Prediction of sustained harmonic walking in the free-living environment using raw accelerometry data

Objective. Using raw, sub-second level, accelerometry data, we propose and validate a method for identifying and characterizing walking in the free-living environment. We focus on the sustained harmonic walking (SHW), which we define as walking for at least 10 seconds with low variability of step frequency. Approach. We utilize the harmonic nature of SHW and quantify local periodicity of the tri-axial raw accelerometry data. We also estimate fundamental frequency of observed signals and link it to the instantaneous walking (step-to-step) frequency (IWF). Next, we report total time spent in SHW, number and durations of SHW bouts, time of the day when SHW occurred and IWF for 49 healthy, elderly individuals. Main results. Sensitivity of the proposed classification method was found to be 97%, while specificity ranged between 87% and 97% and prediction accuracy between 94% and 97%. We report total time in SHW between 140 and 10 minutes-per-day distributed between 340 and 50 bouts. We estimate the average IWF to be 1.7 steps-per-second. Significance. We propose a simple approach for detection of SHW and estimation of IWF, based on Fourier decomposition. The resulting approach is fast and allows processing of a week-long raw accelerometry data (approx. 150 million measurements) in relatively short time (~half an hour) on a common laptop computer (2.8 GHz Intel Core i7, 16 GB DDR3 RAM)

Transformation and integration of heterogeneous health data in a privacy-preserving distributed learning infrastructure

Problem statement: A growing volume and variety of personal health data are being collected by different entities, such as healthcare providers, insurance companies, and wearable device manufacturers. Combining heterogeneous health data offers unprecedented opportunities to augment our understanding of human health and disease. However, a major challenge to research lies in the difficulty of accessing and analyzing health data that are dispersed in their format (e.g. CSV, XML), sources (e.g., medical records, laboratory data), representation (unstructured, structured), and governance (e.g., data collection and maintenance)[2]. Such considerations are crucial when we link and use personal health data across multiple legal entities with different data governance and privacy concerns

PREDICTING HUMAN MOVEMENT TYPE BASED ON MULTIPLE ACCELEROMETERS USING MOVELETS

We introduce statistical methods for prediction of types of human movement based on three tri-axial accelerometers worn simultaneously at the hip, left, and right wrist. We compare the individual performance of the three accelerometers using movelets and propose a new prediction algorithm that integrates the information from all three accelerometers. The development is motivated by a study of 20 older subjects who were instructed to perform 15 different types of activities during in-laboratory sessions. The differences in the prediction performance for different activity types among the three accelerometers reveal subtle yet important insights into how the intrinsic physical features of human movements could be effectively utilized in prediction. The proposed integrative movelet method takes into account those findings to augment the prediction accuracy and improve our understanding of human movement measurements

The association of early life socioeconomic conditions with prediabetes and type 2 diabetes: results from the Maastricht study

markdownabstractBackground: Using cross-sectional data from The Maastricht Study, we examined the association of socioeconomic conditions in early life with prediabetes and T2DM in adulthood. We also examined potential mediating pathways via both adulthood socioeconomic conditions and adult BMI and health behaviours. Methods: Of the 3263 participants (aged 40-75 years), 493 had prediabetes and 906 were diagnosed with T2DM. By using logistic regression analyses, the associations and possible mediating pathways were examined. Results: Participants with low early life socioeconomic conditions had a 1.56 times higher odds of prediabetes (95% confidence interval (CI) = 1.21-2.02) and a 1.61 times higher odds of T2DM (95% CI = 1.31-1.99). The relation between low early life socioeconomic conditions and prediabetes was independent of current socioeconomic conditions (OR = 1.38, 95% CI = 1.05-1.80), whereas the relation with T2DM was not independent of current socioeconomic conditions (OR = 1.10, 95% CI = 0.87-1.37). BMI party mediated the association between early life socioeconomic conditions and prediabetes. Conclusions: Socioeconomic inequalities starting in early life were associated with diabetes-related outcomes in adulthood and suggest the usefulness of early life interventions aimed at tackling these inequalities

Blood pressure variability in individuals with and without (pre)diabetes:the Maastricht Study

