Predictors of secondary cardiovascular events

Cardiovascular diseases (CVD) are the number one cause of death worldwide. About one fifth of those who survived a myocardial infarction will suffer a recurrent cardiovascular event (CVE). Given the low participation in recommended cardiac rehabilitation, there is interest in early risk stratification after a primary CVE. This dissertation evaluates leisure time physical activity (LTPA), N-Terminal pro-Brain Natriuretic Peptide (NT-proBNP) and cystatin C as predictors of a secondary CVE in a German cohort of cardiac rehabilitation patients with stable coronary heart disease followed from 1999 to 2008. Study 1 evaluated self-reported LTPA at one-year follow-up. Those reporting seldom/never practice of LTPA showed a higher risk (Hazard Ratio (HR) 1.30 [95% Confidence Interval (CI) 0.62, 2.69]), while those reporting LTPA at least 5-6 times/week had a reduced risk (HR 0.88 [95% CI 0.54, 1.43]) for a subsequent CVE, when compared to the reference group (1-4 times/month). Study 2 examined LTPA trajectories during the age period 20-49 years. Compared to those with a gradual decline of LTPA, the highest risk was observed among those with a steeper decrease of LTPA (HR 1.59 [95% CI 0.97, 2.62]). A continuous increase of LTPA was associated with a risk reduction (HR 0.71 [95% CI 0.41, 1.22]) with respect to a recurrent CVE. Studies 3 and 4 evaluated the prognostic value of two novel biomarkers, when added to a model containing well-established CVD risk factors. In Study 3, NT-proBNP levels at one-year follow-up and a 10% increase in the slope of a NT-proBNP three-year trajectory were associated with a subsequent CVE ,with HRs of 1.63 [95% CI 1.17, 2.27] and 1.24 [95% CI 1.12, 1.37], respectively. One-year, but not baseline, levels of NT-proBNP showed an improvement in risk reclassification. Study 4 examined cystatin C versus creatinine. Although both were associated with a recurrent CVE, only the addition of cystatin C improved model performance, discrimination and reclassification. In conclusion, in patients with stable coronary heart disease, LTPA, NT-proBNP, and cystatin C might help to identify individuals at high risk for a recurrent CVE. Further research is needed to evaluate treatment modalities for secondary prevention in this group

Addition of Inflammatory Biomarkers Did Not Improve Diabetes Prediction in the Community: The Framingham Heart Study

Background: Prior studies have reported conflicting findings with regard to the association of biomarkers in the prediction of incident type 2 diabetes. We evaluated 12 biomarkers as possible diabetes predictors in the Framingham Heart Study. Methods and results: Biomarkers representing inflammation (C-reactive protein, interleukin-6, monocyte chemoattractant protein-1, tumor necrosis factor receptor 2, osteoprotegerin, and fibrinogen), endothelial dysfunction (intercellular adhesion molecule-1), vascular damage (CD40-ligand, P-selectin, and lipoprotein-associated phospholipase A2 mass and activity), and oxidative stress (urinary isoprostanes) were measured in participants without diabetes attending the Offspring seventh (n=2499) or multiethnic Omni second (n=189) examination (1998–2001). Biomarkers were loge transformed and standardized. Multivariable logistic regression tested each biomarker in association with incident diabetes at a follow-up examination (the Offspring eighth and Omni third examination; mean 6.6 years later), with adjustment for age, sex, cohort, body mass index, fasting glucose, systolic blood pressure, high-density lipoprotein cholesterol, triglycerides, and smoking. C statistics were evaluated with and without inflammatory markers. In 2638 participants (56% women, mean age 59 years), 162 (6.1%) developed type 2 diabetes. All biomarkers, excluding osteoprotegerin, were associated with the outcome with adjustment for age, sex, and cohort; however, none remained significant after multivariable adjustment (all P>0.05). The c statistic from the model including only clinical covariates (0.89) did not statistically significantly improve after addition of biomarkers (all P>0.10). Conclusions: Biomarkers representing different inflammatory pathways are associated with incident diabetes but do not remain statistically significant after adjustment for established clinical covariates. Inflammatory biomarkers might not be an effective resource to predict type 2 diabetes in community-based samples

Associations of sedentary behavior bouts with community-dwelling older adults' physical function

