Validation of ActiReg ® to measure physical activity and energy expenditure against doubly labelled water in obese persons

Physical and mental health in young adults with heart disease - a national survey of Norwegian university students

BACKGROUND

Young adults with heart disease constitute a growing group with the risk of cognitive and physical impairment. The knowledge of their academic performance and mental and physical health is, however, scant. This study aimed to compare young adults with CHDs or arrhythmia with their peers.

METHODS

Information on physical health (Somatic Symptom Scale-8), mental health problems (Hopkins Symptoms Checklist-25), quality of life (Satisfaction With Life Scale), physical activity, and academic performance was collected online in a national cross-sectional survey in Norway among students in higher education (the SHoT2018 study).

RESULTS

Among 50,054 students, 172 (0.34%) reported CHD and 132 (0.26%) arrhythmias. Students reporting arrhythmias scored significantly higher than the control group on somatic symptoms (OR = 2.3 (95% CI: 1.62-3.27)), anxiety (OR = 1.60 (1.08-2.37)), depression (OR = 1.49 (1.05-2.11)), self-harm, and suicide attempt (OR = 2.72 (1.56-4.75)), and lower quality of life (OR 1.64 (1.16-2.32)) and more loneliness (OR = 1.99 (1.28-3.10)) compared to participants without heart disease. Participants with CHD reported an increased somatic symptom burden (OR = 1.58 (1.16-2.16)). Despite a tendency to a higher score, this group did not differ significantly from the control group on anxiety or depression, quality of life, or loneliness. However, the risk of self-harm thoughts and suicidality was significantly increased (OR for suicide attempt 2.22 (1.3-3.77)). There was no difference between the groups on academic performance.

CONCLUSIONS

Although Norwegian students with heart disease reported more somatic symptoms, their academic progress was not reduced compared to students without heart disease. Students with CHD or arrhythmias showed an increased risk of self-harm thoughts and suicidality.

DiaSHoT18: A cross-sectional national health and well-being survey of university students with type 1 diabetes

OBJECTIVE

To achieve a better understanding in how university students live with and are able to manage their type 1 diabetes (T1D).

METHODS

In 2018, all fulltime Norwegian students aged 18 to 35 years pursuing higher education were invited into a national survey, which included data on demographics and health. In all, 162 512 students fulfilled these inclusion criteria. Students that stated having diabetes were asked to answer further questions about their diabetes care.

RESULTS

We included data from 50 054 students responding to the survey, and identified 324 students with T1D (64% females, mean age 23 years, mean HbA1c 7.65% [60 mmol/mol]). Male students had a lower HbA1c (7.28% vs 7.86%, 56 vs 62 mmol/mol), reached an HbA1c of <7.5% (58 mol/mol) more often (62.2% vs 44.2%) and were using continuous glucose measurement (CGM) less often (19.5% vs 36.7%). Exercise and smoking habits in students with T1D were equal to the non-diabetic group. More students with T1D were overweight or obese (44.1% vs 32.2%). Students who achieved an HbA1c <7.5% (58 mmol/mol) measured their blood sugar more often, had a lower body-mass index, exercised more and were smoking less. An HbA1c >7.5% (58 mmol/mol) was associated with less activity, more overweight or obesity, and smoking. The use of continuous subcutaneous insulin infusion and CGM was not associated with a better metabolic control.

CONCLUSIONS

These data have implications for the follow-up of adolescents and young adults, showing the need to focus on general lifestyle habits, especially in female subjects, whereas the use of technical devices might be of secondary importance.

Physical exercise and chronic pain in university students

Background

Physical inactivity and chronic pain are both major public health concerns worldwide. Although the health benefits of regular physical exercise are well-documented, few large epidemiological studies have investigated the association between specific domains of physical exercise and chronic pain in young adults. We sought to investigate the association between frequency, intensity and duration of physical exercise, and chronic pain.

