Playing-related musculoskeletal disorders in musicians: a systematic review of incidence and prevalence

BACKGROUND: Work-related musculoskeletal disorders cause pain, disability and loss of employment for many workers, including musicians. Although performing arts medicine is a growing field, the health problems of musicians remain under-recognized and under-researched. Therefore, the author undertook a systematic review of published information on the incidence and prevalence of playing-related musculoskeletal disorders (PRMDs) in classical musicians. METHODS: Seven databases were searched for the period 1980 to 1996. The main textbook and performing arts medicine journals were searched manually, as were reference lists of all relevant papers. The author also contacted individuals familiar with the literature of performing arts medicine. Studies were included for review if they reported PRMD incidence or prevalence in classical musicians. Of the 24 studies identified, 18 cross-sectional surveys and cohort studies were reviewed. The author subjectively assessed the studies using criteria modified from an existing evaluation scale and used 4 criteria for data combination. On the basis of prevalence values from the eligible studies, chi 2 tests for heterogeneity were performed. RESULTS: Only one study estimated PRMD incidence. Ten of the 17 prevalence studies were ineligible for data combination, because of low response rates and other methodological problems. In the 7 eligible studies, PRMD point prevalence ranged from 39% to 87% in adult musicians and from 34% to 62% in secondary school music students. The best estimates of PRMD prevalence were derived from the 3 studies that excluded mild complaints; these studies indicated that PRMD prevalence was 39% and 47% in adults and 17% in secondary school music students respectively. Statistical combination of data across studies within each demographic category was not possible. INTERPRETATION: Available data indicate that the prevalence of PRMD in adult classical musicians is comparable to the prevalence of work-related musculoskeletal disorders reported for other occupational groups. Several recommendations for future research are outlined.     

Mental disorders and access to medical care in the United States

OBJECTIVE: The authors examined the barriers to receipt of medical services among people reporting mental disorders in a representative sample of U.S. adults. METHOD: The sample was drawn from adults who responded to the 1994 National Health Interview Survey (N=77,183). The authors studied the association between report of a mental disorder and 1) access to health insurance and a primary provider, and 2) actual receipt of medical care. Multivariate techniques were used to model problems with access as a function of mental disorders, controlling for demographic, insurance, and health variables. RESULTS: While people who reported mental disorders showed no difference from those without mental disorders in likelihood of being uninsured or of having a primary care provider, they were twice as likely to report having been denied insurance because of a preexisting condition or having stayed in their job for fear of losing their health benefits. Among respondents with insurance, those who reported mental illness were no less likely to have a primary care provider but were about two times more likely to report having delayed seeking needed medical care because of cost or having been unable to obtain needed medical care. CONCLUSIONS: People who reported mental disorders experienced significant barriers to receipt of medical care. Efforts to measure and improve access to health care for this population may need to go beyond simply providing insurance benefits or access to general medical providers.     

The prevalence of cervical cancer screening iin the United States in 1970

Peripheral receptors signalling in both the 3 main divisions of the trigeminal nerves and in the glossopharyngeal nerves are most likely involved in the onset of the apnea in diving ducks. Since the response also takes place when ducks are submerged in mercury, these peripheral receptors are hardly specific to water. Neither any of the 3 main groups of trigeminal, nor the glossopharyngeal receptors are alone responsible for the initiation of the apnea. Most likely the apnea takes place when the total impact on the 'respiratory centre' in the brain exceeds a certain treshold value, due to activation of a certain number of both trigeminal and glossopharyngeal peripheral receptors. However, even very local stimulation of the glottal area invariably evoked apnea, indicating a higher density of receptors there than for example on the beak or in the nares. This idea is supported by the fact that not even heavy rain evokes any response at all. It is unlikely that the cardiovascular adjustments displayed by diving ducks are directly coupled to the apnea response (i.e. to stimulation of peripheral receptors). Rather they are supposed to be components in orienting and chemoreceptor reflexes.     

