Mental health and vitality predict spinal pain in healthcare workers

BACKGROUND

Despite extensive investigation of ergonomic risk factors for spinal pain in healthcare workers, limited knowledge of psychological risk factors exists.

AIMS

To assess the prospective association of mental health and vitality with development of spinal pain in healthcare workers.

METHODS

A prospective cohort study was carried out involving 1950 healthcare workers from 19 hospitals in Denmark. Assessments were done at baseline and at 1-year follow-up. Mental health and vitality were measured using the Short Form-36 Health Survey, while spinal pain intensity was measured using a 0-10 scale in the low-back, upper-back and neck, respectively. Cumulative logistic regressions adjusted for several confounding factors were applied, reporting risk estimates as odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Using good mental health as reference, moderate (but not poor) mental health at baseline was associated with increased pain intensity in the low-back (OR: 1.41 [95% CI: 1.21-1.77]), upper-back (OR: 1.63 [95% CI: 1.31-2.02]) and neck (OR: 1.31 [95% CI: 1.07-1.61]) at 1-year follow-up. Likewise, using high vitality as reference, both moderate and low vitality at baseline were associated with increased pain intensity in the low-back (OR: 1.54 [95% CI: 1.22-1.94] and OR: 2.34 [95% CI: 1.75-3.12], respectively), upper-back (OR: 1.72 [95% CI: 1.34-2.23] and OR: 2.46 [95% CI: 1.86-3.25], respectively) and neck (OR: 1.66 [95% CI: 1.34-2.06] and OR: 2.06 [95% CI: 1.61-2.63], respectively) at 1-year follow-up.

CONCLUSIONS

Compared to healthcare workers with good mental health and high vitality, those with moderate mental health and low/moderate vitality, respectively, were more likely to increase spinal pain intensity at 1-year follow-up. These components should also be considered in the prevention of spinal pain in healthcare workers.

Handgrip strength and respiratory disease mortality: Longitudinal analyses from SHARE

BACKGROUND

While the association between handgrip strength and all-cause mortality is more deeply explored, no previous studies have been specifically focused on handgrip strength and respiratory disease mortality. The purpose of the study was to investigate the association between handgrip strength and respiratory disease mortality in a large representative sample.

METHODS

Individuals aged 50 or over from 27 European countries and Israel participated in this longitudinal study. Data on handgrip strength and all-cause and respiratory disease mortality were retrieved from the Survey of Health, Ageing and Retirement in Europe (SHARE) waves 1, 2, 4, 5, 6 and 7. We estimated the sub hazard ratios (SHRs) for respiratory disease mortality using a Fine-Gray sub-distribution method with both time-varying exposure and covariates and mortality due to other causes as competing risk. Furthermore, we assessed dose-response associations of handgrip strength (modelled as a continuous exposure) with respiratory disease mortality using restricted cubic splines and estimated hazard ratios (HRs).

RESULTS

We included 60,883 men and 74,904 women with a mean age of 63.6 (SD 9.7) years at study entry. During a median (interquartile range) of 7.4 years of follow-up 565 (0.4%) participants died due to respiratory diseases. The increase of 1 single kg of handgrip strength showed a 6% incidence reduction on respiratory disease mortality (SHR, 0.94; 95%CI, 0.92-0.96) after adjusting for potential confounders. Furthermore, each kg increase of handgrip strength reduced respiratory disease mortality risk in a dose-response fashion and a significant threshold for values of 41 kg (HR, 0.49; 95%CI, 0.26-0.92) and higher was identified.

CONCLUSIONS

Higher handgrip strength is associated with lower mortality due to respiratory disease. Intervention studies are needed to determine whether strength training in respiratory disease patients can prevent premature mortality.

The unexplored role of sedentary time and physical activity in glucose and lipid metabolism-related placental mRNAs in pregnant women who are obese: the DALI lifestyle randomised controlled trial

OBJECTIVE

We aimed to explore: (i) the association of sedentary time (ST) and physical activity (PA) during pregnancy with the placental expression of genes related to glucose and lipid metabolism in pregnant women who are obese; (ii) maternal metabolic factors mediating changes in these placental transcripts; and (iii) cord blood markers related to the mRNAs mediating neonatal adiposity.

DESIGN

Multicentre randomised controlled trial.

SETTING

Hospitals in nine European countries.

POPULATION

A cohort of 112 pregnant women with placental tissue.

METHODS

Both ST and moderate-to-vigorous PA (MVPA) levels were measured objectively using accelerometry at three time periods during pregnancy.

MAIN OUTCOME MEASURES

Placental mRNAs (FATP2, FATP3, FABP4, GLUT1 and PPAR-γ) were measured with NanoString technology. Maternal and fetal metabolic markers and neonatal adiposity were assessed.

RESULTS

Longer periods of ST, especially in early to middle pregnancy, was associated with lower placental FATP2 and FATP3 expression (P < 0.05), whereas MVPA at baseline was inversely associated with GLUT1 mRNA (P = 0.02). Although placental FATP2 and FATP3 expression were regulated by the insulin-glucose axis (P < 0.05), no maternal metabolic marker mediated the association of ST/MVPA with placental mRNAs (P > 0.05). Additionally, placental FATP2 expression was inversely associated with cord blood triglycerides and free fatty acids (FFAs; P < 0.01). No cord blood marker mediated neonatal adiposity except for cord blood leptin, which mediated the effects of PPAR-γ on neonatal sum of skinfolds (P < 0.05).

CONCLUSIONS

In early to middle pregnancy, ST is associated with the expression of placental genes linked to lipid transport. PA is hardly related to transporter mRNAs. Strategies aimed at reducing sedentary behaviour during pregnancy could modulate placental gene expression, which may help to prevent unfavourable fetal and maternal pregnancy outcomes.

TWEETABLE ABSTRACT

Reducing sedentary behaviour in pregnancy might modulate placental expression of genes related to lipid metabolism in women who are obese.

