Family burden of cardiovascular mortality: risk implications for offspring in a national register linkage study based upon the Malmö Preventive Project

Carpal tunnel syndrome

Carpal tunnel syndrome (CTS) is the most common nerve entrapment disorder worldwide. The epidemiology and risk factors, including family burden, for developing CTS are multi-factorial. Despite much research, its intricate pathophysiological mechanism(s) are not fully understood. An underlying subclinical neuropathy may indicate an increased susceptibility to developing CTS. Although surgery is often performed for CTS, clear international guidelines to indicate when to perform non-surgical or surgical treatment, based on stage and severity of CTS, remain to be elucidated. Neurophysiological examination, using electrophysiology or ultrasonography, performed in certain circumstances, should correlate with the history and findings in clinical examination of the person with CTS. History and clinical examination are particularly relevant globally owing to lack of other equipment. Various instruments are used to assess CTS and treatment outcomes as well as the effect of the disorder on quality of life. The surgical treatment options of CTS - open or endoscopic - offer an effective solution to mitigate functional impairments and pain. However, there are risks of post-operative persistent or recurrent symptoms, requiring meticulous diagnostic re-evaluation before any additional surgery. Health-care professionals should have increased awareness about CTS and all its implications. Future considerations of CTS include use of linked national registries to understand risk factors, explore possible screening methods, and evaluate diagnosis and treatment with a broader perspective beyond surgery, including psychological well-being.

Ten-Year Cardiovascular Risk as Predicted by the QRISK®3 Calculator in Diabetic Patients Attending a Tertiary Care Teaching Hospital in Central India and Its Application to Stratify Statin Over-Users and Under-Users

BACKGROUND

Cardiovascular disease (CVD) is an important cause of morbidity and mortality in diabetic patients. As such, risk stratification is essential to identify the risk factors of CVD and provide early intervention. The QRISK®3 tool, recommended by the National Institute for Health and Care Excellence (NICE) guidelines, has the option to choose the patient's ethnicity, which is not available in other tools. However, there is a paucity of data regarding the use of this tool in the Indian population. Therefore, this study was planned to predict 10-year CVD risk using the QRISK®3 tool and to determine statin eligibility in diabetic patients.

METHODS

We enrolled diabetic patients visiting our general medicine outpatient department and diabetic clinic in the study. We collected data from clinical and prescription records, as well as through patient interviews. We analyzed the data to determine the 10-year CVD risk using the QRISK®3 risk tool, which is available online. A cut-off QRISK score of 10%, as recommended by the NICE guidelines (2014), was used to stratify patients as "over-users" and "under-users." We also analyzed the data to determine any correlation between other risk factors and QRISK scores.

RESULTS

Of the 134 diabetic patients recruited in this study, 43 (32.09%) had a CVD risk score of <10%, of which 16 (37.21%) were categorized as "over-users." Of the patients, 91 had a CVD risk score of ≥10%, of which 17 (18.68%) were categorized as "under-users." Risk factors showing a positive correlation with QRISK score included duration of diabetes, age, blood pressure treatment, waist circumference, and non-high-density lipoprotein cholesterol level.

CONCLUSION

QRISK score can be useful to predict 10-year CVD risk in the Indian population and to stratify patients as statin over-users and under-users. This tool can be used in the Indian set-up to identify potential candidates for statin initiation.

Sibling rank and sibling number in relation to cardiovascular disease and mortality risk: a nationwide cohort study

BACKGROUND

The number and rank order of siblings could be of importance for risk of cardiovascular disease and mortality. Previous studies have used only fatal events for risk prediction. We, therefore, aimed to use also non-fatal coronary and cardiovascular events in fully adjusted models.

METHODS

From the Multiple-Generation Register in Sweden, data were used from 1.36 million men and 1.32 million women (born 1932-1960), aged 30-58 years at baseline and with follow-up from 1990 to 2015. Mean age at follow-up was 67 years (range 55-83 years). Fatal and non-fatal events were retrieved from national registers.

