Genetic factor common to schizophrenia and HIV infection is associated with risky sexual behavior: antagonistic vs. synergistic pleiotropic SNPs enriched for distinctly different biological functions

The prevalence of mental health disorders in people with HIV and the effects on the HIV care continuum

OBJECTIVE

To describe the prevalence of diagnosed depression, anxiety, bipolar disorder, and schizophrenia in people with HIV (PWH) and the differences in HIV care continuum outcomes in those with and without mental health disorders (MHDs).

DESIGN

Observational study of participants in the North American AIDS Cohort Collaboration on Research and Design.

METHODS

PWH (≥18 years) contributed data on prevalent schizophrenia, anxiety, depressive, and bipolar disorders from 2008 to 2018 based on International Classification of Diseases code mapping. Mental health (MH) multimorbidity was defined as having two or more MHD. Log binomial models with generalized estimating equations estimated adjusted prevalence ratios (aPR) and 95% confidence intervals for retention in care (≥1 visit/year) and viral suppression (HIV RNA ≤200 copies/ml) by presence vs. absence of each MHD between 2016 and 2018.

RESULTS

Among 122 896 PWH, 67 643 (55.1%) were diagnosed with one or more MHD: 39% with depressive disorders, 28% with anxiety disorders, 10% with bipolar disorder, and 5% with schizophrenia. The prevalence of depressive and anxiety disorders increased between 2008 and 2018, whereas bipolar disorder and schizophrenia remained stable. MH multimorbidity affected 24% of PWH. From 2016 to 2018 (N = 64 684), retention in care was marginally lower among PWH with depression or anxiety, however those with MH multimorbidity were more likely to be retained in care. PWH with bipolar disorder had marginally lower prevalence of viral suppression (aPR = 0.98 [0.98-0.99]) as did PWH with MH multimorbidity (aPR = 0.99 [0.99-1.00]) compared with PWH without MHD.

CONCLUSION

The prevalence of MHD among PWH was high, including MH multimorbidity. Although retention and viral suppression were similar to people without MHD, viral suppression was lower in those with bipolar disorder and MH multimorbidity.

PolarMorphism enables discovery of shared genetic variants across multiple traits from GWAS summary statistics

MOTIVATION

Pleiotropic SNPs are associated with multiple traits. Such SNPs can help pinpoint biological processes with an effect on multiple traits or point to a shared etiology between traits. We present PolarMorphism, a new method for the identification of pleiotropic SNPs from genome-wide association studies (GWAS) summary statistics. PolarMorphism can be readily applied to more than two traits or whole trait domains. PolarMorphism makes use of the fact that trait-specific SNP effect sizes can be seen as Cartesian coordinates and can thus be converted to polar coordinates r (distance from the origin) and theta (angle with the Cartesian x-axis, in the case of two traits). r describes the overall effect of a SNP, while theta describes the extent to which a SNP is shared. r and theta are used to determine the significance of SNP sharedness, resulting in a P-value per SNP that can be used for further analysis.

RESULTS

We apply PolarMorphism to a large collection of publicly available GWAS summary statistics enabling the construction of a pleiotropy network that shows the extent to which traits share SNPs. We show how PolarMorphism can be used to gain insight into relationships between traits and trait domains and contrast it with genetic correlation. Furthermore, pathway analysis of the newly discovered pleiotropic SNPs demonstrates that analysis of more than two traits simultaneously yields more biologically relevant results than the combined results of pairwise analysis of the same traits. Finally, we show that PolarMorphism is more efficient and more powerful than previously published methods.

AVAILABILITY AND IMPLEMENTATION

code: https://github.com/UMCUGenetics/PolarMorphism, results: 10.5281/zenodo.5844193.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

[Social, demographic and clinical characteristics of female patients with schizophrenia and HIV]

OBJECTIVE

To evaluate social, demographic and clinical characteristics of women with schizophrenia and HIV.

MATERIAL AND METHODS

Medical histories of patients who were in inpatient treatment during 2017 were retrospectively studied. A total of 174 medical histories were analyzed, but the final analysis included 40 HIV-infected patients (main groups) and 48 patients without HIV infection (comparison group). These groups included patients with a diagnosis of schizophrenia or acute polymorphic psychotic disorder. All patients with HIV infection were examined by a specialist and an immunological analysis was performed. Correlation analysis was performed between quantitative clinical indicators (duration of illness, number of hospitalizations, the number and duration of remissions, etc.) and immunological parameters.