Occupational injury and illness in the United States. Estimates of costs, morbidity, and mortality

OBJECTIVE: To estimate the annual incidence, the mortality and the direct and indirect costs associated with occupational injuries and illnesses in the United States in 1992. DESIGN: Aggregation and analysis of national and large regional data sets collected by the Bureau of Labor Statistics, the National Council on Compensation Insurance, the National Center for Health Statistics, the Health Care Financing Administration, and other governmental bureaus and private firms. METHODS: To assess incidence of and mortality from occupational injuries and illnesses, we reviewed data from national surveys and applied an attributable risk proportion method. To assess costs, we used the human capital method that decomposes costs into direct categories such as medical and insurance administration expenses as well as indirect categories such as lost earnings, lost home production, and lost fringe benefits. Some cost estimates were drawn from the literature while others were generated within this study. Total costs were calculated by multiplying average costs by the number of injuries and illnesses in each diagnostic category. RESULTS: Approximately 6500 job-related deaths from injury, 13.2 million nonfatal injuries, 60,300 deaths from disease, and 862,200 illnesses are estimated to occur annually in the civilian American workforce. The total direct ($65 billion) plus indirect ($106 billion) costs were estimated to be $171 billion. Injuries cost $145 billion and illnesses $26 billion. These estimates are likely to be low, because they ignore costs associated with pain and suffering as well as those of within-home care provided by family members, and because the numbers of occupational injuries and illnesses are likely to be undercounted. CONCLUSIONS: The costs of occupational injuries and illnesses are high, in sharp contrast to the limited public attention and societal resources devoted to their prevention and amelioration. Occupational injuries and illnesses are an insufficiently appreciated contributor to the total burden of health care costs in the United States.     

Age of initiating selected health-risk behaviors among high school students in the United States

The XYL1 and XYL2 genes from Pichia stipitis encoding xylose reductase (XR) and xylilitol dehydrogenase (XDH), respectively, were transformed into Saccharomyces cerevisiae. These two genes were placed in different directions under the control of the alcohol dehydrogenase I (ADHI) and phosphoglycerate kinase (PGK) promoters and inserted into the E. coli-yeast shuttle plasmid YEp24. Different recombinant S. cerevisiae strains were constructed with different specific activities of XR and XDH. The highest XR or XDH activities were obtained when the expressed gene was controlled by the PGK promoter and located downstream after the ADHI promoter-gene-terminator sequence. The XR/XDH ratio (ratio of specific enzyme activities of XR and XDH) in these recombinant S. cerevisiae strains varied from 17.5 to 0.06. In order to enhance xylose utilization, in the XYL1, XYL2 containing S. cerevisiae strains, the native TKL1 gene encoding transketolase and the TALI gene encoding transaldolase were also overexpressed, which showed considerably good growth on the xylose plate. Fermentation of the recombinant S. cerevisiae strains containing XYL1, XYL2, TKL1, and TAL1 were studied with mixtures of glucose and xylose. The strain with XR/XDH ratio of 0.06 consumed 3.25 g/L xylose and formed no xylitol and less glycerol and acetic acid, but more ethanol compared with the strains with a higher XR/XDH ratio.     

Cumulative trauma disorders among apparel manufacturing employees in the southeastern United States

Factors associated with cumulative trauma disorders (CTDs) of the upper extremities were studied retrospectively, using data from three apparel manufacturing plants in the southeastern United States. Reported CTDs among the employees at risk during fiscal years 1991 and 1992 were analyzed focusing on individual and plant variables. Results showed that CTD rates increased from 1991 to 1992 and fluctuated in a cyclical pattern each year, peaking during January, March, and August. Employee age and duration of employment were associated with CTD rates. Employees aged 45 to 49 had higher CTD rates than those in any other age groups. Employees with 1 to 3 years' experience had higher CTD rates than employees with more years of service.     

Estimates of fatal child abuse and neglect, United States, 1979 through 1988

The results of recent surveys in the United States have suggested a rising tide of fatalities due to child abuse or neglect (CAN). Because these surveys lack consistency in case definition and are incomplete in coverage, the use of death certificate data to estimate the number of CAN deaths was explored. To estimate these deaths among children 0 through 17 years old for 1979 through 1988, three models were formulated, each comprising six coding categories: (1) deaths coded explicitly as due to CAN, (2) homicides, (3) injury deaths of undetermined intentionality, (4) accidental injury deaths, (5) sudden infant death syndrome fatalities, and (6) natural-cause deaths. Research studies and crime data were relied on to estimate the proportions of deaths in categories 2 through 6 that were actually due to CAN, and other assumptions were varied to create a range of estimates. For the 10-year period, the estimated mean annual CAN fatalities ranged from 861 to 1814 for ages 0 through 4, and from 949 to 2022 for ages 0 through 17. Child abuse and neglect death rates did not increase over the period; in fact, they were relatively stable for ages 0 through 17 and showed a modest decline for 0 through 4. Ninety percent of fatal CAN occurs among children younger than 5 years old, and 41% occurs among infants. About 85% of CAN deaths are recorded as due to other causes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Health economics and cost implications of anxiety and other mental disorders in the United States