Methods

Data stem from the SHoT2018-study, a national health survey for higher education in Norway, in which 36,625 fulltime students aged 18–35 years completed all relevant questionnaires. Chronic pain, defined according to the International Classification of Diseases 11th Revision (ICD-11), was assessed with a newly developed hierarchical digital instrument for reporting both distribution and characteristics of pain in predefined body regions. Physical exercise was assessed using three sets of questions, measuring the number of times exercising each week, and the average intensity and the number of hours each time.

Results

The majority (54%) of the students reported chronic pain in at least one location, and the prevalence was especially high among women. The overall pattern was an inverse dose-response association between exercise and chronic pain: the more frequent, harder or longer the physical exercise, the lower the risk of chronic pain. Similar findings were generally also observed for the number of pain locations: frequent exercise was associated with fewer pain locations. Adjusting for demographical, lifestyle factors and depression had little effect on the magnitude of the associations.

Conclusion

Given the many health benefits of regular exercise, there is much to be gained in facilitating college and university students to be more physically active, ideally, thru a joint responsibility between political and educational institutions. Due to the cross-sectional nature of the study, one should be careful to draw a firm conclusion about the direction of causality.

Physical exercise, mental health problems, and suicide attempts in university students

BACKGROUND

Physical inactivity and mental health problems are both major public health concerns worldwide. Although several studies have demonstrated the health benefits of regular physical exercise, few epidemiological studies have investigated the nature of the association between different aspects of physical exercise and mental health, and little is known regarding the possible link to suicidality.

STUDY AIM

To examine the association between frequency, intensity, and duration of physical exercise and mental health problems, and to explore whether low levels of physical activity is related to self-harm and suicide attempts among college and university students.

METHODS

We employed data from the SHoT2018-study, a national health survey for higher education in Norway, in which 50,054 students aged 18-35 years participated. Physical exercise was assessed with three questions (frequency, intensity, and duration). Mental health problems were assessed with both a screening tool assessing psychological distress (Hopkins Symptom Checklist-25; HSCL-25) and self-reported depressive disorder (using a pre-defined list of conditions). Suicide attempts and self-harm were assessed with two items from the Adult Psychiatric Morbidity Survey.

RESULTS

Physical exercise was negatively associated with all measures of mental health problems and suicidality in a dose-response manner. The strongest effect-sizes were observed for frequency of physical exercise. Women with low levels of physical activity had a near three-fold increased odds of both scoring high on the HSCL-25, and self-reported depression, compared to women exercising almost every day. Even stronger effect-sizes were observed for men (ORs ranging from 3.5 to 4.8). Also, physical exercise duration and intensity were significantly associated with mental health problems, but with generally smaller ORs. Similarly, graded associations were also observed when examining the link to self-harm and suicide attempts (ORs ranging from 1.9 to 2.5).

CONCLUSION

Given the demonstrated dose-response association between inactivity and both poor mental health, self-harm, and suicidal attempt, there is a need to facilitate college students to become more physically active. This is a shared responsibility that resides both on a political level and on the post-secondary institutions. The cross-sectional nature of the study means that one should be careful to draw firm conclusion about the direction of causality.

Physical exercise and body-mass index in young adults: a national survey of Norwegian university students

Background

Physical inactivity and obesity pose a major public health challenge. The aim of this study was to describe the level of physical exercise and body-mass index in college and university students, as well as to examine potential changes from 2010 to 2018.

Methods

Data stem from the SHoT study, a national student health survey for higher education in Norway, conducted at 4-year intervals. The SHOT studies conducted so far in 2010, 2014 and 2018, included 6053, 13,525 and 50,054 fulltime students (aged 18–35), respectively. Exercise frequency (average number of times exercising each week) was assessed in all three waves, and was used for the trend analysis. The last wave in 2018 also assessed the average intensity and duration of the exercise.

