Related Articles

Rationale

Coffee is often consumed to counteract driver sleepiness. There is limited information on the effects of a single low dose of coffee on prolonged highway driving in non-sleep deprived individuals.

Objectives

The aim of this study was to examine the effects of a single cup of coffee (80 mg caffeine) on simulated highway driving performance.

Methods

Non-sleep deprived healthy volunteers (n = 24) participated in a double-blind, placebo-controlled, crossover study. After 2 h of monotonous highway driving, subjects received caffeinated or decaffeinated coffee during a 15-min break before continuing driving for another 2 h. The primary outcome measure was the standard deviation of lateral position (SDLP), reflecting the weaving of the car. Secondary outcome measures were speed variability, subjective sleepiness, and subjective driving performance.

Results

The results showed that caffeinated coffee significantly reduced SDLP as compared to decaffeinated coffee, both in the first (p = 0.024) and second hour (p = 0.019) after the break. Similarly, the standard deviation of speed (p = 0.024; p = 0.001), mental effort (p = 0.003; p = 0.023), and subjective sleepiness (p = 0.001; p = 0.002) were reduced in both the first and second hour after consuming caffeinated coffee. Subjective driving quality was significantly improved in the first hour after consuming caffeinated coffee (p = 0.004).

Conclusions

These findings demonstrate a positive effect of one cup of caffeinated coffee on driving performance and subjective sleepiness during monotonous simulated highway driving.

Aim:

To determine the anti-carious effect of coffee in humans. Coffee represents one of the most consumed products by the population.

Materials and Methods:

A random sample of 1000 individuals, of both sexes, who consumed only coffee as a beverage and who visited the Out-Patient Department of KLE Society's Institute of Dental Sciences, with a dental complaint and no history of any major illness, were considered as subjects. The patients' histories with regard to the coffee intake, such as, period of consumption, frequency of consumption, whether taken with milk or wihout milk, with sugar or without sugar, and the brand make, was noted. History of the type of diet, consumption of sweets, periodicity of brushing, and whether they had undergone fluoride applications were also noted. A thousand patients who consumed beverages other than coffee were taken as the control.

Results:

The results showed that coffee most consumed was roasted coffee, and the frequency on an average was about three cups per day, for an average period of 35 years. The Decayed/Missing/Filled Surface (DMFS) scores varied from 2.9, in subjects who drank black coffee, to 5.5 in subjects who consumed coffee together with sweeteners and creaming agents. The DMFS score was 3.4 in subjects who consumed coffee together with milk but no sugar. The DMFS score of the control subjects was 4, indicating that coffee if consumed alone had anticaries action, but in the presence of additives the antibacterial and anticaries action was totally minimized.

Conclusion:

Thus coffee can help in prevention of dental caries if consumed without additives.

Background

Coffee has been reported to lower levels of estrogen and insulin, two hormones implicated in endometrial carcinogenesis, but prospective data on the relation between coffee consumption and risk of endometrial cancer are limited.

Methods

We prospectively assessed coffee consumption in relation to endometrial cancer risk in the Nurses’ Health Study (NHS) with 67,470 female participants aged 34–59 in 1980. Cumulative average coffee intake was calculated with all available questionnaires to assess long-term effects. Cox regression models were used to calculate incidence rate ratios (RR), controlling for other risk factors.

Results

Fewer than 4 cups of coffee per day were not associated with endometrial cancer risk. However, women who consumed 4 or more cups of coffee had 25% lower risk of endometrial cancer than those who consumed less than 1 cup per day (multivariable RR=0.75; 95% CI =0.57–0.97; Ptrend = 0.02). We found the similar association with caffeinated coffee consumption (RR for ≥ 4 vs. <1 cup/day = 0.70; 95% CI = 0.51–0.95). For decaffeinated coffee consumption, a suggestive inverse association was found among women who consumed 2 or more cups per day vs. <1 cup/month. Tea consumption was not associated with endometrial cancer risk.

Conclusions

These prospective data suggest that 4 or more cups of coffee per day are associated with a lower risk of endometrial cancer.

Impact

Drinking of coffee, given its widespread consumption, might be an additional strategy to reduce endometrial cancer risk. However, addition of substantial sugar and cream to coffee could offset any potential benefits.

