Changes in Physical Activity and Incidence of Nonfatal Cardiovascular Events in 47 153 Survivors of Myocardial Infarction

Background The majority of patients survive the acute phase of myocardial infarction (MI) but have an increased risk of recurrent cardiovascular disease (CVD) events. To be regularly physically active or change activity level is associated with a lower risk of all-cause mortality. The objective was to explore to what extent physical activity (PA) levels or change in PA levels during the first year post-MI was associated with any recurrent nonfatal CVD events and specific CVD events (eg, MI, ischemic stroke, and vascular dementia). Methods and Results This cohort study among MI survivors was based on Swedish national registries between 2005 and 2020. PA levels were self-rated at 2 and 12 months post-MI, and patients were classified into remaining physically inactive, increasing, decreasing, or remaining active. A total of 6534 nonfatal CVD events occurred during 6 years of follow-up among the 47 153 included patients. In fully adjusted analyses, the risk of any nonfatal CVD event was lower (P<0.05) among patients remaining active (37%), increasing (22%), or decreasing (18%) PA level compared with remaining inactive. Compared with remaining inactive, the risk of recurring MI and stroke was lower (P>0.05) among remaining active (41% versus 52%, respectively), increasing (20% versus 35%, respectively), or decreasing PA level (24% versus 34%, respectively). For vascular dementia, patients remaining physically active had an 80% lower risk compared with remaining inactive (P<0.05). Conclusions Remaining physically active or change in PA levels during the first year post-MI was associated with a lower risk of recurrent nonfatal CVD events. This emphasizes the importance of supporting patients to continue to be or become physically active.

Lifestyle-related habits and factors before and after cardiovascular diagnosis: a case control study among 2,548 Swedish individuals

BACKGROUND

Healthy lifestyle habits are recommended in prevention of cardiovascular disease (CVD). However, there is limited knowledge concerning the change in lifestyle-related factors from before to after a CVD event. Thus, this study aimed to explore if and how lifestyle habits and other lifestyle-related factors changed between two health assessments in individuals experiencing a CVD event between the assessments, and if changes varied between subgroups of sex, age, educational level, duration from CVD event to second assessment and type of CVD event.

METHODS

Among 115,504 Swedish employees with data from two assessments of occupational health screenings between 1992 and 2020, a total of 637 individuals (74% men, mean age 47 ± SD 9 years) were identified having had a CVD event (ischemic heart disease, cardiac arrythmia or stroke) between the assessments. Cases were matched with controls without an event between assessments from the same database (ratio 1:3, matching with replacement) by sex, age, and time between assessment (n = 1911 controls). Lifestyle habits included smoking, active commuting, exercise, diet, alcohol intake, and were self-rated. Lifestyle-related factors included overall stress, overall health (both self-rated), physical capacity (estimated by submaximal cycling), body mass index and resting blood pressure. Differences in lifestyle habits and lifestyle-related factors between cases and controls, and changes over time, were analysed with parametric and non-parametric tests. Multiple logistic regression, OR (95% CI) was used to analyse differences in change between subgroups.

RESULTS

Cases had, in general, a higher prevalence of unhealthy lifestyle habits as well as negative life-style related factors prior to the event compared to controls. Nevertheless, cases improved their lifestyle habits and lifestyle factors to a higher degree than controls, especially their amount of active commuting (p = 0.025), exercise (p = 0.009) and non-smoking (p < 0.001). However, BMI and overall health deteriorated to a greater extent (p < 0.001) among cases, while physical capacity (p < 0.001) decreased in both groups.

CONCLUSION

The results indicate that a CVD event may increase motivation to improve lifestyle habits. Nonetheless, the prevalence of unhealthy lifestyle habits was still high, emphasizing the need to improve implementation of primary and secondary CVD prevention.

Convergent validity of commonly used questions assessing physical activity and sedentary time in Swedish patients after myocardial infarction

BACKGROUND

Guidelines recommend regular physical activity (PA) and decreased sedentary time (SED) for patients after myocardial infarction (MI). Therefore, valid self-assessment of PA is vital in clinical practice. The purpose of this study was to assess the convergent validity of commonly used PA and SED questions recommended by the National Board of Health and welfare (NBHW) and national SWEDEHEART-registry using accelerometers as the reference method in patients after MI.

METHODS

Data were obtained 2017-2021 among Swedish men and women (180 assessments). Participants answered five commonly used PA and SED-questions (by NBHW and SWEDEHEART) and wore an accelerometer (Actigraph GT3X) for seven days. Convergent validity was assessed gradually by; Kruskall Wallis-, Sperman rho, Weighted Kappa- and ROC-analyses. Misclassification was explored by Chi-square analyses with Benjamini-Hochberg adjustment.

