthcare and socio-economic challenge. Despite its substantial burden on society, the research activity in BD is much smaller than its economic impact appears to demand. There is a consensus that the accurate identification of the underlying pathophysiology for BD is fundamental to realize major health benefits through better treatment and preventive regimens. However, to achieve these goals requires coordinated action and innovative approaches to boost the discovery of the neurobiological underpinnings of BD, and rapid translation of research findings into development and testing of better and more specific treatments. To this end, we here propose that only a large-scale coordinated action can be successful in integrating international big-data approaches with real-world clinical interventions. This could be achieved through the creation of a Global Bipolar Disorder Foundation, which could bring government, industry and philanthropy together in common cause. A global initiative for BD research would come at a highly opportune time given the seminal advances promised for our understanding of the genetic and brain basis of the disease and the obvious areas of unmet clinical need. Such an endeavour would embrace the principles of open science and see the strong involvement of user groups and integration of dissemination and public involvement with the research programs. We believe the time is right for a step change in our approach to understanding, treating and even preventing BD effectively.

Clinical Severity and Calcium Metabolism in Patients with Bipolar Disorder

Parathyroid hormone (PTH), vitamin D and serum calcium play a key role in several physiological and pathological conditions. Vitamin D and PTH receptors are largely expressed in the central nervous system and are involved in the modulation of inflammatory responses. Few studies investigated the association between calcium homeostasis imbalance and psychiatric disorders. This study aims to assess calcium homeostasis imbalance in patients with bipolar disorder (BD) and its impact on clinical outcome. We recruited 199 patients with BD, who were administered with validated assessment instruments to investigate depressive, manic and anxiety symptoms, affective temperaments, childhood trauma and global functioning. Serum calcium, vitamin D and PTH levels were assessed in all patients. Levels of PTH correlated with several clinical characteristics, including the diagnosis of bipolar disorder type I (BD-I), the presence of psychotic symptoms, lithium treatment, suicidality, total number of acute episodes and of hospitalizations (p < 0.0001) and seasonality (p < 0.05). At the regression analyses, higher levels of PTH were predicted by early age at onset, number of hospitalizations, aggressive behaviors (p < 0.05), higher Childhood Trauma Questionnaire total score (CTQ) (p < 0.001) and treatment with lithium (p = 0.01). Our findings suggest that the calcium homeostasis could play a role in BD patients, and that PTH levels are correlated with the clinical severity of the disorder.

Comparisons of the clinical outcomes between early- and adult-onset bipolar disorders: A prospective cohort analysis

BACKGROUND

This study aimed to explore the impact of age-at-onset on clinical outcomes in bipolar-spectrum disorders, including the development of alcohol or substance use disorder, suicidality, and psychiatric hospitalization.

METHODS

This population-based study enrolled newly-diagnosed bipolar-spectrum patients, including 4,367 patients with early-onset bipolar disorder (EOBD), 64,787 patients with adult-onset bipolar disorder (AOBD), and the same number of age-controlled comparison subjects without bipolar disorder, from Taiwan's National Health Insurance Research Database. Time-dependent covariate Cox regression models were used to estimate the effect of age-at-onset on clinical outcomes with adjustment for pre-existing psychiatric comorbid conditions and pharmacological treatment patterns. Sensitivity analyses using different definitions of study sample and age cutoffs were conducted.

RESULTS

The average follow-up duration was 5.7 years. After adjustment with time-dependent covariates and chronological age, there were no significant differences in the risks for developing new-onset alcohol or substance use disorders and psychiatric hospitalization between EOBD and AOBD patients. Although EOBD patients had a higher risk of hospitalization for suicide and self-harm than did AOBD patients in primary analysis, this finding did not replicated in the sensitivity analyses.

LIMITATIONS

The symptom profile and severity of bipolar disorder was not available in the NHIRD; therefore, surrogate indicators of clinical outcome might not be sensitive enough to detect the subtle differences.

CONCLUSIONS

EOBD and AOBD patients had similar risks for developing alcohol or substance use disorders. Their risk of psychiatric hospitalization was similar. Whether EOBD patients might have a higher risk of hospitalization for suicide and self-harm warrants further investigations.

Cannabis Use and Hypomania in Young People: A Prospective Analysis

BACKGROUND

Cannabis use in young people is common and associated with psychiatric disorders. However, the prospective link between cannabis use and bipolar disorder symptoms has rarely been investigated. The study hypothesis was that adolescent cannabis use is associated with hypomania in early adulthood via several potential etiological pathways.

METHODS

Data were used from the Avon Longitudinal Study of Parents and Children, a UK birth cohort study. The prospective link between cannabis use at age 17 and hypomania at age 22-23 years was tested using regression analysis, adjusted for gender, early environmental risk factors, alcohol and drug use, and depression and psychotic symptoms at age 18 years. Path analysis examined direct and indirect effects of the link and whether gender, childhood family adversity, or childhood abuse are associated with hypomania via an increased risk of cannabis use.

RESULTS

Data were available on 3370 participants. Cannabis use at least 2-3 times weekly was associated with later hypomania (OR = 2.21, 95% CI = 1.49-3.28) after adjustment. There was a dose-response relationship (any use vs weekly). Cannabis use mediated the association of both childhood sexual abuse and hypomania, and male gender and hypomania. The cannabis use-hypomania link was not mediated by depression or psychotic symptoms.

CONCLUSIONS

Adolescent cannabis use may be an independent risk factor for future hypomania, and the nature of the association suggests a potential causal link. Cannabis use mediates the link between childhood abuse and future hypomania. As such it might be a useful target for indicated prevention of hypomania.

White Matter Microstructural Changes and Episodic Memory Disturbances in Late-Onset Bipolar Disorder

Background: Bipolar disorder (BD) has been associated with distributed network disruption, but little is known on how different clinical subtypes, particularly those with an earlier and later onset of disease, are related to connectivity changes in white matter (WM) tracts. Methods: Diffusion tensor imaging (DTI) and volumetric measures were carried out in early-onset bipolar patients [(EOD) (n = 16)], late-onset bipolar disorder [(LOD)(n = 14)] and healthy controls (n = 32). We also computed ROI analysis of gray matter (GM) and white matter (WM) volumes using the regions with significant group differences in the DTI parameters. Cognitive and behavior measurements were analyzed between groups. Results: Lower fraction of anisotropy (FA) in the right hemisphere comprising anterior thalamic radiation, fornix, posterior cingulate, internal capsule, splenium of corpus callosum was observed in the LOD in comparison with EOD; additionally, lower FA was also found in the LOD in comparison with healthy controls, mostly in the right hemisphere and comprising fibers of the splenium of the corpus callosum, cingulum, superior frontal gyrus and posterior thalamic radiation; LOD also showed worse episodic memory performance than EOD; no statistical significant differences between mood symptoms, WM and GM volumes were found between BD groups. Conclusion: Even after correcting for age differences, LOD was associated with more extensive WM microstructural changes and worse episodic memory performance than EOD; these findings suggest that changes in the WM fiber integrity may be associated with a later presentation of BD, possibly due to mechanisms other than neuroprogression. However, these findings deserve replication in larger, prospective, studies.