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Diabetes and hyperlipidaemia are common comorbidities in people with hypertension. Despite similar protective effects on CVD, different classes of antihypertensive drugs have different effects on CVD risk factors, including diabetes, glucose metabolism and lipids. However, these pleiotropic effects have not been assessed in long-term, large randomised controlled trials, especially for East Asians.We used Mendelian randomisation to obtain unconfounded associations of ACE inhibitors, β-blockers (BBs) and calcium channel blockers (CCBs). Specifically, we used genetic variants in drug target genes and related to systolic BP in Europeans and East Asians, and applied them to the largest available genome-wide association studies of diabetes (74,124 cases and 824,006 controls in Europeans, 77,418 cases and 356,122 controls in East Asians), blood glucose levels, HbAAs expected, genetically proxied ACE inhibition, BBs and CCBs were related to lower risk of CAD in both ancestries. Genetically proxied ACE inhibition was associated with a lower risk of diabetes (OR 0.85, 95% CI 0.78-0.93), and genetic proxies for BBs were associated with a higher risk of diabetes (OR 1.05, 95% CI 1.02-1.09). The estimates were similar in East Asians, and were corroborated by systematic review and meta-analyses of randomised controlled trials. In both ancestries, genetic proxies for BBs were associated with lower HDL-cholesterol and higher triacylglycerols, and genetic proxies for CCBs were associated with higher LDL-cholesterol. The estimates were robust to the use of different genetic instruments and analytical methods.Our findings suggest protective association of genetically proxied ACE inhibition with diabetes, while genetic proxies for BBs and CCBs possibly relate to an unfavourable metabolic profile. Developing a deeper understanding of the pathways underlying these diverse associations would be worthwhile, with implications for drug repositioning as well as optimal CVD prevention and treatment strategies in people with hypertension, diabetes and/or hyperlipidaemia.

Background Statins have long been suspected to have pleiotropic effects via thrombotic factors. Randomized controlled trials are too limited to be definitive. We examined the associations of genetically mimicking effects of statins, PCSK9 inhibitors, and alternative lipid targets (in genes LDLR, APOC3, and LPL) on key indicators of coagulation system function, i.e., prothrombin time (PT) and activated partial thromboplastin time (aPTT). Methods We assessed the effect of established genetic mimics of effects of lipid modifiers and alternative lipid treatment targets on PT (n = 58,110) and aPTT (n = 37,767), all transformed to z-scores, using Mendelian randomization taking advantage of Biobank Japan. Ischemic heart disease (IHD) was a control outcome. Results Genetically mimicked effects of statins increased PT by 0.31 standard deviation (SD) per SD increase in low-density lipoprotein (95% confidence interval [CI]: 0.10–0.51) based on rs12916 but did not affect aPTT. Genetically mimicking effects of targeting LDLR increased PT based on rs688 (0.33 SD per SD increase in triglyceride, 95% CI: 0.03–0.63) but did not affect aPTT. Genetically mimicking effects of PCSK9 inhibitors or targeting APOC3 or LPL had no effect on PT or aPTT. Genetically mimicking effects of statins, PCSK9 inhibitors, and alternative lipid targets reduced risk of IHD in Biobank Japan. Conclusion Statins, and possibly targeting LDLR, may also act via a coagulation cascade factor, likely specific to the extrinsic or common pathway. Further elucidation of the mechanistic pathway may facilitate development of new interventions and inform use of statins particularly in relation to use of other anticoagulants.

BackgroundIncreasing childhood adiposity is a global issue requiring potentially local solutions to ensure it does not continue into adulthood. We systematically identified potentially modifiable targets of adiposity at the onset and end of puberty in Hong Kong the most economically developed major Chinese city.MethodsWe conducted an environment-wide association study (EWAS) and an epigenome-wide association study of adiposity to systematically assess associations with body mass index (BMI) and waist-hip ratio (WHR) in Hong Kong’s population-representative “Children of 1997” birth cohort. Univariable linear regression was used to select exposures related to adiposity at ~11.5 years (BMI n≤7,119, WHR n=5,691) and ~17.6 years (n = 3,618) at Bonferroni-corrected significance, and multivariable linear regression to adjust for potential confounders followed by replication (n=308) and CpG by CpG analysis (n=286) at ~23 years. Findings were compared with evidence from randomized controlled trials (RCTs) and Mendelian randomization (MR) studies.ResultsAt ~11.5 and ~17.6 years the EWAS identified 14 and 37 exposures associated with BMI, as well as seven and 12 associated with WHR respectively. Most exposures had directionally consistent associations at ~23 years. Maternal second-hand smoking, maternal weight, and birth weight were consistently associated with adiposity. Diet (including dairy intake and artificially sweetened beverages), physical activity, snoring, binge eating, and earlier puberty were positively associated with BMI at ~17.6 years, while eating before sleep was inversely associated with BMI at ~17.6 years. Findings for birth weight, dairy intake, binge eating, and possibly earlier puberty are consistent with available evidence from RCTs or MR studies We found 21 CpGs related to BMI and 18 to WHR.ConclusionsThese novel insights into potentially modifiable factors associated with adiposity at the outset and the end of puberty could, if causal, inform future interventions to improve population health in Hong Kong and similar Chinese settings.FundingThis study was supported by the Health and Medical Research Fund Research Fellowship, Food and Health Bureau, Hong Kong SAR Government (#04180097). The DNA extraction was supported by CFS-HKU1.

