A meta-analysis of gene expression signatures of blood pressure and hypertension.

Genome-wide association studies (GWAS) have uncovered numerous genetic variants (SNPs) that are associated with blood pressure (BP). Genetic variants may lead to BP changes by acting on intermediate molecular phenotypes such as coded protein sequence or gene expression, which in turn affect BP variability. Therefore, characterizing genes whose expression is associated with BP may reveal cellular processes involved in BP regulation and uncover how transcripts mediate genetic and environmental effects on BP variability. A meta-analysis of results from six studies of global gene expression profiles of BP and hypertension in whole blood was performed in 7017 individuals who were not receiving antihypertensive drug treatment. We identified 34 genes that were differentially expressed in relation to BP (Bonferroni-corrected p<0.05). Among these genes, FOS and PTGS2 have been previously reported to be involved in BP-related processes; the others are novel. The top BP signature genes in aggregate explain 5%-9% of inter-individual variance in BP. Of note, rs3184504 in SH2B3, which was also reported in GWAS to be associated with BP, was found to be a trans regulator of the expression of 6 of the transcripts we found to be associated with BP (FOS, MYADM, PP1R15A, TAGAP, S100A10, and FGBP2). Gene set enrichment analysis suggested that the BP-related global gene expression changes include genes involved in inflammatory response and apoptosis pathways. Our study provides new insights into molecular mechanisms underlying BP regulation, and suggests novel transcriptomic markers for the treatment and prevention of hypertension.

Sex- and age-interacting eQTLs in human complex diseases.

Many complex human diseases exhibit sex or age differences in gene expression. However, the presence and the extent of genotype-specific variations in gene regulation are largely unknown. Here, we report results of a comprehensive analysis of expression regulation of genetic variation related to 11,672 complex disease-associated SNPs as a function of sex and age in whole-blood-derived RNA from 5254 individuals. At false discovery rate <0.05, we identified 14 sex- and 10 age-interacting expression quantitative trait loci (eQTLs). We show that these eQTLs are also associated with many sex- or age-associated traits. These findings provide important context regarding the regulation of phenotypes by genotype-environment interaction.

Integrative network analysis reveals molecular mechanisms of blood pressure regulation.

Genome-wide association studies (GWAS) have identified numerous loci associated with blood pressure (BP). The molecular mechanisms underlying BP regulation, however, remain unclear. We investigated BP-associated molecular mechanisms by integrating BP GWAS with whole blood mRNA expression profiles in 3,679 individuals, using network approaches. BP transcriptomic signatures at the single-gene and the coexpression network module levels were identified. Four coexpression modules were identified as potentially causal based on genetic inference because expression-related SNPs for their corresponding genes demonstrated enrichment for BP GWAS signals. Genes from the four modules were further projected onto predefined molecular interaction networks, revealing key drivers. Gene subnetworks entailing molecular interactions between key drivers and BP-related genes were uncovered. As proof-of-concept, we validated SH2B3, one of the top key drivers, using Sh2b3(-/-) mice. We found that a significant number of genes predicted to be regulated by SH2B3 in gene networks are perturbed in Sh2b3(-/-) mice, which demonstrate an exaggerated pressor response to angiotensin II infusion. Our findings may help to identify novel targets for the prevention or treatment of hypertension.

Whole blood gene expression and interleukin-6 levels.

BACKGROUND: Circulating interleukin-6 levels increase with advancing age and are a risk factor for various diseases and mortality. The characterization of gene expression profiles associated with interleukin-6 levels might suggest important molecular events underlying its regulation. METHODS AND RESULTS: We studied the association of transcriptional profiles with interleukin-6 levels in 2422 participants from the Framingham Heart Study Offspring Cohort using Affymetrix Human Exon 1.0 ST Array. We identified 4139 genes that were significantly associated with interleukin-6 levels (FDR<0.05) after adjusting for age, sex and blood cell components. We then replicated 807 genes in the InCHIANTI study with 694 participants. Many of the top genes are involved in inflammation-related pathways or erythrocyte function, including JAK/Stat signaling pathway and interleukin-10 signaling pathway. CONCLUSION: We identified and replicated 807 genes that were associated with circulating interleukin-6 levels. Future characterization of interleukin-6 regulation networks may facilitate the identification of additional potential targets for treating inflammation-related diseases.