Results

Overall, students exercised less in 2018 compared to 2014, but comparable to level in 2010. The prevalence of overweight increased substantially from 2010 to 2018, but especially in the last 4 years and among older female students. Less than one of four male, and one of five female students, met the recommended criteria for both exercise frequency, intensity and duration. As expected, the associations between exercise and overweight/obesity were in a dose-response manner, and strong across all three waves.

Conclusions

Our findings show that the large majority of young adults fail to meet international recommendations on exercise, and that the proportion of overweight is increasing in both genders and across all age groups. We conclude that there is an urgent need for a broad approach to achieve a paradigm shift in supporting our college and university students to become more active.

Doubly Labeled Water Method and Accelerometer for the Measurement of Energy Expenditure in Human Immunodeficiency Virus-Infected Patients

BACKGROUND

Several studies have reported increased resting energy expenditure (REE) in human immunodeficiency virus (HIV)-infected patients with HIV-associated lipodystrophy syndrome (HALS). However, limited data exist on the total energy expenditure (TEE). This study was aimed at evaluating the REE and TEE of HIV-infected patients with and without HALS by using the doubly labeled water (DLW) technique and the activity monitor based on accelerometry system (AM), and comparing the results obtained using both methods.

METHODS

Evaluated total of 45 HIV+ men undergoing antiretroviral therapy, including 18 LIPO- (without lipodystrophy) and 27 LIPO+ (with lipodystrophy) individuals were evaluated. Habitual physical activity patterns were measured by using the ActivPAL™ AM system, REE by indirect calorimetry, and TEE by DLW and AM.

RESULTS

No significant differences were found between LIPO- and LIPO+ in REE (1,433 ± 196 vs. 1,510 ± 203 kcal), TEE-DLW (2,691 ± 856 vs. 2,618 ± 415 kcal) and TEE-AM (2,560 ± 458 vs. 2,594 ± 456 kcal), respectively. RQ was a predictor of REE in LIPO+. TEE estimated by the AM had a moderate correlation with DLW, but there was a wide variance in the intra-subject results.

CONCLUSIONS

TEE is not increased in HIV-infected patients with HALS. AM should be used with caution for TEE evaluation during clinical practice.

Estimation of Energy Expenditure Using a Patch-Type Sensor Module with an Incremental Radial Basis Function Neural Network

Conventionally, indirect calorimetry has been used to estimate oxygen consumption in an effort to accurately measure human body energy expenditure. However, calorimetry requires the subject to wear a mask that is neither convenient nor comfortable. The purpose of our study is to develop a patch-type sensor module with an embedded incremental radial basis function neural network (RBFNN) for estimating the energy expenditure. The sensor module contains one ECG electrode and a three-axis accelerometer, and can perform real-time heart rate (HR) and movement index (MI) monitoring. The embedded incremental network includes linear regression (LR) and RBFNN based on context-based fuzzy c-means (CFCM) clustering. This incremental network is constructed by building a collection of information granules through CFCM clustering that is guided by the distribution of error of the linear part of the LR model.

The use of individual cut points from treadmill walking to assess free-living moderate to vigorous physical activity in obese subjects by accelerometry: is it useful?

Background

Variation in counts between subjects at a given speed or work rate are the most important source of error in physical activity (PA) measurements with accelerometers. The aim of this study was to explore how the use of individual accelerometer cut points (ICPs) affected the analysis of PA field data.

Methods

We performed a treadmill calibration protocol to determine cut points for moderate to vigorous PA (MVPA) (≥3 metabolic equivalents) and assessed free-living PA in 44 severely obese subjects using the Actigraph GT1M accelerometer. We obtained cut points in 42 subjects (11 men, mean (standard deviation) of body mass index (BMI) 39.8 (5.7), age 43.2 (9.2) years), of whom 35 had valid measurement of free-living PA (minutes of MVPA/day). Linear regression was used to analyze associations with the ICPs and time in MVPA/day. MVPA/day was also compared with values derived using a group cut point (GCP).