COVID-19 may cause a dysregulation of the immune system and has complex relationships with multiple autoimmune diseases, including rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). However, little is known about their common genetic architecture. We analysed summary-level genetic data from the latest COVID-19 host genetics consortium and consortia on RA and SLE to examine the shared genetic etiology and causal relationship between COVID-19 and RA/SLE. The cross-trait meta-analysis identified 46, 47, and 19 shared genetic loci for severe COVID-19, COVID-19 hospitalization, and SARS-CoV-2 infection with RA, and 19, 24, and 11 shared loci with SLE, respectively. Shared genes were significantly enriched in the spleen, lung, whole blood, and small intestine, and involved in immune function, inflammation and coagulation process. Co-localization analysis identified eight shared loci in TYK2, IKZF3, COL11A2, PSORS1C1, MANEAL and COG6 genes for COVID-19 with RA, and four in CRHR1, FUT2 and NXPE3 genes for COVID-19 with SLE. Bi-directional Mendelian randomization analysis suggested RA is associated with a higher risk of COVID-19 hospitalization, and COVID-19 is not related to RA or SLE. Our novel findings improved the understanding of the common genetic aetiology shared by COVID-19, RA and SLE, and suggested an increased risk of COVID-19 hospitalization in people with higher genetic liability to RA.

Venous thromboembolism (VTE) occurs in up to one third patients with COVID-19. VTE and COVID-19 may share a common genetic architecture, which has not been clarified yet. To fill this gap, we leveraged summary-level genetic data from the latest COVID-19 host genetics consortium and UK Biobank and examined the shared genetic etiology and causal relationship between COVID-19 and VTE. The cross-trait analysis identified 8, 11, and 7 shared loci between VTE and severe COVID-19, COVID-19 hospitalization, SARS-CoV-2 infection respectively, in 13 genes involved in coagulation and immune function and enriched in the lung. Co-localization analysis identified eight shared loci in ABO, ADAMTS13 and FUT2 genes. Bi-direction Mendelian randomization suggested that VTE was associated with higher risks of all COVID-19 related traits, and SARS-CoV-2 infection was associated with higher risk of VTE. Our study provided timely evidence and novel insights into the genetic etiology between COVID-19 and VTE.

APOE genotypes are associated with ischemic heart disease (IHD), several other cardiovascular diseases and dementia. Previous studies have not comprehensively considered all genotypes, especially ε2ε2, nor associations by age and sex, although IHD incidence differs by sex. In the UK Biobank, including 391,992 white British participants, we compared effects of APOE genotypes on IHD and its risk factors. Compared to the ε3ε3 genotype, ε2ε2 was not clearly associated with IHD but was associated with lower plasma apolipoprotein B (apoB). The ε2ε3 genotype conferred lower IHD risk, systolic blood pressure (SBP), pulse pressure and plasma apoB than ε3ε3. ε3ε4 and ε4ε4 conferred higher IHD risk, higher pulse pressure and plasma apoB, but lower glycated haemoglobin (HbA1c) than ε3ε3. The associations by age and sex were fairly similar, except ε2ε2 compared to ε3ε3 was marginally positively associated with IHD in the younger age group and nominally inversely associated with SBP in men. ε3ε4 compared to ε3ε3 was nominally positively associated with SBP in women. APOE genotypes affect IHD risk increasingly from ε2ε3, ε3ε3, ε3ε4 to ε4ε4, with similar patterns for pulse pressure and plasma apoB, but not for diabetes. Associations with blood pressure differed by sex. Greater understanding of products of APOE and their effects might generate targets of intervention.

Background Angiotensin-converting enzyme (ACE) inhibitors and/or in combination with calcium channel blockers (CCBs) are generally recommended as the first-line antihypertensive therapy for people with hypertension and kidney dysfunction. Evidence from large randomized controlled trials comprehensively comparing renal effects of different classes of antihypertensive drugs is lacking. Methods We used a Mendelian randomization study to obtain unconfounded associations of genetic proxies for antihypertensives with kidney function. Specifically, we used published genetic variants in genes regulating target proteins of these drugs and then applied to a meta-analysis of the largest available genome-wide association studies of kidney function (estimated glomerular filtration rate (eGFR), urine albumin-to-creatinine ratio (UACR), and albuminuria). Inverse variance weighting was used as the main analysis and to combine estimates from different sources. Results Genetically predicted ACE inhibition was associated with higher eGFR (effect size 0.06, 95% confidence interval (CI) 0.008, 0.11), while genetic proxies for beta-blockers were associated with lower eGFR (− 0.02, 95% CI − 0.04, − 0.004) when meta-analyzing the UK Biobank and CKDGen. Genetic proxies for CCBs were associated with lower UACR (− 0.15, 95% CI − 0.28, − 0.02) and lower risk of albuminuria (odds ratio 0.58, 95% CI 0.37, 0.90) in CKDGen. The associations were robust to using different analysis methods and different genetic instruments. Conclusions Our findings suggest the reno-protective associations of genetically proxied ACE inhibitors and CCBs, while genetic proxies for beta-blockers may be related to lower eGFR. Understanding the underlying mechanisms would be valuable, with implications for drug development and repositioning of treatments for kidney disease.