RESULTS AND CONCLUSION

Patients with schizophrenia and HIV infection are more often hospitalized and stay in the hospital longer than patients with schizophrenia without HIV infection, which may in part be determined by the social problems of this cohort of patients. There is a relationship between individual indicators of the immune status of the patients, the duration and some features of the course of mental illness. Regular treatment of HIV infection correlates with a lower frequency of hospitalizations in a psychiatric hospital due to an exacerbation of the mental state.

The Risk of Sexually Transmitted Infections Following First-Episode Schizophrenia Among Adolescents and Young Adults: A Cohort Study of 220 545 Subjects

Young people are disproportionately affected by sexually transmitted infections (STIs). The risk of STIs in young people following first-episode schizophrenia is unknown. This study using Taiwan's National Health Insurance Research Database enrolled 44 109 adolescents and young adults with first-episode schizophrenia and 176 436 age- and sex-matched controls without schizophrenia from 2001 through 2009 and followed to the end of 2011. New-onset STIs were identified. Survival analysis was performed. Cox regression analysis was used to examine the effects of comorbid substance use disorder (SUD), schizophrenia medications, and schizophrenia severity. The E value for causality of evidence was calculated. We found that young people had a higher risk of STIs following first-episode schizophrenia compared with controls without schizophrenia (hazard ratio [HR] = 2.35, 95% CI = 2.08-2.64); these STIs included human immunodeficiency virus (HIV) (3.70, 2.60-5.28) and syphilis (5.35, 3.96-7.23). They also showed a disproportionate distribution of STIs, with an increased proportion of syphilis (20.4% vs 8.2%) and HIV (9.1% vs 6.0%). When presenting with SUD, the risks of HIV (11.00, 7.02-17.25) and syphilis (9.11, 6.16-13.47) were further increased. The severe schizophrenia group had an extremely high risk of syphilis (41.26, 27.69-61.47) and HIV (7.50, 3.85-14.62). Schizophrenia medications may provide beneficial effects against contracting STIs (0.77, 0.68-0.89). We concluded that following first-episode schizophrenia, young patients are at higher risk of STIs, particularly HIV and syphilis. The risk further increased when subjects presented with SUD or severe schizophrenia. Importantly, antipsychotic treatment may lower the risk of STIs.

A large-scale genomic investigation of susceptibility to infection and its association with mental disorders in the Danish population

Infections and mental disorders are two of the major global disease burdens. While correlations between mental disorders and infections have been reported, the possible genetic links between them have not been assessed in large-scale studies. Moreover, the genetic basis of susceptibility to infection is largely unknown, as large-scale genome-wide association studies of susceptibility to infection have been lacking. We utilized a large Danish population-based sample (N = 65,534) linked to nationwide population-based registers to investigate the genetic architecture of susceptibility to infection (heritability estimation, polygenic risk analysis, and a genome-wide association study (GWAS)) and examined its association with mental disorders (comorbidity analysis and genetic correlation). We found strong links between having at least one psychiatric diagnosis and the occurrence of infection (P = 2.16 × 10-208, OR = 1.72). The SNP heritability of susceptibility to infection ranged from ~2 to ~7% in samples of differing psychiatric diagnosis statuses (suggesting the environment as a major contributor to susceptibility), and polygenic risk scores moderately but significantly explained infection status in an independent sample. We observed a genetic correlation of 0.496 (P = 2.17 × 10-17) between a diagnosis of infection and a psychiatric diagnosis. While our GWAS did not identify genome-wide significant associations, we found 90 suggestive (P ≤ 10-5) associations for susceptibility to infection. Our findings suggest a genetic component in susceptibility to infection and indicate that the occurrence of infections in individuals with mental illness may be in part genetically driven.

Schizophrenia risk and reproductive success: a Mendelian randomization study

Schizophrenia is a debilitating and heritable mental disorder associated with lower reproductive success. However, the prevalence of schizophrenia is stable over populations and time, resulting in an evolutionary puzzle: how is schizophrenia maintained in the population, given its apparent fitness costs? One possibility is that increased genetic liability for schizophrenia, in the absence of the disorder itself, may confer some reproductive advantage. We assessed the correlation and causal effect of genetic liability for schizophrenia with number of children, age at first birth and number of sexual partners using data from the Psychiatric Genomics Consortium and UK Biobank. Linkage disequilibrium score regression showed little evidence of genetic correlation between genetic liability for schizophrenia and number of children (r g = 0.002, p = 0.84), age at first birth (r g = -0.007, p = 0.45) or number of sexual partners (r g = 0.007, p = 0.42). Mendelian randomization indicated no robust evidence of a causal effect of genetic liability for schizophrenia on number of children (mean difference: 0.003 increase in number of children per doubling in the natural log odds ratio of schizophrenia risk, 95% confidence interval (CI): -0.003 to 0.009, p = 0.39) or age at first birth (-0.004 years lower age at first birth, 95% CI: -0.043 to 0.034, p = 0.82). We find some evidence of a positive effect of genetic liability for schizophrenia on number of sexual partners (0.165 increase in the number of sexual partners, 95% CI: 0.117-0.212, p = 5.30×10-10). These results suggest that increased genetic liability for schizophrenia does not confer a fitness advantage but does increase mating success.

