Interaction between the Gly460Trp α-adducin gene variant and diuretics on the risk of myocardial infarction

Risk of myocardial infarction associated with non‐steroidal anti‐inflammatory drugs: Impact of additional confounding control for variables collected from self‐reported data

What is known and objective

Important risk factors and over‐the‐counter (OTC) dispensing of non‐steroidal anti‐inflammatory drugs (NSAIDs) are often not routinely recorded in electronic health records. This study aimed to assess the impact of patient's reports on these factors on the risk of acute myocardial infarction (AMI) for NSAID use.

Methods

A nested case‐control study was conducted among adults in the Utrecht Cardiovascular Pharmacogenetics study. Cases were patients with a first diagnosis of AMI as a hospital discharge diagnosis and controls were those without AMI. NSAID exposure was either current use of selective COX‐2 inhibitors or conventional NSAIDs. Information was collected from The Dutch PHARMO Database Network (pharmacy records of drug dispensing linked to hospitalization records) and the patient's questionnaire (lifestyle factors, body mass index and history of cardiovascular diseases). Unconditional logistic regression analysis was used to calculate odds ratios (ORs) and to control for confounding factors.

Results

We identified 970 AMI cases and 2974 controls. Among cases, 11 (1.1%) and 185 (19.1%) were exposed to selective COX‐2 inhibitors and conventional NSAIDs, respectively. Compared to non‐use, none of these drug classes were associated with an increased risk of AMI (adjusted OR 1.07, 95% CI: 0.52‐2.18 and 0.93, 95% CI: 0.77‐1.12, respectively). Additional adjustment for potential confounders from patient's reports did not change the risk estimates (adjusted OR 1.08, 95% CI: 0.53‐2.22 and 0.89, 95% CI: 0.73‐1.09, respectively).

What is new and conclusion

Additional confounding control for variables from self‐reported data or considering self‐reported OTC NSAID use did not change the risk estimates for the association between NSAIDs and AMI.

Risk of acute myocardial infarction after discontinuation of antihypertensive agents: a case-control study

We performed a nested case-control study in a cohort of antihypertensive drug users to assess the association between discontinuation of different antihypertensive agents and the risk of acute myocardial infarction (AMI). Cases and controls were drawn from the Utrecht Cardiovascular Pharmacogenetics database. Patients who were hospitalised for their first AMI were considered cases and controls were not hospitalised for AMI. Antihypertensive users were defined as current users if the index date (date of AMI) fell within the prescribed duration or as discontinuers if this date fell outside the prescribed duration. According to the recency of discontinuation, discontinuers were divided into the following: recent discontinuers (⩽90 days), intermediate-term discontinuers (91-180 days) and long-term discontinuers (>180 days). We found that the risk of AMI was significantly increased in discontinuers, regardless of time since discontinuation, of beta-blockers (adjusted odds ratio (OR) 1.54; 95% confidence interval (CI; 1.25-1.91), P-value<0.0005), calcium channel blockers (CCBs; adjusted OR 2.25; 95% CI (1.53-3.30), P-value<0.0005) and diuretics (adjusted OR 1.76; 95% CI (1.24-2.48), P-value=0.002) compared to current users of these drugs. Moreover, the risk of AMI was significantly increased in long-term discontinuers (beta-blockers, CCBs, angiotensin-converting enzyme inhibitors and diuretics) and intermediate-term discontinuers (beta-blockers and CCBs) versus current users of these drugs. There was no difference in AMI risk between recent discontinuers of antihypertensive drugs versus current users of these drugs. In conclusion, discontinuation of antihypertensive drugs increases the risk of AMI after >90 days of discontinuation. This further underlines the importance of persistence to antihypertensive drug therapy to reduce the risk of AMI in patients with hypertension.

Patterns of antiplatelet drug use after a first myocardial infarction during a 10-year period

AIMS

The aims of the present study were to assess antiplatelet drug use patterns after a first myocardial infarction (MI) and to evaluate the determinants of antiplatelet nonpersistence.

METHODS

The present study was conducted in 4690 patients from the Utrecht Cardiovascular Pharmacogenetics cohort with a first MI between 1986 and 2010, who were followed for a maximum of 10 years. Medication use and event diagnosis were obtained from the Dutch PHARMO Record Linkage System. Antiplatelet drug users were classified as persistent users (gap between prescriptions ≤90 days), nonpersistent users (>90-day gap and no refills), and restarters (a new prescription after a >90-day gap). The association between potential determinants and antiplatelet nonpersistence was analysed using Cox regression.

