An exploration of testosterone levels in patients with bipolar disorder

Network analysis of comorbid aggressive behavior and testosterone among bipolar disorder patients: a cross-sectional study

Testosterone has complex effects on psychological traits and behavior; it is associated with social dominance and competition and is a potential human sex pheromone. This study aimed to investigate the associations between testosterone levels, aggressive behavior, and manic symptoms using a network analysis among bipolar disorder (BD) patients in psychiatric emergency departments (PED). Data from January 2021 and March 2022 BD patients in PED were analyzed. Manic symptoms were assessed using the Young Mania Rating Scale (YMRS). Aggression was assessed with subscale of the PANSS scale (PANSS-AG). The undirected network structures of testosterone levels, aggressive behavior, and manic symptoms were estimated, and centrality and bridge centrality indices were examined. Network stability was examined using the case-dropping procedure. The Network Comparison Test (NCT) was conducted to evaluate whether network characteristics differed by gender. We recruited a total of 898 BD patients, with the mean YMRS score as 13.30 ± 9.58. The prevalence of level II aggression was 35.6% (95%CI = 32.5%-38.7%), level III aggression was 29.5% (95%CI = 26.3%-32.6%), and level VI aggression was 7.0% (95%CI = 5.4%-8.8%). The male participants had a mean testosterone level of 391.71 (Standard Deviation (SD):223.39) compared to 36.90 (SD:30.50) for female participants in the whole sample. Through network analysis, "Increased motor activity-energy" emerged as the central symptom, with the highest centrality expected influence, followed by "Emotional Instability" and "Disruptive/aggression behavior". Notably, "Emotional Instability" appeared to be the bridge symptom linking manic symptoms to aggressive behavior. Within the flow network model, "Speech rate and amount" exhibited the strongest positive correlation with testosterone levels, followed closely by "Disruptive/aggression behavior". The constructed network model demonstrated robust stability, with gender showing no significant impact on the structure. In this study, "Increased motor activity-energy" stood out as the most influential symptom, and "Speech rate and amount" acted as the main bridge symptom linking testosterone levels, aggressive behavior, and manic symptoms. Targeting the central and bridge symptoms may improve the outcomes of aggression interventions implemented among BD patients in psychiatric emergency care.

Abnormal expression of long non-coding RNAs RMRP, CTC-487M23.5, and DGCR5 in the peripheral blood of patients with Bipolar disorder

Long non-coding RNAs (lncRNAs) have been recently considered as one of the regulatory mechanisms of the nervous system. Hence, lncRNAs may be considered diagnostic biomarkers for bipolar disorder (BD). We aimed to investigate the expression of RMRP, CTC-487M23.5, and DGCR5 lncRNAs in bipolar patients. The levels of these three lncRNAs were measured in peripheral blood mononuclear cells (PBMCs) of 50 BD patients and 50 healthy subjects by real-time PCR. Moreover, we performed a ROC curve analysis between the gene expression and some clinical features of BD patients. Significant upregulation of RMRP and CTC-487M23.5 and no significant change in levels of DGCR5 was observed in BD individuals compared with controls. Also, we found upregulation of RMRP and downregulation of CTC-487M23.5 and DGCR5 in females with BD. The areas under the ROC curve (AUC) for RMRP and CTC-487M23.5 lncRNAs were 0.80 and 0.61, respectively. There was no significant correlation between the expression of these three lncRNAs and clinical features in PBMCs of BD patients. These results suggest a role for RMRP and CTC-487M23.5 in the pathogenesis of bipolar disorder. Moreover, the peripheral expression of these two lncRNAs might be beneficial as potential biomarkers for BD.

Association between testosterone levels and mood disorders: A minireview

BACKGROUND

Although many studies reported the neuropsychiatric involvement of testosterone (T) levels in the development of mood disorders, its role in this disabling disorder is still not well understood. Therefore, in this review, we aim to summarize the current literature exploring serum testosterone levels in both major depressive disorder (MDD) and bipolar disorder (BD), with particular attention given to the possible causal relationship between pathological mood alterations and T levels.

METHODS

We selected 9 original studies from a bibliographic search on PubMed, excluding studies on hormonal therapy and other psychiatric disorders other than mood disorders.

RESULTS

The results reported by the reviewed studies were conflicting especially with regards to the presence of dysfunctional levels of T in patients with BD. Specifically, while MDD was found to be associated with low levels of T compared to healthy controls (HC), in BD the results were highly heterogeneous, with a mixed picture of reduced, increased or no difference in T levels in BD patients compared to HC.