Background

Work-site strength training sessions are shown effective to prevent and reduce neck-shoulder pain in computer workers, but difficult to integrate in normal working routines. A solution for avoiding neck-shoulder pain during computer work may be to implement high intensity voluntary contractions during the computer work. However, it is unknown how this may influence productivity, rate of perceived exertion (RPE) as well as activity and rest of neck-shoulder muscles during computer work. The aim of this study was to investigate short-term effects of a high intensity contraction on productivity, RPE and upper trapezius activity and rest during computer work and a subsequent pause from computer work.

Methods

18 female computer workers performed 2 sessions of 15 min standardized computer mouse work preceded by 1 min pause with and without prior high intensity contraction of shoulder elevation. RPE was reported, productivity (drawings per min) measured, and bipolar surface electromyography (EMG) recorded from the dominant upper trapezius during pauses and sessions of computer work. Repeated measure ANOVA with Bonferroni corrected post-hoc tests was applied for the statistical analyses.

Results

The main findings were that a high intensity shoulder elevation did not modify RPE, productivity or EMG activity of the upper trapezius during the subsequent pause and computer work. However, the high intensity contraction reduced the relative rest time of the uppermost (clavicular) trapezius part during the subsequent pause from computer work (p < 0.04).

Conclusion

Since a preceding high intensity shoulder elevation did not impose a negative impact on perceived effort, productivity or upper trapezius activity during computer work, implementation of high intensity contraction during computer work to prevent neck-shoulder pain may be possible without affecting the working routines. However, the unexpected reduction in clavicular trapezius rest during a pause with preceding high intensity contraction requires further investigation before high intensity shoulder elevations can be recommended as an integrated part of computer work.

The acute effect of a single-dose of caffeine on the P300 event-related brain potential (ERP) was assessed in a study using a repeatedly presented auditory oddball button-press task. A dose (5mg/kg body-weight) of either caffeine or placebo lactose, dissolved in a cup of decaffeinated coffee, was administered double-blindly to coffee drinkers who had abstained from coffee for 24hrs, with the presentation order of the sessions counterbalanced and separated by 2–4 weeks. The caffeine-treatment condition demonstrated a smaller P300 amplitude and a shorter latency overall than the placebo treatment condition. The mean P300 amplitude value difference (caffeine minus placebo) increased with the successive trial blocks. Caffeine ingestion appears to yield a lower resource-consumption and a net increase in allocating attention resources for task performance across repeated measurements.

Objectives

To determine the effect of specific resistance training on forearm pain and work disability in industrial technicians.

Design and setting

Two-armed cluster randomised controlled trial of 20 weeks performed at two industrial production units in Copenhagen, Denmark.

Participants

Working-age industrial technicians both with and without pain and disability.

Interventions

The training group (n=282) performed specific resistance training for the shoulder, neck and arm muscles three times a week. The control group (n=255) was advised to continue normal physical activity.

Outcome

All participants rated forearm pain intensity (Visual Analogue Scale, 0–100 mm) once a week (primary outcome) and replied to a questionnaire on work disability (Disability of the Arm Shoulder and Hand, 0–100) at baseline and follow-up (secondary outcome).

Results

Questionnaires were sent to 854 workers of which 30 (n=282) and 27 (n=255) clusters were randomised to training and control, respectively. Of these, 211 and 237 participants, respectively, responded to the follow-up questionnaire. Intention-to-treat analyses including both individuals with and without pain showed that from baseline to follow-up, pain intensity and work disability decreased more in the training group than in the control group (4–5 on a scale of 0–100, p<0.01–0.001). Among those with pain >30 mm Visual Analogue Scale at baseline (n=54), the OR for complete recovery at follow-up in the training group compared with the control group was 4.6 (95% CI 1.2 to 17.9). Among those with work disability >30 at baseline (n=113), the OR for complete recovery at follow-up in the training group compared with the control group was 6.0 (95% CI 1.8 to 19.8).

Conclusion

Specific resistance training of the shoulder, neck and arm reduces forearm pain and work disability among industrial technicians.