The study aim was to explore associations between sedentary behavior (SB) bouts and physical function in 1360 community-dwelling older adults (≥65 years old). SB was measured using an ActiGraph wGT3X + accelerometer for seven consecutive days at the dominant hip and processed accordingly. Various SB bout lengths were assessed including: 1- to 9-minutes; 10- to 29-minutes; 30- to 59-minutes; and ≥60-minutes, as well as maximum time spent in a SB bout. Total SB time was adjusted for within the SB bout variables used (percentage SB time in the SB bout length and number of SB bouts per total SB hour). Physical function was assessed using the 2-minute walk test (2MWT), 5-times sit-to-stand (chair stand) test, and unipedal stance test (UST). Hierarchical linear regression models were utilized. Covariates such as moderate-vigorous physical activity (MVPA), demographic and health characteristics were controlled for. Lower percentage time spent in ≥60-minute SB bouts was significantly (P <.05) associated with longer 2MWT distance while lower numbers of ≥60-minute SB bouts were associated with longer 2MWT distance, shorter chair stand time and longer UST time. There were mixed associations with physical function for 10- to 29-minute SB bouts. In a large cohort of European older adults, prolonged SB bouts lasting ≥60-minutes appear to be associated with reduced physical function after controlling for MVPA and numerous other important covariates. Besides reducing SB levels, these findings suggest there is a need to regularly interrupt prolonged SB to improve physical function in older adults

The Association of Physical Activity Fragmentation with Physical Function in Older Adults: Analysis from the SITLESS Study

The distribution of physical activity bouts through the day may provide useful information for assessing the impacts of interventions on aspects such as physical function. This study aimed to investigate the associations between physical activity fragmentation, tested using different minimum physical activity bout lengths, with physical function in older adults. The SITLESS project recruited 1360 community-dwelling participants from four European countries (≥65 years old). Physical activity fragmentation was represented as the active-to-sedentary transition probability (ASTP), the reciprocal of the average physical activity bout duration measured using ActiGraph wGT3X+ accelerometers. Four minimum bout lengths were utilised to calculate the ASTP: ≥10-s, ≥60-s, ≥120-s and ≥300-s. Physical function was assessed using the 2-min walk test (2MWT) and the composite score from the Short Physical Performance Battery (SPPB) test. Linear regression analyses, after adjusting for relevant covariates, were used to assess cross-sectional associations. After adjustment for relevant covariates, lower ASTP using ≥10-s bouts were associated with longer 2MWT distances and higher SPPB scores. Lower ASTP using ≥120-s bouts and ≥300-s bouts were associated with longer 2MWT distances but not the SPPB. Less fragmented physical activity patterns appeared to be associated with better physical function in community-dwelling older adult

A proposal for the retrospective identification and categorization of older people with functional impairments in scientific studies : recommendations of the Medication and Quality of Life in Frail Older Persons (MedQoL) research group

When treating older adults, a main factor to consider is physical frailty. Because specific assessments in clinical trials are frequently lacking, critical appraisal of treatment evidence with respect to functional status is challenging. Our aim was to identify and categorize assessments for functional status given in clinical trials in older adults to allow for a retrospective characterization and indirect comparison of treatment evidence from these cohorts. We conducted 4 separate systematic reviews of randomized and nonrandomized controlled clinical trials in older people with hypertension, diabetes, depression, and dementia. All assessments identified that reflected functional status were analyzed. Assessments were categorized across 4 different functional status levels. These levels span from functionally not impaired, slightly impaired, significantly impaired, to severely impaired/disabled. If available from the literature, cut-offs for these 4 functioning levels were extracted. If not, or if the existing cut-offs did not match the predefined functional levels, cut-off points were defined by an expert group composed of geriatricians, pharmacists, pharmacologists, neurologists, psychiatrists, and epidemiologists using a patient-centered approach. We identified 51 instruments that included measures of functional status. Although some of the assessments had clearly defined cut-offs across our predefined categories, many others did not. In most cases, no cut-offs existed for slightly impaired or severely impaired older adults. Missing cut-offs or values to adjust were determined by the expert group and are presented as described. The functional status assessments that were identified and operationalized across 4 functional levels could now be used for a retrospective characterization of functional status in randomized controlled trials and observational studies. Allocated categories only serve as approximations and should be validated head-to-head in future studies. Moreover, as general standard, upcoming studies involving older adults should include and explicitly report functional impairment as a baseline characteristic of all participants enrolled

The effectiveness and complexity of interventions targeting sedentary behaviour across the lifespan: a systematic review and meta-analysis