BACKGROUND: Kidney function declines faster in men. Testosterone levels may mediate the sex disparity. Correspondingly, levels of sex hormone binding globulin (SHBG), which modulates sex hormones, might also be relevant to the lower kidney function in men. The sex-specific role of SHBG is unclear. METHODS: A sex-specific, Mendelian randomization (MR) study provided unconfounded estimates of SHBG levels among the United Kingdom Biobank population. Univariable MR applied 357 single nucleotide polymorphisms (SNPs) in men and 359 SNPs in women. These published SNPs strongly (P

Aim Angiotensin-converting enzyme 2 (ACE 2) is the binding domain for severe acute respiratory syndrome coronavirus (SARS-CoV) and SARSCoV-2. Some antihypertensive drugs affect ACE2 expression or activity (ACE inhibitors and angiotensin II receptor blockers [ARBs]), suggesting use of other hypertensives might be preferable, such as calcium channel blockers (CCBs). Given the limited evidence, the International Society of Hypertension does not support such a policy. Methods We used a Mendelian randomization study to obtain unconfounded associations of antihypertensives, instrumented by published genetic variants in genes regulating target proteins of these drugs, with immune (lymphocyte and neutrophil percentage) and inflammatory (tumour necrosis factor alpha [TNF-α]) markers in the largest available genome-wide association studies. Results Genetically predicted effects of ACE inhibitors increased lymphocyte percentage (0.78, 95% confidence interval [CI] 0.35, 1.22), decreased neutrophil percentage (-0.64, 95% CI -1.09, -0.20) and possibly lowered TNF-α (-4.92, 95% CI -8.50, -1.33). CCBs showed a similar pattern for immune function (lymphocyte percentage 0.21, 95% CI 0.05 to 0.36; neutrophil percentage -0.23, 95% CI -0.39 to -0.08) but had no effect on TNF-α, as did potassium-sparing diuretics and aldosterone antagonists, and vasodilator antihypertensives. ARBs and other classes of hypertensives had no effect on immune function or TNF-α. Conclusion Varying effects of different classes of antihypertensives on immune and inflammatory markers do not suggest antihypertensive use based on their role in ACE2 expression, but instead suggest investigation of the role of antihypertensives in immune function and inflammation might reveal important information that could optimize their use in SARSCoV-2.

Reasons for the sexual disparity in chronic kidney disease (CKD) are unclear. To provide insight we contextualised these differences within evolutionary biology, and explored sex-specific effects of insulin resistance because it may have sex-specific effects on the reproductive axis. Impaired kidney function may also cause insulin resistance. We assessed these possibilities using bi-directional, sex-specific, two-sample Mendelian randomisation (MR). Given that fasting insulin, fasting glucose and HbA1c are related, we used MR-Bayesian model averaging (MR-BMA) to identify the best-fitting model and most influential exposure. Genetic associations with glycaemic traits were obtained from genome-wide association studies (GWAS) in Europeans without diabetes (n = 108,557 for fasting insulin, as a proxy for insulin resistance, and for fasting glucose, n = 123,665 for HbA1c in the Meta-Analyses of Glucose and Insulin-related traits Consortium [MAGIC]), and applied to GWAS of 480,698 Europeans for overall associations with CKD (cases n = 41,395) and eGFR. We also used sex-specific individual information in white British (179,917 men, 6016 CKD cases; 212,079 women, 5958 CKD cases) from the UK Biobank. Univariable or multivariable MR was used to assess the role of glycaemic trait(s) selected by MR-BMA in CKD and kidney function. Genetic variants predicting eGFR were used to assess the role of kidney function in the most influential exposure(s). Fasting insulin was selected as the most likely exposure by both overall and sex-specific MR-BMA. It increased CKD in men (OR 7.23 per pmol/l higher fasting insulin [95% CI 2.46, 21.2]) but not in women (OR 1.05 [95% CI 0.21, 5.21]), and reduced eGFR in men (−0.04 [95% CI −0.07, −0.01]) but not in women (0.01 [95% CI −0.02, 0.03]). Genetically predicted eGFR was unrelated to fasting insulin. Genetically predicted fasting insulin was sex-specifically associated with CKD and unhealthier kidney function but was not affected by kidney function.

Background and Purpose: Experimental studies showed vitamin D (Vit-D) could promote vascular regeneration and repair. Prior randomized studies had focused mainly on primary prevention. Whether Vit-D protects against ischemic stroke and myocardial infarction recurrence among subjects with prior ischemic insults was unknown. Here, we dissected through Mendelian randomization any effect of Vit-D on the secondary prevention of recurrent ischemic stroke and myocardial infarction. Methods: Based on a genetic risk score for Vit-D constructed from a derivation cohort sample (n=5331, 45% Vit-D deficient, 89% genotyped) via high-throughput exome-chip screening of 12 prior genome-wide association study–identified genetic variants of Vit-D mechanistic pathways ( rs2060793 , rs4588 , and rs7041 ; F statistic, 73; P Results: In the ischemic disease subsample, 11.1% (n=49/441) had developed recurrent ischemic stroke or MI and 13.3% (n=58/441) had developed recurrent or de novo ischemic stroke/MI. Kaplan-Meier analyses showed that genetic risk score predicted improved event-free survival from recurrent ischemic stroke or MI (log-rank, 13.0; P =0.001). Cox regression revealed that genetic risk score independently predicted reduced risk of recurrent ischemic stroke or MI combined (hazards ratio, 0.62 [95% CI, 0.48–0.81]; P Conclusions: Genetically predicted lowering in Vit-D level is causal for the recurrence of ischemic vascular events in persons with prior ischemic stroke or MI.