LIMITATIONS

Studies were highly heterogeneous in terms of samples employed, psychometric scales used for assessing depressive symptoms, T assay methods and therapeutic regimens.

CONCLUSIONS

Overall, T levels were shown to be reduced in both MDD and BD patients, ultimately suggesting that T could be useful as a biomarker in mood disorders and provide guidance for future research.

Sex differences in the blood-brain barrier: Implications for mental health

Prevalence of mental disorders, including major depressive disorder (MDD), bipolar disorder (BD) and schizophrenia (SZ) are increasing at alarming rates in our societies. Growing evidence points toward major sex differences in these conditions, and high rates of treatment resistance support the need to consider novel biological mechanisms outside of neuronal function to gain mechanistic insights that could lead to innovative therapies. Blood-brain barrier alterations have been reported in MDD, BD and SZ. Here, we provide an overview of sex-specific immune, endocrine, vascular and transcriptional-mediated changes that could affect neurovascular integrity and possibly contribute to the pathogenesis of mental disorders. We also identify pitfalls in current literature and highlight promising vascular biomarkers. Better understanding of how these adaptations can contribute to mental health status is essential not only in the context of MDD, BD and SZ but also cardiovascular diseases and stroke which are associated with higher prevalence of these conditions.

Sex hormones and immune system: A possible interplay in affective disorders? A systematic review

BACKGROUND

Sex hormones and the immune system may play a key role in sex differences in affective disorders. The understanding of their interplay may lead to the detection of new sex-specific tailored therapeutic approaches. The aim of this systematic review is to summarise the evidence supporting a possible association between sex hormones and inflammatory biomarkers in people with affective disorders.

METHODS

A systematic search of the literature published until January 2021 was conducted on PubMed database. The initial search identified a total of 1259 studies; 20 studies investigating inflammatory biomarkers and sex hormones in patients exhibiting depressive symptoms were included: 10 studies focused on patients with affective disorders, and 10 studies focused on women in menopause or in the post-partum period exhibiting depressive symptoms.

RESULTS

Testosterone and exogenous female sex hormones may play protective roles through their modulation of the immune system, respectively, in male patients with bipolar disorder and in peri-/post-menopausal women with depression.

LIMITATIONS

The main limitations are the paucity of studies investigating both sex hormones and immune biomarkers, the lack of statistical analyses exploring specifically the association between these two classes of biomarkers, and the great heterogeneity between the participants' samples in the studies.

CONCLUSION

This review highlights the need to investigate the interplay between sex hormones and immune system in affective disorders. The inconsistent or incomplete evidence may be improved by studies in patients with moderate-high inflammatory levels that specifically evaluate the relationship between sex hormones and the immune system.

Proximate and Ultimate Perspectives on Romantic Love

Romantic love is a phenomenon of immense interest to the general public as well as to scholars in several disciplines. It is known to be present in almost all human societies and has been studied from a number of perspectives. In this integrative review, we bring together what is known about romantic love using Tinbergen’s “four questions” framework originating from evolutionary biology. Under the first question, related to mechanisms, we show that it is caused by social, psychological mate choice, genetic, neural, and endocrine mechanisms. The mechanisms regulating psychopathology, cognitive biases, and animal models provide further insights into the mechanisms that regulate romantic love. Under the second question, related to development, we show that romantic love exists across the human lifespan in both sexes. We summarize what is known about its development and the internal and external factors that influence it. We consider cross-cultural perspectives and raise the issue of evolutionary mismatch. Under the third question, related to function, we discuss the fitness-relevant benefits and costs of romantic love with reference to mate choice, courtship, sex, and pair-bonding. We outline three possible selective pressures and contend that romantic love is a suite of adaptions and by-products. Under the fourth question, related to phylogeny, we summarize theories of romantic love’s evolutionary history and show that romantic love probably evolved in concert with pair-bonds in our recent ancestors. We describe the mammalian antecedents to romantic love and the contribution of genes and culture to the expression of modern romantic love. We advance four potential scenarios for the evolution of romantic love. We conclude by summarizing what Tinbergen’s four questions tell us, highlighting outstanding questions as avenues of potential future research, and suggesting a novel ethologically informed working definition to accommodate the multi-faceted understanding of romantic love advanced in this review.

Investigation of second to fourth finger length ratio (2D:4D) in patients with bipolar disorder

Objective:

The etiology of bipolar disorder has yet to be fully elucidated, but differences in sex hormones have been suggested to play a role in its pathogenesis. An easily assessed marker of prenatal androgen exposure is the second-to-fourth-digit ratio (2D:4D) of the hand. In this study, we aimed to compare the 2D:4D ratio of patients with bipolar disorder to that of healthy controls.