BACKGROUND: Mental disorders impose a multi-billion dollar burden on the economy each year; translating the burden into economic terms is important to facilitate formulating policies about the use of resources. METHODS: For direct costs, data were obtained from national household interview and provider surveys; for morbidity costs, a timing model was used that measures the lifetime effect on current income of individuals with mental disorders, taking into account the timing of onset and the duration of these disorders, based on regression analysis of Epidemiologic Catchment Area study data. RESULTS: The total economic costs of mental disorders amounted to US$147.8 billion in 1990. Anxiety disorders are the most costly, amounting to $46.6 billion, or 31.5% of the total; schizophrenic disorders accounted for $32.5 billion, affective disorders for $30.4 billion, and other mental disorders for $38.4 billion. CONCLUSIONS: Mental illnesses, especially anxiety disorders, are costly to society. Although anxiety disorders have a higher prevalence than affective disorders and schizophrenia, use of medical care services is lowest for anxiety disorders. Anxiety disorders appear to be under-recognised and untreated even though treatment interventions have been shown to be effective and can be delivered in a cost-efficient manner.     

Negligible prevalence of antibodies against Trypanosoma cruzi among blood donors in the southeastern United States

The ultrastructure of alpha-bacteroids in relation to the fat-body cells of the lantern bug Pyrops candelaria was described. The fat-body-cell cytoplasm contained numerous mitochondria, rough endoplasmic reticula, vacuoles, and storage granules. Its nucleus had scattered chromatin materials. The alpha-bacteroid was enveloped by three membrane layers, namely, the plasma membrane, the cell wall, and the membrane envelope. Its cytoplasm contained amorphous dense bodies. The bacteroid reproduced by binary fission. Tracheoles were also found among fat-body cells.     

Extended field-of-view sonography in musculoskeletal disorders

The endogenous dipeptide, alpha-N-acetylaspartylglutamate behaves as a partial agonist of N-methyl-D-aspartate receptors, but can also activate metabotropic glutamate receptors, with a high degree of selectivity for the metabotropic glutamate receptor 3 subtype. Knowing that agonists of group-II metabotropic glutamate receptors (i.e. of mGlu2 and -3 receptors) are neuroprotective, we have examined the neuroprotective activity of alpha-N-acetylaspartylglutamate in mixed cultures of mouse cortical cells exposed to a toxic pulse with N-methyl-D-aspartate. Alpha-N-acetylaspartylglutamate co-applied with N-methyl-D-aspartate was neuroprotective, but its action was insensitive to the selective group-II metabotropic glutamate receptor antagonist, ethylglutamate. Protection was instead antagonized by ethylglutamate when alpha-N-acetylaspartylglutamate was applied to the cultures immediately after the N-methyl-D-aspartate pulse, a condition in which there was no direct competition between alpha-N-acetylaspartylglutamate and N-methyl-D-aspartate at the level of N-methyl-D-aspartate receptors. alpha-N-acetylaspartylglutamate was highly neuroprotective when transiently applied to pure cultures of cortical astrocytes and the conditioned medium, collected 20 h later, was transferred to sister mixed cultures challenged with N-methyl-D-aspartate. This particular form of neuroprotection was attenuated or abolished when astrocytes where exposed to alpha-N-acetylaspartylglutamate in the presence of the group-II metabotropic glutamate receptor antagonists ethylglutamate or (2S, 1'S,2'S,3'R)-2-(2'-carboxy-3'-phenylcyclopropyl)glycine, but not in the presence of the N-methyl-D-aspartate receptor antagonist, D-2-amino-5-phosphonopentanoate. These results indicate that alpha-N-acetylaspartylglutamate induces neuroprotective effects in culture, which are mediated, at least in part, by the activation of glial metabotropic glutamate receptor 3 receptors.     

