Citations

Abstract Coronary artery disease (CAD) is a leading cause of death, yet its genetic determinants are not fully elucidated. We report a multi-ethnic genome-wide association study of CAD involving nearly a quarter of a million cases, incorporating the largest cohorts to date of Whites, Blacks, and Hispanics from the Million Veteran Program with existing studies including CARDIoGRAMplusC4D, UK Biobank, and Biobank Japan. We verify substantial and nearly equivalent heritability of CAD across multiple ancestral groups, discover 107 novel loci including the first nine on the X-chromosome, identify the first eight genome-wide significant loci among Blacks and Hispanics, and demonstrate that two common haplotypes are largely responsible for the risk stratification at the well-known 9p21 locus in most populations except those of African origin where both haplotypes are virtually absent. We identify 15 loci for angiographically derived burden of coronary atherosclerosis, which robustly overlap with the strongest and earliest loci reported to date for clinical CAD. Phenome-wide association analyses of novel loci and externally validated polygenic risk scores (PRS) augment signals from the insulin resistance cluster of risk factors and consequences, extend previously established pleiotropic associations of loci with traditional risk factors to include smoking and family history, and confirm a substantially reduced transferability of existing PRS to Blacks. Downstream integrative genomic analyses reinforce the critical role of endothelial, fibroblast, and smooth muscle cells within the coronary vessel wall in CAD susceptibility. Our study highlights the value of a multi-ethnic design in efficiently characterizing the genetic architecture of CAD across all human populations.

Background: Abdominal aortic aneurysm (AAA) is an important cause of cardiovascular mortality; however, its genetic determinants remain incompletely defined. In total, 10 previously identified risk loci explain a small fraction of AAA heritability. Methods: We performed a genome-wide association study in the Million Veteran Program testing ≈18 million DNA sequence variants with AAA (7642 cases and 172 172 controls) in veterans of European ancestry with independent replication in up to 4972 cases and 99 858 controls. We then used mendelian randomization to examine the causal effects of blood pressure on AAA. We examined the association of AAA risk variants with aneurysms in the lower extremity, cerebral, and iliac arterial beds, and derived a genome-wide polygenic risk score (PRS) to identify a subset of the population at greater risk for disease. Results: Through a genome-wide association study, we identified 14 novel loci, bringing the total number of known significant AAA loci to 24. In our mendelian randomization analysis, we demonstrate that a genetic increase of 10 mm Hg in diastolic blood pressure (odds ratio, 1.43 [95% CI, 1.24–1.66]; P =1.6×10 −6 ), as opposed to systolic blood pressure (odds ratio, 1.06 [95% CI, 0.97–1.15]; P =0.2), likely has a causal relationship with AAA development. We observed that 19 of 24 AAA risk variants associate with aneurysms in at least 1 other vascular territory. A 29-variant PRS was strongly associated with AAA (odds ratio PRS , 1.26 [95% CI, 1.18–1.36]; P PRS =2.7×10 −11 per SD increase in PRS), independent of family history and smoking risk factors (odds ratio PRS+family history+smoking , 1.24 [95% CI, 1.14–1.35]; P PRS =1.27×10 −6 ). Using this PRS, we identified a subset of the population with AAA prevalence greater than that observed in screening trials informing current guidelines. Conclusions: We identify novel AAA genetic associations with therapeutic implications and identify a subset of the population at significantly increased genetic risk of AAA independent of family history. Our data suggest that extending current screening guidelines to include testing to identify those with high polygenic AAA risk, once the cost of genotyping becomes comparable with that of screening ultrasound, would significantly increase the yield of current screening at reasonable cost.