Association between physical activity and sickness absenteeism in university workers

BACKGROUND

Sedentary occupations have increased by more than 10% in Western countries over the last two decades, and the yearly global cost of physical inactivity has been estimated to be $53.8 billion. As workers tend to move less in the workplace, they are more likely to develop a sedentarism-related chronic condition and to be absent from work due to illness, although research evidence on the issue remains unclear.

AIMS

To investigate associations between physical activity (PA) and sickness absenteeism in the workplace among Spanish university workers.

METHODS

We conducted cross-sectional research with data from 1025 workers aged 18-65 years (43% women) from a Spanish university. Physical Activity Vital Sign (PAVS) and International Physical Activity Questionnaire (IPAQ) short versions were used to evaluate levels of PA. Workplace absenteeism was self-reported by participants. Written questionnaires distributed during medical checks included PAVS, IPAQ and the question about absenteeism among other information. The association between PA and sickness absenteeism was examined using adjusted multiple linear regression.

RESULTS

After adjusting for age, sex, job function, chronic conditions, sedentarism and smoking, each weekly hour of PA reduced sickness absence by -1.20 (95% confidence interval: -2.40-0.00) days per year.

CONCLUSIONS

The implementation of PA promotion strategies aimed at university employees may lead to a reduction of days off work due to illness.

Less sedentary time is associated with a more favourable glucose-insulin axis in obese pregnant women-a secondary analysis of the DALI study

Background/objectives

Obese pregnant women are at high risk of developing gestational diabetes mellitus (GDM), which might be reduced by sufficient physical activity (PA) and reduced sedentary time (ST). We assessed whether PA and ST are longitudinally associated with the glucose-insulin axis in obese pregnant women.

Subjects/methods

In this secondary analysis of the DALI (vitamin D And Lifestyle Intervention for gestational diabetes mellitus prevention) study, pregnant women, <20 weeks gestation, with a pre-pregnancy body mass index (BMI) ≥ 29 kg/m², without GDM on entry were included. Time spent in moderate-to-vigorous PA (MVPA) and ST were measured objectively with accelerometers at <20 weeks, 24–28 weeks and 35–37 weeks of gestation. Fasting glucose (mmol/l) and insulin (mU/l), insulin resistance (HOMA-IR) and first-phase and second-phase insulin release (Stumvoll first and second phase) were assessed at the same time. Linear mixed regression models were used to calculate between-participant differences and within-participant changes over time. Analyses were adjusted for gestational age, randomisation, pre-pregnancy BMI, education and age. MVPA, Insulin, HOMA-IR and Stumvoll first and second phase were log-transformed for analyses due to skewness.

Results

232 women were included in the analysis. Concerning differences between participants, more ST was associated with higher fasting glucose (Estimate: 0.008; 95% CI: 0.002, 0.014), fasting insulin (0.011; 0.002, 0.019), HOMA-IR (0.012; 0.004, 0.021) and Stumvoll first and second phase (0.008; 0.001, 0.014 and 0.007; 0.001, 0.014). Participants with more MVPA had lower Stumvoll first and second phase (−0.137; −0.210, −0.064 and −0.133; −0.202, −0.063). Concerning changes over time, an increase in ST during gestation was associated with elevated Stumvoll first and second phase (0.006; 0.000, 0.011).

Conclusions

As the glucose-insulin axis is more strongly associated with ST than MVPA in our obese population, pregnant women could be advised to reduce ST in addition to increasing MVPA. Moreover, our findings suggest that behaviour change interventions aiming at GDM risk reduction should start in early or pre-pregnancy.

Are Moderate and Vigorous Leisure-Time Physical Activity Associated With Musculoskeletal Pain? A Cross-Sectional Study Among 981 Physical Therapists

PURPOSE

Musculoskeletal pain (MP) is common among workers, especially for health-care professionals. Paradoxically, many of those rehabilitating patients for pain-that is, physical therapists (PTs)-also have pain. Adequate levels of physical activity are recommended for cardiovascular and musculoskeletal health. However, the association between physical activity and MP among PTs remains unknown. This study aims to determine the association between moderate and vigorous leisure-time physical activity levels and MP in PTs.

DESIGN

Cross-sectional study.

SETTING

Workplace.

PARTICIPANTS

Nine hundred eighty-one PTs.

MEASURES

Data on MP and leisure-time physical activity were collected using an online survey.

ANALYSIS

The odds for having lower level of MP as a function of physical activity were estimated using binary logistic regression controlled for various confounders.

RESULTS

Performing ≥75 min/week of vigorous leisure-time physical activity increased the odds of experiencing lower levels of neck-shoulder pain (odds ratio = 1.43, 95% confidence interval, 1.05-1.94). No association was found neither between vigorous nor between moderate leisure-time physical activity and MP in the arm-hand or back.

CONCLUSION

Performing ≥75 min/week of vigorous leisure-time physical activity is associated with lower levels of MP in neck and shoulders among PTs. No associations were found between vigorous or moderate leisure-time physical activity and MP in arm-hand and back.

A reduction in sedentary behaviour in obese women during pregnancy reduces neonatal adiposity: the DALI randomised controlled trial

AIMS/HYPOTHESIS

Offspring of obese women are at increased risk of features of the metabolic syndrome, including obesity and diabetes. Lifestyle intervention in pregnancy might reduce adverse effects of maternal obesity on neonatal adiposity.

METHODS

In the Vitamin D And Lifestyle Intervention for Gestational Diabetes Mellitus (GDM) Prevention (DALI) lifestyle trial, 436 women with a BMI ≥29 kg/m² were randomly assigned to counselling on healthy eating (HE), physical activity (PA) or HE&PA, or to usual care (UC). In secondary analyses of the lifestyle trial, intervention effects on neonatal outcomes (head, abdominal, arm and leg circumferences and skinfold thicknesses, estimated fat mass, fat percentage, fat-free mass and cord blood leptin) were assessed using multilevel regression analyses. Mediation of intervention effects by lifestyle and gestational weight gain was assessed.