RESULTS

Compared with men with no siblings, those with 1-2 siblings had a lower, and those with four or more siblings had a higher adjusted risk of cardiovascular events. Again, compared with men with no siblings, those with more than one sibling had a lower total mortality risk, and those with three or more siblings had an increased risk of coronary events.Correspondingly, compared with women with no siblings those women with three siblings or more had an increased risk of cardiovascular events, and those with two siblings or more had an increased risk of coronary events. Women with one sibling or more were at lower total mortality risk, following full adjustment.

CONCLUSION

Being first born is associated with a favourable effect on non-fatal cardiovascular and coronary events for both men and women. The underlying biological mechanisms for this should be studied in a sociocultural context.

The Malmö Offspring Study (MOS): design, methods and first results

As cardio metabolic disease manifestations tend to cluster in families there is a need to better understand the underlying mechanisms in order to further develop preventive strategies. In fact, genetic markers used in genetic risk scores, important as they are, will not be able alone to explain these family clusters. Therefore, the search goes on for the so called missing heritability to better explain these associations. Shared lifestyle and social conditions in families, but also early life influences may be of importance. Gene-environmental interactions should be explored. In recent years interest has grown for the role of diet-microbiota associations, as microbiota patterns may be shared by family members. In the Malmö Offspring Study that started in 2013, we have so far been able to examine about 4700 subjects (18-71 years) representing children and grandchildren of index subjects from the first generation, examined in the Malmö Diet Cancer Study during 1991 to 1996. This will provide rich data and opportunities to analyse family traits of chronic disease across three generations. We will provide extensive genotyping and phenotyping including cardiovascular and respiratory function, as well as markers of glucose metabolism. In addition, also cognitive function will be assessed. A 4-day online dietary recall will be conducted and gut as well as oral microbiota analysed. The ambition is to provide one of the first large-scale European family studies with individual data across three generations, which could deepen our knowledge about the role of family traits for chronic disease and its underlying mechanisms.

All-Cause Mortality for Life Insurance Applicants with a Family History of Coronary Artery Disease Before 60

OBJECTIVE

-To determine the all-cause mortality of life insurance applicants having a family history of coronary artery disease (CAD) before age 60.

BACKGROUND

-Epidemiological studies have shown that a family history of premature CAD is an independent risk factor for CAD events. The strength of the association between family history and CAD is greatest with earlier age of presentation of CAD in the family member and when multiple family members are affected. Despite earlier insurance studies on this relationship, there is sparse current data on the association between family history of CAD and all-cause mortality in life insurance applicants.

METHODOLOGY

-Life insurance applicants with reported family history of Coronary Artery Disease (CAD) were extracted from data covering United States residents between October 2009 and October 2016. Information about these applicants was matched to the Social Security Death Master (SSDMF) file for deaths occurring from 2009 to 2012 and to another commercially available death source file (Other Death Source, ODS) for deaths occurring from 2009 to 2016 to determine vital status. Actual to Expected (A/E) mortality ratios were calculated using the Society of Actuaries 2015 Valuation Basic Table (2015VBT), select and ultimate table (age last birthday). All expected bases were not smoker distinct. Confidence bands around these mortality ratios were calculated. The variables of interest were applicant age, gender, number of family members with CAD before age 60, and the presence of cardiac or cardiovascular conditions.

RESULTS

-Overall, the mortality of applicants with family members with a history of CAD before age 60 was slightly lower than expected mortality based on the 2015 VBT. Applicants with a cardiac or cardiovascular comorbid condition had a significantly higher mortality ratio. For applicants aged 25-54 and 65-75 with cardiac comorbid conditions, the mortality ratio was 2 times that of those without a cardiac comorbid condition. For those aged 55-64 with cardiovascular comorbid conditions, the mortality ratio was 2.9 times that of those without a cardiovascular comorbid condition. Females had a slightly higher mortality ratio for all age groups, number of family members with CAD before age 60, and cardiovascular conditions.

CONCLUSION

-A family history of CAD before the age of 60 in an insurance applicant may be associated with increased all-cause mortality. Overall in this study, life insurance applicants had a mortality slightly lower than the expected mortality based on the 2015 VBT. However, applicants with a positive family history and a cardiac or cardiovascular comorbid condition had a significantly higher mortality ratio.