Methods:

Seventy patients with bipolar disorder and 70 healthy controls, matched for age and sex, were included in the study. Finger lengths were measured from the palmar digital crease to the tip using a digital vernier caliper.

Results:

Patients with bipolar disorder had considerably higher right-hand 2D:4D ratios compared to controls. Both the right and left 2D:4D ratios of male patients were significantly greater than those of males in the control group. Female patients showed no differences in right or left 2D:4D ratio compared to healthy controls.

Conclusion:

These findings suggest that a high 2D:4D digit ratio of right hand is associated with the presence of bipolar disorder in males. Further large-scale, prospective studies are needed to explain the validity of this marker and its relationship with bipolar disorder.

The Potential Effect of Aberrant Testosterone Levels on Common Diseases: A Mendelian Randomization Study

Testosterone has historically been linked to sexual dysfunction; however, it has recently been shown to affect other physical and mental attributes. We attempted to determine whether changes in serum testosterone could play a role in chronic or degenerative diseases. We used two separate genetic instruments comprising of variants from JMJD1C and SHBG regions and conducted a two-sample Mendelian randomization for type II diabetes (T2D), gout, rheumatoid arthritis (RA), schizophrenia, bipolar disorder, Alzheimer's disease and depression. For the JMJD1C locus, one unit increase in log transformed testosterone was significantly associated with RA (OR = 1.69, p = 0.02), gout (OR = 0.469, p = 0.001) and T2D (OR = 0.769, p = 0.048). Similarly, one unit increase in log transformed testosterone using variants from the SHBG locus was associated with depression (OR = 1.02, p < 0.0001), RA (OR = 1.254, p < 0.0001) and T2D (OR = 0.88, p < 0.0001). Our results show that low levels of serum testosterone levels may cause gout and T2D, while higher than normal levels of testosterone may result in RA and depression. Our findings suggest that fluctuations in testosterone levels may have severe consequences that warrant further investigation.

What is bipolar disorder? A disease model of dysregulated energy expenditure

Advances in the understanding and management of bipolar disorder (BD) have been slow to emerge. Despite notable recent developments in neurosciences, our conceptualization of the nature of this mental disorder has not meaningfully progressed. One of the key reasons for this scenario is the continuing lack of a comprehensive disease model. Within the increasing complexity of modern research methods, there is a clear need for an overarching theoretical framework, in which findings are assimilated and predictions are generated. In this review and hypothesis article, we propose such a framework, one in which dysregulated energy expenditure is a primary, sufficient cause for BD. Our proposed model is centered on the disruption of the molecular and cellular network regulating energy production and expenditure, as well its potential secondary adaptations and compensatory mechanisms. We also focus on the putative longitudinal progression of this pathological process, considering its most likely periods for onset, such as critical periods that challenges energy homeostasis (e.g. neurodevelopment, social isolation), and the resulting short and long-term phenotypical manifestations.

Evaluation of 2D:4D digit ratio in bipolar 1 disorder patients and its relationship with treatment response

BACKGROUND

The role of sex steroids in bipolar disorder (BD) has been demonstrated in adults. We aimed to evaluate the 2D:4D ratio, which indirectly reflects prenatal sex steroids, in BD. Another purpose of this study was to determine the relationship between clinical features, especially lithium response, and digit ratio.

METHODS

The study included 74 patients with bipolar 1 disorder and 74 healthy individuals matched according to age, gender, and educational status. The digit ratio was calculated by dividing the index finger (2D) length by the ring finger (4D) length in both hands. A lithium response scale was used to evaluate the lithium response history.

RESULTS

There was no difference in 2D:4D ratio between the patients and controls in either right or left hands. The digit ratio was not different between groups with and without suicide attempts. The 2D:4D ratio in the patient group was lower in individuals unresponsive to lithium therapy than in partial and good responders for both right and left hands.

DISCUSSION

According to the results of our study, the 2D:4D ratio in the BD group was not different from healthy controls but was lower in patients unresponsive to lithium. In this respect, the 2D:4D ratio can be considered as a biomarker for lithium response in BD. In large-sample studies, the 2D:4D ratio should be investigated for pathophysiology and treatment response of BD.

