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Joel G Ray

Publications and source records attributed to Joel G Ray.

At least 37 records · Page 2Linked to original sources
PubMed2004

Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy.

This article discusses the prevention of venous thromboembolism (VTE) and is part of the Seventh American College of Chest Physicians Conference on Antithrombotic and Thrombolytic Therapy: Evidence-Based Guidelines. Grade 1 recommendations are strong and indicate that the benefits do, or do not, outweigh risks, burden, and costs. Grade 2 suggests that individual patients' values may lead to different choices (for a full understanding of the grading see Guyatt et al, CHEST 2004; 126:179S-187S). Among the key recommendations in this chapter are the following. We recommend against the use of aspirin alone as thromboprophylaxis for any patient group (Grade 1A). For moderate-risk general surgery patients, we recommend prophylaxis with low-dose unfractionated heparin (LDUH) (5,000 U bid) or low-molecular-weight heparin (LMWH) [< or = 3,400 U once daily] (both Grade 1A). For higher risk general surgery patients, we recommend thromboprophylaxis with LDUH (5,000 U tid) or LMWH (> 3,400 U daily) [both Grade 1A]. For high-risk general surgery patients with multiple risk factors, we recommend combining pharmacologic methods (LDUH three times daily or LMWH, > 3,400 U daily) with the use of graduated compression stockings and/or intermittent pneumatic compression devices (Grade 1C+). We recommend that thromboprophylaxis be used in all patients undergoing major gynecologic surgery (Grade 1A) or major, open urologic procedures, and we recommend prophylaxis with LDUH two times or three times daily (Grade 1A). For patients undergoing elective total hip or knee arthroplasty, we recommend one of the following three anticoagulant agents: LMWH, fondaparinux, or adjusted-dose vitamin K antagonist (VKA) [international normalized ratio (INR) target, 2.5; range, 2.0 to 3.0] (all Grade 1A). For patients undergoing hip fracture surgery (HFS), we recommend the routine use of fondaparinux (Grade 1A), LMWH (Grade 1C+), VKA (target INR, 2.5; range, 2.0 to 3.0) [Grade 2B], or LDUH (Grade 1B). We recommend that patients undergoing hip or knee arthroplasty, or HFS receive thromboprophylaxis for at least 10 days (Grade 1A). We recommend that all trauma patients with at least one risk factor for VTE receive thromboprophylaxis (Grade 1A). In acutely ill medical patients who have been admitted to the hospital with congestive heart failure or severe respiratory disease, or who are confined to bed and have one or more additional risk factors, we recommend prophylaxis with LDUH (Grade 1A) or LMWH (Grade 1A). We recommend, on admission to the intensive care unit, all patients be assessed for their risk of VTE. Accordingly, most patients should receive thromboprophylaxis (Grade 1A).

Anticoagulants↗
PubMed2003

Sale of kava extract in some health food stores.

January 2002, Health Canada issued an advisory, followed by a ban in August 2002, on the sale of herbal kava. One month after the advisory, 22 (67%) of 33 health food stores approached were selling kava. Two months after the ban, 17 (57%) of 30 stores continued to sell kava. These findings demonstrate that health food stores may need to be better informed about the sale of restricted natural health products.

Canada↗
PubMed2003

Prevalence of trisomy 21 following folic acid food fortification.

Polymorphisms of maternal genes responsible for normal folate metabolism may be associated with an increased risk of fetal trisomy 21. By January 1998, most of Canada's flour was being fortified with folic acid. We investigated whether the prevalence of antenatally and postnatally detected trisomy 21 changed before and after folic acid food fortification. A total of 218,977 women underwent second trimester maternal serum screening for trisomy 21 in the 48 months before fortification and 117,986 women were screened in the 29 months after fortification. There were 375 identified cases of trisomy 21 before fortification (1.71 per 1,000), compared to 201 cases thereafter (1.70 per 1,000) for a crude prevalence ratio (PR) of 0.99 (95% confidence interval [CI] 0.84-1.18). The associated risk of trisomy 21 did not change after adjustment for mean maternal age (adjusted PR 0.99 [95% CI 0.82-1.19]). Similarly, no significant decline in the monthly prevalence of trisomy 21 was observed using autoregressive integrated moving average time series analysis (P = 0.24). In conclusion, we failed to observe a decline in the occurrence of trisomy 21 following folic acid food fortification.

