Social disparities in musculoskeletal disorders and associated mental malaise: findings from a population-based survey in France.

AIMS: Various types of musculoskeletal disorders (MSDs) have comorbid mental disorders, which may in turn have a negative influence on disease course and role impairment, but the contribution of social factors to this type of comorbidity is a much under-researched area. This study investigates whether there is a socially patterned association of MSDs with different dimensions of mental malaise. METHODS: The sample included 3,368 economically active participants aged 18-64 years, randomly selected from the Lorraine region in north-eastern France. Information was provided through a post-mailed questionnaire on fatigue, sadness/depression (Duke questionnaire) and cognitive disability during the last eight days. RESULTS: MSDs were significantly more prevalent in manual workers, clerks and other occupations than in upper and intermediate professionals, and similar occupational disparities were found for cognitive disability, fatigue and sadness/ depression. Stratifying the sample, we found the occupational disparities in cognitive disability to be much stronger among participants suffering from MSDs than among participants not suffering from MSDs, and the occupational disparities in fatigue and sadness/depression to be limited to the subsample of subjects suffering from MSDs. CONCLUSIONS: The findings demonstrate that the association of MSDs with mental malaise is much stronger in the lower occupational groups than in the higher groups. Given that psychological factors are implicated in disease prognosis and in the development of disabilities, awareness of the social dimension of the association and treatment of the comorbid mental disorders could open a promising avenue for reducing social inequalities in disability related to MSDs.

[Prevalence of impairments and social inequalities]. / Prévalence des déficiences et disparités sociales.

BACKGROUND: Population ageing and longer duration of the working career could increase the prevalence of impairments and disabilities whereas there have been few data to help prevention and care. This study aimed at describing the prevalence of various types of impairments and assessing their social inequalities in the Lorraine population (north-eastern France). METHODS: The sample included 6.214 subjects aged 15 or more from 8.000 households randomly selected in the Lorraine population. A mailed questionnaire including socio-demographical characteristics, job, and various types of impairments was used. The data were analysed with the chi2 independence test, the adjusted odds ratio (OR) and the Mantel-Haenszel test. RESULTS: The prevalence of at least one impairment was 30% in both sexes. It varied from about 20% for subjects aged less than 40 years to about 60% for the subjects aged 70 years or more. It was higher in men than in women among the individuals aged more than 50 years (OR adjusted on age: 1.22, 95% CI: 1.04-1.44). The impairments were generally multiple for the subjects aged over 50. The prevalence of at least one impairment was higher for workmen (OR adjusted on age: 2.11, 95% CI: 1.68-2.66), farmers, craftsmen, traders and heads of firms (OR adjusted on age: 1.60, 95% CI: 1.17-2.18) and for employees (OR adjusted on age: 1.62, 95% CI: 1.29-2.03) in comparison with executives, intellectual professionals and teachers. For workmen a higher prevalence was observed for all types of impairments: intellectual and psychological functions, language, hearing, vision, visceral functions, and skeleton and posture. Farmers, craftsmen, traders, heads of firms and employees showed an excess for most types of impairments. Social inequalities were significant for various age groups during their period of occupational activity, but not after retirement. Unemployed people also had an excess of impairments. CONCLUSION: The prevalence of impairments strongly increased with advancing age. Marked inequalities were observed between various socio-occupational categories. Men were more affected than the women over 50 years of age. Impairments represent a health index which is useful for prevention to reduce their causes and consequences.

[School-related injuries: incidence, causes, and consequences]. / Les accidents scolaires dans des établissements d'enseignement général: incidence, causes, et conséquences.