Family history of cardiometabolic diseases and its association with arterial stiffness in the Malmö Diet Cancer cohort

OBJECTIVE

Arterial stiffening increases with age and is associated with increased cardiovascular risk. Several risk factors have been shown to predict the development of arterial stiffening; however, a positive family history (FH+) of cardiometabolic disease (CMD) and hypertension has not been extensively studied. We hypothesize that FH+ of CMD plays a significant role in the development of arterial stiffening in offspring.

METHODS

We used data from the population-based Malmö Diet Cancer study (n = 3056) examined in 1992-1996 and again in 2007-2012. Several variables were analysed, including anthropometrics, carotid-femoral pulse wave velocity and FH+. The association between FH+ of CMD and arterial stiffening in the offspring was analysed with analysis of covariance in SPSS. FH+ was subdivided into three categories: family history for cardiovascular events (FH-CVEs), family history for diabetes mellitus type 2 (FH-DM2) and family history for hypertension (FH-HT). The first analysis of covariance-model was adjusted for age, sex, mean arterial pressure and heart rate; the second model additionally adjusted for self-reported medical history in the offspring.

RESULTS

Data indicated that FH-CVE (F = 14.64, P < 0.001), FH-DM2 (F = 18.57, P < 0.001) and FH-HT (F = 13.92, P < 0.001) all significantly increased carotid-femoral pulse wave velocity levels. The results remained when additional adjustment was made for confounders and for self-reported CMD in the index participants, respectively, for FH-CVE (F = 12.47, P < 0.001), FH-DM2 (F = 7.62, P = 0.006) as well as for FH-HT (F = 7.30, P = 0.007).

CONCLUSION

These findings indicate that a FH+ of cardiometabolic conditions and hypertension affects arterial stiffness in offspring independently of haemodynamic factors and self-reported CMD in the offspring without sex differences.

Cigarette smoking and the risk of primary Sjögren's syndrome: a nested case control study

BACKGROUND

Smoking is reported to affect the risk of a number of chronic disorders, including rheumatic diseases. Previous cross-sectional studies have shown a lower frequency of smoking in patients with primary Sjögren's syndrome (pSS). The aim of this study was to investigate the impact of smoking and socioeconomic status on the risk of subsequent diagnosis of pSS in a nested case-control study.

METHOD

Participants in two large population-based health surveys who were later diagnosed with pSS were identified through linkage with the Malmö Sjögren's Syndrome Register. Matched controls were obtained from the health surveys.

RESULTS

Sixty-three patients with pSS with pre-diagnostic data from the health surveys were identified. Current smoking was associated with a significantly lower risk of later being diagnosed with pSS (odds ratio (OR) 0.3; 95% CI 0.1-0.6). Furthermore, former smoking was associated with an increased risk of subsequent pSS diagnosis (OR 4.0; 95% CI 1.8-8.8) compared to never smoking. Similar results were found in a sub-analysis of patients with reported symptom onset after inclusion in the health surveys. Socioeconomic status and levels of formal education had no significant impact on the risk of later being diagnosed with pSS.

CONCLUSION

In this nested case-control study, current smoking was associated with a reduced risk of subsequent diagnosis of pSS. In addition, former smoking was associated with an increased risk. Whether this reflects a biological effect of cigarette smoking or other mechanisms should be further investigated in future studies.

Early Vascular Ageing - A Concept in Development

Cardiovascular disease (CVD) is a prevalent condition in the elderly, often associated with metabolic disturbance and type 2 diabetes. For a number of years, research dedicated to understand atherosclerosis dominated, and for many good reasons, this pathophysiological process being proximal to the CVD events. In recent years, research has been devoted to an earlier stage of vascular pathology named arteriosclerosis (arterial stiffness) and the new concept of early vascular ageing (EVA), developed by a group of mostly European researchers. This overview describes recent developments in research dedicated to EVA and new emerging aspects found in studies of families at high cardiovascular risk. There are new aspects related to genetics, telomere biology and the role of gut microbiota. However, there is still no unifying definition available of EVA and no direct treatment, but rather only recommendations for conventional cardiovascular risk factor control. New interventions are being developed - not only new antihypertensive drugs, but also new drugs for vascular protection - the selective angiotensin-II (AT2) agonist Compound 21 (C21). Human studies are eagerly awaited. Even new functional food products could have the potential to positively influence cardiometabolic regulation, to be confirmed.

