Association of elevated lipoprotein(a) levels with ischemic stroke in young patients - a systematic review and meta-analysis.

INTRODUCTION: Lipoprotein(a) [Lp(a)] is an established independent causal risk factor for cardiovascular disease and atherosclerosis. However, its association with young-onset ischemic stroke is not well-established. A systematic review and meta-analysis was performed to investigate the association of elevated Lp(a) with young ischemic stroke. METHODS: Four electronic databases: PubMed (MEDLINE), EMBASE, Scopus and Cochrane Library were systematically searched, profiling studies from inception till 6 Mar 2024. We included studies investigating the relationship between stratified Lp(a) levels and young ischemic stroke. We compared the odds of young stroke patients (age <65 years) having elevated Lp(a) compared to age-matched controls without stroke or transient ischemic attack. RESULTS: Five case-control studies comprising a total of 1345 patients were included; 57.7% (776/1345) were females, with a mean age of 41.5 years. Among them, 22.5% (264/1171) were smokers. Additionally, 16.8% (197/1171) had hypertension, 5.9% (69/1171) had diabetes, and 29.2% (284/971) had hyperlipidemia. Young stroke patients were more likely to have high Lp(a) level than age-matched controls (OR 1.61, 95%CI 1.24-2.10). Four studies defined a high Lp(a) level as ≥30mg/dL, whilst one study used a Lp(a) level of >23.2mg/dL as the cut-off. A sensitivity analysis excluding this study showed that young stroke patients were still more likely to have Lp(a) ≥30mg/dL than controls (OR 1.43, 95%CI 1.08-1.88). CONCLUSION: Young stroke patients are more likely to have elevated Lp(a) compared to age-matched controls, suggesting an association between elevated Lp(a) and young stroke. Further research is warranted to evaluate the causal relationships between Lp(a) and young-onset ischemic stroke, as well as to conduct a cost-benefit analysis of Lp(a) screening in young adults as part of a primary prevention strategy.

Systematic Review of Clinical Practice Guidelines for Insomnia Disorder.

OBJECTIVE: This systematic review assessed the quality of clinical practice guidelines (CPGs) on the treatment of insomnia disorder and their reporting of recommendations, while summarizing the evidence and providing guidance on an algorithmic approach to appropriate pharmacological treatment. METHODS: The PubMed and EMBASE databases, guideline repositories, and specialist association websites were searched. The quality of the CPGs was assessed using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument, complemented by the AGREE-REX (Appraisal of Guidelines REsearch and Evaluation-Recommendations EXcellence). A multidisciplinary team identified the key clinical questions that a clinician would consider when taking an algorithmic approach to the use of medication for patients with insomnia disorder. By using a meta-synthesis approach, recommendations from the CPGs were characterized and summarized via a recommendation matrix. RESULTS: A total of 10 records that met the inclusion criteria were included and appraised. Four CPGs were rated as high and 3 CPGs were rated as moderate in overall quality. Most of the CPGs recommended pharmacotherapy only if cognitive behavioral therapy for insomnia or other nonpharmacological interventions were unavailable, unsuccessful, or declined by patients. Recommendations on types of medicines and dose and duration of treatment varied and were nonspecific. Few of the CPGs provided recommendations on pharmacotherapy in special populations. CONCLUSIONS: Indications for starting medications are the only common thread in all of the reviewed CPGs. The CPGs diverged in the choice of first-line pharmacotherapy, and most of the CPGs did not provide recommendations on all subsequent clinical considerations.

Development of cytomegalovirus (CMV) immune recovery uveitis is associated with Th17 cell depletion and poor systemic CMV-specific T cell responses.