Life expectancy in the developed West is currently stagnated and remains shorter in men than women. Well-established evolutionary biology theory suggests lifespan trades-off against reproductive success, possibly sex-specifically. We examined whether a key driver of reproductive success, testosterone, affected survival using a Mendelian randomization longevity study in the UK Biobank to obtain unbiased estimates, along with control exposures. We applied published genetic instruments for testosterone to obtain inverse variance weighted estimates of associations with survival to (i.e., age at) recruitment, in 167,020 men and 194,174 women. We similarly obtained estimates for a positive control (smoking initiation), and a negative control (absorbate), a marker of vitamin C metabolism. Testosterone was associated with poorer survival (0.10 years younger at recruitment per effect size of testosterone, 95% confidence interval (CI) 0.004 to 0.20). As expected, smoking initiation was also associated with poorer survival (0.37 years younger, 95% CI 0.25 to 0.50), but not absorbate (0.01 years younger, 95% CI − 0.09 to 0.11). Several aspects of a healthy lifestyle (low animal fat diet) and several widely used medications (statins, metformin, dexamethasone and possibly aspirin) may modulate testosterone. Explicitly designing interventions sex-specifically based on these insights might help address stagnating life expectancy and sexual disparities.

Background Two-sample Mendelian randomization (MR) allows the use of freely accessible summary association results from genome-wide association studies (GWAS) to estimate causal effects of modifiable exposures on outcomes. Some GWAS adjust for heritable covariables in an attempt to estimate direct effects of genetic variants on the trait of interest. One, both or neither of the exposure GWAS and outcome GWAS may have been adjusted for covariables. Methods We performed a simulation study comprising different scenarios that could motivate covariable adjustment in a GWAS and analysed real data to assess the influence of using covariable-adjusted summary association results in two-sample MR. Results In the absence of residual confounding between exposure and covariable, between exposure and outcome, and between covariable and outcome, using covariable-adjusted summary associations for two-sample MR eliminated bias due to horizontal pleiotropy. However, covariable adjustment led to bias in the presence of residual confounding (especially between the covariable and the outcome), even in the absence of horizontal pleiotropy (when the genetic variants would be valid instruments without covariable adjustment). In an analysis using real data from the Genetic Investigation of ANthropometric Traits (GIANT) consortium and UK Biobank, the causal effect estimate of waist circumference on blood pressure changed direction upon adjustment of waist circumference for body mass index. Conclusions Our findings indicate that using covariable-adjusted summary associations in MR should generally be avoided. When that is not possible, careful consideration of the causal relationships underlying the data (including potentially unmeasured confounders) is required to direct sensitivity analyses and interpret results with appropriate caution.

BACKGROUND Evolutionary biology suggests reproduction trades off against longevity. Genetic selection in favor of fertility and ischemic heart disease (IHD) exists in humans. Observationally, soy protects against IHD. Soy amino acids, glutamate and aspartate, may lower androgens. No large randomized controlled trials testing their health effects exist. OBJECTIVE Using Mendelian randomization, we assessed how genetically predicted glutamate and aspartate affected IHD, blood pressure, and diabetes. METHODS A separate sample instrumental variable analysis with genetic instruments was used to obtain unconfounded estimates using genetic variants strongly (P

Bromodomain and extra-terminal (BET) inhibitors, acting via epigenetic mechanisms, have been developed recently as potential new treatments for cancer, including prostate cancer, and inflammatory conditions. Some BET inhibitors, such as RVX-208, also raise high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A-1 levels. A recent meta-analysis of three small trials (n = 798) found that RVX-208 protected against major adverse cardiovascular events (MACE), raising the question as to whether this protective effect was an artefact, a chance finding, or mediated by HDL-C, anti-inflammatory pathways, or other factors. Notably, the effect of RVX-208 on MACE was largely driven by revascularizations, but fewer interventions in the treatment arm could have arisen accidently from favorable effects of RVX-208 on HDL-C and C-reactive protein influencing decisions about patient care. A larger (n = 2400) trial of RVX-208, BETonMACE (NCT02586155), with a more restricted definition of MACE, excluding hospitalizations, will shortly provide clarity. A successful BETonMACE trial would raise the question as to whether RVX-208 operates via lipids, inflammation, or other means, because several previous HDL-C modulators and anti-inflammatories have not provided effective means of treating cardiovascular disease and reducing overall mortality. Re-conceptualizing cardiovascular disease within the well-established evolutionary biology theory that growth and specifically reproduction trade-off against longevity might provide a more comprehensive explanation. Drivers of the gonadotropic axis, particularly androgens, suppress both HDL-C and the immune system while promoting ischemic heart disease and stroke. As such, any effects of RVX-208 on cardiovascular disease might be the result of reducing androgens, of which higher HDL-C and reduced inflammation are biomarkers. Notably, several other effective treatments for cardiovascular disease, such as statins and spironolactone, are known anti-androgens. Results of the BETonMACE trial, and corresponding insight about the mechanism of BET inhibitors in cardiovascular disease, are eagerly awaited.