Trial registration number

NCT01071980.

Article summary

Article focus

Forearm pain is associated with work disability and healthcare costs.

Specific resistance training effectively reduces neck and shoulder pain, but its effect on forearm pain is only scarcely investigated.

Our study determines the effect of specific resistance training on forearm pain and work disability in industrial technicians.

Key message

Specific resistance training of the shoulder, neck and arm reduces forearm pain and work disability among industrial technicians.

Strengths and limitations of this study

The cluster randomised controlled design with high statistical power strengthens our study.

As we included both public and private sector companies of which most of the invited employees agreed to participate, the external validity of our findings is high.

The inclusion and exclusion criteria limit the generalisability to technicians with non-specific forearm pain.

A limitation is the loss to follow-up of more than 20% of the participants in the training group.

Objective: To investigate the effects of ambulant myofeedback training including ergonomic counselling (Mfb) and ergonomic counselling alone (EC), on work-related neck-shoulder pain and disability. Methods: Seventy-nine female computer workers reporting neck-shoulder complaints were randomly assigned to Mfb or EC and received four weeks of intervention. Pain intensity in neck, shoulders, and upper back, and pain disability, were measured at baseline, immediately after intervention, and at three and six months follow-up. Results: Pain intensity and disability had significantly decreased immediately after four weeks Mfb or EC, and the effects remained at follow up. No differences were observed between the Mfb and EC group for outcome and subjects in both intervention groups showed comparable chances for improvement in pain intensity and disability. Conclusions: Pain intensity and disability significantly reduced after both interventions and this effect remained at follow-up. No differences were observed between the two intervention groups.

Background

This review examines the evidence for an association between computer work and neck and upper extremity disorders (except carpal tunnel syndrome).

Methods

A systematic critical review of studies of computer work and musculoskeletal disorders verified by a physical examination was performed.

Results

A total of 22 studies (26 articles) fulfilled the inclusion criteria. Results show limited evidence for a causal relationship between computer work per se, computer mouse and keyboard time related to a diagnosis of wrist tendonitis, and for an association between computer mouse time and forearm disorders. Limited evidence was also found for a causal relationship between computer work per se and computer mouse time related to tension neck syndrome, but the evidence for keyboard time was insufficient. Insufficient evidence was found for an association between other musculoskeletal diagnoses of the neck and upper extremities, including shoulder tendonitis and epicondylitis, and any aspect of computer work.

Conclusions

There is limited epidemiological evidence for an association between aspects of computer work and some of the clinical diagnoses studied. None of the evidence was considered as moderate or strong and there is a need for more and better documentation.

In a residential research ward coffee drinking was studied in 9 volunteer human subjects with histories of heavy coffee drinking. A series of five experiments was undertaken to characterize adlibitum coffee consumption and to investigate the effects of manipulating coffee concentration, caffeine dose per cup, and caffeine preloads prior to coffee drinking. Manipulations were double-blind and scheduled in randomized sequences across days. When cups of coffee were freely available, coffee drinking tended to be rather regularly spaced during the day with intercup intervals becoming progressively longer throughout the day; experimental manipulations showed that this lengthening of intercup intervals was not due to accumulating caffeine levels. Number of cups of coffee consumed was an inverted U-shaped function of both coffee concentration and caffeine dose per cup; however, coffee-concentration and dose-per-cup manipulations did not produce similar effects on other measures of coffee drinking (intercup interval, time to drink a cup, within-day distribution of cups). Caffeine preload produced dose-related decreases in number of cups consumed. As a whole, these experiments provide some limited evidence for both the suppressive and the reinforcing effects of caffeine on coffee consumption. Examination of total daily coffee and caffeine intake across experiments, however, provides no evidence for precise regulation (i.e., titration) of coffee or caffeine intake.

Background

Specific strength training can reduce neck and shoulder pain in office workers, but the optimal combination of exercise frequency and duration remains unknown. This study investigates how one weekly hour of strength training for the neck and shoulder muscles is most effectively distributed.

Methods

A total of 447 office workers with and without neck and/or shoulder pain were randomly allocated at the cluster-level to one of four groups; 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). Primary outcome was self-reported neck and shoulder pain (scale 0–9) and secondary outcome work disability (Disability in Arms, Shoulders and Hands (DASH)).