Paternal or maternal history of cardiovascular disease and the risk of cardiovascular disease in offspring. A systematic review and meta-analysis

BACKGROUND

Parental history of cardiovascular disease (CVD) is an established risk factor for the development of CVD in offspring. Several studies have suggested that a maternal transmission of CVD is more important for the development of CVD than paternal transmission.

METHODS

A systematic search and meta-analysis were conducted, using the Medline and Embase databases. Included were cohort, case-control and cross-sectional studies (n=26) focusing on the relation between paternal and maternal histories of cardiovascular disease and offspring CVD (myocardial infarction, stroke or cardiovascular mortality). The pooled estimates were calculated using a random-effects model.

RESULTS

The pooled OR of CVD in offspring having a positive paternal history of CVD compared to not having a positive parental history was 1.91 (95% CI 1.56-2.34; I(2)53%), the RR1.54 (95% CI 1.33-1.77; I(2)96%). The OR of a maternal history was 2.16 (95% CI 1.71-2.74; I(2)50%), RR1.59 (95% CI 1.38-1.84; I(2)90%). Regarding different age limits, a maternal history <50 years (3.15, 95% CI 2.18-4.55) and paternal history <55 years (2.82, 95% CI 2.25-3.54) were associated with the highest cardiovascular risk. Additional analyses for sons demonstrated an estimate for a positive paternal history of 1.55 (95% CI 1.39-1.71; I(2)74%) and 1.56 (95% CI 1.46-1.67; I(2)16%) for maternal history. For daughters, the estimate for paternal history was 1.48 (95% CI 1.26-1.74; I(2)73%) and 1.79 (95% CI 1.50-2.13; I(2)68%) for maternal history .

CONCLUSIONS

The conferred risk of CVD in offspring was not substantially different between positive paternal and maternal histories of CVD, the highest risk was observed for maternal history <50years. Since a positive parental history of CVD involves an increased cardiovascular risk, parental history inquiry is useful in clinical practice. No distinction has to be made whether the affected parent is the mother or the father.

The mitochondrial paradigm for cardiovascular disease susceptibility and cellular function: a complementary concept to Mendelian genetics

While there is general agreement that cardiovascular disease (CVD) development is influenced by a combination of genetic, environmental, and behavioral contributors, the actual mechanistic basis of how these factors initiate or promote CVD development in some individuals while others with identical risk profiles do not, is not clearly understood. This review considers the potential role for mitochondrial genetics and function in determining CVD susceptibility from the standpoint that the original features that molded cellular function were based upon mitochondrial-nuclear relationships established millions of years ago and were likely refined during prehistoric environmental selection events that today, are largely absent. Consequently, contemporary risk factors that influence our susceptibility to a variety of age-related diseases, including CVD were probably not part of the dynamics that defined the processes of mitochondrial-nuclear interaction, and thus, cell function. In this regard, the selective conditions that contributed to cellular functionality and evolution should be given more consideration when interpreting and designing experimental data and strategies. Finally, future studies that probe beyond epidemiologic associations are required. These studies will serve as the initial steps for addressing the provocative concept that contemporary human disease susceptibility is the result of selection events for mitochondrial function that increased chances for prehistoric human survival and reproductive success.

The role of conventional and novel mechanisms in explaining increased risk of cardiovascular events in offspring with positive parental history

BACKGROUND

Parental history is a widely accepted risk factor for offspring cardiovascular events, although the mechanisms remain unclear. We examined the contribution of conventional and novel risk factors in explaining the excess risk of cardiovascular events in offspring with positive parental history (PH+).