Gene expression signatures of coronary heart disease.

OBJECTIVE: To identify transcriptomic biomarkers of coronary heart disease (CHD) in 188 cases with CHD and 188 age- and sex-matched controls who were participants in the Framingham Heart Study. APPROACH AND RESULTS: A total of 35 genes were differentially expressed in cases with CHD versus controls at false discovery rate<0.5, including GZMB, TMEM56, and GUK1. Cluster analysis revealed 3 gene clusters associated with CHD, 2 linked to increased erythrocyte production and a third to reduced natural killer and T cell activity in cases with CHD. Exon-level results corroborated and extended the gene-level results. Alternative splicing analysis suggested that GUK1 and 38 other genes were differentially spliced in cases with CHD versus controls. Gene Ontology analysis linked ubiquitination and T-cell-related pathways with CHD. CONCLUSIONS: Two bioinformatically defined groups of genes show consistent associations with CHD. Our findings are consistent with the hypotheses that hematopoesis is upregulated in CHD, possibly reflecting a compensatory mechanism, and that innate immune activity is disrupted in CHD or altered by its treatment. Transcriptomic signatures may be useful in identifying pathways associated with CHD and point toward novel therapeutic targets for its treatment and prevention.

A systems biology framework identifies molecular underpinnings of coronary heart disease.

OBJECTIVE: Genetic approaches have identified numerous loci associated with coronary heart disease (CHD). The molecular mechanisms underlying CHD gene-disease associations, however, remain unclear. We hypothesized that genetic variants with both strong and subtle effects drive gene subnetworks that in turn affect CHD. APPROACH AND RESULTS: We surveyed CHD-associated molecular interactions by constructing coexpression networks using whole blood gene expression profiles from 188 CHD cases and 188 age- and sex-matched controls. Twenty-four coexpression modules were identified, including 1 case-specific and 1 control-specific differential module (DM). The DMs were enriched for genes involved in B-cell activation, immune response, and ion transport. By integrating the DMs with gene expression-associated single-nucleotide polymorphisms and with results of genome-wide association studies of CHD and its risk factors, the control-specific DM was implicated as CHD causal based on its significant enrichment for both CHD and lipid expression-associated single-nucleotide polymorphisms. This causal DM was further integrated with tissue-specific Bayesian networks and protein-protein interaction networks to identify regulatory key driver genes. Multitissue key drivers (SPIB and TNFRSF13C) and tissue-specific key drivers (eg, EBF1) were identified. CONCLUSIONS: Our network-driven integrative analysis not only identified CHD-related genes, but also defined network structure that sheds light on the molecular interactions of genes associated with CHD risk.

Effectiveness of mRNA-1273, BNT162b2, and JNJ-78436735 COVID-19 Vaccines Among US Military Personnel Before and During the Predominance of the Delta Variant.