RESULTS

Outcomes were available from 334 neonates. A reduction in sum of skinfolds (-1.8 mm; 95% CI -3.5, -0.2; p = 0.03), fat mass (-63 g; 95% CI -124, -2; p = 0.04), fat percentage (-1.2%; 95% CI -2.4%, -0.04%; p = 0.04) and leptin (-3.80 μg/l; 95% CI -7.15, -0.45; p = 0.03) was found in the HE&PA group, and reduced leptin in female neonates in the PA group (-5.79 μg/l; 95% CI -11.43, -0.14; p = 0.05) compared with UC. Reduced sedentary time, but not gestational weight gain, mediated intervention effects on leptin in both the HE&PA and PA groups.

CONCLUSIONS/INTERPRETATION

The HE&PA intervention resulted in reduced adiposity in neonates. Reduced sedentary time seemed to drive the intervention effect on cord blood leptin. Implications for future adiposity and diabetes risk of the offspring need to be elucidated.

TRIAL REGISTRATION

ISRCTN70595832.

Influence of physical and psychosocial working conditions for the risk of disability pension among healthy female eldercare workers: Prospective cohort

Aim: To investigate the influence of physical and psychosocial working conditions on the risk of disability pension among eldercare workers. Methods: After responding to a questionnaire in 2005, 4699 healthy female eldercare workers – free from chronic musculoskeletal pain, depressive symptoms and long-term sickness absence – were followed for 11 years in the Danish Register for Evaluation of Marginalization. Time-to-event analyses estimated the hazard ratio (HR) for disability pension from physical exertion during work, emotional demands, influence at work, role conflicts, and quality of leadership. Analyses were mutually adjusted for these work environmental factors as well as for age, education, smoking, leisure physical activity and body mass index. Results: During follow-up, 7.6% received disability pension. Physical exertion and emotional demands were associated with risk of disability pension, and both interacted with age. In age-stratified analyses, older eldercare workers (mean age 53 years at baseline) with moderate and high physical exertion (reference: low) were at increased risk with HRs of 1.51, 95% CI [1.06–2.15] and 2.54, 95% CI [1.34–4.83], respectively. Younger eldercare workers (mean age 36 years at baseline) with moderate emotional demands (reference: low) were at decreased risk with an HR of 0.57, 95% CI [0.37–0.85]. Conclusions: While a higher level of physical exertion is a risk factor for disability pension among older female eldercare workers, a moderate level of emotional demands is associated with lower risk among the younger workers. The age of the worker may be an important factor when providing recommendations for promoting a long and healthy working life.

Influence of strength training intensity on subsequent recovery in elderly

Understanding the influence of strength training intensity on subsequent recovery in elderly is important to avoid reductions in physical function during the days following training. Twenty-two elderly were randomized in two groups: G70 (65.9 ± 4.8 years, n = 11) and G95 (66.9 ± 5.1, n = 11). Baseline tests included maximum voluntary isometric contraction (peak torque and rate of torque development - RTD), countermovement jump, and functional capacity (timed up and go, stairs ascent and descent). Then, both groups performed a single strength training session with intensities of 70% (G70) or 95% (G95) of five repetition maximum. The same tests were repeated immediately, 24 h, 48 h, and 72 h after the session. Peak torque was lower than baseline immediately after for both groups and at 24 h for G95. Compared with G70, G95 had lower peak torque at 24 h and 48 h. Countermovement jump, timed up and go, stairs ascent, and RTD at 0-50 ms only differed from baseline immediately after for both groups. RTD at 0-200 ms was lower than baseline immediately after and 24 h after the session for both groups. In conclusion, reduced physical function immediately after strength training can last for 1-2 days in elderly depending on the type of physical function and intensity of training. Higher intensity resulted in greater impairment. Exercise prescription in elderly should take this into account, e.g., by gradually increasing intensity during the first months of strength training. These results have relevance for elderly who have to be fit for work or other activities in the days following strength training.

Effect of resistance training on headache symptoms in adults: Secondary analysis of a RCT

BACKGROUND

While strength training for the neck and shoulder muscles may be effective in reducing headache, the optimal combination of exercise frequency and duration is unknown. This study investigates the effect of different time-wise combinations of one weekly hour of strength training for the neck and shoulder muscles on headache frequency, intensity, and use of analgesics.

METHODS

A total of 573 office workers were randomly allocated at the cluster-level to five groups; 3 × 20 min a week of minimally supervised (3MS), 1 × 60 (1WS), 3 × 20 (3WS) or 9 × 7 (9WS) min a week of supervised high-intensity strength training for 20 weeks, or to a reference group without training (REF). Headache frequency, intensity, and use of analgesics in relation to headache were determined by questionnaire at baseline and follow-up.

RESULTS

The intention-to-treat analysis showed reduced headache frequency and intensity of approximately 50% in all training groups compared with REF at 20-week follow-up (P < 0.001). Use of analgesics was lower in the supervised training groups (1WS, 3WS and 9WS), but not in the group with minimal training supervision (3MS), compared with REF at follow-up.

CONCLUSION

One hour of specific strength training - regardless of the distribution during the week - effectively reduced both headache frequency and intensity in office workers. Thus, a large time-wise flexibility exists when implementing specific strength training at the workplace. However, only supervised training led to a reduction in use of analgesics for headache.

Factors affecting pain relief in response to physical exercise interventions among healthcare workers

The aim of this study is to identify factors associated with musculo-skeletal pain reduction during workplace-based or home-based physical exercise interventions among healthcare workers. Two hundred female healthcare workers (age: 42.0, BMI: 24.1, average pain intensity: 3.1 on a scale of 0-10) from three hospitals participated. Participants were randomly allocated at the cluster level (18 departments) to 10 weeks of (i) workplace physical exercise (WORK) performed in groups during working hours for 5 × 10 minutes per week and up to five group-based coaching sessions on motivation for regular physical exercise, or (ii) home-based physical exercise (HOME) performed alone during leisure-time for 5 × 10 minutes per week. Linear mixed models accounting for cluster identified factors affecting pain reduction. On average 2.2 (SD: 1.1) and 1.0 (SD: 1.2) training sessions were performed per week in WORK and HOME, respectively. The multi-adjusted analysis showed a significant effect on pain reduction of both training adherence (P=.04) and intervention group (P=.04) with participants in WORK experiencing greater reductions compared with HOME. Obesity at baseline was associated with better outcome. Leisure-time exercise, daily patient transfer, age, and chronic pain did not affect the changes in pain. In conclusion, even when adjusted for training adherence, performing physical exercise at the workplace is more effective than home-based exercise in reducing musculo-skeletal pain in healthcare workers. Noteworthy, obese individuals may especially benefit from physical exercise interventions targeting musculo-skeletal pain.