METHODS AND RESULTS

We collected conventional (blood pressure, cholesterol, adiposity), lifestyle, and novel (C-reactive protein, CRP) risk factors at baseline in participants from the Scottish Health Surveys (n = 5946, 44.5% men, aged 53.6 +/- 12.4 years), who were followed up over an average of 7.1 years for cardiovascular disease (CVD) events (a composite of fatal and nonfatal events incorporating acute myocardial infarction, coronary artery bypass surgery, percutaneous coronary angioplasty, stroke, heart failure). Younger PH+ participants (<65 years) were at higher risk of incident CVD events [age-adjusted and sex-adjusted hazard ratio = 1.91, 95% confidence interval (CI) 1.21-3.00] compared with PH-. Despite an association of PH+ with blood pressure, total and high-density lipoprotein cholesterol, CRP, and physical activity, less than 15% of the excess risk was explained through conventional and novel risk factors. However, the greatest risk of CVD was observed in PH+ participants with elevated CRP (> or =3 mg/l) (hazard ratio = 2.99, 95% CI 2.15-4.16) or hypertension (hazard ratio = 2.87, 95% CI 2.07-3.99).

CONCLUSION

Only a small amount of the excess CVD risk associated with PH+ is accounted for by conventional and novel mechanisms. However, the combination of elevated CRP or hypertension with PH+ substantially increases the risk of CVD.

Maternal cardiovascular disease risk in relation to the number of offspring born small for gestational age: national, multi-generational study of 2.7 million births

AIM

To investigate the risk of small for gestational age (SGA) births in relation to maternal history of cardiovascular disease (CVD) across two generations and additionally to analyse maternal CVD risk based on number of SGA offspring.

METHODS

We used register data from 1.4 million women and 2.7 million offspring. The outcome measures were risk of being SGA in relation to maternal total CVD (n = 10 436) across two generations, as well as risk of CVD in mothers in relation to the number of their SGA offspring, stratified by educational level.

RESULTS

Compared to no family history of CVD (reference) the hazard ratio (HR) for being SGA in female offspring was 1.11 (95% confidence interval (CI) 1.09-1.13) for a positive maternal history of CVD. The highest risk was shown in daughters when both the mother and the grandmother had a history of CVD (HR 1.32, 95% CI 1.24-1.39). There was a stepwise increased risk of CVD events in mothers in relation to the number of their SGA offspring (HR 1.41-1.86) when 'no SGA offspring' was used as reference. The risk of CVD in relation to SGA status was increased in the least educated group (HR 2.7-5.0) compared to the group with the highest level of education with no SGA offspring.

CONCLUSION

The risk of SGA offspring and the risk of maternal CVD are mutually interdependent and both conditions increased in women with a low level of education.

Common variants in the TCF7L2 gene help to differentiate autoimmune from non-autoimmune diabetes in young (15-34 years) but not in middle-aged (40-59 years) diabetic patients

AIMS/HYPOTHESIS

Type 1 diabetes in children is characterised by autoimmune destruction of pancreatic beta cells and the presence of certain risk genotypes. In adults the same situation is often referred to as latent autoimmune diabetes in adults (LADA). We tested whether genetic markers associated with type 1 or type 2 diabetes could help to discriminate between autoimmune and non-autoimmune diabetes in young (15-34 years) and middle-aged (40-59 years) diabetic patients.

METHODS

In 1,642 young and 1,619 middle-aged patients we determined: (1) HLA-DQB1 genotypes; (2) PTPN22 and INS variable-number tandem repeat (VNTR) polymorphisms; (3) two single nucleotide polymorphisms (rs7903146 and rs10885406) in the TCF7L2 gene; (4) glutamic acid decarboxylase (GAD) and IA-2-protein tyrosine phosphatase-like protein (IA-2) antibodies; and (5) fasting plasma C-peptide.

RESULTS

Frequency of risk genotypes HLA-DQB1 (60% vs 25%, p = 9.4 x 10(-34); 45% vs 18%, p = 1.4 x 10(-16)), PTPN22 CT/TT (34% vs 26%, p = 0.0023; 31% vs 23%, p = 0.034), INS VNTR class I/I (69% vs 53%, p = 1.3 x 10(-8); 69% vs 51%, p = 8.5 x 10(-5)) and INS VNTR class IIIA/IIIA (75% vs 63%, p = 4.3 x 10(-6); 73% vs 60%, p = 0.008) was increased in young and middle-aged GAD antibodies (GADA)-positive compared with GADA-negative patients. The type 2 diabetes-associated genotypes of TCF7L2 CT/TT of rs7903146 were significantly more common in young GADA-negative than in GADA-positive patients (53% vs 43%; p = 0.0004). No such difference was seen in middle-aged patients, in whom the frequency of the CT/TT genotypes of TCF7L2 was similarly increased in GADA-negative and GADA-positive groups (55% vs 56%).