Objective: The mechanisms associating (pre)diabetes and cardiovascular disease (CVD) are incompletely understood. We hypothesize that greater blood pressure variability (BPV) may underlie this association, due to its association with (incident) CVD. Therefore, we investigated the association between (pre)diabetes and very short-term to mid-term BPV, that is within-visit, 24-h and 7-day BPV. Methods: Cross-sectional data from The Maastricht Study [normal glucose metabolism (NGM), n¼1924; prediabetes, n¼511; type 2 diabetes mellitus (T2DM), n¼975; 51% men, aged 608 years]. We determined SD for within visit BPV (n¼3244), average real variability for 24-h BPV (n¼2699) day (0900–2100 h) and night (0100–0600 h) separately, and SD for 7-day BPV (n¼2259). Differences in BPV as compared with NGM were assessed by multiple linear regressions with adjustment for potential confounders. Results: In T2DM, the average systolic/diastolic values of within-visit, 24-h and 7-day BPV were 4.8/2.6, 10.5/7.3 and 10.4/6.5 mmHg, respectively, and in prediabetes 4.9/ 2.6, 10.3/7.0 and 9.4/5.9 mmHg, respectively. T2DM was associated with greater nocturnal systolic BPV [0.42mmHg (95% confidence interval: 0.05–0.80)], and greater 7-day systolic [0.76mmHg (0.32–1.19)] and diastolic BPV [0.65mmHg (0.29–1.01)], whereas prediabetes was associated with greater within-visit systolic BPV only [0.35mmHg (0.06–0.65)], as compared with NGM. Conclusion: Both T2DM and prediabetes are associated with slightly greater very short-term to mid-term BPV, which may, according to previous literature, explain a small part of the increased CVD risk seen in (pre)diabetes. Nevertheless, these findings do not detract from the fact that very short-term to mid-term BPV is substantial and important in individuals with and without (pre)diabetes

Daily physical activity patterns and their association with health-related physical fitness among aging workers - the Finnish Retirement and Aging study

Background: This study aimed to identify accelerometer measured daily physical activity patterns, and to examine how they associate with health-related physical fitness among aging workers.Methods: The study population consisted of 263 participants (mean age 62.4 years, SD 1.0) from the Finnish Retirement and Aging Study, who used wrist-worn ActiGraph accelerometer for at least one week including both workdays and days off. Health-related physical fitness measures included body composition (waist circumference, bioimpedance), cardiorespiratory fitness (CRF) (bicycle ergometer test) and muscular fitness (push-up and chair rise tests).Results: Based on the latent class trajectory analysis, six trajectories were identified for workdays showing variation in activity level on working hours and on evening hours. Moderate activity during working hours and increase of activity level in the evening was associated with the most favorable health-related fitness in comparison to low activity throughout the workday: waist circumference 90.0 cm (95% CI 85.5-94.5) vs. 99.5 cm (95% CI 96.8-102.3), fat mass 13.9 kg (9.3-18.5) vs. 23.8 kg (20.2-27.4), CRF 33.4 ml/kg/min (95% CI 31.4-35.3) vs. 29.1 ml/kg/min (95% CI 27.8-30.3) (adjusted for age, sex, days off activity, smoking and alcohol). For the days off, two different trajectories were identified, but they differed only in terms of level and not by timing of physical activity.Conclusions: A large variation in the workday physical activity patterns was observed among aging workers. Independent of worktime activity, people who were more active in the evenings had more favorable health-related physical fitness than those who were less active throughout the day.</p

Vigorous Intermittent Lifestyle Physical Activity and Cancer Incidence Among Nonexercising Adults: The UK Biobank Accelerometry Study