Adult↗
PubMed2003

Increased blood product use among coronary artery bypass patients prescribed preoperative aspirin and clopidogrel.

BACKGROUND: The administration of antiplatelet drugs before coronary artery bypass graft surgery (CABG) is associated with an increased risk of major hemorrhage and related surgical reexploration. Little is known about the relative effect of combined clopidogrel and aspirin on blood product use around the time of CABG. We evaluated the associated risk between the combined use of aspirin and clopidogrel and the transfusion of blood products perioperatively. METHODS: We retrospectively studied a cohort of 659 individuals who underwent a first CABG, without concomitant valvular or aortic surgery, at a single large Canadian cardiac surgical centre between January 2000 and April 2002. The four study exposure groups were those prescribed aspirin (n = 105), clopidogrel (n = 11), the combination of both (n = 46), or neither drug (n = 497), within 7 days prior to CABG. The primary study outcome was the excessive transfusion of blood products during CABG and up to the second post-operative day, defined as > or = 2 units of packed red blood cells (PRBC), > or = 2 units of fresh frozen plasma, > or = 5 units of cryoprecipitate or > or = 5 units of platelets. Secondary outcomes included the mean number of transfused units of each type of blood product. RESULTS: A greater mean number of units of PRBC were transfused among those who received clopidogrel alone (2.9) or in combination with aspirin (2.4), compared to those on aspirin alone (1.9) or neither antiplatelet drug (1.4) (P = 0.001). A similar trend was seen for the respective mean number of transfused units of platelets (3.6, 3.7, 1.3 and 1.0; P < 0.001) and fresh frozen plasma (2.5, 3.1, 2.3, 1.6; P = 0.01). Compared to non-users, the associated risk of excessive blood product transfusion was highest among recipients of aspirin and clopidogrel together (adjusted OR 2.2, 95% CI 1.1-4.3). No significant association was seen among lone users of aspirin (adjusted OR 1.0, 95% CI 0.6-1.6) or clopidogrel (adjusted OR 0.7, 95% CI 0.2-2.5), compared to non-users. CONCLUSIONS: While combined use of aspirin and clopidogrel shortly before CABG surgery may increase the associated risk of excess transfusion of blood products perioperatively, several study limitations prevent any confident conclusions from being drawn. Beyond challenging these findings, future research might focus on the value of both intraoperative monitoring of platelet function, and the effectiveness of antifibrinolytic agents, at reducing the risk of postoperative bleeding.

Aged↗
PubMed2003

Folic acid food fortification is associated with a decline in neuroblastoma.

BACKGROUND: Neuroblastoma, an embryonic tumor, is the second most common pediatric tumor and is the most prevalent extracranial solid tumor in children. Results of previous studies have suggested that maternal vitamin intake may decrease the risk of several childhood cancers. In January 1997, Canada began fortifying flour with folic acid for the prevention of neural tube defects. The effect of folic acid fortification on the rate of neuroblastoma in offspring is not known. METHODS: We investigated the rates of neuroblastoma (<1 year), acute lymphoblastic leukemia, and hepatoblastoma registered by the Pediatric Oncology Group of Ontario, which captures 95% of all pediatric cancers in Ontario, before and after the introduction of folate fortification. RESULTS: An interventional time series analysis showed that the incidence of neuroblastoma declined from 1.57 cases per 10,000 births before to 0.62 case per 10,000 births after folic acid fortification (P <.0001). The crude incidence rate ratio (0.40; 95% confidence interval, 0.25-0.64) remained significant after adjustment for both age and disease stage at diagnosis (adjusted incidence rate ratio, 0.38; 95% confidence interval, 0.23-0.62). In contrast, there was no significant change in the rate of infant acute lymphoblastic leukemia (incidence rate ratio, 0.97; 95% confidence interval, 0.41-2.27) or hepatoblastoma (incidence rate ratio, 0.81; 95% confidence interval, 0.35-1.89). CONCLUSIONS: Folic acid fortification was associated with a 60% reduction in neuroblastoma but was not associated with any change in the rate of infant acute lymphoblastic leukemia or hepatoblastoma. Further investigation is needed into the role of metabolism in the formation and prevention of neuroblastoma and other embryonically determined cancers.