Background: Ischemic heart disease (IHD) is a leading contributor to global burden of disease. Men are more vulnerable to IHD than women, which could be partly due to sex hormones. Sex hormone binding globulin (SHBG) which lowers circulating testosterone might protect men against IHD. SHBG may also affect IHD independent of testosterone, which has not previously been examined. Methods: To assess the sex-specific role of SHBG in IHD, in univariable Mendelian randomization (MR), we used sex-specific, genome-wide significant genetic variants (343 for men and 328 for women) to predict SHBG, and examined their association with IHD (25,409 cases in men and 12,511 cases in women) in the UK Biobank. We also replicated using genetic instruments from Japanese men and applied to Biobank Japan. To assess the role of SHGB independent of testosterone in men, we used multivariable MR controlling for testosterone, additionally including 125 SNPs for free testosterone. Findings: Genetically predicted SHBG was associated with lower IHD risk in men (odds ratio (OR) 0.77 per standard deviation, 95% confidence interval (CI) 0.69 to 0.87), but not in women. The estimates were robust to different genetic instruments and similar in Japanese. The inverse association remained after controlling for testosterone in men (OR 0.78, 95% CI 0.70 to 0.87). Interpretation: SHBG might lower the risk of IHD in men, with a role independent of testosterone. Exploring intervention strategies that increase SHBG and understanding the underlying pathways is important for targeting IHD treatments to take account of sex disparity. Funding Information: None. Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: This research has been conducted using the UK Biobank Resource under Application number 42468. No original data were collected for the MR study. Ethical approval for each of the studies included in the investigation can be found in the original publications (including informed consent from each participant). The UK Biobank has already received ethical approval from the Research Ethics Committee and participants provided written informed consent. The analysis of other publicly available summary statistics does not require additional ethical approval.

Background: Mendelian randomization (MR) provides unconfounded estimates. MR is open to selection bias when the underlying sample is selected on surviving to recruitment on the genetically instrumented exposure and competing risk of the outcome. Few methods to address this bias exist.Methods: We show that this selection bias can sometimes be addressed by adjusting for common causes of survival and outcome. We use multivariable MR to obtain a corrected MR estimate for statins on stroke. Statins affect survival, and stroke typically occurs later in life than ischemic heart disease (IHD), making estimates for stroke open to bias from competing risk.Results: In univariable MR in the UK Biobank, genetically instrumented statins did not protect against stroke [odds ratio (OR) 1.33, 95% confidence interval (CI) 0.80–2.20] but did in multivariable MR (OR 0.81, 95% CI 0.68–0.98) adjusted for major causes of survival and stroke [blood pressure, body mass index (BMI), and smoking initiation] with a multivariable Q-statistic indicating absence of selection bias. However, the MR estimate for statins on stroke using MEGASTROKE remained positive and the Q statistic indicated pleiotropy.Conclusion: MR studies of harmful exposures on late-onset diseases with shared etiology need to be conceptualized within a mechanistic understanding so as to identify any potential bias due to survival to recruitment on both genetically instrumented exposure and competing risk of the outcome, which may then be investigated using multivariable MR or estimated analytically and results interpreted accordingly.

Background Kidney dysfunction occurs in severe COVID-19, and is a predictor of COVID-19 mortality. Whether kidney dysfunction causes severe COVID-19, and hence is a target of intervention, or whether it is a symptom, is unclear because conventional observational studies are open to confounding. To obtain unconfounded estimates, we used Mendelian randomization to examine the role of kidney function in severe COVID-19. Methods We used genome-wide significant, uncorrelated genetic variants to predict kidney function, in terms of estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (UACR), and then assessed whether people with genetically instrumented higher eGFR or lower UACR, an indication of better kidney function, had a lower risk of severe COVID-19 (8779 cases, 1,001,875 controls), using the largest available cohorts with extensive genotyping. For comprehensiveness, we also examined their role in COVID-19 hospitalization (24,274 cases, 2,061,529 controls) and all COVID-19 (1,12,612 cases, 2,474,079 controls). Results Genetically instrumented higher eGFR was associated with lower risk of severe COVID-19 (odds ratio (OR) 0.90, 95% confidence interval (CI) 0.83, 0.98) but not related to COVID-19 hospitalization or infection. Genetically instrumented UACR was not related to COVID-19. Conclusions Kidney function appears to be one of the key targets for severe COVID-19 treatment. Use of available medications to improve kidney function, such as antihypertensives, might be beneficial for COVID-19 treatment, with relevance to drug repositioning.

We examined whether specifically statins, of the major lipid modifiers (statins, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors and ezetimibe) have pleiotropic effects on ischemic heart disease (IHD) via testosterone in men or women. As a validation, we similarly assessed whether a drug that unexpectedly likely increases IHD also operates via testosterone. Using previously published genetic instruments we conducted a sex-specific univariable and multivariable Mendelian randomization study in the UK Biobank, including 179918 men with 25410 IHD cases and 212080 women with 12511 IHD cases. Of these three lipid modifiers, only genetically mimicking the effects of statins in men affected testosterone, which partly mediated effects on IHD. Correspondingly, genetically mimicking effects of anakinra on testosterone and IHD presented a reverse pattern to that for statins. These insights may facilitate the development of new interventions for cardiovascular diseases as well as highlighting the importance of sex-specific explanations, investigations, prevention and treatment.

