Pharmacotherapy for hypertension-induced left ventricular hypertrophy

BACKGROUND

Hypertension is the leading preventable risk factor for cardiovascular disease and premature death worldwide. One of the clinical effects of hypertension is left ventricular hypertrophy (LVH), a process of cardiac remodelling. It is estimated that over 30% of people with hypertension also suffer from LVH, although the prevalence rates vary according to the LVH diagnostic criteria. Severity of LVH is associated with a higher prevalence of cardiovascular disease and an increased risk of death. The role of antihypertensives in the regression of left ventricular mass has been extensively studied. However, uncertainty exists regarding the role of antihypertensive therapy compared to placebo in the morbidity and mortality of individuals with hypertension-induced LVH.

OBJECTIVES

To assess the effect of antihypertensive pharmacotherapy compared to placebo or no treatment on morbidity and mortality of adults with hypertension-induced LVH.

SEARCH METHODS

Cochrane Hypertension's Information Specialist searched the following databases for studies: Cochrane Hypertension Specialised Register (to 26 September 2020), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library; 2020, Issue 9), Ovid MEDLINE (1946 to 22 September 2020), and Ovid Embase (1974 to 22 September 2020). We searched the World Health Organization International Clinical Trials Registry Platform and the ClinicalTrials.gov for ongoing trials. We also searched Epistemonikos (to 19 February 2021), LILACS BIREME (to 19 February 2021), and Clarivate Web of Science (to 26 February 2021), and contacted authors and funders of the identified trials to obtain additional information and individual participant data. There were no language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) with at least 12 months' follow-up comparing antihypertensive pharmacological therapy (monotherapy or in combination) with placebo or no treatment in adults (18 years of age or older) with hypertension-induced LVH were eligible for inclusion. The trials must have analysed at least one primary outcome (all-cause mortality, cardiovascular events, or total serious adverse events) to be considered for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors screened the search results, with any disagreements resolved by consensus amongst all review authors. Two review authors carried out the data extraction and analyses. We assessed risk of bias of the included studies following Cochrane methodology. We used the GRADE approach to assess the certainty of the body of evidence.

MAIN RESULTS

We included three multicentre RCTs. We selected 930 participants from the included studies for the analyses, with a mean follow-up of 3.8 years (range 3.5 to 4.3 years). All of the included trials performed an intention-to-treat analysis. We obtained evidence for the review by identifying the population of interest from the trials' total samples. None of the trials provided information on the cause of LVH. The intervention varied amongst the included trials: hydrochlorothiazide plus triamterene with the possibility of adding alpha methyldopa, spironolactone, or olmesartan. Placebo was administered to participants in the control arm in two trials, whereas participants in the control arm of the remaining trial did not receive any add-on treatment. The evidence is very uncertain regarding the effect of additional antihypertensive pharmacological therapy compared to placebo or no treatment on mortality (14.3% intervention versus 13.6% control; risk ratio (RR) 1.02, 95% confidence interval (CI) 0.74 to 1.40; 3 studies; 930 participants; very low-certainty evidence); cardiovascular events (12.6% intervention versus 11.5% control; RR 1.09, 95% CI 0.77 to 1.55; 3 studies; 930 participants; very low-certainty evidence); and hospitalisation for heart failure (10.7% intervention versus 12.5% control; RR 0.82, 95% CI 0.57 to 1.17; 2 studies; 915 participants; very low-certainty evidence). Although both arms yielded similar results for total serious adverse events (48.9% intervention versus 48.1% control; RR 1.02, 95% CI 0.89 to 1.16; 3 studies; 930 participants; very low-certainty evidence) and total adverse events (68.3% intervention versus 67.2% control; RR 1.07, 95% CI 0.86 to 1.34; 2 studies; 915 participants), the incidence of withdrawal due to adverse events may be significantly higher with antihypertensive drug therapy (15.2% intervention versus 4.9% control; RR 3.09, 95% CI 1.69 to 5.66; 1 study; 522 participants; very low-certainty evidence). Sensitivity analyses limited to blinded trials, trials with low risk of bias in core domains, and trials with no funding from the pharmaceutical industry did not change the results of the main analyses. Limited evidence on the change in left ventricular mass index prevented us from drawing any firm conclusions.