Results

The intention-to-treat analysis showed reduced neck and right shoulder pain in the training groups after 20 weeks compared with REF. Among those with pain ≥3 at baseline (n=256), all three training groups achieved significant reduction in neck pain compared with REF (p<0.01). From a baseline pain rating of 3.2 (SD 2.3) in the neck among neck cases, 1WS experienced a reduction of 1.14 (95% CI 0.17 to 2.10), 3WS 1.88 (0.90 to 2.87) and 9WS 1.35 (0.24 to 2.46) which is considered clinically significant. DASH was reduced in 1WS and 3WS only.

Conclusion

One hour of specific strength training effectively reduced neck and shoulder pain in office workers. Although the three contrasting training groups showed no statistical differences in neck pain reduction, only 1WS and 3WS reduced DASH. This study suggests some flexibility regarding time-wise distribution when implementing specific strength training at the workplace.

Respiratory symptoms and lung function were studied in nine coffee workers who complained of job related respiratory symptoms. Six described symptoms characteristic of occupational asthma. Lung function data showed obstructive changes mostly in the smaller airways with no impairment in diffusing capacity. Bronchoprovocation testing with green coffee allergen provoked immediate asthmatic reactions with acute reductions of ventilatory capacity in four workers. The relative fall in FEF25-75% (ranging from 28% to 66%) was greater than in FEV1 (ranging from 18% to 62% of the control values). Eight of the nine workers had an increased total IgE serum level; five had positive intradermal skin tests to green coffee allergen. Most of the six healthy subjects experimentally exposed to green coffee dust in the working environment showed an acute fall in flow rates on maximum expiratory flow-volume curves. These results indicate that bronchoprovocation with green coffee allergen or green coffee dust may be used to identify subjects sensitive to green coffee.

In a controlled trial to evaluate the effectiveness of a simple educational and physical program administered to a large cohort of public servants, we previously found that 6 months following treatment the monthly frequency of headache and neck and shoulder pain and drug intake was reduced by 40% in the experimental compared with controls. These results were stable at a 12-month follow up. The program consists of brief shoulder and neck exercises to be performed several times a day, a relaxation exercise, and instructions on how to reduce parafunction and hyperfunction of the craniofacial and neck muscles during the day. The purpose of this work was to investigate whether the data previously obtained could be confirmed also in the group of 192 subjects that served as controls in first phase of the study and received the intervention in the second phase of the study. The primary endpoint was the change in frequency of headache and neck and shoulder pain expressed as the number of days per month with pain, and as the proportion of subjects with a ≥50% reduction of frequency (responder rate) at the last 2 months of the 6-month intervention period compared to the 2 months preceding the intervention (baseline). The number of days of analgesic drug consumption was also recorded. Days per month with headache at the baseline and at the end of intervention period were 6.40 and 4.58 (mean change −1.81, p < 0.0001), respectively; days with neck and shoulder pain were 7.48 and 6.18 (mean change −1.30, p = 0.0179); days of analgesic consumption were 1.67 and 1.17 (mean change −0.50, p = 0.0222). The responder rate was 42.3% for headache, 42% for neck and shoulder pain and 58.3% for drug consumption. In conclusion, this study adds further evidence on the efficacy of our program and its high acceptability in a large, unselected, working population.

In a 10 week trial to assess the effects of coffee consumption and coffee brewing methods on serum cholesterol concentrations 33 men with hypercholesterolaemia were randomly assigned to: continue with their usual coffee intake; stop drinking coffee altogether; or stop drinking coffee for five weeks, thereafter drinking either boiled or filter coffee. Cholesterol concentrations fell significantly in all subjects abstaining for the first five weeks compared with subjects not giving up and continued to fall in those abstaining for 10 weeks. Cholesterol concentrations rose again in subjects returning to boiled coffee but remained the same in those returning to filter coffee. Abstention from heavy coffee drinking is an efficient way of reducing serum cholesterol concentrations in men with hypercholesterolaemia. The extent to which the brewing method affects this relation requires further study.