RESULTS

The proportions of persistent users decreased from 84.0% at the 1-year follow-up to 32.8% at 10 years for any antiplatelet drug, and 77.3% to 27.5% for aspirin; and 39.0% to 6.4% for clopidogrel at 6 years. Most nonpersistent users restarted antiplatelet drugs later, leading to 89.3% overall antiplatelet drug users at 10 years after MI. Diabetes (hazard ratio [HR] 0.44; 0.32-0.60), hypertension (HR 0.77; 0.60-0.99), hypercholesterolaemia (HR 0.49; 0.39-0.62) and more recent MI diagnosis period (2003-2007: HR 0.69, 0.61-0.79; 2008-2010: HR 0.38, 0.19-0.77, compared to ≤ 2002 period) lowered the risk of antiplatelet nonpersistence, while vitamin K antagonist (VKA) comedication (HR 18.97; 16.91-21.28) increased this risk.

CONCLUSIONS

A large proportion of patients with a first MI still used antiplatelet drugs after 10 years. The frequent discontinuations during this time frame are expected to reduce the effectiveness of antiplatelet drugs as secondary prevention of cardiovascular diseases. Diabetes, hypertension, hypercholesterolaemia, VKA comedication and MI diagnosis period were determinants of antiplatelet nonpersistence.

Hypertension pharmacogenomics: in search of personalized treatment approaches

Cardiovascular and renal diseases are associated with many risk factors, of which hypertension is one of the most prevalent. Worldwide, blood pressure control is only achieved in ∼50% of those treated for hypertension, despite the availability of a considerable number of antihypertensive drugs from different pharmacological classes. Although many reasons exist for poor blood pressure control, a likely contributor is the inability to predict to which antihypertensive drug an individual is most likely to respond. Hypertension pharmacogenomics and other 'omics' technologies have the potential to identify genetic signals that are predictive of response or adverse outcome to particular drugs, and guide selection of hypertension treatment for a given individual. Continued research in this field will enhance our understanding of how to maximally deploy the various antihypertensive drug classes to optimize blood pressure response at the individual level. This Review summarizes the available literature on the most convincing genetic signals associated with antihypertensive drug responses and adverse cardiovascular outcomes. Future research in this area will be facilitated by enhancing collaboration between research groups through consortia such as the International Consortium for Antihypertensives Pharmacogenomics Studies, with the goal of translating replicated findings into clinical implementation.

No association between CYP3A4*22 and statin effectiveness in reducing the risk for myocardial infarction

AIM

Genetic variation has been shown to influence statin response in terms of lowering LDL cholesterol. The recently discovered CYP3A4*22 allele (defined as rs35599367) has been shown to affect statin-induced LDL cholesterol lowering. Our objective was to investigate whether this polymorphism modifies the risk reduction for myocardial infarction (MI) by statins.

PATIENTS & METHODS

We analyzed the interaction between the *22 minor allele and statin use in the independent Utrecht Cardiovascular Pharmacogenetics study and Rotterdam Study, using logistic and Cox regression models.

RESULTS

In total, 771 MI cases and 6131 controls were included in the analyses. There was no effect of the CYP3A4*22 allelic status in the studies separately, nor when the estimates from both studies were combined (interaction odds ratio: 1.27; 95% CI: 0.73-2.21; p = 0.40 for carriers of the minor T-allele).

CONCLUSION

We found no association of the CYP3A4*22 minor allele (rs35599367) with the effectiveness of statins in reducing MI risk.

Association of polymorphisms in the beta-2 adrenergic receptor gene with fracture risk and bone mineral density

Signaling through the beta-2 adrenergic receptor (B2AR) on the osteoblast influences bone remodeling in rodents. In the B2AR gene, three polymorphisms influence receptor function. We show that these polymorphisms are not associated with fracture risk or bone mineral density in the UCP, Rotterdam Study, and GEFOS cohorts.

INTRODUCTION

Signaling through the beta-2 adrenergic receptor (B2AR) on the osteoblast influences bone remodeling in rodents. In the B2AR gene, three polymorphisms are known to influence receptor function in vitro and in vivo (rs1042713, rs1042714, and rs1800888). We examined the role of these polymorphisms in the B2AR gene on human bone metabolism.

METHODS

We performed nested case-control studies to determine the association of these polymorphisms with fracture risk in the Utrecht Cardiovascular Pharmacogenetics (UCP) cohort and in three cohorts of the Rotterdam Study. We also determined the association of these polymorphisms with bone mineral density (BMD) in the GEFOS Consortium. UCP contains drug-dispensing histories from community pharmacies linked to national registrations of hospital discharges in the Netherlands. The Rotterdam Study is a prospective cohort study investigating demographics and risk factors of chronic diseases. GEFOS is a large international collaboration studying the genetics of osteoporosis. Fractures were defined by ICD-9 codes 800-829 in the UCP cohort (158 cases and 2617 unmatched controls) and by regular X-ray examinations, general practitioner, and hospital records in the Rotterdam Study (2209 cases and 8559 unmatched controls). BMD was measured at the femoral neck and lumbar spine using dual-energy X-ray absorptiometry in GEFOS (N = 32,961).