BACKGROUND: School accidents are frequent but little epidemiological information is available to guide prevention. In this study we examined the incidence, causes, and consequences of school accidents as a function of the pupil's characteristics. METHODS: An epidemiological study was conducted in all 2 396 adolescents attending two secondary school groups. Sociodemographic characteristics of the pupils and data on school accidents during a one-year period were collected using a questionnaire filled out by the school nurse in the presence of the victims. The chi-square independence test, Fisher's exact test and the logistic regression method were used for the statistical analysis. RESULTS: Sports and physical training (SPT) accidents accounted for 52.8% of the accidents, recreation accidents for 12.7% and other accidents for 33.6%. The annual incidence of one accident or more, for all types of accidents combined, was 12.9%, that for two or more accidents 2.3%. The rate of SPT and recreation accidents decreased strongly with age. SPT accidents were more frequent in girls, the other accidents more frequent in boys. Among the SPT accidents, 69.2% occurred under training conditions and 33.7% were caused by another person. Causes mentioned by the victims were: carelessness (26.0%), clumsiness (17.5%), misappreciation of risk (13.8%), tiredness (9.5%), nervous irritation (8.6%), rowdyism (6.0%), disrespect of the teacher's instructions (6.0%). The lesions were: contusions (50.7%), wounds (18.7%), tendinitis (11.7%), wrenches (9.2%), others (7.3%). They differed between age groups, sex, and category of sports. Localizations were mainly: fingers (27.4%), other localizations of the upper limb (20.1%), head (20.6%). A physician was consulted for 19.5% of the accidents and hospitalization followed 2.7%. Absence from school and exemption from SPT were frequent (11.4% and 16.3% respectively). CONCLUSION: The results could be used to inform adolescents so they and their families could become more aware of the risk of school accidents. Prevention should mainly focus on the younger children. An effort must be made regarding risk assessment in order to help the pupils become more careful and responsible during their sports activities. The choice of these activities and the materials used should be made more suitable for adolescents.

Comment on "Finding finite-time invariant manifolds in two-dimensional velocity fields" [Chaos 10, 99 (2000)].

This note serves as a commentary of the paper of Haller [Chaos 10, 99 (2000)] on techniques for detecting invariant manifolds. Here we show that the criterion of Haller can be improved in two ways. First, by using the strain basis reference frame, a more efficient version of theorem 1 of Haller (2000) allows to better detect the manifolds. Second, we emphasize the need to nondimensionalize the estimate of hyperbolic persistence. These statements are illustrated by the example of the Kida ellipse. (c) 2001 American Institute of Physics.

Associations of family environment and individual factors with tobacco, alcohol, and illicit drug use in adolescents.

Despite abundant literature the respective roles of psychosomatic status, personality, health perception, family environment, and sport activity in tobacco, alcohol and illicit drug use have not been well known. To assess their roles, an epidemiological cross-sectional study was conducted in 3294 middle and high school adolescents, 2396 (73%) of whom agreed to participate. The standardized questionnaire was filled out by the teenagers under the supervision of the teachers. Strong associations were found between tobacco, alcohol, and illicit drug use. The prevalence of alcohol use and illicit drug use were respectively 7 and 10 times higher in smokers than in non-smokers. On the whole, the potential risk factors for tobacco, alcohol, and illicit drug use were age, psychosomatic status and psychotropic drug consumption, boring family atmosphere, not living with both father and mother, and health perception. Mother being a housewife was a protective factor. No marked role was noted for the head of family's socio-occupational category. Personality would be indicators of self-control ability. Indeed, some self-reported personalities (serious, attentive, calm, organized) had protection roles whereas some others (easily irritable, aggressive, worried, clumsy, careless, solitary, etc.) were risk factors (risk-taking or deviant behaviors). Some sports activities were found to be negatively related, but some others related positively with drug use, possibly due to repetitive meetings between the adolescents at risk. Preventive measures may be targeted at these risk factors.

[A software for comparing ambulatory blood pressure measurements (ABPM)]. / Un logiciel pour l'étude comparative des mesures ambulatoires de pression artérielle.

The software (MAPA-PC) for personal computers, designed by the author, provides precise and fast studies of ABPM, especially when comparing two anti-hypertensive treatments. It implies strict definitions of groups (e.g. dippers), indices (peak, trough, peak/trough ratio), and the type of smoothing of measured values: means (over 1, 2 or 3 hours) or smoothing by functions (polynomials or trigonometric series). The software calculates standard parameters (nighttime and daytime means, peak, trough...) as well as more original values (nighttime and period from points of inflexion in the curve, slope in these points, coefficients of variation on differences between 2 ABPM of a given subject...). It uses statistical tests (Mann and Whitney's U. Pearson's chi square, Snedecor's F) to compare results of treatment. It provides many types of curves (blood pressure lines, box-plots) which show kinetics and variability of blood pressure. The user can compare various types of smoothing (e.g. 2 vs 3 harmonics in Fourier series). The software was used on 237 records of 79 patients, in a randomized trial. It was written with Turbo Pascal and works on DOS personal computers. It is interesting for epidemiologic studies or clinical trials in which ABPM are used.