Importance: No studies to date have evaluated the effectiveness of 3 COVID-19 vaccines in the US military population, especially during the circulation of the SARS-CoV-2 Delta (B.1.617.2) variant. Objective: To estimate the effectiveness of the mRNA-1273, BNT162b2, and JNJ-78436735 vaccines among US military personnel before and during the predominance of the Delta variant in the US. Design, Setting, and Participants: This case-control study was conducted among all unvaccinated and fully vaccinated US military personnel who had a documented SARS-CoV-2 test performed in the US between January 1 and September 24, 2021. Individuals were identified using Department of Defense (DOD) electronic medical, laboratory, and surveillance databases. The pre-Delta period was defined as January 1 to May 31, 2021, and the Delta period as June 19 to September 24, 2021. Case individuals were defined by a positive polymerase chain reaction SARS-CoV-2 test result or a positive antigen test result with symptoms. Control individuals had at least 1 negative SARS-CoV-2 test result. Exposures: COVID-19 vaccination with the mRNA-1273, BNT162b2, or JNJ-78436735 vaccine, assessed from DOD electronic vaccination records. Main Outcomes and Measures: COVID-19 vaccine effectiveness overall, by vaccine type, and by outcome stratified by the pre-Delta and Delta periods in the US. Vaccine effectiveness was estimated as 100 × (1 - odds ratio) in a logistic regression model with adjustment for potential confounders. Results: The cohort included 441 379 individuals, with 290 256 in the pre-Delta period (236 555 [81%] male; median age, 25 years [range, 17-68 years]) and 151 123 in the Delta period (120 536 [80%] male; median age, 26 years [range, 17-70 years]). Adjusted vaccine effectiveness of all vaccines was significantly higher during the pre-Delta period (89.2%; 95% CI, 88.1%-90.1%) compared with the Delta period (70.2%; 95% CI, 69.3%-71.1%) for all outcomes, an overall decrease of 19%. mRNA-1273 vaccine effectiveness was highest in the pre-Delta (93.5%; 95% CI, 91.9%-94.7%) and Delta (79.4%; 95% CI, 78.3%-80.4%) periods for all outcomes, whereas the JNJ-78436735 vaccine had the lowest effectiveness during the pre-Delta (81.8%; 95% CI, 74.2%- 87.1%) and Delta (38.3%; 95% CI, 34.5%-41.9%) periods. Effectiveness for all vaccines during both periods was higher for symptomatic infection and hospitalization among individuals with SARS-CoV-2 infection. Conclusions and Relevance: In this case-control study, among US military personnel, COVID-19 vaccine effectiveness was significantly lower during the period when the Delta variant predominated compared with the period before Delta variant predominance; this was especially true for the JNJ-78436735 vaccine. These findings were confounded by time since vaccination; this and the change in effectiveness support the need for booster doses and continued evaluation of vaccine effectiveness as new variants of SARS-CoV-2 emerge.

COVID-19 and depressive symptoms among active component U.S. service members, January 2019-July 2021.

This study examined the rates of depressive symptoms in active component U.S. service members prior to and during the COVID-19 pandemic and evaluated whether SARS-CoV-2 test results (positive or negative) were associated with self-reported depressive symptoms. Depressive symptoms were measured by the Patient Health Questionnaire-2 (PHQ-2) screening instrument and were defined as positive if the total score was 3 or greater. From 1 January 2019 through 31 July 2021, 2,313,825 PHQ-2s were completed with an increase in the positive rate from 4.0% to 6.5% (absolute % difference, +2.5%; relative % change, +67.1%) from the beginning to the end of the period. While there was a gradual increase of 19.8% in the months prior to the pandemic (1.4%/month average), this increase grew to 40.4% during the pandemic (2.5%/month average). However, no association was found between a positive or negative SARS-CoV-2 test result and the PHQ-2 screening instrument result. These findings suggest that the accelerated increase in depressive symptoms is likely a function of the environment of the COVID-19 pandemic instead of the SARS-CoV-2 infection itself. Further research to better understand specific factors of the pandemic leading to depressive symptoms will improve efficient allocation of military medical resources and safeguard military medical readiness.

Proteomic identification of altered apolipoprotein patterns in pulmonary hypertension and vasculopathy of sickle cell disease.