Images

Background

Call centre work with computers is associated with increased rates of upper body pain and musculoskeletal disorders.

Methods

This one year, randomised controlled intervention trial evaluated the effects of a wide forearm support surface and a trackball on upper body pain severity and incident musculoskeletal disorders among 182 call centre operators at a large healthcare company. Participants were randomised to receive (1) ergonomics training only, (2) training plus a trackball, (3) training plus a forearm support, or (4) training plus a trackball and forearm support. Outcome measures were weekly pain severity scores and diagnosis of incident musculoskeletal disorder in the upper extremities or the neck/shoulder region based on physical examination performed by a physician blinded to intervention. Analyses using Cox proportional hazard models and linear regression models adjusted for demographic factors, baseline pain levels, and psychosocial job factors.

Results

Post‐intervention, 63 participants were diagnosed with one or more incident musculoskeletal disorders. Hazard rate ratios showed a protective effect of the armboard for neck/shoulder disorders (HR = 0.49, 95% CI 0.24 to 0.97) after adjusting for baseline pain levels and demographic and psychosocial factors. The armboard also significantly reduced neck/shoulder pain (p = 0.01) and right upper extremity pain (p = 0.002) in comparison to the control group. A return‐on‐investment model predicted a full return of armboard and installation costs within 10.6 months.

Conclusion

Providing a large forearm support combined with ergonomic training is an effective intervention to prevent upper body musculoskeletal disorders and reduce upper body pain associated with computer work among call centre employees.

OBJECTIVES—To determine the influence of short term exposure to mechanical factors on regional musculoskeletal pain.
METHODS—Full time newly employed workers were recruited from 12 occupational groups and information collected by questionnaire. Subjects indicated on a blank body manikin any low back, shoulder, wrist or forearm or both, or knee pain which had occurred during the past month and had lasted more than 1 day. Data were also collected with a previously validated questionnaire on working postures, manual handling activities, and repetitive movements of the upper limb. The relations between mechanical factors and each area of pain were calculated as odds ratios (ORs) with 95% confidence intervals (95% CIs). Adjustment was made for age and sex.
RESULTS—1081 subjects (median age 23; interquartile range 20-27) were recruited to the study (a participation rate of 91%). 261 (24%) reported low back pain, 221 (20%) shoulder pain, 93 (9%) wrist or forearm pain, and 222 (21%) knee pain. Several specific manual handling activities were found to be associated with low back, shoulder, and knee pain. Carrying weights of more than 50 lbs (23 kg) on one shoulder was the factor which was most strongly associated with low back pain (OR 2.4 (95% CI 1.5 to 3.8)), shoulder pain (OR 3.1 (95% CI 1.9 to 4.8)), and knee pain (OR 3.5 (95% CI 2.2 to 5.5)), whereas forearm pain was most strongly associated with repetitive movements of the wrists (OR 1.8 (95% CI 1.04 to 3.1)). By contrast very few postures were associated with regional pain, although bending forwards in an uncomfortable position for at least 15 minutes was associated with shoulder pain (OR 1.6 (95% CI 1.2 to 2.2)) and kneeling for at least 15 minutes was associated with knee pain (OR 1.8 (95% CI 1.2 to 2.6)). Exposure to mechanical factors was most strongly associated with pain at multiple sites rather than with pains in individual regions.
CONCLUSIONS—Even among workers with only short term exposure to mechanical factors, musculoskeletal pain is increased.