BackgroundNew means of treating COVID-19 are urgently needed. Genetic validation of drugs can foreshadow trial results, and help prioritize investigations. We assessed whether common drugs, suggested as possible treatments for COVID-19 (tocilizumab, anakinra and statins) with established genetic proxies, are effective in COVID-19. We also included dexamethasone as a positive control exposure because the RECOVERY trial suggested benefit in severe COVID-19.MethodsWe assessed, using Mendelian randomization, whether genetic proxies of tocilizumab, anakinra, statins and dexamethasone use affected risk of very severe (cases=536, non-cases=329391) or hospitalized (cases=3199, non-cases=897488) COVID-19 using a recent genome-wide association study.ResultsUsing rs2228145 (IL6R) to proxy effects of tocilizumab use, no association with very severe COVID-19 was found, but possibly an inverse association with hospitalized COVID-19 (odds ratio (OR) 0.83 per standardized effect of higher soluble interleukin-6r, 95% confidence interval 0.67 to 1.02). Using rs12916 (HMGCR) to proxy effects of statins use, an inverse association with very severe COVID-19 was found (OR 0.30 per standardized effect, 95% CI 0.10 to 0.89). Using rs6743376 and rs1542176 to proxy effects of anakinra use, no associations with COVID-19 were found. Dexamethasone, instrumented by cortisol, was possibly inversely associated with very severe COVID-19 (OR 0.20 per standardized effect 95% CI 0.04 to 1.04).ConclusionOur study provides some genetic validation for the use of both tocilizumab and statins in COVID-19, but not anakinra, whilst being consistent with the findings from the RECOVERY trial about dexamethasone. Investigation of the underlying mechanisms might facilitate re-purposing and development of effective treatments.

Background Chronic kidney disease (CKD) has an apparent sex disparity, with a more rapid progress in men than in women. Whether the well-established sex-specific evolutionary biology trade-off between reproduction and longevity might inform CKD has not previously been considered. Relevant evidence from randomized controlled trials (RCTs) is not available. Methods We used a bi-directional Mendelian randomization study to obtain unconfounded estimates using the UK Biobank. Single nucleotide polymorphisms (SNPs) that strongly (p value −8) predicted testosterone in a sex-specific manner were applied to 179,916 white British men (6016 CKD cases) and 212,079 white British women (5958 CKD cases) to obtain sex-specific associations with CKD, albuminuria, and estimated glomerular filtration rate (eGFR). We also used multivariable MR to control for sex hormone binding globulin (SHBG). For validation, we similarly examined their role in hemoglobin and high-density lipoprotein cholesterol (HDL-c). We also assessed the role of kidney function in serum testosterone, by applying eGFR-related SNPs to testosterone in the UK Biobank. Results Genetically predicted testosterone was associated with CKD in men (odds ratio (OR) for bioavailable testosterone 1.17 per standard deviation, 95% confidence interval (CI) 1.03 to 1.33) based on 125 SNPs but not in women (OR 1.02, 95% CI 0.92 to 1.14 for total testosterone) based on 254 SNPs. Multivariable MR allowing for SHBG showed consistent patterns. Genetically predicted bioavailable testosterone in men and women and genetically predicted total testosterone in women increased hemoglobin and lowered HDL-c, as seen in RCTs. Genetically predicted eGFR was not related to serum testosterone in men or in women. Conclusions Genetically predicted testosterone was associated with CKD and worse kidney function in men, whilst not affected by kidney function. Identifying drivers of testosterone and the underlying pathways could provide new insights into CKD prevention and treatment.

Earlier age of puberty has detrimental consequences for many aspects of health. Here, for the first time, we assessed the association of earlier puberty with sleep duration observationally and with validation using Mendelian Randomization. In the “Children of 1997” birth cohort (n = 8,327), we used adjusted multivariable logistic regression to assess the associations of each clinically assessed marker of earlier puberty with self-report sleep duration in adolescence. Using two-sample MR, we assessed the effect of earlier puberty timing based on 203 single nucleotide polymorphisms applied to genome wide association studies of sleep duration in adults (n = 335,410). In “Children of 1997”, cross-sectionally, older age of menarche was associated with longer (9+ hours) sleep duration [odds ratio (OR) 1.11, 95% confidence interval (CI) 1.01 to 1.21] at 13.5 years. The other earlier puberty markers were unrelated to sleep duration. Using inverse variance weighting, later of age at menarche increased adult sleep duration [0.020 per category, 95% CI 0.006 to 0.034]. This study demonstrated a causal effect of age at menarche on adult sleep duration, since age of menarche also affects obesity, our novel finding may be relevant to the observed relation of sleep duration with obesity and poor health.