Regular use of medication for musculoskeletal pain and risk of long-term sickness absence: A prospective cohort study among the general working population

BACKGROUND

The aim was to determine the prospective association between use of pain medication - due to musculoskeletal pain in the low back, neck/shoulder and hand/wrist - and long-term sickness absence.

METHODS

Cox-regression analysis was performed to estimate the prospective association between regular use of pain medication and long-term sickness absence (LTSA; at least 6 consecutive weeks) among 9,544 employees from the general working population (Danish Work Environment Cohort Study 2010) and free from LTSA during 2009-2010. The fully adjusted model was controlled for age, gender, body mass index, smoking, leisure physical activity, job group, physical activity at work, psychosocial work environment, pain intensity, mental health and chronic disease.

RESULTS

In 2010, the proportion of regular pain medication users due to musculoskeletal disorders was 20.8%: 13.4% as over-the-counter (i.e. non-prescription) and 7.4% as doctor prescribed. In the fully adjusted model, regular use of over-the-counter [HR 1.44 (95% CI 1.13-1.83)] and doctor prescribed (HR 2.18 (95% CI 1.67-2.86)) pain medication were prospectively associated with LTSA.

CONCLUSIONS

Regular use of pain medication due to musculoskeletal pain is prospectively associated with LTSA even when adjusted for pain intensity. This study suggests that use of pain medication can be an important factor to be aware of in the prevention of sickness absence. Thus, regular use of pain medication - and not solely the intensity of pain - can be an early indicator that musculoskeletal pain can lead to serious consequences such as long-term sickness absence.

SIGNIFICANCE

Use of medication due to musculoskeletal pain is prospectively associated with long-term sickness absence even when adjusted for pain intensity. Use of pain medication can be a red flag to be aware of in the prevention of sickness absence.

Validity and reliability of elastic resistance bands for measuring shoulder muscle strength

Valid and reliable measurements of muscle strength are important in sport medicine. This study assesses concurrent validity and intrarater reliability (test-retest reliability) of elastic resistance bands for measuring shoulder muscle strength. Altogether, 50 healthy adults [mean age 36.0 (SD: 11.6), 29 women and 21 men] participated in testing and retesting 1-2 weeks later. The maximal elastic resistance (TheraBand) that each participant could hold for 3 s during standing bilateral shoulder abduction to 90° was converted into torque and validated against gold standard maximal voluntary isometric contraction (MVC) (Vishay force transducer) performed unilaterally while lying supine. The intrarater reliability of both tests were high; for the MVC and elastic band test, respectively, ICC(3,1) was 0.98 (95% CI: 0.97-0.99) and 0.99 (95% CI: 0.98-1.00), and measurement error was 4.8% (95% CI: 3.7-5.9) and 4.7% (95% CI: 3.1-6.2). For concurrent validity, ICC(3,1) was 0.96 (95% CI: 0.95-0.98) and measurement error was 8.1% (95% CI: 6.6-9.6), and the elastic band test explained 93% of the variance in the MVC test. However, the elastic band test produced systematically lower torque values than the MVC [56.5 (SD: 26.8) vs 66.5 (SD: 25.5) Nm, P < 0.01]. In conclusion, the test for shoulder muscle strength using elastic resistance bands has excellent validity and reliability, but produces systematically lower torque values than MVC. The reason for the lower torque values may be that the elastic band test has an initial concentric phase and is performed bilaterally and standing upright.

Efficacy of recreational football on bone health, body composition, and physical functioning in men with prostate cancer undergoing androgen deprivation therapy: 32-week follow-up of the FC prostate randomised controlled trial

Androgen deprivation therapy (ADT) for prostate cancer (PCa) impairs musculoskeletal health. We evaluated the efficacy of 32-week football training on bone mineral density (BMD) and physical functioning in men undergoing ADT for PCa. Football training improved the femoral shaft and total hip BMD and physical functioning parameters compared to control.

INTRODUCTION

ADT is a mainstay in PCa management. Side effects include decreased bone and muscle strength and increased fracture rates. The purpose of the present study was to evaluate the effects of 32 weeks of football training on BMD, bone turnover markers (BTMs), body composition, and physical functioning in men with PCa undergoing ADT.

METHODS

Men receiving ADT >6 months (n = 57) were randomly allocated to a football training group (FTG) (n = 29) practising 2-3 times per week for 45-60 min or to a standard care control group (CON) (n = 28) for 32 weeks. Outcomes were total hip, femoral shaft, femoral neck and lumbar spine (L2-L4) BMD and systemic BTMs (procollagen type 1 amino-terminal propeptide, osteocalcin, C-terminal telopeptide of type 1 collagen). Additionally, physical functioning (postural balance, jump height, repeated chair rise, stair climbing) was evaluated.

RESULTS

Thirty-two-week follow-up measures were obtained for FTG (n = 21) and for CON (n = 20), respectively. Analysis of mean changes from baseline to 32 weeks showed significant differences between FTG and CON in right (0.015 g/cm(2)) and left (0.017 g/cm(2)) total hip and in right (0.018 g/cm(2)) and left (0.024 g/cm(2)) femoral shaft BMD, jump height (1.7 cm) and stair climbing (-0.21 s) all in favour of FTG (p < 0.05). No other significant between-group differences were observed.

