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Objective: Arterial stiffness and exposure to psychosocial work-related factors increase the risk of developing cardiovascular disease. However, little is known about the relationship between psychosocial work-related factors and arterial stiffness. We aimed to examine this relationship., Design: Prospective cohort study., Setting: Public organisations in Quebec City, Canada., Participants: The study included 1736 white-collar workers (women 52%) from 19 public organisations., Primary and Secondary Outcome Measures: Association between psychosocial work-related factors from the job strain and effort-reward imbalance (ERI) models assessed at study baseline (1999-2001) with validated instruments and arterial stiffness assessed using carotid-femoral pulse wave velocity at follow-up, on average 16 years later (2015-2018). Generalised estimating equations were used to estimate differences in arterial stiffness between exposed and unexposed participants. Subgroup analyses according to sex, age, blood pressure (BP), cardiovascular risk score and employment status were conducted., Results: Among participants with high diastolic BP (≥90 mm Hg) at baseline, aged 47 on average, those exposed to high job strain had higher arterial stiffness (1.38 m/s (95% CI: 0.57 to 2.19)) at follow-up, 16 years later, following adjustment for a large set of potential confounders. The trend was similar in participants with high systolic BP (≥140 mm Hg) exposed to high job strain (0.84 m/s (95% CI: -0.35 to 2.03)). No association was observed for ERI in the total sample and counterintuitive associations were observed in subgroup analyses., Conclusions: Job strain may have a long-term deleterious effect on arterial stiffness in people with high BP. Interventions at midlife to reduce job strain may mitigate arterial stiffness progression., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The Canadian Network and Centre for Trials INternationally (CANNeCTIN) was jointly funded by the Canadian Institutes of Health Research and the Canadian Foundation for Innovation in April 2008 to provide infrastructure for clinical studies of cardiovascular diseases and diabetes mellitus. Its functional components include a national coordinating centre at the Population Health Research Institute (PHRI) in Hamilton (Ontario), a collaborative Canadian network and an affiliated international network of hospitals and clinics. The rationales for CANNeCTIN include the global health burden of cardiovascular diseases and diabetes, the strengths of randomized controlled trials - particularly large, multicentre and international - and the track record of success of the PHRI. CANNeCTIN will provide investigators from across Canada with opportunities to become the principal investigators of national and international trials coordinated by the PHRI. CANNeCTIN will support priority pilot studies, and successful investigators will be encouraged and assisted to apply for peer review and industrial funding for full studies to be conducted within the network and coordinated by the PHRI. An extensive education program offers hands-on experience in organizing and leading large national⁄international clinical trials led by accomplished researchers, distance learning courses in clinical research methodology, biostatistics and study coordination, and 'cutting-edge' workshops. A knowledge translation program seeks opportunities arising from clinical trials and encourages research into this paradigm for understanding how best to close the gaps between knowledge and effective practice. The five-year goals are to enhance the capacity of Canadian investigators to lead major clinical studies, facilitate knowledge translation and exchange, and augment Canada's capacity to train the next generation of leaders in cardiovascular and diabetes clinical research.

Background: Despite its widespread use, limited data on the validity of the Canadian Cardiovascular Society angina (CCSA) classification relative to other measures of functional status have been reported., Objective: To assess the validity of the CCSA classification by comparing it with the Duke Activity Status Index (DASI) and evaluate its prognostic significance with respect to long-term mortality., Methods: The study population consisted of 1407 patients who underwent cardiac catheterization between 1992 and 1996. The median follow-up period was 9.7 years (interquartile range 6.1 to 11.1 years) and the mortality status as of December 31, 2004 was available for all patients., Results: The first three CCSA classes were inversely related to the DASI. The mean (+/- SD) scores were as follows: class I, 31.4+/-16.7; class II, 22.5+/-15.4; class III, 14.7+/-14.3; and class IV, 15.5+/-14.9 (P<0.01). Increasing CCSA class was associated with increased long-term mortality, even after adjusting for baseline characteristics. Chest pain course was also an important modulator of mortality among class III and IV patients; one-year mortality rates were 8.1% among unstable patients compared with 4.8% among patients with stable or progressing course., Conclusion: CCSA classes I to III were inversely related to DASI scores and linearly associated with mortality. The similarity in outcomes among class III and IV patients is probably explained by the confounding effect of the stability of the patients' symptoms. The higher mortality risk among class III and IV patients with an unstable course provides impetus for a revised CCSA definition incorporating this information.

