Bipolar disorder in an evolutionary framework: rethinking adaptation, vulnerability, and stigma

susceptibility, the combined polygenic signal of common variants accounts for 25% of the genetic variance in BD. Furthermore, 70% of this variance is shared with schizophrenia (33). From an evolutionary perspective, the highly polygenic architecture of bipolar disorder may also be interpreted as compatible with models of balancing selection acting on temperamental traits within the population. Rather than reflecting a single pathogenic pathway, the presence of numerous common variants with small individual effects may represent the genetic substrate of behavioral diversity, including traits related to energy regulation, novelty seeking, creativity, and social drive. In this context, the partial genetic overlap observed between bipolar disorder and other psychiatric conditions may not solely indicate shared vulnerability, but could also reflect the evolutionary maintenance of variation in psychological and behavioral traits that may confer advantages in certain environmental or social contexts. This may reflect a shared genetic vulnerability contributing to both bipolar disorder and schizophrenia (34,35). Furthermore, alternative hypotheses have also been proposed (36,37). The large number of genetic variants associated with bipolar disorder, each contributing a small effect, highlights the complex and heterogeneous biological architecture of the condition (38).1) Given that the disorder is defined on a descriptive syndromic basis, it is possible that different etiopathogenetic pathways lead to similar symptoms (39).2) Within these different etiopathogenetic pathways, it is possible that the emergence of epiphenomena worthy of clinical relevance is also the result of the encounter between predisposing factors, including genetics, that may become pathological in interaction with the environment, especially in the most vulnerable stages of life (40).This perspective is also linked to the evidence that the prevalence of mood disorders is at least stable in the population over time, but with some evidence of an increase in the last decades in the United States (41), New South Wales (42), and Korea (43). Multiple studies hypothesize that the persistence of prevalence may relate to the fact that some aspects of bipolar spectrum disorders may offer advantages in areas such as creativity and inventiveness (44)(Fig. 1). It is important to distinguish between different levels of expression within the bipolar spectrum when discussing potential adaptive traits. Evidence suggesting associations with creativity, novelty seeking, leadership, or resilience most often refers to subclinical bipolar spectrum traits or temperamental characteristics observed in unaffected relatives of individuals with bipolar disorder. In contrast, the fully expressed clinical disorder is typically associated with significant functional impairment, mood instability, and increased morbidity. Therefore, the possible adaptive value proposed in the evolutionary framework should be understood primarily in relation to temperamental or subclinical traits that may exist along a continuum of vulnerability, rather than to the severe clinical manifestations of bipolar disorder. Importantly, this perspective does not imply that acute manic or depressive episodes are adaptive or beneficial, as these episodes are frequently associated with substantial clinical impairment and risk. It emerges that divergent thinking, often present in these clinical pictures, allows for a good level of cognitive ability with activation of the associative network and creative ideation, conferring an advantageous trait in areas such as writing (19). Further supporting the hypothesis of adaptive advantages, studies have found that features of the bipolar spectrum, particularly hyperthymic traits, are more frequently observed among students in artistic disciplines and individuals engaged in highly creative fields (45,46). Similarly, elevated levels of risk-taking behavior, often associated with hypomanic temperamental features, have been reported among elite athletes participating in extreme and high-risk sports disciplines (45)(46)(47). These findings suggest that creativity, novelty seeking, and resilience under stress may have provided significant evolutionary advantages in exploration, innovation, and social leadership (47). Mixed presentations in bipolar disorder illustrate how the boundary between temperamental traits and clinically impairing mood dysregulation can become blurred, highlighting the dimensional nature of bipolar phenomenology and the importance of careful diagnostic and therapeutic management (48). A hyperthymic, social, and energetic temperament may bring advantages in leadership and exploration. At the same time, it is important to recognize that the expression of bipolar spectrum traits is highly heterogeneous and strongly influenced by contextual moderators. Cultural environments, occupational demands, and social structures may shape whether characteristics such as elevated energy, novelty seeking, creativity, or risk-taking are expressed in adaptive or maladaptive ways. In certain contexts, such as creative professions, leadership roles, or exploratory environments, these traits may facilitate innovation, productivity, and resilience under stress. In other contexts, however, the same characteristics may contribute to functional difficulties, interpersonal conflict, or clinical destabilization (23,49). This context-dependent variability highlights the importance of considering environmental and sociocultural factors when interpreting the potential adaptive dimensions of bipolar spectrum traits (49). In light of these considerations, it is hypothesized that subclinical forms of BD may have some adaptive advantage (50). Otherwise, it might be expected that a disorder associated with substantial functional impairment and reduced life