Results

Resting oxygen consumption (partial r = 0.74, p < .001), work economy (partial r = −0.76, p < .001) and BMI (partial r = 0.52, p = .001) explained 68.4% of the variation in the ICPs (F = 26.7, p < .001). The ICPs explained 79.1% of the variation in the minutes spent in MVPA/day. Moderate to vigorous PA/day derived from the ICPs vs. the GCP varied substantially (R² = 14%, p = .023, coefficient of variation = 45.1%).

Conclusions

The results indicate that the use of ICPs had a strong influence on the PA level. Two thirds of the variation in the ICPs could be explained, however, a certain degree of measurement error will be present. Thus, we are not able to conclude with respect to the most appropriate procedure for analyzing time in MVPA.

Accurate prediction of energy expenditure using a shoe-based activity monitor

PURPOSE

The aim of this study was to develop and validate a method for predicting energy expenditure (EE) using a footwear-based system with integrated accelerometer and pressure sensors.

METHODS

We developed a footwear-based device with an embedded accelerometer and insole pressure sensors for the prediction of EE. The data from the device can be used to perform accurate recognition of major postures and activities and to estimate EE using the acceleration, pressure, and posture/activity classification information in a branched algorithm without the need for individual calibration. We measured EE via indirect calorimetry as 16 adults (body mass index=19-39 kg·m) performed various low- to moderate-intensity activities and compared measured versus predicted EE using several models based on the acceleration and pressure signals.

RESULTS

Inclusion of pressure data resulted in better accuracy of EE prediction during static postures such as sitting and standing. The activity-based branched model that included predictors from accelerometer and pressure sensors (BACC-PS) achieved the lowest error (e.g., root mean squared error (RMSE)=0.69 METs) compared with the accelerometer-only-based branched model BACC (RMSE=0.77 METs) and nonbranched model (RMSE=0.94-0.99 METs). Comparison of EE prediction models using data from both legs versus models using data from a single leg indicates that only one shoe needs to be equipped with sensors.

CONCLUSIONS

These results suggest that foot acceleration combined with insole pressure measurement, when used in an activity-specific branched model, can accurately estimate the EE associated with common daily postures and activities. The accuracy and unobtrusiveness of a footwear-based device may make it an effective physical activity monitoring tool.

Patient-focused endpoints in advanced cancer: criterion-based validation of accelerometer-based activity monitoring

BACKGROUND & AIMS

Objective assessment of daily physical activity (PA) by body-worn accelerometers offers potential as a novel endpoint in the clinical management of advanced cancer patients. This study aimed to assess criterion-based validity of an accelerometer-based activity monitoring system (AM-system), ActivPAL™, using two different methods.

METHODS

Advanced cancer in patients and outpatients (Karnofsky Performance Status (KPS) 40-100). ActivPAL™ measurements were validated against (i) observations and (ii) energy expenditure (EE) measured by 2-week doubly-labelled water (DLW) protocol.

RESULTS

Absolute errors for mean time spent in different body positions (<0.1%) and number of transfers (0%) were low. Step count error was significantly higher in patients with KPS 40-60 (non-self caring) compared to KPS 70-100 (self-caring) (33 vs. 24%, p = 0.006). Post-hoc mathematical analysis demonstrated that absolute errors for the mean energy expenditure of activity (EEA) (1.4%) and mean total EE (0.4%) were low, but agreement was also low.

CONCLUSIONS

AM-systems provide valid estimates of body positions and transfers, but not step count, especially in non-self caring patients. ActivPAL™ can derive estimates of EE but there is considerable variability in results, which is consistent, in part, with the inaccuracy in step count. Further studies are required to assess the validity of different endpoints derived from AM-systems in advanced cancer patients.