Pulmonary arterial hypertension (PAH) is emerging as a major complication and independent risk factor for death among adults with sickle cell disease (SCD). Using surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF MS), we searched for biomarkers of PAH in plasma specimens from 27 homozygous sickle cell anemia (HbSS) patients with PAH and 28 without PAH. In PAH patients, analysis consistently showed lower abundance of a 28.1-kDa peak (P < .001), identified by high-resolution mass spectrometry as the oxidant-scavenging protein apolipoprotein A-I (apoA-I), which correlated with clinical assays of apoA-I (r = .58, P < .001) and high-density lipoprotein (HDL) levels (r = .50, P = .001). Consistent with endothelial dysfunction that may mediate this effect in PAH, HbSS patients with lower apoA-I levels also displayed impaired vasodilatory responses to acetylcholine (mean +/- SEM, 189% +/- 34% [n = 13] vs 339% +/- 51% [n = 13], P < .001). As a group, patients with SCD demonstrated significantly lower apoA-I levels than African-American control subjects. The PAH cohort was further characterized by high levels of apolipoproteins A-II and B and serum amyloid A, and low levels of haptoglobin dimers and plasminogen. These results imply a relationship of apolipoproteins to the development of PAH vasculopathy in SCD, potentially involving an unexpected mechanistic parallel to atherosclerosis, another proliferative vasculopathy.

Update: Osteoarthritis and Spondylosis, Active Component, U.S. Armed Forces, 2016-2020.

Osteoarthritis (OA) is the most common adult joint disease and accounts for significant morbidity burdens among U.S. civilian and military populations. During 2016-2020, the crude overall rates of incident OA and spondylosis diagnoses among U.S. active component service members were 630.9 per 100,000 person-years (p-yrs) and 958.2 per 100,000 p-yrs, respectively. Crude annual rates of both conditions decreased markedly from 2016 through 2020 with declines evident in all of the demographic and military subgroups examined. Compared to their respective counterparts, crude overall rates of OA diagnoses were highest among male service members, those aged 35 or older, non-Hispanic Black service members, Army members, and those working in health care occupations. Crude overall rates of spondylosis diagnoses were highest among those aged 30 or older, non-Hispanic White and non-Hispanic Black service members, Army members, and those in health care and communications/intelligence occupations. More than two-thirds of all incident OA diagnoses involved the knee (38.8%) or shoulder (28.4%). Differences in anatomic site-specific rates of OA were apparent by sex, race/ethnicity group, service, and military occupation. Additional research to identify military-specific equipment and activities that increase the risk of acute and chronic damage to joints would be useful to develop, test, and implement practical and effective countermeasures against OA and spondylosis among military members in general and those in high-risk occupations specifically.

Protein expression profiles distinguish between experimental invasive pulmonary aspergillosis and Pseudomonas pneumonia.

We hypothesized that invasive pulmonary aspergillosis (IPA) may generate a distinctive proteomic signature in plasma and bronchoalveolar lavage (BAL). Proteins in plasma and BAL from two neutropenic rabbit models of IPA and Pseudomonas pneumonia were analyzed by SELDI-TOF MS. Hierarchical clustering analysis of plasma time course spectra demonstrated two clusters of peaks that were differentially regulated between IPA and Pseudomonas pneumonia (57 and 34 peaks, respectively, p<0.001). PCA of plasma proteins demonstrated a time-dependent separation of the two infections. A random forest analysis that ranked the top 30 spectral points distinguished between late Aspergillus and Pseudomonas pneumonias with 100% sensitivity and specificity. Based on spectral data analysis, three proteins were identified using SDS-PAGE and LC/MS and quantified using reverse phase arrays. Differences in the temporal sequence of plasma haptoglobin (p<0.001), apolipoprotein A1 (p<0.001) and transthyretin (p<0.038) were observed between IPA and Pseudomonas pneumonia, as was C-reactive protein (p<0.001). In summary, proteomic analysis of plasma and BAL proteins of experimental Aspergillus and Pseudomonas pneumonias demonstrates unique protein profiles with principal components and spectral regions that are shared in early infection and diverge at later stages of infection. Haptoglobin, apolipoprotein A1, transthyretin, and C-reactive protein are differentially expressed in these infections suggesting important contributions to host defense against IPA.

Summary of the 2018-2019 influenza season among Department of Defense service members and other beneficiaries.