CONCLUSIONS

Compared to standard care, 32 weeks of football training improved BMD at clinically important femoral sites and parameters of physical functioning in men undergoing ADT for PCa.

Self-reported previous knee injury and low knee function increase knee injury risk in adolescent female football

Knee injuries are common in adolescent female football. Self-reported previous knee injury and low Knee injury and Osteoarthritis Outcome Score (KOOS) are proposed to predict future knee injuries, but evidence regarding this in adolescent female football is scarce. The aim of this study was to investigate self-reported previous knee injury and low KOOS subscale score as risk factors for future knee injuries in adolescent female football. A sample of 326 adolescent female football players, aged 15-18, without knee injury at baseline, were included. Data on self-reported previous knee injury and KOOS questionnaires were collected at baseline. Time-loss knee injuries and football exposures were reported weekly by answers to standardized text-message questions, followed by injury telephone interviews. A priori, self-reported previous knee injury and low KOOS subscale scores (< 80 points) were chosen as independent variables in the risk factor analyses. The study showed that self-reported previous knee injury significantly increased the risk of time-loss knee injury [relative risk (RR): 3.65, 95% confidence (CI) 1.73-7.68; P < 0.001]. Risk of time-loss knee injury was also significantly increased in players with low KOOS subscale scores (< 80 points) in Activities of Daily Living (RR: 5.0), Sport/Recreational (RR: 2.2) and Quality of Life (RR: 3.0) (P < 0.05). In conclusion, self-reported previous knee injury and low scores in three KOOS subscales significantly increase the risk of future time-loss knee injury in adolescent female football.

Socio-economic status and incident diabetes mellitus among employees in Denmark: a prospective analysis with 10-year follow-up

AIMS

To contribute to the research on diabetes and social inequality by presenting national data on incident diabetes mellitus, stratified according to socio-economic status.

METHODS

National registers were combined, linking socio-economic status with incident diabetes over a 10-year period (2001-2010). The study population comprised employees in Denmark aged 20-59 years at baseline. Poisson regression analysis was used to estimate socio-economic rate ratios. Excess fraction analysis was used to determine the proportion of cases that would not have occurred if morbidity rates in each socio-economic group had been as low as those in the reference group. Monte Carlo simulation was used to calculate 95% CIs for excess fraction estimates

RESULTS

A total of 1 005 572 men and 951 039 women were included in the analysis. The follow-up yielded 43 439 cases in 9 533 199 person-years at risk among men and 29 266 cases in 9 163 405 person-years at risk among women. Using 'professionals' as a reference group, higher levels of relative risk were observed among every other socio-occupational group. The excess fraction was, 0.342 (95% CI 0.329-0.354) among men and 0.359 (95% CI 0.349-0.369) among women.

CONCLUSIONS

Excess fraction analysis suggests that more than a third of cases of diabetes could be prevented if all employees were exposed to the same working conditions as the reference population. Acknowledging potential confounders, the observed levels of incident diabetes among the workforce highlight the potential gains to be had by better use of the workplace as an arena for prevention. Greater integration of occupational health and general healthcare is required to achieve this.

Effect of strength training in addition to general exercise in the rehabilitation of patients with non-specific neck pain. A randomized clinical trial

BACKGROUND

The optimal type of exercise protocol in the physical rehabilitation of non-specific neck pain has not yet been established. Furthermore, the role of fear-avoidance belief in the maintenance of pain and disability has been highlighted. Research indicates that exercise may be a means to reduce fear-avoidance belief, but evidence is scarce.

AIM

To compare the effect of two different exercise programs on pain, strength and fear-avoidance belief.

DESIGN

Randomized clinical trial.

SETTING

A specialized outpatient hospital clinic in Denmark.

POPULATION

Twenty-three men and 60 women on sick leave due to non-specific neck pain.

METHODS

Participants were randomized to either general physical activity (GPA group) or GPA and additional strength training of the neck and shoulder (SST group). The primary outcome was pain intensity. Secondary outcomes were muscle strength of the neck and shoulder and fear-avoidance belief.

RESULTS

Pain was significantly reduced within groups with a median of -1 (IQR: -3 to 0, P<0.001) in the SST group and -1 (IQR: -4 to 1, P=0.046) in the GPA group. The difference between groups was not significant. Changes in strength did not differ between groups. Both groups experienced significant increases in neck flexion strength of 14.7 N (IQR: -1 to 28.4, P=0. 001) in the SST group and 6.9 N (IQR: -4.9 to18.6, P=0.014) in the GPA group. Furthermore, the SST group achieved an increase of 18.6 N (IQR: -2.6 to 69.7, P=0.005) in neck extension. Fear-avoidance beliefs improved with 6 (IQR: 3 to 12, P<0.001) in the SST group, while the GPA group improved with 3 (IQR: 0 to 8, P=0.004). This between-group difference was significant (P=0.046).

CONCLUSION AND REHABILITATION IMPACT

This study indicates that in rehabilitation of subjects severely disabled by non-specific neck pain, there is no additional improvement on pain or muscle strength when neck exercises are given as a home-based program with a minimum of supervision. However, strength training of the painful muscles seems to be effective in decreasing fear-avoidance beliefs.

Effect of football or strength training on functional ability and physical performance in untrained old men

The effects of 16 weeks of football or strength training on performance and functional ability were investigated in 26 (68.2 ± 3.2 years) untrained men randomized into a football (FG; n = 9), a strength training (ST; n = 9), or a control group (CO; n = 8). FG and ST trained 1.6 ± 0.1 and 1.5 ± 0.1 times per week, respectively, with higher (P < 0.05) average heart rate (HR) (∼140 vs 100 bpm) and time >90%HRmax (17 vs 0%) in FG than ST, and lower (P < 0.05) peak blood lactate in FG than ST (7.2 ± 0.9 vs 10.5 ± 0.6 mmol/L). After the intervention period (IP), VO₂ max (15%; P < 0.001), cycle time to exhaustion (7%; P < 0.05), and Yo-Yo Intermittent Endurance Level 1 performance (43%; P < 0.01) were improved in FG, but unchanged in ST and CO. HR during walking was 12% and 10% lower (P < 0.05) in FG and ST, respectively, after IP. After IP, HR and blood lactate during jogging were 7% (P < 0.05) and 30% lower (P < 0.001) in FG, but unchanged in ST and CO. Sit-to-stand performance was improved (P < 0.01) by 29% in FG and 26% in ST, but not in CO. In conclusion, football and strength training for old men improves functional ability and physiological response to submaximal exercise, while football additionally elevates maximal aerobic fitness and exhaustive exercise performance.