Background: The current interpretation of the increased risk of ischemic heart disease (IHD) associated with reduced low density lipoprotein (LDL) particle size is based entirely on data derived from relatively small case-control studies, with a lack of evidence from large, prospective, population-based cohort data., Objectives: To investigate the association between LDL particle size and incident IHD on the basis of data from the entire population-based, prospective cohort of men from the Quebec Cardiovascular Study., Patients and Methods: Analyses were conducted in a cohort of 2057 men who were all initially free of IHD, and who were followed up over a five-year period, during which 108 first IHD events (myocardial infarction, angina or coronary death) were recorded. LDL particle size was measured by nondenaturing gradient gel electrophoresis., Results: Cox proportional hazards analysis indicated that the relationship between LDL particle size and the risk of future IHD events was not linear. Men with an LDL particle size less than 256.0 A had a significant 2.2-fold increase in the five-year rate of IHD (P<0.001) compared with men having an LDL particle size greater than 256.0 A. Multivariate and subgroup analyses indicated that small, dense LDL particles predicted the rate of IHD independent of LDL cholesterol, triglycerides, high density lipoprotein (HDL) cholesterol, apolipoprotein B and the total cholesterol to HDL cholesterol ratio. Finally, the magnitude of the increase in IHD risk attributed to lipid risk factors was modulated to a significant extent by variations in LDL particle size., Conclusions: The present study provides the first large scale, population-based, prospective evidence supporting the hypothesis that small, dense LDL particles may be associated with an increased risk of IHD. The results also suggest that information on LDL diameter may improve the ability to predict IHD risk accurately over traditional lipid variables.

Objective: To investigate the possibility that leptin levels may be predictive of the risk of ischemic heart disease (IHD) through the relationship of leptin to body fat., Research Design and Methods: The Quebec Cardiovascular Study cohort consisted of 2,103 French-Canadian men without IHD in 1985 who were followed until 1990, by which time 114 had experienced an IHD event. These 114 men were then individually matched for age, BMI, cigarette smoking, and alcohol intake with 114 subjects who were free of IHD at follow-up. After exclusion of diabetic patients and those in whom leptin levels could not be measured, we were able to compare the initial metabolic profiles of 86 men in the IHD group and of 95 control subjects., Results: Plasma leptin concentrations were positively correlated with BMI (r = 0.67, P < 0.0001) and with fasting insulin concentrations (r = 0.46, P < 0.0001) in the overall sample. These significant associations were also observed when men with IHD and the control subjects were examined separately (control subjects: r = 0.68 for BMI and r = 0.45 for insulin; IHD subjects: r = 0.65 for BMI and r = 0.50 for insulin). With the exception of plasma triglyceride (r = 0.25, P < 0.001), no significant association was found between leptin and plasma lipoprotein and lipid concentrations. Furthermore, plasma insulin remained significantly associated with leptin levels even after adjustment for BMI (r = 0.22, P < 0.005). There was no difference in baseline leptin levels among men who developed IHD versus men who remained IHD-free during the 5-year follow-up (5.56 +/- 3.12 vs. 5.36 +/- 2.90 ng/ml, respectively). Thus, although significantly correlated with the BMI and fasting insulin levels, plasma leptin concentration was not a significant predictor of the 5-year incidence of IHD. This lack of a relationship to IHD was noted when leptin levels were analyzed as tertiles and when leptin concentration was analyzed as a continuous variable., Conclusions: These prospective results suggest that leptinemia, despite being a strong correlate of obesity, does not appear to be an independent risk factor for the development of IHD in men.