RESULTS

Meta-analysis of the two nested case-control studies showed pooled odds ratios of 0.98 (0.91-1.05, p = 0.52), 1.04 (0.97-1.12, p = 0.28), and 1.16 (0.83-1.62, p = 0.38) for the associations between rs1042713, rs1042714, and rs1800888 per minor allele and fractures, respectively. There were no significant associations of the polymorphisms and BMD in GEFOS.

CONCLUSION

In conclusion, polymorphisms in the beta-2 adrenergic receptor gene are not associated with fracture risk or BMD.

Polymorphisms, hypertension and thiazide diuretics

It is 10 years since the discovery of the human genome; however, the study of the influence of genetic variants on drug effect - pharmacogenomics - has so far failed to create a major impact on day-to-day prescription practices. In the present article we analyze the main findings in candidate gene variants, gene combinations and whole-genome scans in relation to diuretic treatment. A critical analysis of the main reasons for some contrasting results will be discussed. The hypertension phases, in clinical trials dealing with genes and related pathophysiological mechanisms, may account for these inconsistent findings. The use of previously untreated versus treated patients is addressed. Finally, a positive study with a new genetic molecular strategy is described.

Genetic variability within the cholesterol lowering pathway and the effectiveness of statins in reducing the risk of MI

Genetic variability has been shown to affect statin responsiveness. Participants from the Utrecht Cardiovascular Pharmacogenetics (UCP) studies were enrolled from a population-based registry of pharmacy records linked to hospital discharge records (PHARMO) to investigate tagging SNPs within candidate genes involved in the cholesterol lowering pathway for modification of the effectiveness of statins in reducing the risk of myocardial infarction (MI). Patients who received a prescription for an antihypertensive drug and/or had hypercholesterolemia were selected from the PHARMO database. We designed a nested case-control study in which cases were hospitalized for MI and controls were not. Patients were contacted through their community pharmacies. For this study, only hypercholesterolemic participants were selected. Logistic regression analysis was used to investigate pharmacogenetic interactions. The Heart and Vascular Health Study (HVH) was used to replicate findings from UCP. The study population included 668 cases and 1217 controls. We selected 231 SNPs of which 209 SNPs in 27 genes passed quality control. Ten SNPs in eight genes were found to influence the effectiveness of statins in UCP, of which the most significant interaction was found with SCARB1 rs4765615. Other genes that reached statistical significance (p<0.05) included two SNPs in PCSK9 (rs10888896 and rs505151 (E670G)), two SNPs in ABCG5 (rs4245786 and rs1864815), LIPC rs16940379, ABCA1 rs4149264, PPARG rs2972164, LRP1 rs715948, and SOAT1 rs2493121. None of the total of 5 SNPs that were available for replication in HVH reached statistical significance. In conclusion, ten SNPs were found to modify the effectiveness of statins in reducing the risk of MI in the UCP study. Five were also tested in the HVH study, but no interactions reached statistical significance.

Genome-wide association studies of hypertension: have they been fruitful?

Over the last two decades candidate gene association studies and genome-wide linkage scans have met with little success in characterizing risk variants for hypertension. Several factors could be responsible for the relative lack of success, although our understanding of the genetics has evolved to support the belief that there are multiple common risk variants, which are associated with hypertension with modest effect sizes. Genome-wide association studies (GWAS) have successfully identified risk loci for several complex polygenic disease states. Until recently, the productivity of GWAS with respect to identifying risk loci for hypertension was limited. In this paper we describe the recent success of GWAS of hypertension in identifying over a dozen loci associated with essential hypertension. We will review these findings, and place these results in the context of the future potential of pharmocogenetics of hypertension.

Determinants of DNA yield and purity collected with buccal cell samples

Buccal cells are an important source of DNA in epidemiological studies, but little is known about factors that influence amount and purity of DNA. We assessed these factors in a self-administered buccal cell collection procedure, obtained with three cotton swabs. In 2,451 patients DNA yield and in 1,033 patients DNA purity was assessed. Total DNA yield ranged from 0.08 to 1078.0 μg (median 54.3 μg; mean 82.2 μg ± SD 92.6). The median UV 260:280 ratio, was 1.95. Samples from men yielded significantly more DNA (median 58.7 μg) than those from women (median 44.2 μg). Diuretic drug users had significantly lower purity (median 1.92) compared to other antihypertensive drug users (1.95). One technician obtained significantly lower DNA yields. Older age was associated with lower DNA purity. In conclusion, DNA yield from buccal swabs was higher in men and DNA purity was associated with age and the use of diuretics.