Schizophrenia is associated with an increased risk of sexually transmitted infections: A nationwide population-based cohort study in Taiwan

OBJECTIVES

In Taiwan, there has been a growing emphasis on physical health screening, health education and improving access to treatment in patients with schizophrenia (SCZ). However, sexual health needs, including screening and prevention of sexually transmitted infections (STI), are neglected in this population. The study aimed to investigate the association between SCZ and the subsequent incident STI and to examine potential risk factors.

METHODS

Using the National Health Insurance Research Database of Taiwan, 58,948 SCZ patients and 235,784 controls matched by gender and age were enrolled between 2000 and 2010 and followed until the end of 2011. Participants who developed any STI (HIV, syphilis, genital warts, gonorrhea, chlamydial infection, and trichomoniasis) during the follow-up period were identified. Cox regression analysis was performed to examine the risk of STI between SCZ patients and controls.

RESULTS

SCZ patients were predisposed to developing STI (hazard ratio (HR): 1.11, 95% confidence interval (95% CI): 1.01-1.21) that could be caused by syphilis (HR: 2.58, 95% CI: 2.14-3.10) or possibly HIV (Crude HR: 1.39, 95% CI: 1.04-1.86; adjusted HR: 1.11, 95% CI: 0.81-1.52). Additionally, this study found that female, young adults, low-income, living in less urbanized areas, and comorbid substance abuse were potential risk factors for developing STI.

CONCLUSION

This study shows that SCZ is associated with an increased risk of developing STI, which has direct implications for the development of targeted prevention interventions or regular sexual health screening in mental health clinics to reduce the disproportionate burden of HIV and other STI in SCZ patients.

Polygenic Risk Scores in Clinical Psychology: Bridging Genomic Risk to Individual Differences

Genomewide association studies (GWASs) across psychiatric phenotypes have shown that common genetic variants generally confer risk with small effect sizes (odds ratio < 1.1) that additively contribute to polygenic risk. Summary statistics derived from large discovery GWASs can be used to generate polygenic risk scores (PRS) in independent, target data sets to examine correlates of polygenic disorder liability (e.g., does genetic liability to schizophrenia predict cognition?). The intuitive appeal and generalizability of PRS have led to their widespread use and new insights into mechanisms of polygenic liability. However, when currently applied across traits they account for small amounts of variance (<3%), are relatively uninformative for clinical treatment, and, in isolation, provide no insight into molecular mechanisms. Larger GWASs are needed to increase the precision of PRS, and novel approaches integrating various data sources (e.g., multitrait analysis of GWASs) may improve the utility of current PRS.

Genetically determined schizophrenia is not associated with impaired glucose homeostasis

Here, we used data from large genome-wide association studies to test the presence of causal relationships, conducting a Mendelian randomization analysis; and shared molecular mechanisms, calculating the genetic correlation, among schizophrenia, type 2 diabetes (T2D), and impaired glucose homeostasis. Although our Mendelian randomization analysis was well-powered, no causal relationship was observed between schizophrenia and T2D, or traits related to glucose impaired homeostasis. Similarly, we did not observe any global genetic overlap among these traits. These findings indicate that there is no causal relationships or shared mechanisms between schizophrenia and impaired glucose homeostasis.

Local adaptation in European populations affected the genetics of psychiatric disorders and behavioral traits

Background

Recent studies have used genome-wide data to investigate evolutionary mechanisms related to behavioral phenotypes, identifying widespread signals of positive selection. Here, we conducted a genome-wide investigation to study whether the molecular mechanisms involved in these traits were affected by local adaptation.

Methods

We performed a polygenic risk score analysis in a sample of 2455 individuals from 23 European populations with respect to variables related to geo-climate diversity, pathogen diversity, and language phonological complexity. The analysis was adjusted for the genetic diversity of European populations to ensure that the differences detected would reflect differences in environmental exposures.

