PubMed HealthSearch

Biomedical subjects

M Gagnon

Publications and source records attributed to M Gagnon.

At least 19 recordsLinked to original sources

Principal lifetime occupation and cognitive impairment in a French elderly cohort (Paquid).

The purpose of the present study was to examine the relation between principal lifetime occupation and cognitive performance with the initial data collected (1988-1989) in a cohort of 3,777 community residents of the area of Bordeaux, France, aged 65 years and older. Subjects were considered as cognitively impaired if they scored under 24 on the French version of the mini-mental state examination. Cognitive impairment was found to vary significantly across the different occupational categories. Results of the logistic regression show that age, sex, and educational level are significantly related to cognitive impairment. Moreover, after controlling for these and other covariates, farmworkers (odds ratio (OR) = 6.1, 95% confidence interval (CI) 3.3-11.4), farm managers (OR = 2.9, 95% CI 1.6-5.1), domestic service employees (OR = 2.8, 95% CI 1.5-5.1), and blue-collar workers (OR = 2.5, 95% CI 1.4-4.4) had a higher risk of cognitive impairment than did subjects who had an intellectual occupation. Follow-up of the cohort will permit precise determination of the role of principal lifetime occupation in subsequent cognitive deterioration. Occupational status should be taken into consideration when studying brain aging.

Age Factors

The influence of dynamic factors on triaxial net muscular moments at the L5/S1 joint during asymmetrical lifting and lowering.

Asymmetrical lifting and lowering are predominant activities in the workplace. Mechanical causes are suggested for many back injuries and the dynamic conditions within which spine loading occurs are related to spine loading increase. More data on tridimensional biomechanical lumbar spine loading during asymmetrical lifting and lowering are needed. A tridimensional dynamic multisegment model was developed to compute spinal loading for asymmetrical box-handling situations. The tridimensional positions of the anatomical markers were generated by a direct linear transformation algorithm adapted for the processing of data from two real and two virtual views (mirrors). Two force platforms measured the external forces. Five male subjects performed three variations (slow, fast and accelerated) of asymmetric lifting and two variations (slow and fast) of asymmetric lowering. The torsional, extension/flexion and lateral bending net muscular moments at the L5/S1 joint were computed and peak values selected for statistical analysis. For the lifting task, the fast and accelerated conditions showed significant increases over the slow condition for torsion, extension/flexion and lateral-bending moments. The accelerated condition also showed significant increases over the fast condition for extension. A comparison between lifting and lowering tasks showed equivalent loadings for torsion and extension. The moments were compared to average maximal values measured on equivalent male subject populations by isokinetic dynamometry. This showed torsional and extension values of 30 and 83% of the maximal possible subject capacity, respectively. These results demonstrated that dynamic factors do influence the load on the spine and highlighted the influence of both lifting and lowering on the loading of the spine. This suggested that for a more complete analysis of asymmetrical handling, the maximal velocity and acceleration produced during lifting should be included.

Adult

Depressive symptomatology and cognitive functioning: an epidemiological survey in an elderly community sample in France.

As part of a 5-year, prospective, epidemiological survey of normal and pathological ageing, this cross-sectional analysis examines the relationship between depressive symptomatology (CES-D) and cognitive functioning (MMS) in a community sample of 2792 non-institutionalized persons (age greater than or equal to 65) living in Southwest France. Of the sample, 13.4%, report depressive symptoms above the cut-off. A significant association was found between CES-D and MMS scores, but after adjusting for age, living arrangements, and especially functional limitations, the relationship remained strong only for women.

Activities of Daily Living

Biomechanical exploration on dynamic modes of lifting.