Serum testosterone levels in bipolar and unipolar depressed female patients and the role of medication status

Objective: to compare testosterone levels between female depressed patients and female bipolar patients.Methods: Sixty-one female patients with major depressive disorder (MDD) (n = 23) or bipolar disorder (BD) (n = 38) between 18 and 45 years old were included in the study. Participants were evaluated during a depressive or manic episode with the Hamilton depression rating scale (HDRS) or Young mania rating scale (YMRS), respectively. No patients in the MDD group were taken valproate while in the BD group 14 (36.84%) were taken valproate. Total testosterone (TT) and free testosterone (FT) levels were quantified during the early follicular phase of the cycle, with radioimmunoassay or solid phase enzyme-linked immunoassay. Data were collected from May 2016 to February 2017.Results: Mean TT serum levels were significantly higher in BD patients in comparison to MDD patients. Although age and diagnosis were related to TT levels, however when we added valproate use in the analysis, only the relation between TT and valproate use remained significant.Conclusions: In this sample, TT levels were related to valproate use in patients with BD. More studies regarding the role of testosterone in affective symptoms should be conducted to clarify the relation between testosterone, affective disorders, and medication.KeypointsWe observed that testosterone levels were significant higher in bipolar women compared to women with MDD.The use of valproate could be associated with the testosterone levels in female patients with BD.Evaluation of women suffering BD should include a testosterone levels determination, particularly when they are taking valproate.

Sex differences in schizophrenia, bipolar disorder, and post-traumatic stress disorder: Are gonadal hormones the link?

In this review, we describe the sex differences in prevalence, onset, symptom profiles, and disease outcome that are evident in schizophrenia, bipolar disorder, and post-traumatic stress disorder. Women with schizophrenia tend to exhibit less disease impairment than men. By contrast, women with post-traumatic stress disorder are more affected than men. The most likely candidates to explain these sex differences are gonadal hormones. This review details the clinical evidence that oestradiol and progesterone are dysregulated in these psychiatric disorders. Notably, existing data on oestradiol, and to a lesser extent, progesterone, suggest that low levels of these hormones may increase the risk of disease development and worsen symptom severity. We argue that future studies require a more inclusive, considered analysis of gonadal steroid hormones and the intricacies of the interactions between them, with methodological rigour applied, to enhance our understanding of the roles of steroid hormones in psychiatric disorders. LINKED ARTICLES: This article is part of a themed section on The Importance of Sex Differences in Pharmacology Research. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.21/issuetoc.

Evidence for enhanced androgen action in the prefrontal cortex of people with bipolar disorder but not schizophrenia or major depressive disorder

Anxiety and depressive disorders are more prevalent in hypogonadal men. Low testosterone levels are associated with greater negative symptoms and impaired cognition in men with schizophrenia. Thus, androgens may contribute to brain pathophysiology in psychiatric disorders. We investigated androgen-related mRNAs in post-mortem dorsolateral prefrontal cortex of psychiatric disorders. We also assessed androgen receptor (AR) CAG trinucleotide repeat length, a functional AR gene variant associated with AR gene expression, receptor activity, and circulating testosterone. AR CAG repeat length was determined from genomic DNA and AR and 5α-reductase mRNAs measured using quantitative PCR in schizophrenia, bipolar disorder and control cases [n = 35/group; Stanley Medical Research Institute (SMRI) Array collection]. Layer-specific AR gene expression was determined using in situ hybridisation in schizophrenia, bipolar disorder, major depressive disorder and control cases (n = 15/group; SMRI Neuropathology Consortium). AR mRNA was increased in bipolar disorder, but was unchanged in schizophrenia, relative to controls. AR and 5α-reductase mRNAs were significantly positively correlated in bipolar disorder. AR CAG repeat length was significantly shorter in bipolar disorder relative to schizophrenia. AR mRNA expression was highest in cortical layers IV and V, but no layer-specific diagnostic differences were detected. Together, our results suggest enhanced cortical androgen action in people with bipolar disorder.

Newly Diagnosed Bipolar Disorder and the Subsequent Risk of Erectile Dysfunction: A Nationwide Cohort Study

BACKGROUND

Although erectile dysfunction (ED) is a common problem in men with mental disorders, there are few reports in the literature on the relation between bipolar disorder (BD) and ED.

AIMS

To establish the incidence rate of ED in men with BD and assess the risk of ED in patients with BD according to type of treatment offered or no active treatment with medication during the 1st year of onset.

METHODS

We identified 5,150 men with newly diagnosed BD using Taiwan's National Health Insurance Research Database. 2 matched controls per case were selected using the propensity score and a greedy matching method to obtain a balanced control group. Multivariate Cox regression analysis was used to examine the independent risk factors for ED, including obesity and comorbidities. Hazard ratios (HRs) for ED risk were calculated for the different psychotropic therapy groups, including antidepressants, antipsychotics, and mood stabilizers.