CONCLUSIONS/INTERPRETATION

Common variants in the TCF7L2 gene help to differentiate young but not middle-aged GADA-positive and GADA-negative diabetic patients, suggesting that young GADA-negative patients have type 2 diabetes and that middle-aged GADA-positive patients are different from their young GADA-positive counterparts and share genetic features with type 2 diabetes.

The prevalence of metabolic syndrome among US women of childbearing age

OBJECTIVES

We sought to determine whether the prevalence of metabolic syndrome among US women of childbearing age (18-44 years) has increased since 1988 and to estimate its current prevalence by race/ethnicity and risk that a maternal history of select metabolic syndrome characteristics imposes on offspring.

METHODS

We used survey-specific data analysis methods to examine data from the National Health and Nutrition Examination Surveys conducted from 1988 to 2004.

RESULTS

The prevalence of the metabolic syndrome phenotype and 2 of its clinical correlates significantly increased between 1988 and 2004 (increase for metabolic syndrome phenotype=7.6%, for obesity=13.3%, and for elevated C-reactive protein=10.6%; P < .001 for all 3). Hispanic women were more likely than were White women to possess the phenotype (P = .004). Women who reported that their mothers had been diagnosed with diabetes were more likely to possess the phenotype than those whose mothers had not been so diagnosed (odds ratio=1.9; 95% confidence interval=1.3, 2.8).

CONCLUSIONS

The current trends of metabolic syndrome among women of childbearing age demonstrate the need for additional rigorous investigations regarding its long-term effects in these women and their offspring.

Early vascular aging (EVA): consequences and prevention

It has often been recognized that a discrepancy exists during the clinical consultation between the chronological age of a patient on the one hand with the signs and symptoms of biological age that can be recorded on the other hand. In cardiovascular medicine this is obvious when a heavy smoker presents with features of early biological aging, for example skin appearance and impaired lung function. This could also be extrapolated to vascular function as the target for numerous cardiovascular risk factors, thereby increasing the risk of early cardiovascular disease (CVD). Both new and old treatment modalities can play a role for the prevention of early vascular aging, first of all smoking cessation and improved lifestyle in general, but later on also the use of drugs such as statins or agents that block the renin-angiotensin system (RAS). New classes of drugs are currently being tested for CVD prevention, including glitazones and rimonabant, even if adverse effects (heart failure and depression) might restrict their usefulness. Results from ongoing intervention studies will eventually cast new light on possibilities to prevent the development of vascular aging.

Parental occurrence of premature cardiovascular disease predicts increased coronary artery and abdominal aortic calcification in the Framingham Offspring and Third Generation cohorts

BACKGROUND

Parental premature cardiovascular disease (CVD) is a risk factor for coronary heart disease (CHD). We related validated parental premature CVD with the subclinical measures of coronary artery (CAC) and abdominal aortic (AAC) calcification in the community.

METHODS AND RESULTS

We studied 2 generations of Framingham Heart Study subjects who underwent multidetector computed tomography measurements of CAC and AAC and who had 2 parents in the study. Subjects included 797 Framingham Offspring (mean age, 63 years; 56% women) and 1238 Third Generation (Gen3) (mean age, 46 years; 47% women) participants free of CVD. Generalized estimating equations adjusted for major CVD risk factors were used to relate validated parental premature CVD and CHD to CAC and AAC, defined by >90th percentile age- and sex-specific cut points from a healthy subsample. Parental premature CVD was associated with CAC among Gen3 (odds ratio=2.17 [1.41 to 3.33]; P<0.001) and nonsignificantly among Offspring (odds ratio=1.42 [0.91 to 2.22]; P=0.12). Parental premature CHD was associated with CAC among Gen3 (odds ratio=2.22 [1.22 to 4.01]) but not Offspring. Parental premature CVD was not associated with AAC in either cohort. Parental premature CHD was associated with AAC among Gen3 (odds ratio=1.65 [0.99 to 2.75]; P=0.05) but not among Offspring. The magnitude of risk conferred was greater for paternal than maternal premature CVD.