Canada↗
PubMed2003

Association between folic acid food fortification and congenital orofacial clefts.

By January 1998, most of Canada's cereal grain products were being fortified with folic acid. Among 336963 women who underwent antenatal maternal serum screening, the prevalence of orofacial clefts did not change from before (1.15 per 1000) to after (1.21 per 1000) food fortification (prevalence ratio, 1.06; 95% confidence interval, 0.86-1.30).

Canada↗
PubMed2003

Maternal body mass index and the risk of preeclampsia: a systematic overview.

BACKGROUND: Maternal obesity, both in itself and as part of the insulin resistance syndrome, is an important risk factor for the development of preeclampsia. Accurately quantifying the relation between prepregnancy maternal body mass index and the risk of preeclampsia may better identify those at highest risk. We performed a systematic overview of the literature to determine the association between prepregnancy body mass index and the risk of preeclampsia. METHODS: Two reviewers independently retrieved all relevant English language cohort studies through a systematic search of Medline and Embase between 1980 and June 2002. Study data were abstracted in a similar fashion. For each study, the risk ratio of preeclampsia was calculated by comparing the risk of preeclampsia among women with the highest body mass index with those with the lowest. RESULTS: We identified thirteen cohort studies, comprising nearly 1.4 million women. The risk of preeclampsia typically doubled with each 5-7 kg/m2 increase in prepregnancy body mass index. This relation persisted in studies that excluded women with chronic hypertension, diabetes mellitus or multiple gestations, or after adjustment for other confounders. CONCLUSIONS: Most observational studies demonstrate a consistently strong positive association between maternal prepregnancy body mass index and the risk of preeclampsia. Increasing obesity in developed countries is likely to increase the occurrence of preeclampsia. Consideration should be given to the potential benefits of prepregnancy weight reduction programs.

Body Mass Index↗
PubMed2003

Dyslipidemia, statins, and venous thromboembolism: a potential risk factor and a potential treatment.

The optimal drug for the prevention of venous thromboembolism is one that is efficacious, associated with minimal bleeding risk, and easy to administer. Statins fulfill the latter two criteria, but their efficacy remains unproved. By examining the association between dyslipidemia and venous thromboembolism, as well as the evidence that statins might prevent venous thromboembolism, there may be a new rationale for the use of this class of drugs. There may be a common link between arterial and venous thrombosis. Dyslipidemia may be one of the many systemic factors associated not only with arterial thrombosis, but with venous thromboembolism as well. This may occur through the effects of circulating lipid molecules on the vascular endothelium, platelet function, and coagulation factors. By impeding these mechanisms, statins may be protective against venous thrombosis, but epidemiologic studies are few in number, and no randomized clinical trials have been conducted. Better epidemiologic evidence is required to establish whether dyslipidemia is a risk factor for venous thromboembolism. If future observational studies can demonstrate that statins are associated with a lower risk of venous thromboembolism, then consideration should be given to conducting a randomized clinical trial comparing statins with placebo for the prevention of venous thromboembolism. Until then, the efficacy of statins for the prevention or treatment of venous thromboembolism remains uncertain.

Clinical Trials as Topic↗
PubMed2002

Prevention and detection of diabetic embryopathy.

Congenital anomalies are more common in the offspring of women with type 1 and type 2 diabetes mellitus. Herein we define those anomalies more commonly found in the offspring of women with diabetes mellitus, and examine the role of hyperglycemia in their pathogenesis. We then discuss methods for the optimal screening and detection of embryopathy. We conclude by presenting evidence in support of preconception diabetes care to lower the risk of fetal anomalies in women with diabetes mellitus.

Journal Article↗