AUTHORS' CONCLUSIONS

We are uncertain about the effects of adding additional antihypertensive drug therapy on the morbidity and mortality of participants with LVH and hypertension compared to placebo. Although the incidence of serious adverse events was similar between study arms, additional antihypertensive therapy may be associated with more withdrawals due to adverse events. Limited and low-certainty evidence requires that caution be used when interpreting the findings. High-quality clinical trials addressing the effect of antihypertensives on clinically relevant variables and carried out specifically in individuals with hypertension-induced LVH are warranted.

Why doesn't emotional valence affect subitising and counting in simple enumeration?

Accurate visual-spatial enumeration involves either the subitising process (for 1-4 items) or the counting process (for larger numbers of items). Although these processes differ, both are thought to involve attentional selection. Many studies show that emotional valence, the negativity or positivity of a stimulus, influences attention and yet Watson and Blagrove found valence had no effect on simple enumeration (enumeration without distractors). To shed light on this surprising finding, we had participants enumerate 1 to 9 dots after viewing emotional scenes, using images from the International Affective Picture System (IAPS) to manipulate valence and arousal. To ensure valence and arousal categorisations were valid for each participant, we individualised them based on their own ratings. Results indicated that both valence and arousal affected enumeration latencies, with enumeration fastest after positive high arousal images and slowest after negative low arousal images. Disengagement deficits were apparent from slowed enumeration after negative images, but there was no evidence that valence affected the breadth of the attentional focus (no interactions with display area). Despite hints that valence may affect subitising and counting differently (weak trends to a cross-over interaction in RT slopes), no firm conclusions can be made because differences were small (<20 ms/item).

p63/MT1-MMP axis is required for in situ to invasive transition in basal-like breast cancer

The transition of ductal carcinoma in situ (DCIS) to invasive breast carcinoma requires tumor cells to cross the basement membrane (BM). However, mechanisms underlying BM transmigration are poorly understood. Here, we report that expression of membrane-type 1 (MT1)-matrix metalloproteinase (MMP), a key component of the BM invasion program, increases during breast cancer progression at the in situ to invasive breast carcinoma transition. In the intraductal xenograft model, MT1-MMP is required for BM transmigration of MCF10DCIS.com breast adenocarcinoma cells and is overexpressed in cell clusters overlying focal BM disruptions and at the invasive tumor front. Mirrored upregulation of p63 and MT1-MMP is observed at the edge of MCF10DCIS.com xenograft tumors and p63 is required for induction of MT1-MMP-dependent invasive program in response to microenvironmental signals. Immunohistochemistry and analysis of public database reveal that p63 and MT1-MMP are upregulated in human basal-like breast tumors suggesting that p63/MT1-MMP axis contributes to progression of basal-like breast cancers with elevated p63 and MT1-MMP levels.

Immunological responses and protective immunity against tuberculosis conferred by vaccination of Balb/C mice with the attenuated Mycobacterium tuberculosis (phoP) SO2 strain

The Mycobacterium tuberculosis phoP mutant strain SO2 has been shown previously to be more attenuated than Mycobacterium bovis bacillus Calmette-Guérin (BCG) and confers protective immunity against tuberculosis in mice and guinea pig models. In this study we have investigated the survival and immunological responses of Balb/c mice infected with the M. tuberculosis SO2 strain. All Balb/C mice survived intratracheal infection with M. tuberculosis SO2 strain under conditions where all the mice infected with the parental M. tuberculosis MT103 had died after 9 weeks. Infection of Balb/c mice with M. tuberculosis SO2 was associated with comparatively lower levels of interferon (IFN)-gamma, interleukin (IL)-4 and tumour necrosis factor (TNF)-alpha and higher levels of inducible nitric oxide synthase (iNOS) during the late stage of infection, when compared with M. tuberculosis MT103 infection. The delayed-type hypersensitivity (DTH) response against M. tuberculosis culture filtrates was similar in mice infected with either the M. tuberculosis phoP SO2 strain or M. tuberculosis MT103. The protective efficacy of M. tuberculosis SO2 was compared with M. bovis BCG when delivered subcutaneously to groups of Balb/C mice. Following intratracheal challenge with M. tuberculosis H37Rv, protection was generated by 60 days post-challenge in mice vaccinated with either vaccine. At day 120 post-challenge the levels of protection were still significantly greater when compared with the non-vaccinated control group. The levels of protection conferred by vaccination with M. tuberculosis SO2 or with M. bovis BCG were similar, as measured by granuloma coalescence and pneumonia in addition to growth reduction of M. tuberculosis H37Rv.