Objective: To provide health care professionals with guidelines on the use of blood pressure self-measurement., Methods: Recommendations were devised after consideration of expert reviews and guidelines, personal files, international standards documents, personal communication with investigators and the results of a MEDLINE search (1966-94) using the term 'blood pressure determination'., Benefits, Harms, Costs: Self-measurement of blood pressure can be used to detect white coat hypertension, monitor changes in blood pressure closely, more rapidly achieve desired blood pressure goals, increase adherence to antihypertensive therapy and improve patient self-reliance. However, self-measured blood pressure readings may be misleading because there is insufficient normative, prognostic and outcome data and because some patients may not take accurate measurements. The use of self-measurement of blood pressure has a relatively small direct cost and may result in an overall reduction in treatment costs., Recommendations: Self-measured blood pressure readings can be a valuable supplement to clinic (or office) blood pressure readings. However, self-measurement is appropriate neither for patients who are physically or mentally incapable of accurate assessment and interpretation of readings nor for those who do not want to participate. Patients who self-monitor blood pressure require careful training in blood pressure measurement and instruction on the recording and interpretation of blood pressure readings. Advice to patients using monitoring equipment must take into account the needs and abilities of the patient. Although only a few electronic devices for the self-measurement of blood pressure have met recommended performance standards, their use may be more appropriate for some patients and the training requirements fewer than if manual devices are used., Validation: The guidelines of several expert groups were examined in the preparation of these recommendations. The recommendations were presented at the World Conference on Hypertension Control in 1995 and were reviewed by the parent societies of the Canadian Coalition for High Blood Pressure Prevention and Control.

In an attempt to retrain family doctors in hypertension and hyperlipoproteinemia, computer assisted instruction (CAI) was assessed in fourteen doctors (Group 1) and its efficiency was compared to that of traditional lectures given to twenty-one doctors (Group 2). The same objectives, contents and illustrations were used in both teaching approaches. There was no significant difference for age, year of graduation and type of practice in the two groups. Comparison between pre-test and immediate post-test revealed a significant gain of knowledge for hyperlipoproteinemia (group 1, 33% and group 2, 22%) and hypertension (group 1, 16% and Group 2, 19%). A year later a similar post-test was done in both groups, and no significant difference was found between this late post-test and the pre-test. CAI applied to family doctors is as efficient for learning as traditional lectures, and both approaches failed to show retention of knowledge after one year. This is perhaps the result of having selected instructional objectives of theoretical more than practical value.

Causal blood pressure measurements were recorded in two groups of men aged 40 to 64 years; of the 7024 men in metropolitan Saint John, NB, and the 4044 men in seven suburbs of Quebec who were asked, 5840 (83.1%) and 3097 (76.6%) respectively agreed to participate. Of the Saint John group 9.0% were taking antihypertensive drugs, as compared with only 3.3% of the Quebec group (p less than 0.0001). Among the treated subjects 33% in Saint John and 53% in Quebec still had a diastolic pressure greater than 95 mm Hg (p less than 0.01). Among the participants not taking antihypertensive drugs the systolic blood pressure increased with age, but the diastolic blood pressure increased only slightly up to 55 years of age and then decreased. On average the subjects in Saint John who were not being treated had a systolic pressure 6.2 mm Hg lower and a diastolic blood pressure 3.6 mm Hg lower than their Quebec counterparts (p less than 0.0001). This difference was observed in all the age groups and was not the result of the treatment of a greater proportion of the Saint John cohort. Despite the higher blood pressures and the smaller number receiving adequate treatment in the Quebec group, the rate of death due to coronary artery disease was 10% lower than that in the Saint John group. A bias in the data from Quebec may have influenced the magnitude of the differences between the two samples, but if present it should have underestimated the blood pressures in the Quebec group and therefore not have changed the outcome.