Should physical activity recommendation depend on state of low back pain?

BACKGROUND

Leisure time physical activity is recommended for preventing long-term sickness absence (LTSA). Although low back pain (LBP) is a risk factor for sickness absence and physical activity is recommended for people with LBP, it is unknown if leisure time physical activity prevents LTSA among persons with different levels of LBP.

METHODS

Prospective cohort study among 8655 Danish female healthcare workers responding to a questionnaire in 2004-2005 on leisure time physical activity and LBP, and subsequently followed for 1 year on periods with LTSA ∼2 consecutive weeks or more of sickness absence in a national register of social transfer payments (DREAM). Multi-adjusted Cox regression analysis was used to model risk estimates for LTSA associated with low, moderate, high and very high leisure time physical activity at baseline among healthcare workers with no LBP (0 days past 12 months, n = 2761), non-chronic LBP (1-30 days the past 12 months, n = 3942) and persistent LBP (>30 days the past 12 months, n = 1952).

RESULTS

A strongly reduced risk for LTSA from high leisure time physical activity was found among healthcare workers with no LBP [hazard ratio (HR): 95% confidence interval (CI) 0.47:0.23-0.97 for low vs. very high activity] and non-chronic LBP (HR: 95%CI 0.43:0.23-0.84 of low vs. very high activity), but not among healthcare workers with persistent LBP (HR: 95%CI 1.15:0.55-2.44 of low vs. very high activity).

CONCLUSIONS

Leisure time physical activity is a strong predictive factor on LTSA among female healthcare workers with no and non-chronic LBP, but not among those with more persistent LBP.

Does work-site physical activity improve self-reported psychosocial workplace factors and job satisfaction? A randomized controlled intervention study

PURPOSE

To investigate whether a work-site strength-training program has a positive effect on self-reported psychosocial workplace factors and job satisfaction.

METHODS

We conducted a randomized controlled trial among laboratory technicians implementing neck and shoulder exercises for pain relief, with 199 participants in the training group and 228 in the control group. Influence at work, sense of community, time pressure, and job satisfaction were measured with the Copenhagen Psychosocial Questionnaire at baseline and post-intervention after 20 weeks.

RESULTS

There was no statistically significant change in any of the four variables in the training group from baseline to follow-up (all p ≥ 0.39). When we used MANOVA to test for between-group effects over time, we did not find any statistically significant result (all p > 0.14).

CONCLUSIONS

This study does not provide evidence for an effect of a work-site strength-training program on self-reported psychosocial workplace factors and job satisfaction.

Does occupational lifting and carrying among female health care workers contribute to an escalation of pain-day frequency?

BACKGROUND

The aim of the study was to investigate if different frequencies, loads and trunk postures of occupational lifting and carrying increases the risk of sub-chronic (1-30 days last 12 months) low back pain (LBP) to become persistent (>30 days last 12 months) among female health care workers.

METHODS

Female health care workers answered a questionnaire about occupational lifting or carrying frequency (rarely, occasionally and frequently), load (low: 1-7 kg, moderate: 8-30 kg and heavy: >30 kg) and trunk posture (upright or forward bent back), and days with LBP in 2005 and 2006.

RESULTS

The odds ratio (OR) for developing persistent LBP in 2006 from these characteristics of occupational lifting and carrying was investigated with multi-adjusted logistic regressions among female health care workers with sub-chronic LBP (n = 2381) in 2005. Among health care workers with sub-chronic LBP, increased risk of persistent LBP was found from frequently lifting or carrying with forward bent back of moderate loads (OR: 1.63; 95% CI: 1.15-2.33) and heavy loads (OR: 1.56; 95% CI: 1.04-2.34). No increased risk for LBP to develop into a persistent condition was found for frequent lifting with upright back, frequent lifting or carrying of light loads, or occasionally lifting or carrying of any loads.

CONCLUSIONS

Preventive initiatives for sub-chronic LBP to develop into a persistent condition ought to focus on reducing frequent lifting and carrying of moderate and heavy loads with forward bent back.

Spreading of chronic pain between body regions: prospective cohort study among health care workers

OBJECTIVE

To estimate the prognostic value of pain in one body region on the risk for developing chronic pain in other body regions.

METHODS

Prospective cohort study among 5052 Danish female health care workers responding to a baseline and follow-up questionnaire in 2005 and 2006, respectively. Using adjusted logistic regression analysis, the risk for developing chronic pain (>30 days last year) at follow-up in the low back (among those without low back pain during the last year at baseline) when experiencing sub-chronic (1-30 days last year) or chronic pain in other body regions (i.e., the neck/shoulders and/or the knees at baseline) was modelled. Similar risks were modelled for developing chronic pain in the neck/shoulders and knees.

RESULTS

Chronic pain in the neck/shoulders (OR 3.14; 95% CI 1.74-5.70) or knees (OR 2.57; 95% CI 1.28-5.16) at baseline increased the risk for developing chronic pain in the low back at follow-up. Likewise, chronic pain in the neck/shoulders (OR 2.39; 95% CI 1.36-4.17) or low back (OR 1.82 95%; CI 1.07-3.09) at baseline increased the risk for developing chronic pain in the knees at follow-up. The risk for developing chronic neck/shoulder pain was not significantly increased when having pain in the low back or knees at baseline.

CONCLUSION

Among health care workers, chronic musculoskeletal pain in one body region increases the risk for developing chronic pain in other pain-free body regions. Prevention of musculoskeletal disorders among health care workers should focus holistically on the musculoskeletal system.

