Trends in Work-Related Musculoskeletal Disorders From the 2002 to 2014 General Social Survey, Quality of Work Life Supplement.

OBJECTIVE: To update trends in prevalence of back and upper limb musculoskeletal symptoms and risk factors from the 2014 Quality of Work Life (QWL) Survey. METHODS: Quadrennial QWL Surveys, 2002 to 2014 (with N = 1455, 1537, 1019, and 1124 in 2002, 2006, 2010, and 2014 surveys respectively) were analyzed for reports of back pain and pain in arms. RESULTS: In the fourth analysis of this survey, 12-year trends continue to show a decline in back pain and pain in arms. Key physical (heavy lifting, hand movements, very hard physical effort) and psychosocial/work organizational factors (low supervisor support, work is always stressful, not enough time to get work done) remain associated with back and arm pain, with the physical risk factors showing the strongest associations. CONCLUSION: Physical exposure risk factors continue to be strongly associated with low back and arm pain and should be the focus of intervention strategies.

Further Trends in Work-Related Musculoskeletal Disorders: A Comparison of Risk Factors for Symptoms Using Quality of Work Life Data From the 2002, 2006, and 2010 General Social Survey.

OBJECTIVE: To report trends for the risk of musculoskeletal disorders. METHODS: Three Quality of Work Life surveys examine the risk factors for musculoskeletal disorders. RESULTS: Findings similar for several risk factors, but differences across the reporting years may reflect economic conditions. Respondent numbers in 2010 were reduced, some risk factors had pattern changes, and there were sex and age differences. Trend analysis showed most significant changes were for the "work fast" risk factor. New 2010 "physical effort" item showed sex differences, and items reflective of total worker health showed strong associations with "back pain" and "pain in arms." CONCLUSIONS: Intervention strategies should focus on physical exposures and psychosocial risk factors (work stress, safety climate, job satisfaction, supervisor support, work fast, work freedom, work time) that have been consistently related to reports of musculoskeletal disorders. Economic conditions will influence some psychosocial risk factors.

Evidence of health risks associated with prolonged standing at work and intervention effectiveness.

PURPOSE: Prolonged standing at work has been shown to be associated with a number of potentially serious health outcomes, such as lower back and leg pain, cardiovascular problems, fatigue, discomfort, and pregnancy-related health outcomes. Recent studies have been conducted examining the relationship between these health outcomes and the amount of time spent standing while on the job. The purpose of this article was to provide a review of the health risks and interventions for workers and employers that are involved in occupations requiring prolonged standing. A brief review of recommendations by governmental and professional organizations for hours of prolonged standing is also included. FINDINGS: Based on our review of the literature, there seems to be ample evidence showing that prolonged standing at work leads to adverse health outcomes. Review of the literature also supports the conclusion that certain interventions are effective in reducing the hazards associated with prolonged standing. Suggested interventions include the use of floor mats, sit-stand workstations/chairs, shoes, shoe inserts and hosiery or stockings. Studies could be improved by using more precise definitions of prolonged standing (e.g., duration, movement restrictions, and type of work), better measurement of the health outcomes, and more rigorous study protocols. CONCLUSION AND CLINICAL RELEVANCE: Use of interventions and following suggested guidelines on hours of standing from governmental and professional organizations should reduce the health risks from prolonged standing.

Workplace exercise for control of occupational neck/shoulder disorders: a review of prospective studies.

A review was conducted of prospective studies (1997-2014) examining the efficacy of exercise as a workplace intervention to control neck/shoulder pain, symptoms, and disability. The review identified 38 relevant studies - 20 were classified with positive effects, 13 with null effects, and 5 as inconclusive. Of the positive studies, 12 were consistent with Level I evidence, 3 with Level II evidence, and 5 with Level IV evidence. Specific resistance training (SRT) exercise appeared to be associated with more positive studies (eight Level I studies) than other exercise modalities such as general resistance training, general physical exercise, stretching, and movement awareness exercises. Studies of longer trial duration tended toward more null findings and lower program compliance. Evidence for a primary preventive effect of workplace exercise is minimal. The findings of this review suggest that workplace exercise can be effective as tertiary prevention and therapeutic relief of neck/shoulder symptoms, at least over the shorter term.

Trends in work-related musculoskeletal disorders: a comparison of risk factors for symptoms using quality of work life data from the 2002 and 2006 general social survey.

OBJECTIVE: To assess trends in risk factors for work-related musculoskeletal disorders (MSDs). METHODS: Results from two similar national surveys (2002 and 2006) examined trends in relationships between individual, psychosocial, and physical factors and MSDs. RESULTS: Findings between years were similar, but important differences included a stronger effect of "Work Stress" on "Pain in Arms," and a stronger combined effect of "Hand Movement" and "Work Stress" on "Pain in Arms." Also, two interactions were statistically significant in the 2006 data, but not in the 2002 data, revealing potentially increased risks. These were "Hand Movement" and "Work Stress" on "Back Pain," and "Heavy Lifting" and "Work Stress" on "Pain in Arms." CONCLUSION: New strategies for preventing both low back and upper extremity MSDs should focus on work stress, heavy lifting, and hand movement, individually and in combination.