The Armed Forces Health Surveillance Branch conducts weekly surveillance of influenza activity among Department of Defense (DoD) populations each influenza season. This report provides a summary of the data from the 2018-2019 influenza season. Ambulatory data for influenza-like illnesses (ILIs), influenza hospitalization data, and lab data for influenza-confirmed cases were used for the surveillance. The 2018-2019 season differed from past seasons in that it was much longer, had a later peak, and the predominant strain of influenza changed from influenza A(H1N1)pdm09 at the beginning of the season to influenza A(H3N2) in the middle of the season. Non-service member beneficiaries accounted for the majority of ILI-related encounters and hospitalizations. However, there were still 149 influenza-related hospitalizations among service members during the 2018- 2019 season. Continued weekly surveillance of influenza among DoD populations is crucial to track increases in activity each season and the potential emergence of new and/or severe influenza subtypes.

Acute and chronic pancreatitis, active component, U.S. Armed Forces, 2004-2018.

Pancreatitis is an inflammatory disease of the pancreas resulting from the premature activation of digestive enzymes within the pancreas. Pancreatitis occurs in both acute and chronic forms. During 2004-2018, a total of 6,471 U.S. active component service members received incident diagnoses of acute pancreatitis (AP), for a crude overall incidence rate of 31.8 per 100,000 person- years (p-yrs). Compared to their respective counterparts, overall rates of AP diagnoses were highest among females, those in older age groups, non-Hispanic blacks, Army members, and those working in healthcare occupations. Crude annual rates of AP diagnoses increased by 25.5% over the 15-year period; this trend was driven largely by a rise in outpatient rates. Of the total incident cases of AP, 9.0% received a subsequent incident diagnosis of chronic pancreatitis (CP) during the surveillance period. Between 2004 and 2018, the crude overall incidence rate of CP was 4.4 per 100,000 p-yrs. Patterns of overall rates of CP by demographic and military characteristics were generally similar to those for AP. Crude annual rates of CP fluctuated between 3.7 per 100,000 p-yrs and 5.7 per 100,000 p-yrs during the surveillance period, with no pronounced overall trend over time. To inform preventive and therapeutic strategies, continued research is needed to understand the factors that increase risk of progression from AP to CP and the importance of the interaction between genetic and environmental factors in this transition.

Vasectomy and vasectomy reversals, active component, U.S. Armed Forces, 2000-2017.

During 2000-2017, a total of 170,878 active component service members underwent a first-occurring vasectomy, for a crude overall incidence rate of 8.6 cases per 1,000 person-years (p-yrs). The most common operative procedure performed was conventional vasectomy (99.2%), with less than 1% of vasectomies categorized as minimally invasive vasectomy. Among the men who underwent incident vasectomy, 2.2% had another vasectomy performed during the surveillance period. Compared to their respective counterparts, the overall rates of vasectomy were highest among service men aged 30-39 years, non-Hispanic whites, married men, and those in pilot/air crew occupations. Male Air Force members had the highest overall incidence of vasectomy and men in the Marine Corps, the lowest. Crude annual vasectomy rates among service men increased slightly between 2000 and 2017. The largest increases in rates over the 18-year period occurred among service men aged 35-49 years and among men working as pilots/air crew. Among those who underwent vasectomy, 1.8% also had at least 1 vasectomy reversal during the surveillance period. The likelihood of vasectomy reversal decreased with advancing age. Non-Hispanic black and Hispanic service men were more likely than those of other race/ethnicity groups to undergo vasectomy reversals.

Herpes zoster, active component, U.S. Armed Forces, 2000-2016.