Keywords: epidemiology; manual handling; questionnaire

Introduction This study aims to investigate the relationship between work-related physical and psychosocial characteristics and complaints of the neck, shoulder and forearm/hands. Methods Data were used from a prospective Dutch cohort study among computer office workers with a follow-up period of 2 years. The study was conducted among 264 computer users. Physical and psychosocial risk factors were tested to predict the occurrence of neck, shoulder and forearm/hands complaints. Bivariate and multivariable logistic regression was used to identify the association between risk factors and outcome variables. Results The 2 year follow-up prevalence rates with 95% CI for neck complaints were 0.31 (0.28–0.37), for shoulder complaints 0.33 (0.27–0.39) and for forearm/hands complaints 0.21 (0.14–0.28). Four main predictors for the occurrence of neck and shoulder complaints were identified: (1) Irregular head and body posture [OR: 1.1 (1.0–1.2) P = 0.04]; (2) task difficulty (job demands) [OR: 1.2 (1.0–1.5) P = 0.01]; (3) number of working hours/day with the computer [OR: 1.20 (1.0–1.4) P = 0.03]; and (4) having had a previous history of complaints [OR: 7.2 (3.8–13.2) P = 0.01]. Two predictors were identified for forearm/hands complaints: time pressure (job demands) [OR: 1.20 (1.0–1.4) P = 0.03] and having had a previous history of complaints [OR: 7.1 (3.5–14.1) P = 0.06]. Conclusion This longitudinal study suggests that risk factors of upper musculoskeletal complaints in computer workers consist of a mixture of physical and psychosocial characteristics.

Abstract

Objective

This pilot project investigates the effectiveness of the Toftness system of chiropractic adjusting on subjects with pain syndromes.

Methods

Patients were recruited from 13 doctors' offices. All subjects received Toftness chiropractic adjustments. The visual analog scale (VAS) and Oswestry low back pain questionnaire were used for all subjects before and after chiropractic adjustments.

Results

A total of 42 patients were recruited. Twenty-eight patients had acute or chronic back pain and 14 experienced other types of pain (eg, neck pain, knee pain, shoulder pain, etc). The average age of the patient population (18 male, 24 female) was 53 ± 16 years. After 6 to 8 weeks of chiropractic adjustments, pain as analyzed using the visual analog scale was reduced significantly from 73.6 ± 12.790 to 17.0 ± 13.363 (P < .001). The Oswestry score decreased significantly from 69.3 ± 18.525 to 12.4 ± 10.504 (P < .001). There were no adverse treatment effects reported by the participating patients.

Conclusion

The Toftness system of chiropractic adjusting reduced low back and other pain syndromes in the subjects studied. It suggests that the Toftness system of chiropractic adjusting was safe and effective to use in low back pain and other pain-related conditions.

Background

Neck and shoulder complaints are common among employees in sedentary occupations characterized by intensive computer use. Such musculoskeletal pain - which is often associated with restricted range of motion and loss of muscle strength - is one of the most common conditions treated by physical therapists. The exact mechanism of neck pain is rarely revealed by clinical examination and the treatment has varied from passive rest to active treatments. Active treatments have often been divided into either training of the painful area or the surrounding musculature avoiding direct training of the painful area. Our study investigates the effect of the latter approach.

Methods/Design

A randomized controlled trial of 10 weeks duration is currently being conducted. Employed office workers with severe neck-shoulder pain are randomized to 3 × 20 min shoulder function training with training supervision or to a reference group receiving advice to stay physically active. Shoulder function training primarily focuses on the serratus anterior and lower trapezius muscle with only minimal activation the upper trapezius.

An announcement was sent to the administrative section of the university including jobs characterized by intensive computer work. The first 100 positive replies entered the study. Among these inclusion criteria were pain intensity in the neck/shoulder of at least 3 on a 0-9 scale. Exclusion criteria were cardiovascular disease, trauma, hypertension, or serious chronic disease. Before and after the intervention period the participants replied to a questionnaire about musculoskeletal disorders and work disability, and underwent a standardized clinical examination of the neck and shoulder girdle. Further, on a weekly basis the participants log pain intensity of the neck and shoulder during the previous week.

The primary outcome measure is pain in the neck and shoulders at week 10 based on the weekly pain registration and results from the clinical examination. Secondary outcomes are strength and work disability.

Trial Registration

ClinicalTrials (NCT): NCT01205542

Mental motor imagery is subserved by the same cognitive systems that underlie action. In turn, action is informed by the anticipated sensory consequences of movement, including pain. In light of these considerations, one would predict that motor imagery would provide a useful measure pain-related functional interference. We report a study in which 19 patients with chronic musculoskeletal or radiculopathic arm or shoulder pain, 24 subjects with chronic pain not involving the arm/shoulder and 41 normal controls were asked to indicate if a line drawing was a right or left hand. Previous work demonstrated that this task is performed by mental rotation of the subject’s hand to match the stimulus. Relative to normal and pain control subjects, arm/shoulder pain subjects were significantly slower for stimuli that required greater amplitude rotations. For the arm/shoulder pain subjects only there was a correlation between degree of slowing and the rating of severity of pain with movement but not the non-specific pain rating. The hand laterality task may supplement the assessment of subjects with chronic arm/shoulder pain.

