Cardiovascular disease risk and all-cause mortality associated with accelerometer-measured physical activity and sedentary time ‒ a prospective population-based study in older adults.

BACKGROUND: Low levels of physical activity (PA) and high sedentary time (ST) are common in older adults and lack of PA is a risk factor for cardiovascular disease (CVD). Knowledge about associations with accelerometer-measured PA, ST and CVD risk in older adults is insufficient. This study examines the associations of accelerometer-measured PA and ST with cardiovascular risk measured using the Framingham risk score (FRS) and all-cause mortality in older adults. METHODS: A population-based sample of 660 (277 men, 383 women) older people (mean age 68.9) participated in the Oulu45 cohort study from 2013‒2015. PA and ST were measured with wrist-worn accelerometers at baseline for two weeks. Ten-year CVD risk (%) was estimated with FRS. The data for all-cause mortality were identified from the Digital and Population Data Services Agency, Finland after an average of 6.2 years follow-up. The associations between moderate to vigorous physical activity (MVPA), light physical activity (LPA), ST and FRS were analyzed using the multivariable linear regression analysis. Associations between LPA, ST and mortality were analyzed using the Cox proportional-hazard regression models. RESULTS: Each 10 min increase in MVPA (ß = -0.779, 95% CI -1.186 to -0.371, p < 0.001) and LPA (ß = -0.293, 95% CI -0.448 to -0.138, p < 0.001) was negatively associated with FRS while a 10 min increase in ST (ß = 0.290, 95% CI 0.158 to 0.421, p < 0.001) was positively associated with FRS. After adjustment for waist circumference, only ST was significantly associated with FRS. Each 10 min increase in LPA was associated with 6.5% lower all-cause mortality risk (HR = 0.935, 95% CI 0.884 to 0.990, p = 0.020) and each 10 min increase in ST with 5.6% increased mortality risk (HR = 1.056, 95% CI 1.007 to 1.108, p = 0.025). CONCLUSION: A higher amount of daily physical activity, at any intensity level, and avoidance of sedentary time are associated with reduced cardiovascular disease risk in older people. Higher time spent in light physical activity and lower sedentary time are associated with lower all-cause mortality.

Good safety practice in a randomized controlled trial (CadColdEx) involving increased cardiac workload in patients with coronary artery disease.

BACKGROUND: Methodological information acknowledging safety of cardiac patients in controlled medical experiments are lacking. The descriptive report presents one good practice for considering safety in a randomized controlled study involving augmented cardiovascular strain among persons with coronary artery disease (CAD). METHODS: The patients were pre-selected by a cardiologist according to strictly defined selection criteria. Further confirmation of eligibility included screening of health. In addition, assessments of physical capacity by a graded bicycle ergometer test were implemented and safety monitored by an exercise physiologist and medical doctor. In this context, an emergency simulation was also carried out. A total of 18 CAD patients each underwent four different experimental interventions where either temperature (+ 22 °C and - 15 °C) and the level of exercise (rest and brisk walking) were employed for 30 min in random order (72 experiments). Baseline (20 min) and follow-up (60 min) measurements were conducted resting at + 22 °C. ECG, and brachial blood pressure were measured and perceived exertion and symptoms of chest pain inquired throughout the experiments. An emergency nurse was responsible for the health monitoring and at least two persons followed the patient throughout the experiment. A medical doctor was available on call for consultation. The termination criteria followed the generally accepted international guidelines for exercise testing and were planned prior to the experiments. RESULTS: The exercise test simulation revealed risks requiring changes in the study design and emergency response. The cardiovascular responses of the controlled trials were related to irregular HR, ST-depression or post-exercise hypotension. These were expected and the majority could be dealt on site by the research personnel and on call consultation. Only one patient was encouraged to seek for external health care consultation. CONCLUSIONS: Appropriate prospective design is a key to safe implementation of controlled studies involving cardiac patients and stimulation of cardiovascular function. This includes careful selection of participants, sufficient and knowledgeable staff, as well as identifying possible emergency situations and the required responses. TRIAL REGISTRATION: ClinicalTrials ID: NCT02855905 .

Association between accelerometer-measured physical activity, glucose metabolism, and waist circumference in older adults.

AIMS: To examine the association of physical activity (PA) and sedentary time (ST) with glucose metabolism according to waist circumference (WC) in older people. METHODS: A population-based sample of 702 individuals (aged 67-70 years) wore wrist-worn accelerometers for two weeks and underwent an oral glucose tolerance test. The associations between moderate-to-vigorous (MVPA) and light (LPA) PA, ST, and glucose metabolism across the tertiles of WC were analysed using general linear regression. RESULTS: Among highest WC tertile, LPA negatively associated with fasting insulin (ß =  - 0.047, 95% CI - 0.082 to - 0.012), HOMA-IR (ß =  - 0.098, 95% CI - 0.184 to - 0.012), and HOMA-ß (ß =  - 3.367, CI - 6.570 to - 0.783). ST associated with 120 min glucose (ß = 0.140, CI 0.021 to 0.260). Among lowest WC tertile, MVPA negatively associated with 30 min insulin (ß =  - 0.086, 95% CI - 0.168 to - 0.004) and 120 min insulin (ß =  - 0.160, 95% CI - 0.257 to - 0.063) and positively associated with Matsuda index (ß = 0.076, 95% CI 0.014 to 0.139). Light PA negatively associated with 120 min insulin (ß =  - 0.054, 95% CI - 0.104 to - 0.005). CONCLUSION: With the limitation of the cross-sectional study, reducing ST and increasing LPA may be beneficial for glucose metabolism among abdominally obese older adults. Lean older adults could benefit more from increasing MVPA.