Results

The top finding was related to the association between winter minimum temperature and schizophrenia. Additional significant geo-climate results were also observed with respect to bipolar disorder (sunny daylight), depressive symptoms (precipitation rate), major depressive disorder (precipitation rate), and subjective well-being (relative humidity). Beyond geo-climate variables, we also observed findings related to pathogen diversity and language phonological complexity: openness to experience was associated with protozoan diversity; conscientiousness and extraversion were associated with language consonants.

Conclusions

We report that common variation associated with psychiatric disorders and behavioral traits was affected by processes related to local adaptation in European populations.

Electronic supplementary material

The online version of this article (10.1186/s13073-018-0532-7) contains supplementary material, which is available to authorized users.

Ancestry-specific and sex-specific risk alleles identified in a genome-wide gene-by-alcohol dependence interaction study of risky sexual behaviors

We previously mapped loci for the genome-wide association studies (GWAS) and genome-wide gene-by-alcohol dependence interaction (GW-GxAD) analyses of risky sexual behaviors (RSB). This study extends those findings by analyzing the ancestry- and sex-specific AD-stratified effects on RSB. We examined the concordance of findings for the AD-stratified GWAS and the GW-GxAD analysis of RSB, with concordance defined as genome-wide significance in one analysis and at least nominal significance in the second analysis. A total of 2,173 African-American (AA) and 1,751 European-American (EA) subjects were investigated. Information regarding RSB (lifetime experiences of unprotected sex and multiple sexual partners) and DSM-IV diagnosis of lifetime AD were derived from the Semi-Structured Assessment for Drug Dependence and Alcoholism (SSADDA). In our ancestry- and sex-specific analyses, we identified four independent genome-wide significant (GWS) loci (p < 5*10-8 ) and one suggestive locus (p < 6*10-8 ). In men, we observed a GWS signal in FAM162A (rs2002594, p = 4.96*10-8 ). In women, there was a suggestive locus in PLGRKT (rs3824435, p = 5.52*10-8 ). In AAs, there was a GWS signal in GRK5 (rs1316543, p = 1.25*10-9 ). In AA men, we observed an intergenic GWS signal (rs12898370, p = 4.49*10-8 ) near LINGO1. In EA men, there was a GWS signal in CCSER1 (rs62313897; p = 7.93*10-10 ). The loci identified in this GWAS implicate molecular mechanisms related to psychiatric illness and personality features, suggesting that the interplay between AD and RSB is mediated by alleles associated with behavioral traits.

S100A10 identified in a genome-wide gene × cannabis dependence interaction analysis of risky sexual behaviours

BACKGROUND

We conducted a genome-wide gene × environment interaction analysis to identify genetic variants that interact with cannabis dependence (CaD) in influencing risky sexual behaviours (RSB).

METHODS

Our sample included cannabis-exposed and sexually experienced African-American and European-American participants. A DSM-IV CaD diagnosis and RSB were evaluated using the Semi-Structured Assessment for Drug Dependence and Alcoholism. We analyzed RSBs as a score that takes into account experiences of unprotected sex and multiple sexual partners.

RESULTS

A total of 3350 people participated in our study; 43% had a CaD diagnosis, 56% were African-American and 33% were women. We identified a genome-wide significant locus in African-American participants (S100A10 rs72993629, p = 2.73 × 10^-8) and a potential transpopulation signal in women (CLTC rs12944716, p = 5.27 × 10^-8). A resting-state fMRI follow-up analysis of S100A10 rs72993629 conducted in an independent cohort showed 2 significant associations: reduced power of the left paracentral lobule in amplitude of low frequency fluctuations (ALFF) analysis (p = 7.8 × 10^-3) and reduced power of the right pallidum in fractional ALFF analysis (p = 4.6 × 10^-3). The activity of these brain regions is known to be involved in sexual functions and behaviours. The S100A10 result functionally recapitulated our S100B finding observed in our previous genome-wide association study of CaD. The probability of identifying 2 S100 genes in 2 independent genome-wide investigations by chance is approximately 1 in 1.1 million.

LIMITATIONS

We were not able to identify any African-American cohort with appropriate sample size, and phenotypic assessment is available to replicate our findings.

CONCLUSION

The S100A10 and S100B genes, which are located on different chromosomes, encode specialized calcium-binding proteins. These data support a role for calcium homeostasis in individuals with CaD and its induced behaviours.