Local NSAID infusion inhibits satellite cell proliferation in human skeletal muscle after eccentric exercise

Despite the widespread consumption of nonsteroidal anti-inflammatory drugs (NSAIDs), the influence of these drugs on muscle satellite cells is not fully understood. The aim of the present study was to investigate the effect of a local NSAID infusion on satellite cells after unaccustomed eccentric exercise in vivo in human skeletal muscle. Eight young healthy males performed 200 maximal eccentric contractions with each leg. An NSAID was infused via a microdialysis catheter into the vastus lateralis muscle of one leg (NSAID leg) before, during, and for 4.5 h after exercise, with the other leg working as a control (unblocked leg). Muscle biopsies were collected before and 8 days after exercise. Changes in satellite cells and inflammatory cell numbers were investigated by immunohistochemistry. Satellite cells were identified using antibodies against neural cell adhesion molecule and Pax7. The number of Pax7(+) cells per myofiber was increased by 96% on day 8 after exercise in the unblocked leg (0.14 +/- 0.04, mean +/- SE) compared with the prevalue (0.07 +/- 0.02, P < 0.05), whereas the number of Pax7(+) cells was unchanged in the leg muscles exposed to the NSAID (0.07 +/- 0.01). The number of inflammatory cells (CD68(+) or CD16(+) cells) was not significantly increased in either of the legs 8 days after exercise and was unaffected by the NSAID. The main finding in the present study was that the NSAID infusion for 7.5 h during the exercise day suppressed the exercise-induced increase in the number of satellite cells 8 days after exercise. These results suggest that NSAIDs negatively affect satellite cell activity after unaccustomed eccentric exercise.

Early and late rate of force development: differential adaptive responses to resistance training?

The objective of this study is to investigate the potentially opposing influence of qualitative and quantitative muscular adaptations in response to high-intensity resistance training on contractile rate of force development (RFD) in the early (<100 ms) and later phases (>200 ms) of rising muscle force. Fifteen healthy young males participated in a 14-week resistance training intervention for the lower body and 10 matched subjects participated as controls. Maximal muscle strength (MVC) and RFD were measured during maximal voluntary isometric contraction of the quadriceps femoris muscle. Muscle biopsies were obtained from the vastus lateralis. The main findings were that RFD in the late phase of rising muscle force increased in response to resistance training whereas early RFD remained unchanged and early relative RFD (i.e., RFD/MVC) decreased. Quantitatively, muscle fiber cross-sectional area and MVC increased whereas, qualitatively, the relative proportion of type IIX muscle fibers decreased. Multiple regression analysis showed that while increased MVC positively influenced both early and late RFD, decreased-type IIX negatively influenced early RFD only. In conclusion, early and late RFD responded differently to high-intensity resistance training due to differential influences of qualitative and quantitative muscular adaptations on early and later phases of rising muscle force.

Selective activation of neuromuscular compartments within the human trapezius muscle

Task-dependent differences in relative activity between "functional" subdivisions within human muscles are well documented. Contrary, independent voluntary control of anatomical subdivisions, termed neuromuscular compartments is not observed in human muscles. Therefore, the main aim of this study was to investigate whether subdivisions within the human trapezius can be independently activated by voluntary command using biofeedback guidance. Bipolar electromyographical electrodes were situated on four subdivisions of the trapezius muscle. The threshold for "active" and "rest" for each subdivision was set to >12% and <1.5% of the maximal electromyographical amplitude recorded during a maximal voluntary contraction. After 1h with biofeedback from each of the four trapezius subdivisions, 11 of 15 subjects learned selective activation of at least one of the four anatomical subdivisions of the trapezius muscle. All subjects managed to voluntarily activate the lower subdivisions independently from the upper subdivisions. Half of the subjects succeeded to voluntarily activate both upper subdivisions independently from the two lower subdivisions. These findings show that anatomical subdivisions of the human trapezius muscle can be independently activated by voluntary command, indicating neuromuscular compartmentalization of the trapezius muscle. The independent activation of the upper and lower subdivisions of the trapezius is in accordance with the selective innervation by the fine cranial and main branch of the accessory nerve to the upper and lower subdivisions. These findings provide new insight into motor control characteristics, learning possibilities, and function of the clinically relevant human trapezius muscle.

Muscle size, neuromuscular activation, and rapid force characteristics in elderly men and women: effects of unilateral long-term disuse due to hip-osteoarthritis

Substantial evidence exists for the age-related decline in muscle strength and neural function, but the effect of long-term disuse in the elderly is largely unexplored. The present study examined the effect of unilateral long-term limb disuse on maximal voluntary quadriceps contraction (MVC), lean quadriceps muscle cross-sectional area (LCSA), contractile rate of force development (RFD, Delta force/Delta time), impulse (integral force dt), muscle activation deficit (interpolated twitch technique), maximal neuromuscular activity [electromyogram (EMG)], and antagonist muscle coactivation in elderly men (M: 60-86 yr; n = 19) and women (W: 60-86 yr; n = 20) with unilateral chronic hip-osteoarthritis. Both sides were examined to compare the effect of long-term decreased activity on the affected (AF) leg with the unaffected (UN) side. AF had a significant lower MVC (W: 20%; M: 20%), LCSA (W: 8%; M: 10%), contractile RFD (W: 17-26%; M: 15-24%), impulse (W: 10-19%, M: 19-20%), maximal EMG amplitude (W: 22-25%, M: 22-28%), and an increased muscle activation deficit (-18%) compared with UN. Furthermore, women were less strong (AF: 40%; UN: 39%), had less muscle mass (AF: 33%; UN: 34%), and had a lower RFD (AF: 38-50%; UN: 41-48%) compared with men. Similarly, maximum EMG amplitude was smaller for both agonists (AF: 51-63%; UN: 35-61%) and antagonist (AF: 49-64%; UN: 36-56%) muscles in women compared with men. However, when MVC and RFD were normalized to LCSA, there were no differences between genders. The present data demonstrate that disuse leads to a marked loss of muscle strength and muscle mass in elderly individuals. Furthermore, the data indicate that neuromuscular activation and contractile RFD are more affected by long-term disuse than maximal muscle strength, which may increase the future risk for falls.