Treatment of primary biliary cirrhosis with tetrathiomolybdate: results of a double-blind trial.

The results of a double-blind trial of tetrathiomolybdate therapy and standard of care, versus placebo and standard of care treatment, in primary biliary cirrhosis patients are presented. Baseline studies of liver function, various safety variables, ceruloplasmin, a liver biopsy for histologic analysis, and for various cytokine analyses were carried out. Patients were observed every 4 months for up to 2 years of treatment by a hepatologist for clinical evaluation and repeat of all the baseline studies except liver biopsy, which was repeated at 2 years. The primary end points were improvement in 2 liver function tests and in 1 inflammatory cytokine. Fifteen placebo patients were followed for an average of 13 months, and 13 tetrathiomolybdate patients were followed for an average of 14 months. The predefined primary end points for efficacy were met. Tetrathiomolybdate was well tolerated. Because tetrathiomolybdate has been shown in numerous animal studies to inhibit autoimmune and inflammatory processes, and because primary biliary cirrhosis is an autoimmune attack on bile ducts, these positive findings on efficacy of tetrathiomolybdate therapy in primary biliary cirrhosis fit with the animal studies and suggest the need for a longer clinical trial to examine transplant-free survival.

Treatment of Wilson's disease with tetrathiomolybdate: V. Control of free copper by tetrathiomolybdate and a comparison with trientine.

It has become clear that serum "free" copper (the copper not bound to ceruloplasmin in the blood) is the copper causing copper toxicity in Wilson's disease. But up until now, free copper has not been closely followed during initiation of anticopper therapy in neurologically presenting patients. During this period of initial therapy, the future fate of these patients hangs in the balance-if they worsen neurologically as often happens with penicillamine or trientine therapy, many never recover. We hypothesize that free copper levels are a biological marker of clinical outcome in these patients. In this article, we evaluate the control of free copper in 3 studies of initial anticopper treatment in neurologically presenting Wilson's disease patients. The first (study 1) is a 55-patient open-label trial of tetrathiomolybdate, the second (study 2) is a 48-patient double-blind trial comparing tetrathiomolybdate and trientine, and the third (study 3) is a 40-patient double-blind comparison of 2 disease regimens of tetrathiomolybdate. Free copper levels were determined by subtracting ceruloplasmin and tetrathiomolybdate bound copper from total serum copper. Tetrathiomolybdate showed very strong control of free copper levels over the 8 weeks of treatment in the 55-patient open-label study (study 1), reducing it to a mean value of about one fourth, or less, of baseline. In the tetrathiomolybdate/trientine double blind (study 2), tetrathiomolybdate again showed good control of free copper levels over 8 weeks of treatment, which is significantly better than trientine. In the trientine arm of study 2, mean free copper levels actually went up during trientine therapy. The 5 patients who neurologically worsened on trientine therapy over 8 weeks of treatment showed significant spikes in serum free copper levels associated in time with their neurologic worsening. Patients who did not worsen neurologically generally did not show significant spikes in free copper. Tetrathiomolybdate controlled copper less well in the dose regimen study (study 3) than in the previous 2 studies of tetrathiomolybdate treatment, probably because of a change in the way "away from food" tetrathiomolybdate was given.

A cross-sectional study of risk factors for musculoskeletal symptoms in the workplace using data from the General Social Survey (GSS).

OBJECTIVE: Assessments of potential risk factors for musculoskeletal disorders (MSDs) from large, national study populations using personal interviews are critical to our understanding of exposure-response relationships. To address this need, we analyzed two outcome measures--self-reported back pain and upper extremity pain--from the quality of work life (QWL) module of the General Social Survey (GSS). We investigated several individual, psychosocial, and physical factors for their relationship to these outcome measures. METHODS: The study population included US adults, noninstitutionalized, English-speaking, aged 18 years or older, and employed at least part time (>or=20 hr/wk). Final sample size was 1484 workers. RESULTS: Variables of physical exposure significantly increased the risk of both low back pain and upper extremity pain. Multiple injuries and some psychosocial factors were associated with MSDs, and there was an additive effect on risk of MSDs with exposure to both physical exposure and work stress. CONCLUSIONS: A relationship between physical loads and musculoskeletal disorders was indicated by the results, which will enable creating a database for tracking reports of MSDs in the US working population.

Treatment of Wilson disease with ammonium tetrathiomolybdate: IV. Comparison of tetrathiomolybdate and trientine in a double-blind study of treatment of the neurologic presentation of Wilson disease.