During 2000-2016, a total of 52,895 active component service members received incident diagnoses of herpes zoster (HZ), for an overall unadjusted incidence rate of 2.5 cases per 1,000 person-years (p-yrs). Compared to their respective counterparts, overall incidence rates of HZ were highest among females, those aged 50 years or older, and Air Force members. Overall rates generally increased with increasing age and were highest among non-Hispanic whites and Asian/Pacific Islanders and lowest among non-Hispanic blacks. Unadjusted annual incidence rates of HZ increased steadily from 2000 to a peak in 2014. From 2000 through 2016, annual rates of HZ increased in each service and increases in annual rates were seen in all race/ethnicity groups. Individuals who were identified as immunocompromised constituted 2.1% of the total incident HZ cases. During 2000-2016, the cumulative numbers of incident cases of HZ were highest during June, July, and August. The increase in HZ incidence observed in this and many other studies is a public health concern that requires a better understanding of key risk factors. Additional research focused on these factors could make trends more interpretable, suggest new approaches for prevention and treatment of HZ, and allow for better targeting of existing strategies.

Psychiatric medical evacuations in individuals with diagnosed pre-deployment family problems, active component, U.S. Armed Forces, 2002-2014.

This study evaluated incidence of pre-deployment family problem diagnoses and psychiatric medical evacuations among a population of active component service members without a history of previous mental health diagnoses, who deployed to the U.S. Central Command Area of Responsibility for the first time between 1 January 2002 and 31 December 2014. During the surveillance period, 6,182 service members received an incident family problems diagnosis during the pre-deployment period, with an overall incidence of 5.6 cases per 1,000 deployers. The incidence of pre-deployment family problem diagnoses was generally stable over the study period. Compared to their respective counterparts, rates of pre-deployment family problems were highest among females, non-Hispanic black service members, those who were married, enlisted service members, and Army members. A total of 2,190 active component service members were evacuated from theater for psychiatric reasons, with an overall incidence rate of 3.1 per 1,000 deployed person-years. Of evacuated service members, 1.7% had diagnosed pre-deployment family problems (N=38). Incidence of psychiatric medical evacuation was consistently higher among those with pre-deployment family problems among all demographic subgroups, and overall was 2.7 times the incidence among those without documented family problems.

Seizures among active component service members, U.S. Armed Forces,2007-2016.

Traumatic brain injury (TBI) is a known risk factor for seizures. Evidence also shows that post-traumatic stress disorder (PTSD) is associated with seizures, but the relationship in the absence of TBI remains unclear. This retrospective study spanning 2007-2016 separately quantifies the rates of seizures diagnosed among deployed and non-deployed active component military service members to understand the factors associated with seizures and whether they differ in deployed settings. Higher rates of seizures were associated with service members who were in the Army or Marine Corps; female; black; younger; lower enlisted; in a combat-specific, armor/motor transport, or healthcare occupation; and who had no more than one previous deployment. These associations were similar among both deployed and non-deployed service members. Either a TBI or recent PTSD diagnosis was associated with a 3- to 4-fold increased seizure rate. For service members who had received both diagnoses, seizure rates among the deployed and the non-deployed were two and three times the rates among those with only one of those diagnoses, respectively. If the current results are supported by future investigations, there may be implications for both clinical care and military policy.

Fatigue and related comorbidities, active component, U.S. Armed Forces, 2007-2016.

Fatigue is a common complaint in the civilian population and may be a presenting symptom of more serious physical and mental disorders. Data from the Defense Medical Surveillance System (DMSS) were utilized to characterize the incidence and burden of fatigue in active component military members from 1 January 2007 through 31 December 2016. A subanalysis of 3 years within this surveillance period (2012-2014) was also conducted to assess the burden of comorbidities related to incident fatigue and the strength of the association between fatigue and selected comorbidities. The study identified 211,213 incident cases of fatigue with an overall incidence rate of 18.1 per 1,000 person-years between 2007 and 2016. Mental disorders and musculoskeletal disease accounted for about 35% of all medical encounters and about 40% of all hospital days within a year for those diagnosed with fatigue in 2013. The adjusted odds ratio for fatigue was highest in those with male hypogonadism, thyroid disorder, and sleep problems. These results show that fatigue is a common diagnosis with high incidence and burden among active component U.S. military. By focusing on the conditions that frequently occur and are highly associated with fatigue, more rapid diagnosis and treatment of the underlying cause of service member fatigue is possible.