RESUMO
Depression is a prevalent and incapacitating condition with a significant impact on global morbidity and mortality. Although the immune system's role in its pathogenesis is increasingly recognized, there is a lack of comprehensive understanding regarding the involvement of innate and adaptive immune cells. To address this gap, we conducted a multicenter case-control study involving 121 participants matched for sex and age. These participants had either an active (or current) major depressive episode (MDE) (39 cases) or a remitted MDE (40 cases), including individuals with major depressive disorder or bipolar disorder. We compared these 79 patients to 42 healthy controls (HC), analyzing their immunological profiles. In blood samples, we determined the complete cell count and the monocyte subtypes and lymphocyte T-cell populations using flow cytometry. Additionally, we measured a panel of cytokines, chemokines, and neurotrophic factors in the plasma. Compared with HC, people endorsing a current MDE showed monocytosis (p = 0.001), increased high-sensitivity C-reactive protein (p = 0.002), and erythrocyte sedimentation rate (p = 0.003), and an altered proportion of specific monocyte subsets. CD4 lymphocytes presented increased median percentages of activation markers CD69+ (p = 0.007) and exhaustion markers PD1+ (p = 0.013) and LAG3+ (p = 0.014), as well as a higher frequency of CD4+CD25+FOXP3+ regulatory T cells (p = 0.003). Additionally, patients showed increased plasma levels of sTREM2 (p = 0.0089). These changes are more likely state markers, indicating the presence of an ongoing inflammatory response during an active MDE. The Random Forest model achieved remarkable classification accuracies of 83.8% for MDE vs. HC and 70% for differentiating active and remitted MDE. Interestingly, the cluster analysis identified three distinct immunological profiles among MDE patients. Cluster 1 has the highest number of leukocytes, mainly given by the increment in lymphocyte count and the lowest proinflammatory cytokine levels. Cluster 3 displayed the most robust inflammatory pattern, with high levels of TNFα, CX3CL1, IL-12p70, IL-17A, IL-23, and IL-33, associated with the highest level of IL-10, as well as ß-NGF and the lowest level for BDNF. This profile is also associated with the highest absolute number and percentage of circulating monocytes and the lowest absolute number and percentage of circulating lymphocytes, denoting an active inflammatory process. Cluster 2 has some cardinal signs of more acute inflammation, such as elevated levels of CCL2 and increased levels of proinflammatory cytokines such as IL-1ß, IFNγ, and CXCL8. Similarly, the absolute number of monocytes is closer to a HC value, as well as the percentage of lymphocytes, suggesting a possible initiation of the inflammatory process. The study provides new insights into the immune system's role in MDE, paving the ground for replication prospective studies targeting the development of diagnostic and prognostic tools and new therapeutic targets.
Assuntos
Citocinas , Transtorno Depressivo Maior , Imunofenotipagem , Monócitos , Humanos , Feminino , Masculino , Estudos de Casos e Controles , Transtorno Depressivo Maior/imunologia , Transtorno Depressivo Maior/sangue , Adulto , Pessoa de Meia-Idade , Citocinas/sangue , Citocinas/imunologia , Monócitos/imunologia , Transtorno Bipolar/imunologia , Transtorno Bipolar/sangue , Inflamação/imunologia , Inflamação/sangue , Antígenos CD/sangue , Antígenos CD/imunologia , Citometria de FluxoRESUMO
Background: Suicidal ideation and attempt (SI/SA) have been associated with dysregulation of the immune response and inflammation. However, few studies have explored how innate and acquired cellular immunity impact on the peripheral immune response. Our study addresses this gap by examining the composition of peripheral immune cells and humoral markers among individuals with current SI/SA, individuals with a history of SI/SA, and healthy controls (HC). Additionally, we aim to explore whether depressive symptoms settle the relationship between inflammation and SI/SA. Methods: This is a multicenter case-control study that included 105 participants. Clinical and demographic characterists together with hemogram parameters, soluble pro and anti-inflamatory factors, and specific innate and adaptive immune cell populations were compared among patients with current SI/SA (n = 21), a history of lifetime SI/SA (n = 42), and HC (n = 42). Results: Patients with both current and lifetime SI/SA had a significant increase in the absolute count of monocytes and in the monocyte/lymphocyte ratio (MLR). Additionally, patients with current and lifetime SI/SA showed a significant increase in high-sensitivity C- reactive protein (hs-CRP), and patients with lifetime SI/SA also showed higher levels of Erythrocyte Sedimentation Rate (ESR). The cellular inflammatory status of patients with SI/SA was characterized by altered proportions of monocytes with higher levels of nonclassical and intermediate monocytes. No differences were observed in the number of lymphocytes and the proportion of CD4 and CD8 between patients and HC, but we found differences in markers of exhaustion of CD4 lymphocytes, with increased levels of Programmed cell death protein 1 (PD1) in Current SI/SA and Lymphocyte activation gene 3 (LAG3) in Current SI/SA and Lifetime SI/SA compared to HC. The plasmainflammatory status was marked by higher levels of soluble Triggering receptor expressed on myeloid cells 2 (sTREM2) in patients with lifetime SI/SA compared to HC. Finally, the multinomial analysis indicates that inflammation and depressive symptoms are independently associated with SI/SA. Conclusion: This study highlights the association of immunological alterations with SI/SA. Furthremore, SI/SA is independently influenced by depressive symptoms and inflammation. This may have important therapeutic implications, as in these patients, it may be necessary to treat the inflammatory process beyond treating the depressive symptoms.
RESUMO
BACKGROUND: There are scarce and discrepant data about the prevalence and correlates of co-occurring eating disorders (EDs) among people with a primary diagnosis of bipolar disorder (BD), and vice-versa, compelling a systematic review and meta-analysis on the matter. METHODS: MEDLINE/PsycINFO databases were systematically searched for original studies documenting BDâED comorbidity across the lifespan, from inception up until April 20th, 2020. Random-effects meta-analysis and meta-regression analyses were conducted, accounting for multiple moderators. RESULTS: Thirty-six studies involved 15,084 primary BD patients. Eleven studies encompassed 15,146 people with primary EDs. Binge eating disorder (BED) occurred in 12.5% (95%C.I.=9.4-16.6%, I2=93.48%) of BDs, while 9.1% (95%C.I.=3.3-22.6%) of BEDs endorsed BD. Bulimia Nervosa (BN) occurred in 7.4% (95%C.I.=6-10%) of people with BD, whereas 6.7% (95%C.I.=12-29.2%) of subjects with BN had a diagnosis of BD. Anorexia Nervosa (AN) occurred in 3.8% (95%C.I.=2-6%) of people with BDs; 2% (95%C.I.=1-2%) of BD patients had a diagnosis of AN. Overall, BD patients with EDs had higher odds of being female vs. non-ED controls. Several moderators yielded statistically significant differences both within- and between different types of BDs and EDs. LIMITATIONS: Scant longitudinal studies, especially across different EDs and pediatric samples. High heterogeneity despite subgroup comparisons. Limited discrimination of the quality of the evidence. CONCLUSIONS: The rates of BDâED comorbidity vary across different diagnostic groups, more than they do according to the "direction" of BDâED. Further primary studies should focus on the risks, chronology, clinical impact, and management of the onset of intertwined BDâED across different ages, promoting a continuum approach.