Methods: A total of 6943 participants with a wide range of computer use and work tasks were studied. At baseline and at one year follow up participants completed a questionnaire. Participants with relevant forearm symptoms were offered a clinical examination. Symptom cases and clinical cases were defined on the basis of self reported pain score and palpation tenderness in the muscles of the forearm.

Results: The seven days prevalence of moderate to severe forearm pain was 4.3%. Sixteen of 296 symptom cases met criteria for being a clinical forearm case, and 12 had signs of potential nerve entrapment. One year incidence of reported symptom cases was 1.3%; no subjects developed new signs of nerve entrapment. Increased risk of new forearm pain was associated with use of a mouse device for more than 30 hours per week, and with keyboard use more than 15 hours per week. High job demands and time pressure at baseline were risk factors for onset of forearm pain; women had a twofold increased risk of developing forearm pain. Self reported ergonomic workplace factors at baseline did not predict future forearm pain.

Conclusion: Intensive use of a mouse device, and to a lesser extent keyboard usage, were the main risk factors for forearm pain. The occurrence of clinical disorders was low, suggesting that computer use is not commonly associated with any severe occupational hazard to the forearm.

Background

Sympathetic nervous activity contributes to the maintenance of muscle oxygenation. However, patients with chronic pain may suffer from autonomic dysfunction. Furthermore, insufficient muscle oxygenation is observed among workers with chronic neck and shoulder pain. The aim of our study was to investigate how muscle load tasks affect sympathetic nervous activity and changes in oxygenation of the trapezius muscles in subjects with chronic neck and shoulder pain.

Methods

Thirty females were assigned to two groups: a pain group consisting of subjects with chronic neck and shoulder pain and a control group consisting of asymptomatic subjects. The participants performed three sets of isometric exercise in an upright position; they contracted their trapezius muscles with maximum effort and let the muscles relax (Relax). Autonomic nervous activity and oxygenation of the trapezius muscles were measured by heart rate variability (HRV) and Near-Infrared Spectroscopy.

Results

Oxyhemoglobin and total hemoglobin of the trapezius muscles in the pain group were lower during the Relax period compared with the control group. In addition, the low frequency / high frequency (LF/HF) ratio of HRV significantly increased during isometric exercise in the control group, whereas there were no significant changes in the pain group.

Conclusions

Subjects with neck and shoulder pain showed lower oxygenation and blood flow of the trapezius muscles responding to isometric exercise, compared with asymptomatic subjects. Subjects with neck and shoulder pain also showed no significant changes in the LF/HF ratio of HRV responding to isometric exercise, which would imply a reduction in sympathetic nervous activity.

Background

Coffee consumption has been associated with a lower risk of type 2 diabetes in prospective cohort studies, but the underlying mechanisms remain unclear. The aim of this study was to evaluate the effects of regular and decaffeinated coffee on biological risk factors for type 2 diabetes.

Methods

Randomized parallel-arm intervention conducted in 45 healthy overweight volunteers who were nonsmokers and regular coffee consumers. Participants were assigned to consumption of 5 cups (177 mL each) per day of instant caffeinated coffee, decaffeinated coffee, or no coffee (i.e., water) for 8 weeks.

Results

Average age was 40 years and body mass index was 29.5 kg/m2. Compared with consuming no coffee, consumption of caffeinated coffee increased adiponectin (difference in change from baseline 1.4 μg/mL; 95% CI: 0.2, 2.7) and interleukin-6 (difference: 60%; 95% CI: 8, 138) concentrations and consumption of decaffeinated coffee decreased fetuin-A concentrations (difference: -20%; 95% CI: -35, -1). For measures of glucose tolerance, insulin sensitivity, and insulin secretion, no significant differences were found between treatment groups.