Resistance training and insulin action in humans: effects of de-training

Aerobic endurance training increases insulin action in skeletal muscle, but the effect of resistance training has not been well described. Controversy exists about whether the effect of resistance training is merely due to an increase in muscle mass. We studied the effect of cessation of resistance training in young, healthy subjects by taking muscle biopsies and measuring insulin-mediated whole body and leg glucose uptake rates after 90 days of heavy resistance training (T) and again after 90 days of de-training (dT). Data on leg glucose uptake were expressed relative to accurate measures of leg muscle mass by MRI scanning. Muscle strength (239 +/- 43 vs. 208 +/- 33 N m), quadriceps area (8463 +/- 453 vs. 7763 +/- 329 mm2) and glycogen content (458 +/- 22 vs. 400 +/- 26 mmol (kg dry weight muscle)(-1)) decreased, while myosin heavy chain isoform IIX increased 4-fold in dT vs. T, respectively (all P < 0.05). GLUT4 mRNA levels and enzyme activities and mRNA levels of glycolytic, lipolytic and glyconeogenic enzymes did not change with de-training. Likewise, capillary density did not change. Whole body glucose uptake decreased 11 % and leg glucose uptake decreased from 75 +/- 11 (T) to 50 +/- 6 (dT) nmol min(-1) (mm muscle)(-2) (P < 0.05) at maximal insulin, the latter decrease being due to decreased arterio-femoral venous glucose extraction. The decrease was mainly due to reduced non-oxidative glucose disposal. We have thus shown that 90 days after the termination of heavy resistance training, insulin-mediated glucose uptake rates per unit of skeletal muscle have decreased significantly.

Methylergometrine during the early puerperium; a prospective randomized double blind study

BACKGROUND

The purpose of the study was to determine the efficacy of 72-hour prophylactic oral methylergometrine in reducing postpartum hemorrhage and endometritis during the early puerperium, and the effect of methylergometrine on lochia and requests for analgesics.

MATERIAL AND METHODS

A prospective randomized double-blind study was undertaken; a total of 217 women received 0.2 mg methylergometrine intravenously after delivery of the placenta and randomized to either tabl. Methergin 0.125 mg or placebo three times a day for three days. The main measures were weight of sanitary towels, temperature, consumptions of analgesics and length of hospital stay.

RESULTS

We found no significant difference in the median amount of lochia, the need for analgesics or length of hospital stay between the two groups. Incidence of infection and postpartum hemorrhage were low in both groups.

CONCLUSION

We conclude that prophylactic use of methylergometrine during early puerperium has no effect on lochia. Endometritis and postpartum hemorrhage were rare in both groups. There was no increase in requests for analgesics among women given oral methylergometrine.

Levels of alpha2 pregnancy-associated glycoprotein in maternal circulation during pregnancy in the mink

This is the first demonstration of alpha 2-pregnancy-associated glycoprotein (alpha 2-PAG) in the mink. Mink alpha 2-PAG exhibits complete immunological cross reaction with dog alpha 2-PAG when analysed in assays employing antisera against canine alpha 2-PAG raised in rabbits. Alpha 2-PAG was quantitated by rocket immunoelectrophoresis in heparin plasma samples obtained from the peripheral circulation of mink during the breeding season. The plasma levels recorded in male mink were significantly lower (23 AU/ml) than the levels recorded in females at any stage of the breeding period. Very early in the breeding season and 2 weeks after delivery the alpha 2-PAG levels were high (> 200 AU/ml) in the circulation of the female mink. Like alpha 2-PAG in the pregnant bitch, mink alpha 2-PAG concentrations reach a local maximum in mid-pregnancy, and a local minimum at term.

Pregnancy-associated murine protein-1 plasma levels during oestrus cycle, pseudopregnancy and pregnancy in the mouse

A cyclic variation in plasma levels of pregnancy-associated murine protein-1 (PAMP-1) during the oestrus cycle in outbred Pan: Thei mice was recorded. PAMP-1 plasma levels were significantly elevated in dioestrus as compared with the three other stages of the murine oestrus cycle. Until day 7 of gestation the PAMP-1 plasma levels remained low, and no significant differences could be observed between pregnant and pseudopregnant female mice. The PAMP-1 levels increased markedly in the circulation on day 8 of pregnancy, and continued to increase until peak values were reached at day 11 of pregnancy. In the latter half of pregnancy the PAMP-1 levels declined until day 17 of pregnancy, at which stage the normal non-pregnant values were recorded.

Effect of extra-genital Schistosoma mansoni and Echinostoma caproni infections on serum levels of pregnancy-associated murine protein-1 during murine pregnancy

Maternal plasma levels of pregnancy-associated murine protein-1 (PAMP-1) were measured by rocket immunoelectrophoresis in BALB/cABom mice experimentally infected with the two intestinal parasites Schistosoma mansoni and Echinostoma caproni. In the first half of pregnancy the PAMP-1 level was significantly lower in the infected females compared with the healthy controls, indicating that PAMP-1 is not essential for implantation and early gestation. In the latter half of pregnancy a rapid increase in the plasma levels of PAMP-1 in the infected females was recorded. This might suggest that pituitary GH secretion is restored in the infected animals during the second half of gestation.

Monitoring of murine feto-placental growth by pregnancy-specific serum proteins in an experimentally induced fetal growth retardation model

Fetal growth retardation was induced in 14 day pregnant female mice by ligation of the uterine arteries. Maternal serum levels of pregnancy-associated murine protein-2 (PAM-2) and murine alpha-fetoprotein (m-AFP) were recorded. The ligation resulted in a reduction in fetal growth and a corresponding decrease in maternal circulatory m-AFP, whereas placental growth and maternal circulating PAM-2 were not significantly affected.