ObjectivesStatins appear to have pleiotropic effects. We examined whether specifically statins, of the major lipid modifiers, operate on ischemic heart disease (IHD) via testosterone. As a validation, we assessed whether a drug that unexpectedly likely increases IHD also operates via testosterone.DesignA sex-specific univariable and multivariable Mendelian randomization studySettingA large, population-based cohort study recruited in the UK from 2006-10, the UK BiobankParticipants179918 men with 25410 IHD cases and 212080 women with 12511 IHD casesMain Outcome measuresTestosterone and IHDResultsOf the three lipid modulations considered, statins, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors and ezetimibe, only genetically predicted statin use in men affected testosterone (−0.15 effect size testosterone per effect size lower (of low-density lipoprotein cholesterol), 95% confidence interval (CI) −0.23 to −0.06). The genetically predicted effect of statin use on IHD in specifically men was partially mediated by testosterone (odds ratio (OR) 0.55 per effect size lower (low-density lipoprotein cholesterol), 95% CI 0.38 to 0.79, compared to OR 0.73, 95% CI 0.46 to 1.11 after allowing for testosterone). The estimate for the effect of genetically predicted statin use, independent of testosterone, was very similar in women, giving overall meta-analyzed OR 0.72, 95% CI 0.57 to 0.90 per effect size lower of low-density lipoprotein cholesterol. The genetically predicted effect of anakinra use also affected testosterone (0.022 per effect size (of IL-1Ra), 95% CI 0.01 to 0.04), and increased IHD in men.ConclusionsStatins may partially operate via testosterone in men, which may contribute to sex-specific pleiotropic effects. Anakinra operating by testosterone may also explain its unexpected effects. Our findings could facilitate the development of new interventions for cardiovascular diseases as well as highlighting the importance of sex-specific investigations and possibly treatments.Section 1: What is already known on this topicStatins appear to have pleiotropic effects on cardiovascular disease. Whether such effects exist and why they should occur is unclear, but could be highly relevant to the prevention and treatment of the leading cause of death.Section 2: What this study addsOur study shows that statins have similar protective effects on ischemic heart disease via low-density lipoprotein cholesterol in men and women, but unlike other major lipid modifiers statins have an additional effect specific to men via testosterone, while any harms of anakinra in men may operate by a similar mechanism. Our findings highlighting the possibility of sex-specific causes of cardiovascular disease and the need for sex-specific investigations, prevention and treatment.

Reasons for the sexual disparity in chronic kidney disease (CKD) are unclear. To provide insight we contextualised these differences within evolutionary biology, and explored sex-specific effects of insulin resistance because it may have sex-specific effects on the reproductive axis. Impaired kidney function may also cause insulin resistance. We assessed these possibilities using bi-directional, sex-specific, two-sample Mendelian randomisation (MR).Given that fasting insulin, fasting glucose and HbAFasting insulin was selected as the most likely exposure by both overall and sex-specific MR-BMA. It increased CKD in men (OR 7.23 per pmol/l higher fasting insulin [95% CI 2.46, 21.2]) but not in women (OR 1.05 [95% CI 0.21, 5.21]), and reduced eGFR in men (-0.04 [95% CI -0.07, -0.01]) but not in women (0.01 [95% CI -0.02, 0.03]). Genetically predicted eGFR was unrelated to fasting insulin.Genetically predicted fasting insulin was sex-specifically associated with CKD and unhealthier kidney function but was not affected by kidney function. Graphical abstract.

Background Development of pharmacological treatments to mitigate ischemic heart disease (IHD) has encompassed disappointing results and expensive failures, which has discouraged investment in new approaches to prevention and control. New treatments are most likely to be successful if they act on genetically validated targets. We assessed whether existing pharmacological treatments for IHD reduction are acting on genetically validated targets and whether all such targets for IHD are currently being exploited. Methods Genes associated with IHD were obtained from the loci of single nucleotide polymorphisms reported in either of two recent genome wide association studies supplemented by a gene-based analysis (accounting for linkage disequilibrium) of CARDIoGRAMplusC4D 1000 Genomes, a large IHD case (n = 60,801)-control (n = 123,504) study. Treatments targeting the products of these IHD genes and genes with products targeted by current IHD treatments were obtained from Kyoto Encyclopedia of Genes and Genomes and Drugbank. Cohen's kappa was used to assess agreement. Results We identified 173 autosomal genes associated with IHD and 236 autosomal genes with products targeted by current IHD treatments, only 8 genes (PCSK9, EDNRA, PLG, LPL, CXCL12, LRP1, CETP and ADORA2A) overlapped, i.e. were both associated with IHD and had products targeted by current IHD treatments. The Cohen's kappa was 0.03. Interventions related to another 29 IHD genes exist, including dietary factors, environmental exposures and existing treatments for other indications. Conclusions Closer alignment of IHD treatments with genetically validated physiological targets may represent a major opportunity for combating a leading cause of global morbidity and mortality through repurposing existing interventions., Highlights • Pharmacological treatments for ischemic heart disease (IHD) target

Autoimmune diseases are a major challenge for global health. From an evolutionary biology perspective, reproduction, particularly androgens, trades off against immune activity.1 Correspondingly, trials suggest androgens improve rheumatoid arthritis (RA).2 3 As such, dietary factors promoting reproduction might prevent or treat autoimmune disorders. Linoleic acid (LA) is a major n−6 polyunsaturated fatty acid (PUFA) in widely used polyunsaturated vegetable oils, such as sunflower, corn, soybean and cottonseed oil. In animal experiments, LA stimulates the synthesis of testosterone.4 Observationally, endogenous LA is inversely associated with RA5 and systemic lupus erythematosus (SLE),6 but these findings have not been confirmed in randomised controlled trials. Comparing autoimmune disorders according to naturally occurring LA-related genetic variants, that is, Mendelian randomisation (MR), provides a means of obtaining unconfounded estimates of causal effects. We obtained strong, independent genetic predictors of LA using (1) the three most significant uncorrelated single-nucleotide polymorphisms (SNPs) and (2) …