OUTCOME

HRs for ED risk were calculated for the different psychotropic therapy groups, including antidepressants, antipsychotics, and mood stabilizers. Patients with BD had a significantly higher HR for an ED diagnosis than controls.

RESULTS

Patients with BD had a higher HR for an ED diagnosis than controls. Although some psychotropic medications can increase the risk of ED, patients with BD not actively treated with medication still showed a higher risk of ED than controls.

CLINICAL IMPLICATIONS

Because ED might be more prevalent in patients with BD than in the general population, clinicians should assess erectile function when selecting appropriate treatment for patients with BD to minimize the risk of ED as an annoying side effect and improve treatment compliance.

STRENGTHS AND LIMITATIONS

This is the first large-scale population-based study to explore the association between BD and ED. A particular strength of this study is its nationwide, population-based study design, which afforded substantial statistical power for detecting subtle differences between the 2 cohorts, thereby minimizing selection bias. There are some limitations to the present study. (i) Data on other potential risk factors is lacking. (ii) Patient compliance and dose effect between psychotropic medication and ED could not be established. (iii) We could not assess the relation between ED and the severity and phases of BD.

CONCLUSION

This cohort study found a temporal association between BD and subsequent ED in a large national sample of men. Clinicians should consider the risk of ED when choosing treatment for patients with BD. Hou P-H, Mao FC, Chang G-R, et al. Newly Diagnosed Bipolar Disorder and the Subsequent Risk of Erectile Dysfunction: A Nationwide Cohort Study. J Sex Med 2018;15:183-191.

Comparison of salivary testosterone levels in different phases of bipolar I disorder and control group

Background:

Testosterone is considered as a primary sex hormone, also known as an important anabolic steroid, that may involve in various mental disorders such as bipolar I disorder (BID). The goal of this study was to compare the testosterone salivary levels between different phases of BID and its association with the clinical features of BID.

Materials and Methods:

In a case–control study, 15 patients in the mania phase, 10 patients in the depression phase, and 16 in the euthymia phase were selected as patient groups. 18 healthy sex- and age-matched individuals were considered as healthy control group. Salivary samples obtained from all patients and control group and levels of testosterone were determined in saliva using an enzyme-linked immunosorbent assay. All statistical calculations were conducted with the software Statistical Package for Social Science version 20 (IBM Inc., Chicago, IL, USA).

Results:

The mean testosterone level in euthymia phase was 186.34 ± 182.62 pg/mL, mania phase was 239.29 ± 273.22 pg/mL, depression was 153.49 ± 222.50 pg/mL, and healthy participants was 155.73 ± 126.0 pg/mL; no significant difference was found between groups (P = 0.68.(No statistically significant differences were found between psychotic and nonpsychotic as well as between patients who attempted suicide and nonattempter patients in terms of testosterone levels (P > 0.1).

Conclusion:

Our findings do not reveal significant difference between different phases of BID in terms of salivary testosterone levels. However, more comprehensive studies with larger sample size are required to confirm our findings.

Serum lithium levels and suicide attempts: a case-controlled comparison in lithium therapy-naive individuals

BACKGROUND

Several epidemiological studies have shown the inverse association of lithium levels in drinking water and suicide rates; however, it is necessary to perform a clinical study dealing with individual patients.

METHODS

We analyzed 199 patients including 31 patients with suicide attempts, 21 patients with self-harm, and 147 control patients. All were transferred to a university emergency department suffering from intoxication or injury, were aged 20 or more years, and were alive at the start of the study. The exclusion criteria consisted of suffering from schizophrenia and a past or present history of lithium therapy. These exclusions were applied because it is difficult to determine whether their suicide attempt was induced by the intent to end their life or by psychotic symptoms such as auditory hallucinations, and if the patient had received lithium therapy, the association between the small amount of lithium taken from drinking water and food and serum lithium levels cannot be detected.

RESULTS

There was a significant difference (p = 0.043) between the three groups whereby patients with suicide attempts had significantly lower lithium levels than control patients (p = 0.012) in males but not females. Multivariate logistic regression analysis with adjustment for age and gender revealed that patients with suicide attempts had significantly lower lithium levels than control patients (p = 0.032, odds ratio 0.228, 95% CI 0.059-0.883).

LIMITATIONS

The limitations of the present study are the nature of observational research which cannot reveal a causal relationship and the relatively small number of subjects.

CONCLUSIONS

The present findings suggest that higher serum lithium levels may be protective against suicide attempts in lithium therapy-naive individuals.