Aiding troubled employees: the prevalence, cost, and characteristics of employee assistance programs in the United States

Bilirubin neurotoxicity can be mediated by numerous mechanisms due to its increased permeability in neuronal membranes. The present study tests the hypothesis that a prolonged bilirubin infusion modifies the N-methyl-D-aspartate (NMDA) receptor/ ion channel complex in the cerebral cortex of newborn piglets. Studies were performed in seven control and six bilirubin-exposed piglets, 2-4 d of age. Piglets in the bilirubin group received a 35 mg/kg bolus of bilirubin followed by a 4-h infusion (25 mg/kg/h) of a buffer solution containing 0.1 N NaOH, 5% human albumin, and 0.055 Na2HPO4 with 3 mg/mL bilirubin. The final mean bilirubin concentration in the bilirubin group was 495.9 +/- 85.5 mumol/L (29.0 +/- 5.0 mg/dL). The control group received a bilirubin-free buffer solution. Sulfisoxazole was administered to animals in both groups. P2 membrane fractions were prepared from the cerebral cortex. [3H]MK-801 binding assays were performed to study NMDA receptor modification. The Bmax in the control and bilirubin groups were 1.20 +/- 0.10 (mean +/- SD) and 1.32 +/- 0.14 pmol/mg protein, respectively. The value for Kd in the control brains was 6.97 +/- 0.80 nM compared with 4.80 +/- 0.28 nM in the bilirubin-exposed brains (p < 0.001). [3H]Glutamate binding studies did not show a significant difference in the Bmax and Kd for the NMDA-specific glutamate site in the two groups. The results show that in vivo exposure to bilirubin increases the affinity of the receptor (decreased Kd) for [3H]MK-801, indicating that bilirubin modifies the function of the NMDA receptor/ion channel complex in the brain of the newborn piglet. We speculate that the affinity of bilirubin for neuronal membranes leads to bilirubin-mediated neurotoxicity, resulting in either short- or long-term disruption of neuronal function.     

The economic cost of musculoskeletal disorders in Canada

OBJECTIVE: This study estimated the total cost of musculoskeletal disorders for Canadians in 1994 and assessed the sensitivity of these cost estimates to variations in the definition of musculoskeletal disorders. METHODS: Disease-related costs, from a societal perspective, were measured using a prevalence-based analysis. First, direct treatment costs, including expenditures on hospitals and other institutions, physicians and other health professionals, drugs, research, and other items were assessed. Second, indirect costs associated with lost (or foregone) productivity due to disability and premature mortality were evaluated using the human capital approach. RESULTS: The total cost of musculoskeletal disorders in Canada was $25.6 billion (in 1994 Canadian dollars, $1.00 CDN approximately $0.75 US) or 3.4% of the gross domestic product. Direct and indirect costs were estimated at $7.5 billion and $18.1 billion, respectively. Lower and upper bound estimates of the total cost of musculoskeletal disorders, derived from the sensitivity analysis, were $19.9 billion and $30.8 billion, respectively. Wide variations were reported in the total cost of various musculoskeletal disorder subcategories, with the highest costs reported for injuries ($10.7 billion), back and spine disorders ($8.1 billion), and arthritis and rheumatism ($5.9 billion). CONCLUSIONS: The economic cost of musculoskeletal disorders was substantial and was sensitive to the definition of musculoskeletal disorders and other underlying assumptions. The hallmark of this study was the variation between subcategories in their cost, pattern of health resource use, and sequelae. The cost estimates may provide guidance in setting priorities for research and prevention activities.     

Physical activity and women in the United States: an overview of health benefits, prevalence, and intervention opportunities

Despite decades of physical activity research and interventions conducted on men, very little is known about the patterns of physical activity among US women. Rates from several national surveys show much lower rates of physical activity for women than for men. Among women, rates may vary by socioeconomic status. Studies relating physical activity and experience with heart disease, cancer, osteoporosis, and mental health are discussed. Interventions in the workplace and the community may increase the level of physical activity among US women. A history of not participating in exercise and lack of time for this activity appear to be important constraints for many women. The Surgeon General's Report on physical activity sanctioned future research on specific groups, such as women. Applied research coupled with community and workplace policies that support women's efforts to be more physically active may decrease the rates of some chronic diseases in this population.