Whatever the lifting method used, dynamic factors appear to have an effect on the safe realization of movement, and NIOSH guidelines recommend smooth lifting with no sudden acceleration effects. On the other hand, inertial forces may play an important role in the process of transfer of momentum to the load. The direction by which these inertial forces may affect the loadings on body structures and processes of energy transfers cannot be determined a priori. A biomechanical experiment was performed to examine if there were differences in the execution processes between a slow-continuous lift and an accelerated-continuous lift, and also between accelerated lifts either executed continuously or interrupted with a pause. The lifts were executed from a height of 15 cm to a height of 185 cm above the head and with two different loads (6.4 and 11.6 kg). Five experienced workers in manual materials handling were used as subjects. Films and force platforms recordings supplied the data; dynamic segmental analyses were performed to calculate net muscular moments at each joint; a planar single-muscle equivalent was used to estimate compression loadings at L5/S1; total mechanical work, joint work distribution, and energy transfers were determined from a kinetic approach based on the integration of joint power as a function of time. Analyses of variance with repeated measures were applied to the three treatments. The results showed that joint muscular moments, spinal loadings, mechanical work, and muscular utilization ratios were generally increased by the presence of acceleration without inducing benefits of improved energy transfers; therefore slower lifts with reduced acceleration may be safer when handling moderately heavy loads. The maximum values of kinematic and kinetic factors were generally not affected by the pause, but the occurrence of jerks in the movement (acceleration, ground forces, and muscular moments) suggests that the pause may not be indicated when considering total exposure to muscular exertion. Full consideration should be given to the dynamics of motion when assessing risk factors in working tasks.

Acceleration

Health measures correlates in a French elderly community population: the PAQUID study.

PAQUID is an epidemiologic prospective study of mental and functional aging. A sample of 4,050 community-dwelling individuals, aged 65 and over, was randomly selected from electoral lists of 37 parishes of Gironde after stratification by age, sex, and size of urban unit; 68.9 percent agreed to participate. Baseline information was obtained from a one-hour home interview. Health measures included ADL, IADL, mobility, Rosow scale, and two subjective health assessments. Depressive symptomatology was assessed by the CES-D scale and cognitive functioning by Folstein's MMS. Dependence rates vary from 9.7 percent to 71.9 percent according to the indicator under consideration. Cross-sectional correlations with dependence are significant for age, sex, education, rural setting, joint pain, dyspnea, hearing and visual impairment, MMS score, and depression. In logistic regressions, only dyspnea, MMS score, and depression are always significantly correlated with dependence, whichever the indicator.

Activities of Daily Living

Improving screening for dementia in the elderly using, Mini-Mental State Examination subscores, Benton's Visual Retention Test, and Isaacs' Set Test.

The Mini-Mental State Examination score is often used as a screening test for dementia. We studied its properties for a population of French community residents, using a sample of 2,792 randomly selected subjects in Gironde, France. When the traditional cutoff point 23-24 was used, we observed a sensitivity of 1.0 and a specificity of 0.77. We sought to increase the specificity of the test, while keeping sensitivity at 1.0, with the use of logistic regression analysis. We found (1) a specificity of 0.81 when "recall three objects" and "orientation to time" were added to the Mini-Mental State Examination score; (2) a specificity of 0.90 when Benton's Visual Retention Tests and Isaacs' Set Test of Verbal Fluency were added to the Mini-Mental State Examination score and subscores; and (3) no improvement in specificity when age and educational level were included in the analyses.

Age Factors

Statistical description of the Mini-Mental State Examination for French elderly community residents. Paquid Study Group.

The distribution of total Mini-Mental State Examination (MMSE) scores, individual items, and groups of items were studied in French elderly community residents from a random sample of 2727 subjects. Serial seven, recall three objects, and copy pentagons had the lowest percentage of correct responses, while orientation to place, naming two objects, and three objects registration had the highest percentage of correct responses. The structure of correlation of the items was studied using Principal Components Analysis. The projection of the items on the first axis reflects the tendency of the items to vary in the same direction and is compatible with the fact that the MMSE items are all indicators of the same concept: cognitive performance. The second and third axes identify clusters of highly correlated variables and provide support for the internal validity of the MMSE score for a French population. The full MMSE score seems to be a valid instrument for the evaluation of cognitive performance in community-based elderly residents.

Aged

Instrumental activities of daily living as a screening tool for cognitive impairment and dementia in elderly community dwellers.