CONCLUSIONS

Parental premature CVD is associated with CAC, and premature CHD is associated with AAC, after adjustment for risk factors, particularly in younger middle-aged adults. Risk conferred by parental premature CVD on vascular calcification may be mediated through novel mechanisms not accounted for by classic CVD risk factors known to cause atherosclerosis.

Derivation and validation of QRISK, a new cardiovascular disease risk score for the United Kingdom: prospective open cohort study

OBJECTIVE

To derive a new cardiovascular disease risk score (QRISK) for the United Kingdom and to validate its performance against the established Framingham cardiovascular disease algorithm and a newly developed Scottish score (ASSIGN).

DESIGN

Prospective open cohort study using routinely collected data from general practice.

SETTING

UK practices contributing to the QRESEARCH database.

PARTICIPANTS

The derivation cohort consisted of 1.28 million patients, aged 35-74 years, registered at 318 practices between 1 January 1995 and 1 April 2007 and who were free of diabetes and existing cardiovascular disease. The validation cohort consisted of 0.61 million patients from 160 practices.

MAIN OUTCOME MEASURES

First recorded diagnosis of cardiovascular disease (incident diagnosis between 1 January 1995 and 1 April 2007): myocardial infarction, coronary heart disease, stroke, and transient ischaemic attacks. Risk factors were age, sex, smoking status, systolic blood pressure, ratio of total serum cholesterol to high density lipoprotein, body mass index, family history of coronary heart disease in first degree relative aged less than 60, area measure of deprivation, and existing treatment with antihypertensive agent.

RESULTS

A cardiovascular disease risk algorithm (QRISK) was developed in the derivation cohort. In the validation cohort the observed 10 year risk of a cardiovascular event was 6.60% (95% confidence interval 6.48% to 6.72%) in women and 9.28% (9.14% to 9.43%) in men. Overall the Framingham algorithm over-predicted cardiovascular disease risk at 10 years by 35%, ASSIGN by 36%, and QRISK by 0.4%. Measures of discrimination tended to be higher for QRISK than for the Framingham algorithm and it was better calibrated to the UK population than either the Framingham or ASSIGN models. Using QRISK 8.5% of patients aged 35-74 are at high risk (20% risk or higher over 10 years) compared with 13% when using the Framingham algorithm and 14% when using ASSIGN. Using QRISK 34% of women and 73% of men aged 64-75 would be at high risk compared with 24% and 86% according to the Framingham algorithm. UK estimates for 2005 based on QRISK give 3.2 million patients aged 35-74 at high risk, with the Framingham algorithm predicting 4.7 million and ASSIGN 5.1 million. Overall, 53 668 patients in the validation dataset (9% of the total) would be reclassified from high to low risk or vice versa using QRISK compared with the Framingham algorithm.

CONCLUSION

QRISK performed at least as well as the Framingham model for discrimination and was better calibrated to the UK population than either the Framingham model or ASSIGN. QRISK is likely to provide more appropriate risk estimates to help identify high risk patients on the basis of age, sex, and social deprivation. It is therefore likely to be a more equitable tool to inform management decisions and help ensure treatments are directed towards those most likely to benefit. It includes additional variables which improve risk estimates for patients with a positive family history or those on antihypertensive treatment. However, since the validation was performed in a similar population to the population from which the algorithm was derived, it potentially has a "home advantage." Further validation in other populations is therefore required.

Body mass index in late adolescence and its association with coronary heart disease and stroke in middle age among Swedish men

BACKGROUND AND OBJECTIVES

Body mass index (BMI) in adolescence may be of particular importance as a predictor of future risk of coronary heart disease (CHD). Associations measured either in childhood or in middle age have appeared to be weaker or non-existent. We investigated the association between BMI measured in adolescence and CHD, and also stroke, among middle aged Swedish men and controlled for potential confounders not included in previous studies.