Background Current treatment guidelines strongly recommend statin therapy for secondary prevention. However, it remains unclear whether patients’ perceptions of cardiovascular risk, beliefs on cholesterol, or the intensity of prescribed statin therapy differs for patients with coronary artery disease ( CAD ) versus cerebrovascular disease (Ce VD ) versus both CAD and Ce VD ( CAD &Ce VD ). Methods and Results The PALM (Patient and Provider Assessment of Lipid Management) registry collected data on statin use, intensity, and core laboratory low‐density lipoprotein cholesterol levels for 3232 secondary prevention patients treated at 133 US clinics. Among individuals with Ce VD only (n=403), CAD only (n=2202), and Ce VD & CAD (n=627), no significant differences were observed in patient‐perceived cardiovascular disease risk, beliefs on cholesterol lowering, or perceived effectiveness and safety of statin therapy. However, patients with Ce VD only were less likely to receive any statin therapy (76.2% versus 86.2%; adjusted odds ratio 0.64, 95% CI 0.45–0.91), or guideline‐recommended statin intensity (34.6% versus 50.4%; adjusted odds ratio 0.60, 95% CI 0.45–0.81) than those with CAD only. Individuals with Ce VD only were also less likely to achieve low‐density lipoprotein cholesterol <100 mg/ dL (59.2% versus 69.7%; adjusted odds ratio 0.79, 95% CI 0.64–0.99) than individuals with CAD alone. There were no significant differences in the use of any statin therapy or guideline‐recommended statin intensity between individuals with CAD &Ce VD and those with CAD only. Conclusions Despite lack of significant differences in patient‐perceived cardiovascular risk or statin beliefs, patients with Ce VD were significantly less likely to receive higher intensity statin or achieve low‐density lipoprotein cholesterol <100 mg/ dL than those with CAD only.

Background: Female patients have historically received less aggressive lipid management than male patients. Contemporary care patterns and the potential causes for these differences are unknown. Methods and Results: Examining the Patient and Provider Assessment of Lipid Management Registry—a nationwide registry of outpatients with or at risk for atherosclerotic cardiovascular disease—we compared the use of statin therapy, guideline-recommended statin dosing, and reasons for undertreatment. We specifically analyzed sex differences in statin treatment and guideline-recommended statin dosing using multivariable logistic regression. Among 5693 participants (43% women) eligible for 2013 American College of Cardiology/American Heart Association Cholesterol Guideline–recommended statin treatment, women were less likely than men to be prescribed any statin therapy (67.0% versus 78.4%; P <0.001) or to receive a statin at the guideline-recommended intensity (36.7% versus 45.2%; P <0.001). Women were more likely to report having previously never been offered statin therapy (18.6% versus 13.5%; P <0.001), declined statin therapy (3.6% versus 2.0%; P <0.001), or discontinued their statin (10.9% versus 6.1%; P <0.001). Women were also less likely than men to believe statins were safe (47.9% versus 55.2%; P <0.001) or effective (68.0% versus 73.2%; P <0.001) and more likely to report discontinuing their statin because of a side effect (7.9% versus 3.6%; P <0.001). Sex differences in both overall and guideline-recommended intensity statin use persisted after adjustment for demographics, socioeconomic factors, clinical characteristics, patient beliefs, and provider characteristics (adjusted odds ratio, 0.70; 95% CI, 0.61–0.81; P <0.001; and odds ratio, 0.82; 95% CI, 0.73–0.92; P <0.01, respectively). Sex differences were consistent across primary and secondary prevention indications for statin treatment. Conclusions: Women eligible for statin therapy were less likely than men to be treated with any statin or guideline-recommended statin intensity. A combination of women being offered statin therapy less frequently, while declining and discontinuing treatment more frequently, accounted for these sex differences in statin use.

Physiological events involved in nociception and pain perception are examined. Substance P could be a primary afferent transmitter of certain nociceptive information. Transmission of this information can be modulated within the spinal cord by intrinsic and descending mechanisms. The intrinsic mechanism involves inhibitory opiate effects within substantia gelatinosa. Centres for descending systems are located in medulla and periaqueductal gray matter. They are activated by exogenous narcotic agonists, and by regional connections. Descending inhibitory pathways are serotonergic and noradrenergic. GABA and glycine are also possibly involved in antinociception. Narcotics have been shown to produce analgesia when administered to the intrathecal or epidural spaces of humans. These routes are still experimental. The place of clinical modification of transmitter system is discussed, but no conclusions or recommendations can be made at this early stage.