OBJECTIVE: To identify which Instrumental Activities of Daily Living (IADL) are related to cognitive impairment, independent of age, sex, and education; to assess the performance of an IADL score using these items in screening for cognitive impairment and dementia in elderly community dwellers. DESIGN: Survey based on the baseline interview of the PAQUID study on functional and cerebral aging. SETTING: Community survey in 37 randomly selected parishes in Gironde, France. SUBJECTS: Random sample of 2,792 community dwellers aged 65 and over (participation rate: 69%). MEASUREMENTS: Two-phase screening: (1) functional assessment, Mini-Mental State Examination (MMSE) and DSM-III criteria for dementia; (2) in DSM-III-positive patients, NINCDS-ADRDA criteria applied by a neurologist. Functional assessment: IADL scale of Lawton and Brody. Criterion standards: cognitive impairment: MMSE score lower than 24; dementia: DSM-III and NINCDS-ADRDA criteria. RESULTS: Four IADL items are correlated with cognitive impairment independent of age, sex, and education: telephone use, use of means of transportation, responsibility for medication intake, and handling finances. A score adding the number of IADL dependencies has a sensitivity of 0.62 and a specificity of 0.80 at the lowest cut-off point (score > 0) for the diagnosis of cognitive impairment. The same score at the same cut-off has a sensitivity of 0.94 and a specificity of 0.71 for the diagnosis of dementia. The prevalence of dementia (2.4%) is reduced by a factor of 12 in subjects independent for the four IADL. CONCLUSION: The four IADL score could be incorporated into the screening procedure for dementia in elderly community dwellers.

Activities of Daily Living

The Paquid epidemiological program on brain ageing.

Paquid is an epidemiological study designed to gather and follow-up a cohort of 3,777 elderly subjects (65 years and older) living at home. In order to study normal and pathological brain ageing, these subjects were randomly chosen in the general population of 75 communities of Gironde and Dordogne, two administrative areas of South-Western France. The subjects were interviewed at home by trained psychologists and followed-up with the same procedure at 1, 3 and 5 years after the initial data collection. The identification of the demented cases is made with a two-stage design: the first stage is a systematic screening by the psychologists with application of the DSM-IIIR criteria and the second stage consists in a confirmation of the diagnosis by a neurologist according to the NINCDS-ADRDA criteria. Paquid is complemented by the study of a random sample of 357 subjects living in institutions in Gironde.

Activities of Daily Living

Occupation during life and memory performance in nondemented French elderly community residents.

Using data obtained during the baseline screening of the PAQUID cohort, an epidemiologic study on brain aging conducted in the Bordeaux area of France, we studied the relationship between lifetime occupation and memory performance in visual recognition (Benton Visual Retention Test; BVRT) and verbal induced recall (Wechsler Paired Associates Test; WPAT) in 2,720 elderly community residents. Occupational category was strongly correlated with poor memory performance for both the BVRT and the WPAT. Independent of the educational level, the risk of having poor memory performance was two to three times greater for farmers, domestic service employees, and blue-collar workers than for professionals/managerials. Occupational category should be taken into account in future cross-national studies on brain aging.

Aged

[Influence of educational status on a screening test for dementia, the Mini-Mental State Examination].

This study aimed to examine the relationships between the educational level and the Mini-Mental State Examination (MMSE) total scores and its different items. In a survey dealing with cerebral aging, the MMSE administered 2,792 subjects aged 65 years and over, who continued to live at home. The total score decreased with age and increased markedly when the educational level rose. The proportion of failures was higher than or equal to 10% for 12 of the 30 MMSE items, including the 5 items designed to measure attention ability (serial subtractions) and the 3 ones exploring delayed memory. Regarding these 12 items, the percentage of failures increased homogeneously with age, but the relationship with educational level was heterogeneous: it was very strong for the calculation items, weaker for the delayed memory items. These results pointed to the complex relationships between MMSE scores and educational level, and suggested a possible bias related to the screening tool in dementia surveys.

Aged

Intrauterine diagnosis of cytomegalovirus and rubella infections by amniocentesis.