expectancy would gradually decrease in frequency over evolutionary time, unless counterbalanced by mechanisms such as polygenic architecture, pleiotropic effects, or potential adaptive advantages linked to related temperamental traits (23,51). Recognizing these traits as potential adaptive advantages rather than solely pathological expressions may help foster more nuanced societal views, potentially mitigating the stigma that often surrounds individuals diagnosed with BD. Figure 1. Evolutionary-Adaptive Hypothesis of Bipolar Disorder: Genetic, Environmental, and Functional Aspects. This schematic representation illustrates a heuristic conceptual model integrating genetic vulnerability, environmental influences, and temperamental traits associated with the bipolar spectrum. It is intended as an interpretative framework to facilitate discussion of potential evolutionary mechanisms and should not be considered an empirically validated causal model. Based on ethological and genetic evaluations of primates, hyperactive individuals may develop better stress adaptation (57).The literature proposes that 5-10% of young rhesus monkeys observed in the wild growing up in herds manifest hyperactivity and aggression under even moderate stress situations, showing altered central serotonin metabolism (58).The rapidity of these social changes brought about by globalization has thus entailed changes in adaptation and communication (59). Exploratory and aggressive traits may be adaptive in marked stress due to gene-environment interactions. In contrast, in low-stress situations, the social network may perceive the aggressive trait as pathological by not turning out to be adaptive. This view thus has a more sustainable basis than hypotheses in which BD is viewed solely as an epiphenomenon of an altered genetic profile (60).It seems reasonable to hypothesize that hyperactivity and increased energy level, potentially hypomanic elements, may be an advantage in social functioning (61,62). It also emerges that social skills, exploratory and risk-taking behavior, problemsolving ability, and creativity are often improved among family members of people with BD, that is, in relatives without a BD diagnosis and even well-adjusted relatives (63,64). Furthermore, while the mild to moderate expression of shared vulnerability traits may have some advantage concerning greater creativity, the more obvious forms of pathology characterized by poor judgment and greater impulsivity appear to detract from good social performance (65,66).Current clinical therapeutic practice in bipolar disorder has traditionally focused primarily on symptom stabilization and relapse prevention, sometimes leaving less room for approaches aimed at integrating patients' strengths, functional capacities, and individual life goals. It should likewise be noted that multiple aspects of creative occupations can have an exacerbating or stimulating effect on symptomatology, in particular, increased stress, use of psychotropic substances and alcohol, and dysregulated schedules (63). Nonetheless, the positive aspects of stimulated creativity may include a higher level of contentment and improved social functioning; thus, it is evident that the activation of creative functionality and its expression at the occupational level could be a challenge for the clinical management practice of the individual with BD (67,68).The literature of recent decades provides consistent evidence about a familial link between manifestations of BD and creativity. Still, more knowledge must be gained to support the hypothesis about a net link between BD and the creative process. However, at the same time, it has been ascertained that a moderately elevated mood can increase the fluidity of thinking, particularly in its divergent form. In contrast, a highly elevated mood can antagonize the creative realization process (69-72). In defining these aspects, therefore, it is evident that shared vulnerabilities reflecting both a predisposition to creativity and a genetic risk for the disease may be considered candidates for adaptive traits according to a balancing selection suitable to allow the persistence of BD in the population despite the inherent disadvantages arising from the pathological picture. This interpretation is consistent with broader evolutionary models suggesting that behavioral diversity within human populations may be maintained through mechanisms of balancing selection. According to these models, temperamental traits related to increased energy, novelty seeking, and risk-taking may confer advantages in certain environmental or social contexts, even if their extreme expressions increase vulnerability to psychiatric conditions. From this perspective, bipolar spectrum traits may represent the upper tail of normally distributed adaptive behavioral strategies that have historically contributed to exploration, innovation, and leadership within human groups (73,74). Considering these aspects from a genetic perspective may further elucidate the biological mechanisms underlying disease risk. It may also contribute to identifying novel targets for both psychosocial and pharmacological interventions (75). The debate can also be observed in the literature regarding the possible identification of a specific dysregulation of mood, energy, and social rhythms syndrome, characterized by a high degree of personal distress with reduced social functioning, which could be the result of a nonspecific response to environmental hyper-stress under conditions of increased individual, genetic, social, and clinical vulnerability (19,76). Furthermore, growing evidence suggests that disturbances in biological rhythms, including sleep-wake cycles and activity patterns, are a core feature of bipolar disorder. Studies have consistently shown a higher prevalence of the evening chronotype among individuals with bipolar spectrum disorders, characterized by a preference for later sleep and activity