Background: Evidence suggests that sedentary behaviour (SB) is associated with poor health outcomes. SB at any age may have significant consequences for health and well-being and interventions targeting SB are accumulating. Therefore, the need to review the effects of multicomponent, complex interventions that incorporate effective strategies to reduce SB are essential. Methods: A systematic review and meta-analysis were conducted investigating the impact of interventions targeting SB across the lifespan. Six databases were searched and two review authors independently screened studies for eligibility, completed data extraction and assessed the risk of bias and complexity of each of the included studies. Results: A total of 77 adult studies (n=62, RCTs) and 84 studies (n=62, RCTs) in children were included. The findings demonstrated that interventions in adults when compared to active controls resulted in non-significant reductions in SB, although when compared to inactive controls significant reductions were found in both the short (MD -56.86; 95%CI -74.10, -39.63; n=4632; I2 83%) and medium-to-long term (MD -20.14; 95%CI -34.13, -6.16; n=4537; I2 65%). The findings demonstrated that interventions in children when compared to active controls may lead to relevant reductions in daily sedentary time in the short-term (MD -59.90; 95%CI -102.16, -17.65; n=267; I2 86%), while interventions in children when compared to inactive controls may lead to relevant reductions in the short-term (MD -25.86; 95%CI -40.77, -10.96; n=9480; I2 98%) and medium-to-long term (MD -14.02; 95%CI -19.49, -8.55; n=41,138; I2 98%). The assessment of complexity suggested that interventions may need to be suitably complex to address the challenges of a complex behaviour such as SB, but demonstrated that a higher complexity score is not necessarily associated with better outcomes in terms of sustained long-term changes. Conclusions: Interventions targeting reductions in SB have been shown to be successful, especially environmental interventions in both children and adults. More needs to be known about how best to optimise intervention effects. Future intervention studies should apply more rigorous methods to improve research quality, considering larger sample sizes, randomised controlled designs and valid and reliable measures of SB

Cost-effectiveness of a programme to address sedentary behaviour in older adults: results from the SITLESS RCT

Background: This study details the within-trial economic evaluation and long-term economic model of SITLESS, a multi-country, three-armed randomized controlled trial comparing a combined intervention of exercise referral schemes (ERS) enhanced by self-management strategies (SMS) against ERS alone and usual care (UC). Methods: A cost-utility analysis, conducted from the base-case perspective of the National Health Service and personal and social services, estimated the incremental cost per incremental quality-adjusted life year (QALY) and years in full capability (YFC). A secondary analysis combined the costs with a broad set of outcomes within a cost-consequence framework, from a societal perspective. A Markov-type decision-analytic model was developed to project short-term changes in physical activity to long-term outcomes and costs, over a 5- and 15-year time horizon. Results: The results of the within-trial analysis show that SMS+ERS is highly likely to be cost-effective compared to ERS alone (ICER €4270/QALY), but not compared to UC. Participants allocated to the SMS+ERS group also showed an improvement in YFC compared to ERS alone and UC. The long-term analysis revealed that SMS+ERS is likely to be a cost-effective option compared to ERS and UC over a 5-year, but not with a 15-year horizon, being then dominated by ERS alone. Conclusion: This research provides new evidence that SMS is a cost-effective add-on to ERS strategies. This economic evaluation informs the case for further, cost-effective, refinement of lifestyle change programmes targeted to older adults, with the aim of ultimately reducing the impact of non-communicable diseases in this population

What works to prevent falls in older adults dwelling in long term care facilities and hospitals? An umbrella review of meta-analyses of randomised controlled trials

Preventing falls in long term care facilities (LTCF) and hospitals is an international priority. Many interventions have been investigated and summarised in meta-analyses (MA) and there is a need to synthesise the top of the hierarchy of evidence in one place. Therefore we conducted an umbrella review of MA of randomised controlled trials (RCTs) of falls prevention interventions LTCF and hospitals. Two independent reviewers searched major electronic databases from inception till October 2014 for MA containing ≥3 RCTs investigating any intervention to prevent falls in LTCF or hospitals in older adults aged ≥60 years. Methodological quality was assessed by the AMSTAR tool and data were narratively synthesised. The methodological quality of the MA was moderate to high across the 10 included MA. Nine MA provided data for LTCF and only two considered hospital settings. Only one MA defined a fall and two reported adverse events (although minor). Consistent evidence suggests that multifactorial interventions reduce falls (including the rate, risk and odds of falling) in LTCF and hospitals. Inconsistent evidence exists for exercise and vitamin D as single interventions in LTCF, whilst no MA has investigated this in hospitals. No evidence exists for hip protectors and medication review on falls in LTCF. In conclusion, multifactorial interventions appear to be the most effective interventions to prevent falls in LTCF and hospital settings. This is not without limitations and more high quality RCTs are needed in hospital settings in particular. Future RCTs and MA should clearly report adverse events