IMPORTANCE: Vigorous physical activity (VPA) is a time-efficient way to achieve recommended physical activity (PA) for cancer prevention, although structured longer bouts of VPA (via traditional exercise) are unappealing or inaccessible to many individuals. OBJECTIVES: To evaluate the dose-response association of device-measured daily vigorous intermittent lifestyle physical activity (VILPA) with incident cancer, and to estimate the minimal dose required for a risk reduction of 50% of the maximum reduction. DESIGN, SETTING, AND PARTICIPANTS: This was a prospective cohort analysis of 22 398 self-reported nonexercising adults from the UK Biobank accelerometry subsample. Participants were followed up through October 30, 2021 (mortality and hospitalizations), or June 30, 2021 (cancer registrations). EXPOSURES: Daily VILPA of up to 1 and up to 2 minutes, assessed by accelerometers worn on participants' dominant wrist. MAIN OUTCOMES AND MEASURES: Incidence of total cancer and PA-related cancer (a composite outcome of 13 cancer sites associated with low PA levels). Hazard ratios and 95% CIs were estimated using cubic splines adjusted for age, sex, education level, smoking status, alcohol consumption, sleep duration, fruit and vegetable consumption, parental cancer history, light- and moderate-intensity PA, and VPA from bouts of more than 1 or 2 minute(s), as appropriate. RESULTS: The study sample comprised 22 398 participants (mean [SD] age, 62.0 [7.6] years; 10 122 [45.2%] men and 12 276 [54.8%] women; 21 509 [96.0%] White individuals). During a mean (SD) follow-up of 6.7 (1.2) years (149 650 person-years), 2356 total incident cancer events occurred, 1084 owing to PA-related cancer. Almost all (92.3%) of VILPA was accrued in bouts of up to 1 minute. Daily VILPA duration was associated with outcomes in a near-linear manner, with steeper dose-response curves for PA-related cancer than total cancer incidence. Compared with no VILPA, the median daily VILPA duration of bouts up to 1 minute (4.5 minutes per day) was associated with an HR of 0.80 (95% CI, 0.69-0.92) for total cancer and 0.69 (95% CI, 0.55-0.86) for PA-related cancer. The minimal dose was 3.4 minutes per day for total (HR, 0.83; 95% CI, 0.73-0.93) and 3.7 minutes for PA-related (HR, 0.72; 95% CI, 0.59-0.88) cancer incidence. Findings were similar for VILPA bout of up to 2 minutes. CONCLUSIONS AND RELEVANCE: The findings of this prospective cohort study indicate that small amounts of VILPA were associated with lower incident cancer risk. Daily VILPA may be a promising intervention for cancer prevention in populations not able or motivated to exercise in leisure time

Larger First-Trimester Placental Volumetric Parameters Are Associated With Lower Pressure and More Flow-Mediated Vasodilation of the Fetoplacental Vasculature After Delivery

Objective: To explore the correlation between in vivo placental volumetric parameters in the first trimester of pregnancy and ex vivo parameters of fetoplacental vascular function after delivery. Methods: In ten singleton physiological pregnancies, placental volume (PV) and uteroplacental vascular volume (uPVV) were measured offline in three-dimensional ultrasound volumes at 7, 9, and 11 weeks gestational age (GA) using Virtual Organ Analysis and Virtual Reality. Directly postpartum, term placentas were ex vivo dually perfused and pressure in the fetoplacental vasculature was measured to calculate baseline pressure (pressure after a washout period), pressure increase (pressure after a stepwise fetal flow rate increase of 1 mL/min up to 6 mL/min) and flow-mediated vasodilation (FMVD; reduction in inflow hydrostatic pressure on the fetal side at 6 mL/min flow rate). Correlations between in vivo and ex vivo parameters were assessed by Spearman’s correlation coefficients (R). Results: Throu

Association Between Employment Status and Objectively Measured Physical Activity and Sedentary BehaviorThe Maastricht Study

Objective:To examine the association between employment status and physical activity and sedentary behavior.Methods:We included 2045 participants from The Maastricht Study, who used a thigh-worn accelerometer. We compared time spent sedentary, standing, stepping, and higher intensity physical activity between participants with different employment status (non-employed or low-, intermediate- or high-level occupation) with analysis of variance.Results:Participants in low-level occupations were less sedentary and standing and stepping more than those in other occupational categories and non-employed participants. Among the employed, the differences were mostly observed on weekdays, whereas the differences in sedentary time and standing between those in low-level occupations and non-employed participants were evident both on weekdays and weekend days.Conclusions:Those in low-level occupational category were less sedentary and more active than non-employed and those in other occupational categories, especially on weekdays