RESULTS

The strongest correlation (r = 0.37) was found for the SED-GIH question (NBHW). For PA, no specific question stood out, with correlations of r = 0.31 (NBWH), and r = 0.24-0.30 (SWEDEHEART). For all questions (NBHW and SWEDEHEART), there was a high degree of misclassification (congruency 12-30%) affecting the agreement (0.09-0.32) between self-report and accelerometer assessed time. The SED-GIH, PA-index and SWEDEHEART-VPA had the strongest sensitivity for identifying individuals with high SED (0.72) or low PA (0.77 and 0.75).

CONCLUSION

The studied PA and SED questions may provide an indication of PA and SED level among patients with MI in clinical practice and could be used to form a basis for further dialogue and assessment. Further development is needed, since practical assessment tools of PA and SED are desirable.

Cardiorespiratory fitness and lifestyle on severe COVID-19 risk in 279,455 adults: a case control study

Background

The impact of cardiorespiratory fitness (CRF) and other lifestyle-related factors on severe COVID-19 risk is understudied. The present study aims to investigate lifestyle-related and socioeconomic factors as possible predictors of COVID-19, with special focus on CRF, and to further study whether these factors may attenuate obesity- and hypertension-related risks, as well as mediate associations between socioeconomic factors and severe COVID-19 risk.

Methods

Out of initially 407,131 participants who participated in nationwide occupational health service screening between 1992 and 2020, n = 857 cases (70% men, mean age 49.9 years) of severe COVID-19 were identified. CRF was estimated using a sub-maximum cycle test, and other lifestyle variables were self-reported. Analyses were performed including both unmatched, n = 278,598, and sex-and age-matched, n = 3426, controls. Severe COVID-19 included hospitalization, intensive care or death due to COVID-19.

Results

Patients with more severe COVID-19 had significantly lower CRF, higher BMI, a greater presence of comorbidities and were more often daily smokers. In matched analyses, there was a graded decrease in odds for severe COVID-19 with each ml in CRF (OR = 0.98, 95% CI 0.970 to 0.998), and a two-fold increase in odds between the lowest and highest (< 32 vs. ≥ 46 ml·min⁻¹·kg⁻¹) CRF group. Higher BMI (per unit increase, OR = 1.09, 1.06 to 1.12), larger waist circumference (per cm, OR = 1.04, 1.02 to 1.06), daily smoking (OR = 0.60, 0.41 to 0.89) and high overall stress (OR = 1.36, 1.001 to 1.84) also remained significantly associated with severe COVID-19 risk. Obesity- and blood pressure-related risks were attenuated by adjustment for CRF and lifestyle variables. Mediation through CRF, BMI and smoking accounted for 9% to 54% of the associations between low education, low income and blue collar/low skilled occupations and severe COVID-19 risk. The results were consistent using either matched or unmatched controls.

Conclusions

Both lifestyle-related and socioeconomic factors were associated with risk of severe COVID-19. However, higher CRF attenuated the risk associated with obesity and high blood pressure, and mediated the risk associated with various socioeconomic factors. This emphasises the importance of interventions to maintain or increase CRF in the general population to strengthen the resilience to severe COVID-19, especially in high-risk individuals.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-021-01198-5.

Participation in exercise-based cardiac rehabilitation is related to reduced total mortality in both men and women: results from the SWEDEHEART registry

AIMS

Participation in exercise-based cardiac rehabilitation (exCR) increases aerobic capacity and improves outcomes in patients following myocardial infarction (MI) and is therefore universally recommended. While meta-analyses consistently report that participation in exCR reduces cardiovascular mortality, there are conflicting results regarding effects on total mortality. Presently, many eligible patients do not receive exCR in clinical practice. We aimed to investigate the relation between participation in exCR post-MI and total mortality in men and women in a nationwide real-world cohort from the SWEDEHEART registry.

DESIGN

Longitudinal, observational cohort study.

METHODS AND RESULTS

In total, 20 895 patients from the SWEDEHEART registry were included. Mortality data were obtained from the Swedish National Population Registry. During a mean of 4.55 (±2.33) years of follow-up, 1000 patients died. Using Cox regression for proportional odds and taking a wide range of potential confounders into consideration, participation in exCR was related to significantly lower total mortality [hazard ratio (HR) 0.72, 95% confidence interval 0.62-0.83]. Excluding patients with shorter follow-up than 2 years did not alter the results. Exercise-based CR participation was related to lowered total mortality in most of the investigated subgroups. The risk reduction was more pronounced in women than in men (HR 0.54 vs. 0.81, respectively).