OBJECTIVE: To compare tetrathiomolybdate and trientine in treating patients with the neurologic presentation of Wilson disease for the frequency of neurologic worsening, adverse effects, and degree of neurologic recovery. DESIGN: A randomized, double-blind, controlled, 2-arm study of 48 patients with the neurologic presentation of Wilson disease. Patients either received 500 mg of trientine hydrochloride 2 times per day or 20 mg of tetrathiomolybdate 3 times per day with meals and 20 mg 3 times per day between meals for 8 weeks. All patients received 50 mg of zinc 2 times per day. Patients were hospitalized for 8 weeks, with neurologic and speech function assessed weekly; discharged taking 50 mg of zinc 3 times per day, and returned annually for follow-up. SETTING: A university hospital referral setting. PATIENTS: Primarily newly diagnosed patients with Wilson disease presenting with neurologic symptoms who had not been treated longer than 4 weeks with an anticopper drug. INTERVENTION: Treatment with either trientine plus zinc or tetrathiomolybdate plus zinc. MAIN OUTCOME MEASURES: Neurologic function was assessed by semiquantitative neurologic and speech examinations. Drug adverse events were evaluated by blood cell counts and biochemical measures. RESULTS: Six of 23 patients in the trientine arm and 1 of 25 patients in the tetrathiomolybdate arm underwent neurologic deterioration (P<.05). Three patients receiving tetrathiomolybdate had adverse effects of anemia and/or leukopenia, and 4 had further transaminase elevations. One patient receiving trientine had an adverse effect of anemia. Four patients receiving trientine died during follow-up, 3 having shown initial neurologic deterioration. Neurologic and speech recovery during a 3-year follow-up period were quite good. CONCLUSION: Tetrathiomolybdate is a better choice than trientine for preserving neurologic function in patients who present with neurologic disease.

Visual contrast sensitivity testing: a comparison of two F.A.C.T. test types.

Measures of visual contrast sensitivity (VCS), rather than traditional measures of visual acuity using high-contrast stimuli, have been presented as better appraisals of visual dysfunction resulting from chemical exposures. The present study sought to determine if differences exist between two available measures of contrast sensitivity that use similar stimuli, specifically, a hand-held chart and an Optec 1000 vision tester. Monocular contrast sensitivity measures using both tests were obtained from 45 individuals as part of a NIOSH neurobehavioral test-battery appraisal. Test-retest reliability was found to be high for both the hand-held system and the Optec 1000 test (r=.750 and.773, respectively). In comparison to the automated test, the hand-held version produced statistically significant higher contrast sensitivity scores for lower spatial frequencies (1.5 and 3.0 cycles per degree) and lower scores for a relatively higher spatial frequency (18.0 cycles per degree [cpd]). Consequently, this study documents a difference in spatial frequency scores obtained with the hand-held form and Optec 1000 form of contrast sensitivity test, and attributes these differences to design characteristics affecting viewing. It is concluded that caution should be taken when making absolute comparisons of contrast sensitivity test scores between neurobehavioral studies that have used different forms of VCS testing.

Treatment of Wilson disease with ammonium tetrathiomolybdate: III. Initial therapy in a total of 55 neurologically affected patients and follow-up with zinc therapy.

BACKGROUND: It is unclear what anticopper drug to use for patients with Wilson disease who present with neurologic manifestations because penicillamine often makes them neurologically worse and zinc is slow acting. OBJECTIVE: To evaluate the frequency of neurologic worsening and drug adverse effects with ammonium tetrathiomolybdate. DESIGN: Open-label study of 55 untreated patients (22 of them new) presenting with neurologic Wilson disease treated with tetrathiomolybdate varying from 120 to 410 mg/d for 8 weeks and then followed up for 3 years. Neurologic function was assessed with scored neurologic and speech tests. SETTING: A university hospital referral setting. PATIENTS: All untreated, newly diagnosed patients with neurologic Wilson disease. INTERVENTION: Treatment with tetrathiomolybdate. MAIN OUTCOME MEASURES: Neurologic function was evaluated by neurologic and speech examinations. Drug adverse effects were evaluated by complete blood cell counts and biochemical measures. RESULTS: Only 2 (4%) of 55 patients treated with tetrathiomolybdate showed neurologic deterioration, compared with an estimated 50% of penicillamine-treated patients. Five of the 22 new patients exhibited bone marrow suppression and 3 had aminotransferase elevations. These numbers are higher than in the original 33 patients and appear to be due primarily to a more rapid dose escalation. CONCLUSIONS: Tetrathiomolybdate shows excellent efficacy in patients with Wilson disease who present with neurologic manifestations. With rapid escalation of dose, adverse effects from bone marrow suppression or aminotransferase elevations can occur.