BACKGROUND: the immune reconstitution inflammatory syndromes (IRIS) are a spectrum of inflammatory conditions associated with opportunistic infections and occurring in approximately16% of human immunodeficiency type 1 (HIV-1)-infected patients given antiretroviral therapy. It has been proposed that these conditions are linked by a dysregulated immune system that is prone to exaggerated responses. However, immunologic studies have been limited by the availability of longitudinal samples from patients with IRIS and appropriate matched control subjects. Cytomegalovirus (CMV) immune recovery uveitis (IRU) is an IRIS occurring in up to 38% of patients with CMV retinitis. Although the pathologic immune responses occur in the eye, immune dysregulation that allows for development of pathologic responses is presumably caused by faulty systemic immune cell reconstitution. METHODS: we examined CMV-specific T cell responses, regulatory T (T(reg)) cell function and polyclonal T cell responses, including IL-17 production, in 25 patients with CMV IRU and 49 immunorestored control subjects with CMV retinitis who did not develop IRU. RESULTS: patients with CMV IRU had poor CMV-specific CD4(+) T cell responses, as compared with control subjects, whereas CD8(+) T cell responses were comparable. Patients with CMV IRU were characterized by smaller numbers of circulating Th17 cells. Deficiency in anti-CMV responses was not associated with differences in T(reg) cell function. CONCLUSIONS: the T(reg) cell compartment is intact in patients with CMV IRU, and these patients do not develop exaggerated systemic CMV-specific or polyclonal immune responses. Cases are instead characterized by more profound depletion of Th17 cells and poor antiviral immune responses. CMV IRU may be most likely to develop in persons experiencing the greatest degree of immune dysfunction before initiating highly active antiretroviral therapy.

IL-2 immunotherapy to recently HIV-1 infected adults maintains the numbers of IL-17 expressing CD4+ T (T(H)17) cells in the periphery.

Little is known about the manipulation of IL-17 producing CD4+ T cells (T(H)17) on a per-cell basis in humans in vivo. Previous studies on the effects of IL-2 on IL-17 secretion in non-HIV models have shown divergent results. We hypothesized that IL-2 would mediate changes in IL-17 levels among recently HIV-1-infected adults receiving anti-retroviral therapy. We measured cytokine T cell responses to CD3/CD28, HIV-1 Gag, and CMV pp65 stimulation, and changes in multiple CD4+ T cell subsets. Those who received IL-2 showed a robust expansion of naive and total CD4+ T cell counts and T-reg counts. However, after IL-2 treatment, the frequency of T(H)17 cells declined, while counts of T(H)17 cells did not change due to an expansion of the CD4+ naïve T cell population (CD27+CD45RA+). Counts of HIV-1 Gag-specific T cells declined modestly, but CMV pp65 and CD3/CD28 stimulated populations did not change. Hence, in contrast with recent studies, our results suggest IL-2 is not a potent in vivo regulator of T(H)17 cell populations in HIV-1 disease. However, IL-2-mediated T-reg expansions may selectively reduce responses to certain antigen-specific populations, such as HIV-1 Gag.

Poor predictive value of cytomegalovirus (CMV)-specific T cell assays for the development of CMV retinitis in patients with AIDS.

BACKGROUND: We examined the potential clinical utility of using a cytomegalovirus (CMV)-specific T cell immunoassay to determine the risk of developing new-onset CMV retinitis (CMVR) in patients with acquired immunodeficiency syndrome (AIDS). METHODS: CMV-specific T cell assays were performed by multiparameter flow cytometry using stored peripheral blood mononuclear cells that had been obtained in an observational study 2-6 months before new-onset CMVR was diagnosed in case patients (at a study visit during which a dilated ophthalmologic examination revealed no evidence of CMVR) and at the same study visit in control subjects (matched by absolute CD4(+) T cell count at entry) who did not subsequently develop retinitis during 1-6 years of study follow-up. RESULTS: There were no significant differences in CMV-specific CD4(+) or CD8(+) T cell interferon-gamma or interleukin-2 expression in peripheral blood mononuclear cells from case patients and control subjects. Although there were trends toward lower percentages and absolute numbers of CMV-specific, cytokine-expressing CD8(+) T cells with a "late memory" phenotype (CD27(-)CD28(-)) as well as with an "early memory" phenotype (CD27(+)CD28(+)CD45RA(+)) in case patients than in control subjects, these differences were not statistically significant. CONCLUSIONS: Many studies have reported that CMV-specific CD4(+) and CD8(+) T cell responses distinguish patients with active CMVR (i.e., who lack CMV-protective immunity) from those with inactive CMVR after immune restoration by antiretroviral treatment (i.e., who have CMV-protective immunity). However, the multiple CMV-specific immune responses we measured do not appear to have clinical utility for predicting the risk for patients with AIDS of developing new-onset CMVR with sufficient accuracy to be used in guiding therapeutic management.

