Know Your Heart: Rationale, design and conduct of a cross-sectional study of cardiovascular structure, function and risk factors in 4500 men and women aged 35-69 years from two Russian cities, 2015-18

Russia has one of the highest rates of cardiovascular disease in the world. The International Project on Cardiovascular Disease in Russia (IPCDR) was set up to understand the reasons for this. A substantial component of this study was the Know Your Heart Study devoted to characterising the nature and causes of cardiovascular disease in Russia by conducting large cross-sectional surveys in two Russian cities Novosibirsk and Arkhangelsk. The study population was 4542 men and women aged 35-69 years recruited from the general population. Fieldwork took place between 2015-18. There were two study components: 1) a baseline interview to collect information on socio-demographic characteristics and cardiovascular risk factors, usually conducted at home, and 2) a comprehensive health check at a primary care clinic which included detailed examination of the cardiovascular system. In this paper we describe in detail the rationale for, design and conduct of these studies.

Sex Differences in the Impact of Body Mass Index on the Risk of Future Atrial Fibrillation: Insights From the Longitudinal Population-Based Tromsø Study

Background

Atrial fibrillation (AF) prevalence is increasing, and body mass index (BMI) is a risk factor for AF. However, sex differences in the impact of BMI on AF risk have not been fully elucidated.

Methods and Results

Data from the fourth survey (1994–1995) of the Tromsø Study (Norway) were used to investigate the association of single‐measurement BMI on future AF risk. To analyze the influence of BMI changes on AF risk, data from individuals who attended the third and fourth study surveys were used. AF diagnosis was derived from record linkage and end point adjudication. Cox regression analysis was conducted using fractional polynomials of BMI and BMI change with models adjusted for age, baseline BMI (change analyses), risk factors, comorbidities, and antihypertensive medications.

Data were available for 24 799 individuals from the fourth survey (mean age, 45.5±14.2 years; 52.9% women). Over 15.7±5.5 years, 811 women (6.2%) and 918 men (7.9%) developed AF. In men, lower BMI decreased AF risk and higher BMI increased risk (hazard ratios [95% confidence intervals] for BMI 18 or 40 kg/m² compared with 23 kg/m² were 0.75 [0.70–0.81] and 4.42 [3.00–6.53], respectively). The same pattern was identified in women. Two surveys were attended by 14 652 individuals. In men and women, a decrease in BMI over time was associated with decreased AF risk and an increase in BMI was associated with increased AF risk.

Conclusions

Within a population cohort, BMI was positively associated with AF risk. Change in BMI over time influenced AF risk in both men and women.

Secondary prevention care and effect: Total and low-density lipoprotein cholesterol levels and lipid-lowering drug use in women and men after incident myocardial infarction – The Tromsø Study 1994–2016

Background: Secondary prevention guidelines after myocardial infarction (MI) are gender neutral, but underutilisation of treatment in women has been reported. Design: We investigated the change in total and low-density lipoprotein (LDL) cholesterol levels and lipid-lowering drug (LLD) use after first-ever MI in a population-based study. Methods: We followed 10,005 participants (54% women) attending the Tromsø Study 1994–1995 and 8483 participants (55% women) attending the Tromsø Study 2007–2008 for first-ever MI up to their participation in 2007–2008 and 2015–2016, respectively. We used linear and logistic regression models to investigate sex differences in change in lipid levels. Results: A total of 395 (MI cohort I) and 132 participants (MI cohort II) had a first-ever MI during 1994–2008 and 2007–2013, respectively. Mean change in total cholesterol was −2.34 mmol/L (SD 1.15) in MI cohort I, and in LDL cholesterol was −1.63 mmol/L (SD 1.12) in MI cohort II. Men had a larger decrease in lipid levels compared to women: the linear regression coefficient for change was −0.33 (95% confidence interval [CI] −0.51 to −0.14) for total cholesterol and −0.21 (95% CI −0.37 to −0.04) for LDL cholesterol, adjusted for baseline lipid value, age and cohort. Men had 73% higher odds (95% CI 1.15−2.61) of treatment target achievement compared to women, adjusted for baseline lipid value, age and cohort. LLD use was reported in 85% of women and 92% of men in MI cohort I, and 80% in women and 89% in men in MI cohort II. Conclusions: Compared to men, women had significantly less decrease in lipid levels after MI, and a smaller proportion of women achieved the treatment target.

Blood pressure target achievement and antihypertensive medication use in women and men after first-ever myocardial infarction: the Tromsø Study 1994-2016

Background

Recurrent cardiovascular events after myocardial infarction (MI) are frequent, and gender differences in blood pressure treatment have been reported. Despite increased focus on secondary prevention, recent reports indicate that treatment targets are not achieved. There is a need for gender-specific analyses of post-MI blood pressure treatment target achievement and antihypertensive medication adherence.

Design

We investigated the change in systolic and diastolic blood pressure and antihypertensive drug use after first-ever MI over two time periods in a Norwegian population-based study.

Methods

We followed 10 089 participants (55% women) attending the Tromsø Study in 1994-1995 (MI-cohort I) and 8412 participants (55% women) attending the Tromsø Study 2007-2008 (MI-cohort II) for first-ever MI up to their participation in 2007-2008 and 2015-2016, respectively. We used linear regression models to investigate sex and age differences in change in blood pressure.