The long-term influence of orlistat on dietary intake in obese subjects with components of metabolic syndrome

BACKGROUND

Orlistat is a lipase inhibitor that reduces the intestinal absorption of fat and may enhance the effects of dietary and behavioural therapy on weight loss and maintenance. The present study examined the effect of orlistat on dietary intake, especially fat intake, during long-term weight maintenance.

METHODS

Subjects comprised 44 men and women (aged 18-63 years; body mass index 37.5 +/- 4.3 kg m(-2)) included in the Scandinavian Multicenter study of Obese subjects with the metabolic syndrome, a 3-year clinical trial of orlistat or placebo following an 8-week, very low energy diet (VLED). Two months after the end of the trial when the use of orlistat was optional, 33 subjects remained in the study. A dietary interview based on a validated food frequency questionnaire was conducted before the VLED, after 1 year of treatment with orlistat or placebo and 2 months after the end of the trial.

RESULTS

At 1 year, dietary intake did not differ between the orlistat and placebo group. Energy percent (E%) fat was reduced and E% carbohydrate was increased within both groups. Two months after the end of the trial, E% fat was 32.6% (SD 6.2%) in subjects that chose to take orlistat and 27.7% (SD 5.5%) in subjects not taking orlistat [between group difference -5.0% (95% confidence interval -9.2 to -0.7); P = 0.021].

CONCLUSIONS

The use of orlistat compared with placebo in a lifestyle modification programme does not appear to influence dietary intake. Subjects that chose to take orlistat after the end of the programme did not comply with dietary recommendations and this may hamper the effect of the drug.

Validation of self-reported recreational exercise in pregnant women in the Norwegian Mother and Child Cohort Study

We compared the self-reported frequency of recreational exercise and corresponding metabolic equivalent (MET)-minutes with physical activity measured with a position and motion sensor in pregnant women. One hundred and twelve women in the Norwegian Mother and Child Cohort Study (MoBa) completed questions about weekly participation in recreational exercise by week 17 of pregnancy and participated in the validation study around week 20. Data from a validated motion sensor (ActiReg) that measures physical activity and total energy expenditure (TEE) served as the "gold standard." Self-reported recreational exercise was compared with the following ActiReg-based measures: physical activity energy expenditure (PAEE), minutes of vigorous physical activity (VPA), physical activity level (PAL) and TEE. Pearson's correlations between self-reported weekly exercise and the objectively assessed variables were: rPAEE=0.26, rVPA=0.32, rPAL=0.30 (all P<0.01) and rTEE=0.17 (P=0.07). The partial correlation coefficients between the questionnaire responses and the ActiReg measurements were similar after adjusting for parity, body mass index, education, age, height and smoking, but rTEE increased (r=0.27, P<0.01). We observed significant positive associations between self-reported exercise activities and motion sensor measurements of physical activity, indicating that the questions used for exercise assessment in MoBa may be useful for ranking pregnant women according to the recreational exercise level.

Validity of resting energy expenditure estimated by an activity monitor compared to indirect calorimetry

The use of activity monitors (triaxial accelerometers) to estimate total energy expenditure in kilocalories is dependent on the estimation of resting energy expenditure (REE). However, the REE estimated by activity monitors has not been validated against more precise techniques, such as indirect calorimetry (IC). Therefore, the objective of the present study was to compare REE estimated by the Actical activity monitor (ActMon) to that measured by IC and standard prediction equations of REE. Fifty healthy adults between 18 and 43 years of age were measured for weight and percentage of body fat using a digital scale and bioelectrical impedance. The REE estimated by the ActMon was only 129 kJ/d higher, but not statistically different (P>0·05), than the REE measured with IC. Using multiple linear regression, there was a positive relationship for men, but not for women, between fat mass (kg) and percentage of body fat and the difference in REE estimated by the ActMon compared to IC (P < 0·001). Therefore, in the cohort studied, the use of an activity monitor to estimate REE is valid when compared to IC, but not to a standard prediction equation of REE.