The use of mutant mycobacteria as new vaccines to prevent tuberculosis

Given the variable protective efficacy generated by Mycobacterium bovis BCG (Bacillus Calmette-Guérin), there is a concerted effort worldwide to develop better vaccines that could be used to reduce the burden of tuberculosis. Rational attenuated mutants of Mycobacterium tuberculosis are vaccine candidates that offer some potential in this area. In this paper, we will discuss the molecular methods used to generate mutant mycobacteria, as well as the results obtained with some of these strains, in terms of attenuation, immunogenicity and level of protection, when compared with the conventional BCG vaccine in diverse animal models. Tuberculosis vaccine candidates based on safe and live mycobacterial mutants could be promising candidates.

Immunogenicity and protection induced by Mycobacterium tuberculosis mce-2 and mce-3 mutants in a Balb/c mouse model of progressive pulmonary tuberculosis

Mycobacterial proteins coded by the mammalian cell entry (mce) genes allow for cell invasion into the host. The Mycobacterium tuberculosismce-2 and mce-3 mutants have impaired synthesis of mce proteins and are attenuated in BALB/c mice. Intra-tracheal infection of Balb/c mice with either mce mutant induced lower but progressive production of IFN-gamma and TNF-alpha, as well as larger delayed type hypersensitivity (DTH) reactions, than their parental H37Rv strain. When used as a subcutaneous vaccine and, before challenge, both mutants were more attenuated than BCG in Balb/c and immunodeficient nude mice. Cell suspensions from lymph nodes and spleen from mce mutant vaccinated mice stimulated with mycobacterial culture filtrate antigens (CFA) or immunodominant antigens (ESAT-6, Ag85) produced more INF-gamma than BCG-vaccinated animals. Used as subcutaneous vaccines, 60 days before intra-tracheal challenge with the hypervirulent strain of M. tuberculosis (Beijing code 9501000), both mutants induced a higher level of protection than BCG; 72% and 63% of the mice vaccinated with the mce-2 and mce-3 mutants, respectively, survived for 16 weeks after the challenge as compared to 30% of those vaccinated with BCG. Likewise, there was less tissue damage (pneumonia) and lower colony forming units (CFU) in the mice vaccinated with either of the two mutants as compared to the findings in mice vaccinated with BCG. These data suggest that lack of mce-2 and -3 gene expression decreases virulence and increases immunogenicity of live vaccines, favouring their ability to protect against tuberculosis, which was better than the protection conferred by BCG.

Immunogenicity and protective efficacy of the Mycobacterium tuberculosis fadD26 mutant

The Mycobacterium tuberculosis fadD26 mutant has impaired synthesis of phthiocerol dimycocerosates (DIM) and is attenuated in BALB/c mice. Survival analysis following direct intratracheal infection confirmed the attenuation: 60% survival at 4 months post-infection versus 100% mortality at 9 weeks post-infection with the wild-type strain. The fadD26 mutant induced less pneumonia and larger DTH reactions. It induced lower but progressive production of interferon (IFN)-gamma, interleukin (IL)-4 and tumour necrosis factor (TNF)-alpha. Used as a subcutaneous vaccine 60 days before intratracheal challenge with a hypervirulent strain of M. tuberculosis (Beijing code 9501000), the mutant induced a higher level of protection than did Bacille Calmette-Guérin (BCG). Seventy per cent of the mice vaccinated with the fadD26 mutant survived at 16 weeks after challenge compared to 30% of those vaccinated with BCG. Similarly, there was less tissue damage (pneumonia) and lower colony-forming units (CFU) in the mice vaccinated with the fadD26 mutant compared to the findings in mice vaccinated with BCG. These data suggest that DIM synthesis is important for the pathogenicity of M. tuberculosis, and that inactivation of DIM synthesis can increase the immunogenicity of live vaccines, and increase their ability to protect against tuberculosis.

Molecular analysis of HLA-DRB1, DQA1, DQB1, DQ promoter polymorphism and extended class I/class II haplotypes in the Seri Indians from Northwest Mexico