OBJECTIVE: To establish a correlation between the presence of cytomegalovirus (CMV) or rubella virus in amniotic fluid obtained through amniocentesis and fetal infection. DESIGN: Case series. SETTING: Five hospitals in the Montreal region. Virology testing was done at the Virology Research Centre, Institut Armand-Frappier, Laval, Que. PATIENTS: Thirteen pregnant women infected with CMV, 3 with rubella, their 15 babies and 2 fetuses. Twelve of the women with CMV infection were recruited from a prospective study of CMV infection in pregnancy. Infection in the other women was detected through routine laboratory diagnostic testing. INTERVENTION: Amniotic fluid samples were cultured for CMV and rubella virus. Congenital infection of the neonates was established through isolation of either virus from pharyngeal mucus and urine specimens collected during the first 3 days of life or from fetal tissue if the pregnancy was terminated. MAIN RESULTS: CMV was cultured from the amniotic fluid of three of the CMV-infected women and from the pharyngeal mucus and urine specimens of their infants. Of the three women with rubella the amniotic fluid of one (who had a twin pregnancy) was positive for rubella virus. After the in-utero death of one fetus she underwent a therapeutic abortion of both. Examination of fetal tissue indicated that both fetuses had been infected with rubella virus. Each of the two other women with rubella gave birth to an uninfected, healthy infant. CONCLUSIONS: We found a strong correlation between the isolation of CMV or rubella virus from the amniotic fluid and the presence of congenital infection. This suggests that amniocentesis used to detect the presence of a virus is a useful method for the diagnosis of fetal infection.

Adult

Muscular mechanical energy expenditure as a process for detecting potential risks in manual materials handling.

The problem of injuries in manual materials handling remains a big concern in industrialized countries. It has become imperative in occupational biomechanics to extend the analyses to all pertinent factors involved in working tasks and to adopt an experimental approach leading to the understanding of the relative demands imposed simultaneously on all body joints. The evaluation of joint muscular work and the processes of energy generation, absorption and transfer appears promising as a tool in the detection of risk factors in working tasks. The present study consisted of evaluating two tasks (lifting and lowering) performed at five different heights (from 15 to 185 cm) with five different loads (from 3.3 to 22.0 kg). The subjects were eight experienced workers from a food product warehouse. Cinematography techniques and two AMTI force platforms were used to collect the data. Dynamic and planar segmental analyses were performed to calculate the net muscular moments at the joints, and work was calculated from the integration of muscular power. Factorial analyses of variance with repeated measures were performed on the dependent variables to evaluate the main effects of tasks, loads, and heights (for lifting and for lowering) and the interactions. The results revealed the adoption of different movement strategies in the handling of heavier loads. In the first, a larger emphasis of energy transfer and movement economy; in the second, a reduction in the relative contribution of the shoulders to the detriment of an increased participation of the lower back and hips was found. The comparison between lifting and lowering tasks indicated that lifting was only slightly more demanding than lowering for maximum muscular moments (about 15%) but much more so for mechanical work (about 40%); however, the nature of the efforts in eccentric contractions suggests that the lowering of heavy loads may be risky. Finally, the results revealed the deviation of height of handling from the waist level to be a significant factor. Handling at lower heights was considerably more demanding but the work was shared by several joints, mainly by the hips and lower back (about 70%); on the other hand, in handling above the waist, the work efforts were concentrated on the upper limbs (about 80%). In most cases, the participation of lower limbs was minimal and some movement strategies are suggested for future research.

Accidents, Occupational

Orientation and moment arms of some trunk muscles.

The orientations and moment arms of nine trunk muscles: latissimus dorsi, iliocostalis, longissimus dorsi, obliquii, rectus and transversalis abdominis, quadratus lumborum, and iliopsoas were obtained on embalmed specimens. Each muscle was considered as one or several, linear or curvilinear, lines of action. Origins, insertions, and points along the length of main bundles were digitized for each muscle using a three-dimensional digitizer. The results obtained from seven male specimens are presented and will permit more refined biomechanical models.

Abdominal Muscles

Defining clinically significant changes in the treatment of child stutterers.

This study established a clinically significant criterion to evaluate outcomes of children's stuttering therapy. 30 stutterers, ages 6 to 15 years, and 30 non-stutterers served as subjects. Speech samples were recorded and the percentage of stuttered syllables and rate of speech analyzed. According to Jacobson and Revenstorf's procedure, 3% of stuttered syllables and 160 syllables per minute should become the target behaviors in the treatment of children's stuttering.

Adolescent