Results

A total of 396 participants in MI-cohort I and 131 participants in MI-cohort II had a first-ever MI in the observation periods. In MI-cohort I, 35% of the women and 52% of the men achieved the treatment targets of blood pressure <140/90 mm Hg (130/80 mm Hg if diabetic), while the proportions for MI-cohort II were 50% and 54% for women and men, respectively. Antihypertensive use was reported in 88% of women and 87% of men in MI-cohort I, and 76% of women and 81% of men in MI-cohort II.

Conclusions

We found an overall low achievement of the treatment target. The findings call for better strategies for secondary prevention for both women and men.

CHA2DS2-VASc score, left atrial size and atrial fibrillation as stroke risk factors in the Tromsø Study

Objective

CHA₂DS₂-VASc score, left atrial (LA) size and atrial fibrillation (AF) have individually been associated with stroke risk. Our aim was to investigate the predictive ability of combinations of these factors for the odds of incident stroke in a population-based cohort study.

Methods

We followed 2844 participants from the Tromsø Study from 1994 to 2012. Information on LA size and CHA₂DS₂-VASc score (age, sex, congestive heart failure, hypertension, vascular disease, stroke and diabetes) were obtained at baseline. AF status was recorded from medical records. The outcome measure was all strokes. The association between covariates and stroke was investigated by means of multivariate logistic regression analysis.

Results

A total of 325 participants (45% women, mean age at baseline 59.3 years) had a stroke. Incidence rates for stroke were 6.4 in women and 8.4 in men per 1000 person-years. Participants with CHA₂DS₂-VASc ≥1 and LA size <2.8 had ∼4 times (95% CI 2.6 to 5.3) increased odds of stroke, whereas participants with CHA₂DS₂-VASc ≥1 and LA size ≥2.8 had ∼9 times (95% CI 5.3 to 16.4) increased odds of stroke, compared with participants with CHA₂DS₂-VASc score 0, irrespective of AF status. Adjustment for significant covariates had minimal impact on the OR estimates.

Conclusions

Combining CHA₂DS₂-VASc score ≥1 and enlarged LA size identified participants with high odds of stroke regardless of AF status.

Association between diastolic dysfunction and future atrial fibrillation in the Tromsø Study from 1994 to 2010

Objective

To investigate the association between echocardiographic measurements with emphasis on diastolic dysfunction and risk of atrial fibrillation (AF) in a population-based cohort study.

Methods

We followed 2406 participants from the Tromsø Study from 1994 to 2010. Left atrial (LA) size and mitral Doppler indices as measured by echocardiography were used for evaluating diastolic dysfunction. Information concerning age, systolic blood pressure, height, heart rate, body mass index, total and high-density lipoprotein cholesterol, self-reported use of alcohol, smoking, coffee, physical activity, antihypertensive treatment, prevalent coronary heart disease, valvular heart disease, heart failure, hypertrophy, diabetes and palpitations were obtained at baseline. The outcome measure was clinical AF, documented by an ECG.

Results

AF was detected in 462 subjects (193 women). Mean age at baseline was 62.6 years. Incidence rate of clinical AF was 12.6 per 1000 person-years. In multivariable Cox proportional hazards regression analysis, moderately enlarged LA was associated with 60% (95% CI 1.2 to 2.0) increased risk of AF. Severely enlarged LA had HR for AF of 4.2 (95% CI 2.7 to 6.5) with p value for linear trend <0.001, and the association was similar in both sexes. Abnormal mitral Doppler flow adjusted for predictor variables did not show a statistically significant association with AF risk. However, when LA size was also adjusted for, the risk of AF increased by 30% (95% CI 1.0 to 1.6).

Conclusions

Our findings suggest that enlarged LA as a measure for diastolic dysfunction is a significant risk factor for AF in both sexes, and adding measures of abnormal diastolic flow increased the predictive ability significantly.

Cardiopulmonary resuscitation; use, training and self-confidence in skills. A self-report study among hospital personnel

BACKGROUND

Immediate start of basic cardiopulmonary resuscitation (CPR) and early defibrillation have been highlighted as crucial for survival from cardiac arrest, but despite new knowledge, new technology and massive personnel training the survival rates from in-hospital cardiac arrest are still low. National guidelines recommend regular intervals of CPR training to make all hospital personnel able to perform basic CPR till advanced care is available. This study investigates CPR training, resuscitation experience and self-confidence in skills among hospital personnel outside critical care areas.

METHODS

A cross-sectional study was performed at three Norwegian hospitals. Data on CPR training and CPR use were collected by self-reports from 361 hospital personnel.

RESULTS

A total of 89% reported training in CPR, but only 11% had updated their skills in accordance with the time interval recommended by national guidelines. Real resuscitation experience was reported by one third of the respondents. Both training intervals and use of skills in resuscitation situations differed among the professions. Self-reported confidence decreased only after more than two years since last CPR training.

CONCLUSION

There is a gap between recommendations and reality in CPR training among hospital personnel working outside critical care areas.