[Evaluation of the mortality related to nosocomial infections. An approach by a homogeneous group of patients, from bacteriology and data of hospitalization (1989-1993)]. / Evaluation de la sur-mortalité liée aux infections nosocomiales. Une approche par groupe homogène de malades, à partir de la bactériologie et des résumés d'hospitalisation (1989-1993).

We cross matched the informations from the medical records of the PMSI (French Program of Medicalisation of the Information System) with those from the bacteriology data base. The hospitalisation summaries provide the length of hospital stay, the mortality and the pathology defined by DRG (Diagnosis Related Group). Bacteriological data allow the diagnosis of nosocomial infections (NI) when using an appropriate methodology ("doubles" and early samples are not taken in account). Then it is possible to estimate the mortality when there are NI and No. 4499 stays NI were compared with 140,463 stays without NI. Mortality is 14.4% in NI group (17.5% in medecine and 8.6% in surgery) against 2.1% in the group without NI (2.5% in medecine and 0.8% in surgery). Among the 58 DRG's studied (more than 19 cases with NI), mortality and relative risk varie a lot. Results are estimations because they are many bias.

Fortuitous diagnosis of the association of hemoglobin J-Broussais with beta + thalassemia.

The authors report a case, not described so far in literature, of an association of HbJ-Broussais [alpha (90 (PG2) lys-->asn beta 2] with beta + thalassemia in a young girl born of Italian father and Breton mother. This association is clinically silent. Biochemistry revealed, besides HbA, the presence of HbJ-Broussais in the proportion of 19.4% and HbA2 value of 3.9%. These percentages, slightly lower than expected, are explained. A familial study is presented.

Serum lipid, apolipoprotein and lipoparticle levels in the human fetus.

Blood collected from 62 fetuses aged 20-38 weeks of gestation was studied. The values of ten lipid parameters were determined: cholesterol (TC), triglycerides (TGs), apolipoprotein A1 (apo A1), apolipoprotein B (apo B), apolipoprotein E (apo E), total apolipoprotein CIII (apo CIII), apolipoprotein CIII present in particles containing apo B (apo CIII LpB) or not (apo CIII Lp non-B), lipoparticles A1 (LpA1), and lipoprotein a (Lp(a)). The results show that, except for apo E, all the studied parameters were present in lower concentrations than in adults and newborns, and that Lp(a) is not detectable at that stage in life.

Increase in thiobarbituric acid-reactive substances and vascular complications in type 2 diabetes mellitus.

Lipid peroxidation was assessed by measuring the concentrations of thiobarbituric acid-reactive substances in plasma from 204 Type 2 diabetic patients, relative to 107 controls. The concentrations obtained in diabetic patients (3.08 +/- 0.37 mumol/l) were significantly higher than in controls (2.80 +/- 0.34 mumol/l) (p < 0.0001). Values were also significantly increased in patients with macroangiopathy and/or microangiopathy (3.17 +/- 0.41 mumol/l), relative to patients void of vascular complications (2.92 +/- 0.34 mumol/l) (p < 0.001). Elevated concentrations were independent of the type of vascular complication and their possible associations. In patients without vascular affection, thiobarbituric acid-reactive substances were in significantly higher concentrations in hypertensive (3.07 +/- 0.36 mumol/l) than in normotensive (2.87 +/- 0.29 mumol/l) (p < 0.01) patients. There was a correlation between these values and those of total cholesterol (r = 0.46, p < 0.0001) and triglyceride (r = 0.45, p < 0.0001). Statistical analysis by multivariate logistical regression revealed that among the independent factors (TBARS, APO A1, hypertension, age), thiobarbituric acid-reactive substances constituted the parameter most strongly linked to the existence of vascular complications. This study has evidenced a lipid peroxidation disorder in non insulin- dependent diabetes mellitus, more marked in patients with vascular affection. Thiobarbituric acid-reactive substances appear to be an independent marker of vascular complications in Type 2 diabetes.