times. In a society predominantly oriented toward morning activities and schedules, this misalignment may exacerbate stress, contribute to social and occupational dysfunction, and increase vulnerability to mood episodes (77). Such positive reframing of creative abilities may serve as a key component in counteracting stigma and promoting a strengths-based model of care for individuals at risk or diagnosed with BD.It is important to emphasize that the evolutionary perspective discussed in this article should be interpreted primarily as a heuristic framework rather than a definitive explanatory model. While several empirical findings support the association between bipolar spectrum traits and domains such as creativity, novelty seeking, and adaptive stress responses, the hypothesis that these traits may have been maintained through evolutionary processes remains partly speculative. Consequently, the evidence presented here should be understood as an attempt to integrate established findings with emerging theoretical interpretations, with the aim of stimulating further interdisciplinary research on the biological and psychosocial mechanisms underlying bipolar spectrum conditions. The current approach to BD identifies adaptive potential as a focus of psychosocial treatment and drug therapy (78). This interpretation of clinical and social management could also decrease discrimination and stigma toward people suffering from BD (79)(80)(81)(82).Beyond its conceptual and stigma-reducing implications, the evolutionary-adaptive framework may also contribute to clinical reasoning in several ways. Recognizing that certain temperamental features associated with the bipolar spectrum, such as elevated energy, creativity, novelty seeking, and social drive, may represent amplified expressions of traits that can be advantageous in specific contexts may encourage clinicians to adopt a more nuanced and strengths-based perspective. In psychosocial practice, this approach may support interventions aimed at helping individuals channel these traits into structured and adaptive activities, while simultaneously promoting strategies to regulate sleep-wake cycles, stress exposure, and emotional reactivity. Such a perspective does not replace established evidence-based pharmacological and psychosocial treatments but may complement them by fostering more personalized approaches that integrate symptom management with the promotion of functional strengths. From a clinical perspective, this evolutionary interpretation should not be considered a direct guide for treatment decisions; rather, it may contribute to a broader conceptual framework that encourages clinicians to recognize both the vulnerabilities and the potential functional strengths associated with bipolar spectrum temperamental traits.In addition, promoting an understanding of bipolar disorder as a condition potentially rooted in adaptive traits offers valuable avenues for reducing stigma. Nevertheless, it is important to acknowledge the potential risk of misinterpretation when discussing adaptive or strengths-related aspects of bipolar spectrum traits. Such perspectives should not be interpreted as romanticizing bipolar disorder or minimizing the significant disability, relapse risk, and clinical burden associated with the condition. Rather, a strengths-based reframing should be understood as a complementary perspective that coexists with a realistic clinical recognition of the challenges and vulnerabilities experienced by many individuals with bipolar disorder. Such a reframing could lead to psychosocial strategies that not only aim at symptom control but also at enhancing patients' strengths, ultimately contributing to better clinical outcomes and improved societal acceptance. At the same time, it is essential to acknowledge the limitations of the evolutionary perspective proposed in this article. Bipolar disorder remains a severe psychiatric condition associated with significant functional impairment, high relapse rates, and increased risk of suicide and premature mortality. Therefore, the hypothesis that certain bipolar spectrum traits may have historically conferred adaptive advantages should not be interpreted as minimizing the profound suffering and clinical burden experienced by many individuals with the disorder. Rather, this framework should be viewed as a complementary perspective that may help contextualize certain temperamental features within broader evolutionary and psychosocial processes. In clinical practice, such an interpretation may contribute to a more balanced and stigma-reducing approach, while maintaining a clear focus on early diagnosis, evidence-based treatment, and the prevention of adverse outcomes. In conclusion, although BD is still currently a relevant issue in health care, potentially causing marked disability, the possibility emerges from the literature that it represents an adaptive advantage in situations of marked stress, suggesting how individualized treatment strategies aimed at maintaining such positive aspects while limiting disadvantageous manifestations could lead to improved outcomes. In summary, considering bipolar disorder through an evolutionary-informed perspective may offer a complementary framework for integrating genetic vulnerability, temperamental traits, and environmental influences. Such an approach may have several implications: clinically, it may encourage more nuanced and strengths-informed perspectives on bipolar spectrum traits; societally, it may contribute to reducing stigma by challenging exclusively deficit-based narratives; and scientifically, it may stimulate further interdisciplinary research on the evolutionary and biological mechanisms underlying mood dysregulation. At the same time, this perspective must be interpreted with caution and should not be understood as minimizing the significant clinical burden associated with bipolar disorder. Rather, it should be viewed as a heuristic