CONCLUSION

Participation in exCR was associated with reduced total mortality, and more pronounced in women, compared with men. Our results further support the recommendations to participate in exCR, and hence we argue that exCR should be a mandatory part of comprehensive CR programmes, offered to all patients post-MI.

Lifestyle Habits and Mental Health in Light of the Two COVID-19 Pandemic Waves in Sweden, 2020

The COVID-19 pandemic has become a public health emergency of international concern, which may have affected lifestyle habits and mental health. Based on national health profile assessments, this study investigated perceived changes of lifestyle habits in response to the COVID-19 pandemic and associations between perceived lifestyle changes and mental health in Swedish working adults. Among 5599 individuals (50% women, 46.3 years), the majority reported no change (sitting 77%, daily physical activity 71%, exercise 69%, diet 87%, alcohol 90%, and smoking 97%) due to the pandemic. Changes were more pronounced during the first wave (April–June) compared to the second (October–December). Women, individuals <60 years, those with a university degree, white-collar workers, and those with unhealthy lifestyle habits at baseline had higher odds of changing lifestyle habits compared to their counterparts. Negative changes in lifestyle habits and more time in a mentally passive state sitting at home were associated with higher odds of mental ill-health (including health anxiety regarding one’s own and relatives’ health, generalized anxiety and depression symptoms, and concerns regarding employment and economy). The results emphasize the need to support healthy lifestyle habits to strengthen the resilience in vulnerable groups of individuals to future viral pandemics and prevent health inequalities in society.

High affinity binding of 7-aminoactinomycin D and 4',6-diamidino-2-phenylindole to human neutrophilic granulocytes and lymphocytes

The binding behavior of the DNA binding dyes 7-aminoactinomycin D (7-AAMD) and 4',6-diamidino-2-phenylindole (DAPI) to human neutrophilic granulocytes and lymphocytes was studied by image cytofluorometry. Peripheral blood leukocytes were prefixed in paraformaldehyde (PFA) and attached to cover glasses. Different fixation, permeabilization, and acid extraction method were applied before the cells were stained to equilibrium using varying concentrations of 7-AAMD or DAPI. The apparent association constant and number of high affinity dye binding sites were estimated for the different cell types, dyes, and treatments. Acid-extracted cells, supposedly containing nucleosome-free DNA, were chosen to represent maximal dye binding. Only about 10% of the 7-AAMD binding sites remained in the unextracted PFA-fixed cells, and the apparent dye affinity was also reduced. We found no major difference in high affinity binding between the cell types, but granulocytes showed more fluorescence from less specifically bound 7-AAMD compared to lymphocytes. DAPI had a much higher affinity than 7-AAMD, independent of the preparation method. It showed a cooperative binding behavior with an apparent saturation of the high affinity binding sites at a dye concentration of about 50 nM. We conclude that both dyes may be useful as probes for chromatin structure in intact cells and that our new technique may contribute to such studies since it allows determination of dye affinities and numbers of high affinity binding sites in situ.

Transforming growth factor (TGF beta) decreases the proliferation of human bone marrow fibroblasts by inhibiting the platelet-derived growth factor (PDGF) binding

Human bone marrow fibroblasts were cultivated and characterized by immunofluorescent staining and electron microscopy. Their interactions with PDGF and TGF beta were studied. While a positive intracellular antifibronectin staining was observed, the cultured cells were not labeled with specific antibodies toward factor VIII von Willebrand factor (F VIII/vWF), desmin, and macrophage antigen. Moreover, electron microscopy excluded the presence of endothelial cells by the absence of Weibel-Palade bodies. The binding of pure human PDGF to the cultured bone marrow fibroblasts was investigated. Addition of an excess of unlabeled PDGF decreased the binding to 75 and 80%, which means that the nonspecific binding represented 20-25% of total binding, whereas epidermal growth factor (EGF) had no effect. Two classes of sites were detected by Scatchard analysis with respectively 21,000 and 37,000 sites per cell, with a KD of 0.3 x 10(-10) M and KD of 0.5 x 10(-9) M. The stimulation of DNA synthesis by PDGF was quantified by [3H]thymidine incorporation. When PDGF was added alone at a concentration of 15 ng/ml, it induced a maximal DNA synthesis of 400%, which increased up to 900%, in the presence of platelet-poor plasma (PPP). On the other hand, PDGF-induced fibroblast proliferation was inhibited in a dose-dependent manner by TGF beta. This inhibition was related to a significantly decreased binding of 125I-labeled PDGF observed in the presence of TGF beta. Our results suggested that PDGF and TGF beta could modulate the growth of bone marrow fibroblasts.