The study of the genetics of the Major Histocompatibility Complex (MHC) in Amerindians is of great value in understanding the origins and migrations of these native groups, as well as the impact of immunogenetics on the epidemiology of diseases affecting these populations. We analyzed, using Polymerase Chain Reaction and Sequence Specific Oligonucleotide Probes (PCR-SSOP), DRB1, DQA1, DQB1 alleles and the promoter regions of DQA1 and DQB1 genes in 31 unrelated and 24 related Seri, a Mexican Indian group, from the state of Sonora (Northwest Mexico). The class II genotypes of this population were found to be in genetic equilibrium. The allele frequency (AF) of the prevalent DRB1 alleles were DRB1*0407 (48.4%), DRB1*0802 (33.9%) and DRB1*1402 (16.1%). The most frequent DQA1 and DQB1 alleles were DQA1*03011 (AF = 50.00%), DQA1*0401 (AF = 33.87%) and DQA1*0501 (AF = 16.13%); DQB1*0302 (AF = 50.00%), DQB1*0402 (33.87%) and DQB1*0301 (16.13%); which were in combination with DRB1*0407, DRB1*0802 and DRB1*1402, respectively. Three QAP and three QBP alleles were present (QAP 3.1, 4.1, 4.2; QBP 3.1, 3.21, 4.1) associated with the typical published DQA1 and DQB1 alleles. Four class II haplotypes were present in family members: DRB1*0407-QAP-3.1-DQA1*03011-QBP-3.21-DQB1*0302; DRB1*0802-QAP-4.2-DQA1*0401-QBP-4.1-DQB1*0402; DRB1*1402-QAP-4.1-DQA1*0501-QBP-3.1-DQB1*0301 and DRB1*0701-QAP-2.1-DQA1*0201-QBP-2.1-DQB1*0201. The family data were used to confirm extended haplotypes. A total of 21 haplotypes were found when A* and B* loci were also considered. The three most frequent combinations included A*0201-B*3501-DRB1*0407, A*3101-B*5101-DRB1*0802, and A*0201-B*40-DRB1*1402.

The genetic structure of Mexican Mestizos of different locations: tracking back their origins through MHC genes, blood group systems, and microsatellites

Mexican Mestizos, who are the result of the admixture of Spanish, Indian, and Black genes, were analyzed for different systems. Three populations from geographical distinct areas were studied: the north (State of Nuevo Leon ), the center (State of Guanajuato), and the highlands (mainly Mexico City). Ten blood group systems (N = 229), STRs (N = 107), HLA-A*, B*, C* (N = 116-167), and DRB1, DQA1, and DQB1 (N = 40, 101, 160, respectively) were analyzed in the samples of the highlands. The three groups cluster together in the same branch: Mestizos from Venezuela, Mediterranean and Jews close to the cluster of Orientals, followed by Amerindians. All markers demonstrate that Indian genes are strongly represented in the highlands: Di(a), O, D(-)(+), s, A*0201, *0206, B*1539 (*1541), *3902, *3905, *3512, *3517, *4002, *4005, Cw*0801, *0304, *0401 among others. Cw*0501, *1203, *1204, and *1601 are of White ancestry. The most frequent haplotypes *0407-*03011-*0302 and *0802-*0401-*0402 are of Indian descent as well. The center and mainly the north show a more Caucasian and Semitic profile. The results demonstrate the high variability resulting from interethnic admixture, suggesting that this mechanism is the main factor responsible for the large diversity found in urban populations.

Molecular analysis of HLA class I alleles in the Mexican Seri Indians: implications for their origin

The molecular analysis of HLA class I loci has demonstrated that, although, the genetic profile is restricted in Amerindians, several micropolymorphisms may be important in conferring a biological advantage. We analyzed the HLA-A and B genetic profile of Seris, a Mexican Indian tribe living in northwestern Mexico in the state of Sonora. There are presently only 619 individuals. Our study included 100 Seris belonging to nine families. HLA-A and -B loci typing was performed by polymerase chain reaction using an amplification refractory mutation system (PCR-ARMS) on a select group of samples; all of them were typed by polymerase chain reaction using sequence-specific oliogonuoleotide probes (PCR-SSOP) at a low-intermediate resolution level. The correlation between the techniques was 100%. Only five HLA-A alleles and seven HLA-B alleles were found. A*0201, A*68, A*31, A*24, B*3501, B*40, B*51, B*3512 and B*15 were present in over 5% of the individuals. B*27052 was detected in 2%. B27 is absent in any other Mexican Indian groups previously studied. The presence of B27 may be the result of a founder effect due to different waves of southward migrations. The B-locus is more diverse and the prevalent haplotypes were: A*0201-B*3501, A*0201-B*40, A*0201-B*3512, A*31-B*51, A*68-B*3501 and A*68-B*40. This genetic profile is different from the pattern of other Mexicans. The phylogenetic tree suggests that Seris are more closely related to the Warao Indians from Venezuela, who live in a similar ecosystem, and to some groups of Argentina, than they are to the Mexican Lacandones who live in the jungle. These data emphasize the relevance of the interaction between genes and environment.