[Susceptibility of LDL to lipid peroxidation in non-insulin-dependent diabetes mellitus with or without macroangiopathy]. / Susceptibilité des LDL à la peroxydation lipidique dans le diabète non insulino-dépendant avec ou sans macroangiopathie.

Since oxidized LDL may play a role in the genesis of atheroma, which is the primary complication of non-insulin-dependent diabetes mellitus (NIDDM), we investigated whether the LDL of diabetic patients were more prone to oxidation than those of healthy controls. We therefore studied the susceptibility of LDL to oxidation by phenylhydrazine (LDL-PO) in NIDDM patients with or without macroangiopathy, and in controls. Results showed that the LDL of patients with macroangiopathy (n = 50) were more susceptible to oxidation than those of both NIDDM patients without vascular complications (n = 50) and controls (n = 50). In diabetic patients, there was a positive correlation between LDL-PO and the following parameters: total cholesterol, triglycerides, LDL cholesterol, apolipoprotein B. In contrast, there was no correlation between LDL-PO and the parameters of glycemic control (fasting glucose, HbAlc). After analyzing the composition of LDL, it appeared that LDL-PO values in diabetic patients were positively correlated with those of all LDL constituents. The increase in LDL-PO observed in the group of NIDDM patients with macroangiopathy could be a consequence of an increase in the LDL triglyceride content in these patients.

[Estimation with bacteriology of the evolution of nosocomial infections between 1989 and 1991 in an university hospital]. / Estimation à partir de la bactériologie de l'évolution des infections nosocomiales entre 1989 et 1991 dans un hôpital universitaire.

The bacteriological laboratory data base was studied with an original software (Bacterio) and an appropriate method ("doubles" and early samples are not taken in account) to estimate the nosocomial infections. The incidence rates for 100 hospitalizations at the University hospital of Nancy are 9.2, 8.2 et 8.2 for respectively 1989, 90 et 91. These values are corrected while taking into account a method's sensibility of 65%. The 1000 days of hospitalization's rates allow a better comparison between the medical departments. For the whole hospital, the results are respectively of 7.9, 7.2 and 7.5%. Even if the many bias described cannot always been checked, the method gives some evolutivity indicators which are very useful for the hygienists.

LDL sialic acid content in patients with coronary artery disease.

Low density lipoproteins (LDL) are considered to be the most atherogenic of lipoproteins. These LDL can be modified and oxidative modifications are now well known. In addition, other atherogenic modifications of LDL exist, such as desialylation. In the present study sialic acid content was determined in LDL preparations obtained from patients with coronary artery disease (CAD+) and compared with that of healthy subjects and patients without coronary heart disease (CAD-). The sialic acid concentration was found to be statistically lower (P < 0.05) in the LDL of CAD+ patients (11.6 +/- 2.7 micrograms/mg of protein) than in the LDL of controls (16.5 +/- 5.6 micrograms/mg of protein) or in the LDL of CAD- patients (15.3 +/- 3.8 micrograms/mg of protein). In subgroups of CAD+ patients divided according to the severity of the disease, no statistically significant difference was observed in LDL sialic acid content. This work confirms the presence of desialylated LDL in the sera of patients with atheroma.

Plasma malondialdehyde in type 1 and type 2 diabetic patients.

Malondialdehyde, a marker of lipid peroxidation, was measured as thiobarbituric acid reactive substances (TBARS) in 117 diabetic patients and 53 controls. Patients were divided into groups and subgroups according to the type of diabetes (type 1 and type 2) and the existence or not of vascular complication (macro- or micro-angiopathy). Results showed that TBARS concentrations were significantly higher in type 1 (P < 0.0001) and type 2 (P < 0.001) diabetic patients than in the control group. The plasma TBARS concentrations in type 1 and type 2 diabetic patients did not differ significantly. Among the patients with vascular disease, type 2 diabetic patients with macroangiopathy had significantly higher TBARS concentrations than patients with no vascular complication (P < 0.05). Whichever the type of diabetes, there was no correlation between TBARS concentrations and glycaemic control: glycosylated haemoglobin, fasting blood glucose. This study confirmed the existence of lipid peroxidation disorders in diabetic patients.