Loss of T cell responses following long-term cryopreservation.

Although cryopreservation of peripheral blood mononuclear cells (PBMC) is a commonly used technique, the degree to which it affects subsequent functional studies has not been well defined. Here we demonstrate that long-term cryopreservation has detrimental effects on T cell IFN-gamma responses in human immunodeficiency virus (HIV) infected individuals. Long-term cryopreservation caused marked decreases in CD4(+) T cell responses to whole proteins (HIV p55 and cytomegalovirus (CMV) lysate) and HIV peptides, and more limited decreases in CD8(+) T cell responses to whole proteins. These losses were more apparent in cells stored for greater than one year compared to less than six months. CD8(+) T cell responses to peptides and peptide pools were well preserved. Loss of both CD4(+) and CD8(+) T cell responses to CMV peptide pools were minimal in HIV-negative individuals. Addition of exogenous antigen presenting cells (APC) did not restore CD4(+) T cell responses to peptide stimulation and partially restored T cell IFN-gamma responses to p55 protein. Overnight resting of thawed cells did not restore T cell IFN-gamma responses to peptide or whole protein stimulation. A selective loss of phenotypically defined effector cells did not explain the decrement of responses, although cryopreservation did increase CD4(+) T cell apoptosis, possibly contributing to the loss of responses. These data suggest that the impact of cryopreservation should be carefully considered in future vaccine and pathogenesis studies. In HIV-infected individuals short-term cryopreservation may be acceptable for measuring CD4(+) and CD8(+) T cell responses. Long-term cryopreservation, however, may lead to the loss of CD4(+) T cell responses and mild skewing of T cell phenotypic marker expression.

Protective immunity to cytomegalovirus (CMV) retinitis in AIDS is associated with CMV-specific T cells that express interferon- gamma and interleukin-2 and have a CD8+ cell early maturational phenotype.

To determine potential correlates of immune recovery from AIDS-related cytomegalovirus retinitis (CMVR), multiparameter flow cytometry was used to characterize CMV-specific T cells from subjects with CMVR. Individuals with active retinitis were compared with those who had been clinically immunorestored by antiretroviral therapy and had > or =2 years of ophthalmologic follow-up without anti-CMV therapy or retinitis reactivation or progression. In comparison with patients with active retinitis, immunorestored patients had higher circulating CD4(+) and CD8(+) T cells expressing interleukin-2 and interferon- gamma in response to combined CMV pp65 and IE1 peptide pool stimulation. CD4(+) T cell responses were predominantly to pp65, whereas CD8(+) T cell responses were predominantly to IE. Immunorestored patients, compared with patients with active retinitis, had increased levels of circulating CMV-specific CD8(+) T cells with "early" (CD27(+)CD28(+)CD45RA(+), CD27(+)CD28(+)CD45RA(-)) and "intermediate" (CD27(-)CD28(+)CD45RA(-)) phenotypes. Recovery from AIDS-related CMVR after the initiation of antiretroviral therapy may be mediated by CMV-specific CD4(+) and CD8(+) T cells capable of promoting antigen-specific CD8(+) T cell proliferation.