METHODS

Data on BMI, smoking and blood pressure (diastolic and systolic) was collected from 49,321 Swedish males, born during 1949-1951, at conscription for military service in 1969/70. Census data on socioeconomic indicators in childhood and adulthood was linked to the cohort. The men were followed from 1991 through 2004 in national registers with regard to mortality and hospitalization from CHD and stroke.

RESULTS

A graded increase of CHD was seen in over six levels of BMI (BMI<18.5, hazard ratio (HR)=1.0, BMI=18.5-20.99 (reference category), BMI=21-22.99, HR=1.2; BMI=23-24.99, HR=1.5; BMI=25-29.99, HR=2.5; BMI > or =30, HR=4.3). A graded association between BMI and stroke was also found, although weaker. Adjustments for cardiovascular risk factors (smoking, diastolic and systolic blood pressure, and early cardiovascular mortality in parents) attenuated the relative risks to some extent, whereas adjustments for socioeconomic indicators in childhood and adulthood had minor effects.

CONCLUSION

The results strongly suggest that BMI in late adolescence is an important predictor of both CHD and stroke among men before age 55 years, independent of smoking, hypertension and early cardiovascular mortality in parents.

Population-attributable risk of coronary heart disease risk factors during long-term follow-up: the Malmö Preventive Project

AIMS

To calculate the population-attributable risk (PAR) of coronary events (CE) from 10 risk factors, during long-term follow-up.

METHODS

We used both case-cohort and case-control analyses for calculation of PAR in relation to 10 baseline risk factors. First CE (fatal or nonfatal, n=3072) in 22,444 males and 10,902 females was recorded during a mean follow-up of 20 years by use of national registers.

RESULTS

Using a Cox regression analysis in a case-cohort design, smoking (prevalence in men 49%, women 37%) was the strongest risk factor, RR 2.29 (95% CI 2.09-2.52; PAR 39%), followed by hypercholesterolaemia, RR 1.70 (95% CI 1.56-1.86; PAR 18%), and diabetes, RR 1.67 (95% CI 1.41-1.99; PAR 3%). For women the strongest risk factors were smoking, RR 3.16 (95% CI 2.50-3.98; PAR 44%), diabetes, RR 2.59 (95% CI 1.78-3.76; PAR 6%), and hypertension, RR 2.47 (95% CI 1.94-3.14; PAR 23%). In men, smoking was the strongest predictor both after 10 years [RR 2.69 (95% CI 2.23-3.24)] and 20 years [RR 2.45 (95% CI 2.15-2.79)], followed by hypercholesterolaemia (RR 2.16-1.63), hypertension (RR 2.04-1.51), and diabetes (RR 1.85 -1.47). The case-control design gave very similar results. Total PAR varied from 74% (fully adjusted Cox regression, case-control, in men) to 116% in women (case-cohort).

CONCLUSION

Smoking is the most important long-term risk factor for CE in both genders, based on data from a population with a high proportion of smokers. Ten measured variables explained almost all variation in risk and could be used as a basis for intervention programmes.

Gene by sex interaction in the etiology of coronary heart disease and the preceding metabolic syndrome

BACKGROUND

Despite decades of research, the genetic basis of coronary heart disease and its metabolic risk factors is poorly understood. Few studies consider that sex may modify the effect of gene variants on disease. Investigation of gene by sex interaction may help to elucidate underlying genetic susceptibilities and explain the sexual dimorphism of these complex traits.

AIMS

The aim of this review is to summarize evidence for gene by sex interaction in the etiology of coronary heart disease and the metabolic syndrome.

DATA SYNTHESIS

Published literature was examined in the areas of familial aggregation of coronary heart disease; heritability of body mass, insulin resistance, hypertension and dyslipidemia; genome-wide linkage analysis in humans and rodents; and large-scale genetic association studies. Possible mechanisms of gene by sex interaction are discussed including X-linked inheritance, confounding by risk factors and the effect of sex hormones.

CONCLUSIONS

The strongest evidence for gene by sex interaction in relation to coronary heart disease and the metabolic syndrome is in the etiology of body mass, insulin resistance and possibly dyslipidemia. Genetic studies of these traits would benefit from taking sex differences into account. Alternative mechanisms underlying gene by sex interaction, besides obvious sex hormone differences, should be considered.