Insulin drives growth and reproduction which trade-off against longevity. Genetically predicted insulin, i.e., insulin proxied by genetic variants, is positively associated with ischemic heart disease, but sex differences are unclear, despite different disease rates and reproductive strategies by sex. We used Mendelian randomization in 392,010 white British from the UK Biobank to assess the sex-specific role of genetically predicted insulin in myocardial infarction (MI) (14,442 cases, 77% men), angina (21,939 cases, 65% men) and heart failure (5537 cases, 71% men). Genetically predicted insulin was associated with MI (odds ratio (OR) 4.27 per pmol/L higher insulin, 95% confidence interval (CI) 1.60 to 11.3) and angina (OR 2.93, 1.27 to 6.73) in men, but not women (MI OR 0.80, 95% CI 0.23 to 2.84, angina OR 1.10, 95% CI 0.38 to 3.18). Patterns were similar for insulin resistance and heart failure. Mitigating the effects of insulin might address sexual disparities in health., Jie Zhao, Shan Luo, and C. Mary Schooling report a Mendelian randomization study of the role of genetically-predicted insulin on myocardial infarction (MI), angina, and heart failure in the UK Biobank. They find an association of insulin with MI and angina in men but not women, which may contribute to the different rates of cardiovascular diseases in men and women.

BackgroundMendelian randomization (MR) provides unconfounded estimates. MR is open to selection bias particularly when the underlying sample is selected on surviving the genetically instrumented exposure and other conditions that share etiology with the outcome (competing risk before recruitment). Few methods to address this bias exist.MethodsWe use directed acyclic graphs to show this selection bias can be addressed by adjusting for common causes of survival and outcome. We use multivariable MR to obtain a corrected MR estimate, specifically, the effect of statin use on ischemic stroke, because statins affect survival and stroke typically occurs later in life than ischemic heart disease so is open to competing risk.ResultsIn univariable MR the genetically instrumented effect of statin use on ischemic stroke was in a harmful direction in MEGASTROKE and the UK Biobank (odds ratio (OR) 1.33, 95% confidence interval (CI) 0.80 to 2.20). In multivariable MR adjusted for major causes of survival and ischemic stroke, (blood pressure, body mass index and smoking initiation) the effect of statin use on stroke in the UK Biobank was as expected (OR 0.81, 95% CI 0.68 to 0.98) with a Q-statistic indicating absence of genetic pleiotropy or selection bias, but not in MEGASTROKE.ConclusionMR studies concerning late onset chronic conditions with shared etiology based on samples recruited in later life need to be conceptualized within a mechanistic understanding, so as to any identify potential bias due to competing risk before recruitment, and to inform the analysis and interpretation.

Background The role of n-6 polyunsaturated fatty acids (PUFAs) in ischemic heart disease (IHD) is controversial, and dietary guidelines vary. Observationally, lower saturated fat intake and higher intake of vegetable oils rich in linoleic acid (LA), the main n-6 PUFA, is associated with lower IHD and diabetes; however, randomized controlled trials have not fully corroborated these benefits. We assessed how genetically predicted LA affected IHD and its risk factors, including diabetes, lipids, and blood pressure. We also assessed the role of LA in reticulocyte count, the red blood cell precursor, which has recently been identified as a possible causal factor in IHD. Methods Two-sample instrumental variable analysis with genetic instruments, i.e., Mendelian randomization, was used to obtain unconfounded estimates using genetic variants strongly (p value

Background Asthma is a common respiratory disease, possibly caused by autoimmunity. Linoleic acid (LA), the main n-6 (ω-6) PUFA from widely used vegetable oils, is thought to suppress immune responses that might have benefits for asthma. However, this question has not been examined in randomized controlled trials. Objectives To obtain unconfounded estimates, we assessed how genetically predicted LA affected asthma using 2-sample Mendelian randomization. We also examined its role in white blood cell traits (eosinophil, neutrophil, and low monocyte counts) identified as potential causal factors in asthma. Methods We used 18 uncorrelated, genome-wide significant genetic variants to predict LA, which we applied to a large genetic case (n = 19,954)-control (n = 107,715) study of asthma, to the UK Biobank (408,961 people of European ancestry with 26,332 asthma cases), and for white blood cell traits to the UK Biobank. We also repeated the analysis on asthma using 29 replicated, functionally relevant genetic variants. In addition, we examined the role of asthma in LA to assess reverse causality. Results Genetically predicted LA was associated with lower risk of asthma (OR: 0.89 per SD increase in LA; 95% CI: 0.85, 0.93), with no association of asthma with LA. Genetically predicted LA was associated with lower eosinophil count (-0.03; 95% CI: -0.061, -0.004) and lower neutrophil count (-0.04; 95% CI: -0.057, -0.023). These estimates were robust to different selections of genetic variants and sensitivity analyses. Conclusions LA might protect against asthma possibly via white blood cell traits, with relevance to the identification of effective new interventions for asthma.