Conclusions

Although no changes in glycemia and/or insulin sensitivity were observed after 8 weeks of coffee consumption, improvements in adipocyte and liver function as indicated by changes in adiponectin and fetuin-A concentrations may contribute to beneficial metabolic effects of long-term coffee consumption.

Trial Registration

clinicaltrials.gov NCT00305097

Objectives

Musculoskeletal pain is associated with occupational physical activities and psychosocial risk factors. We evaluated the relative importance of work-related and psychological determinants of the number of anatomical sites affected by musculoskeletal pain in a cross-sectional survey.

Methods

The survey focused on musculoskeletal pain in six body regions (low-back, neck, shoulder, elbow, wrist/hand and knee) among 224 nurses, 200 office workers and 140 postal clerks in Crete (response rate 95%). Information was collected about demographic characteristics, occupational physical load, psychosocial aspects of work, perceptions about causes of pain, mental health, tendency to somatize, and experience of pain in the past 12 months. Poisson regression was used to assess associations of risk factors with the number of painful anatomical sites and interactions were explored using classification and regression trees (CART).

Results

Two-thirds of the study sample reported pain in at least two body sites during the past 12 months, and in 23%, more than three sites were affected. The number of painful anatomical sites was strongly related to both physical load at work and somatizing tendency (with relative risks increased five-fold or more for frequent and disabling multisite pain) , and was also significantly associated with work-related psychosocial factors, and beliefs about work causation. The CART analysis suggested that in the population studied, the leading determinant of the number of painful body sites was somatizing tendency.

Conclusions

In the population studied, pain at multiple anatomical sites is common, and is strongly associated with somatizing tendency, which may have a more important influence on multi-site pain than on pain that is limited to a single anatomical site.

This paper summarizes the current epidemiological evidence on coffee consumption in relation to blood pressure (BP) and risk of hypertension. Data from cross-sectional studies suggest an inverse linear or U-shaped association of habitual coffee use with BP in different populations. Prospective studies suggest a protective effect of high coffee intake (4 or more cups per day) against hypertension, mainly in women. Furthermore, the risk of hypertension may be lower in coffee abstainers. Randomized controlled trials, which are mostly of short duration (1–12 weeks), have shown that coffee intake around 5 cups per day causes a small elevation in BP (∼2/1 mmHg) when compared to abstinence or use of decaffeinated coffee. With regard to underlying biological mechanisms, most research has been devoted to BP-raising effects of caffeine. However, there are many other substances in coffee, such as polyphenols, soluble fibre and potassium, which could exert a beneficial effect in the cardiovascular system. Although the precise nature of the relation between coffee and BP is still unclear, most evidence suggests that regular intake of caffeinated coffee does not increase the risk of hypertension.

Background

Neck-shoulder pain conditions, e.g., chronic trapezius myalgia, have been associated with sensory disturbances such as increased sensitivity to experimentally induced pain. This study investigated pain sensitivity in terms of bilateral pressure pain thresholds over the trapezius and tibialis anterior muscles and pain responses after a unilateral hypertonic saline infusion into the right legs tibialis anterior muscle and related those parameters to intensity and area size of the clinical pain and to psychological factors (sleeping problems, depression, anxiety, catastrophizing and fear-avoidance).

Methods

Nineteen women with chronic non-traumatic neck-shoulder pain but without simultaneous anatomically widespread clinical pain (NSP) and 30 age-matched pain-free female control subjects (CON) participated in the study.

Results

NSP had lower pressure pain thresholds over the trapezius and over the tibialis anterior muscles and experienced hypertonic saline-evoked pain in the tibialis anterior muscle to be significantly more intense and locally more widespread than CON. More intense symptoms of anxiety and depression together with a higher disability level were associated with increased pain responses to experimental pain induction and a larger area size of the clinical neck-shoulder pain at its worst.

Conclusion

These results indicate that central mechanisms e.g., central sensitization and altered descending control, are involved in chronic neck-shoulder pain since sensory hypersensitivity was found in areas distant to the site of clinical pain. Psychological status was found to interact with the perception, intensity, duration and distribution of induced pain (hypertonic saline) together with the spreading of clinical pain. The duration and intensity of pain correlated negatively with pressure pain thresholds.