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Biomedical subjects

M Bovenzi

Publications and source records attributed to M Bovenzi.

At least 55 records · Page 3Linked to original sources
PubMed1994

Hand-arm vibration syndrome and dose-response relation for vibration induced white finger among quarry drillers and stonecarvers. Italian Study Group on Physical Hazards in the Stone Industry.

OBJECTIVES: To investigate the occurrence of disorders associated with the hand arm vibration syndrome in a large population of stone workers in Italy. The dose-response relation for vibration induced white finger (VWF) was also studied. METHODS: The study population consisted of 570 quarry drillers and stonecarvers exposed to vibration and 258 control stone workers who performed only manual activity. Each subject was interviewed with health and workplace assessment questionnaires. Sensorineural and VWF disorders were staged according to the Stockholm workshop scales. Vibration was measured on a representative sample of percussive and rotary tools. The 8 h energy equivalent frequency weighted acceleration (A (8)) and lifetime vibration doses were calculated for each of the exposed stone workers. RESULTS: Sensorineural and musculoskeletal symptoms occurred more frequently in the workers exposed to vibration than in the controls, but trend statistics did not show a linear exposure-response relation for these disorders. The prevalence of VWF was found to be 30.2% in the entire group exposed to vibration. Raynaud's phenomenon was discovered in 4.3% of the controls. VWF was strongly associated with exposure to vibration and a monotonic dose-response relation was found. According to the exposure data of this study, the expected percentage of stone workers affected with VWF tends to increase roughly in proportion to the square root of A(8) (for a particular exposure period) or in proportion to the square root of the duration of exposure (for a constant magnitude of vibration). CONCLUSION: Even although limited to a specific work situation, the dose-response relation for VWF estimated in this study suggests a time dependency such that halving the years of exposure allows a doubling of the energy equivalent vibration. According to these findings, the vibration exposure levels currently under discussion within the European Community seem to represent reasonable exposure limits for the protection of workers against the harmful effects of hand transmitted vibration.

Adult↗
PubMed1993

Occupational exposure and lung cancer risk in a coastal area of northeastern Italy.

A case-control study of lung cancer and occupational exposure was conducted in a coastal area of Northeastern Italy where metallurgical and mechanical industries, docks and shipyards are located. Cases comprised 756 men who died of primary lung cancer in a 5-year period. Controls comprised 756 male subjects dying from other causes during the same period. Occupational exposures to lung carcinogens were assessed according to a job title-based approach, using two separate lists of industries/occupations recognized as being causally associated (list A) or suspected of being causally associated (list B) with lung cancer in humans. Exposure to asbestos was classified as absent, possible, or definite. After adjustment for cigarette smoking and place of residence, a significant association was found between lung cancer and occupations in both list A [relative risk (RR) = 2.25, 95% confidence interval (CI) = 1.68-3.03] and list B (RR = 1.33, 95% CI = 1.03-1.71). A significant excess risk was found for workers with definite exposure to asbestos as compared to those with no exposure to lung carcinogens (RR = 1.98, 95% CI = 1.42-2.75). Among occupations with recognized exposure to lung carcinogens other than asbestos, a significant excess risk for lung cancer was observed in iron and metalware workers. In occupational groups with definite exposure to asbestos, elevated risk estimates were found for shipyard workers, dockworkers, carpenters, and electricians. The combined effect of smoking and asbestos was found to be compatible with that expected under a multiplicative model. The overall population-attributable risk (ARp) for cigarette smoking was found to be 87.5%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1993

Digital arterial responsiveness to cold in healthy men, vibration white finger and primary Raynaud's phenomenon.

Finger systolic pressure (FSP) was measured during a standardized cold test in 291 healthy male subjects divided into five age groups. The age groups showed no difference in the change in FSP (FSP%) after cold provocation at 15 and 10 degrees C. In the entire population, the lower normal limits of FSP% were estimated as 76% at 15 degrees C and 63% at 10 degrees C. When a discriminating threshold of FSP%10 degrees < 60% was applied to the results of the cold test of 31 referents, 65 chain saw workers with or without vibration-induced white finger (VWF), and 20 male patients with primary Raynaud's phenomenon (PRP), the sensitivity of the test to detect digital vasospasm was 84% for VWF and 95% for PRP. In the chain-saw worker group, the positive and negative predictive values of the cold test were 94%. Therefore the measurement of FSP during cold provocation can be considered a useful laboratory test to confirm Raynaud's symptoms objectively in both groups and individuals.

Adult↗
PubMed1992

Self-reported low back symptoms in urban bus drivers exposed to whole-body vibration.

The prevalence of self-reported low back symptoms was investigated by a postal questionnaire in a group of 234 urban bus drivers exposed to whole-body vibration and postural stress and in a control group of 125 maintenance workers employed at the same bus municipal company. The average vertical whole-body vibration magnitude measured on the seat pan of the buses was 0.4 m/s2. After controlling for potential confounders, the prevalence odds ratios for the bus drivers compared to the controls significantly exceeded 1 for several types of low back symptoms (leg pain, acute low back pain, low back pain). The occurrence of low back symptoms increased with increasing whole-body vibration exposure expressed in terms of total (lifetime) vibration dose (years m2/s4), equivalent vibration magnitude (m/s2), and duration of exposure (years of service). The highest prevalence of disc protrusion was found among the bus drivers with more severe whole-body vibration exposure. Frequent awkward postures at work were also related to some types of low back symptoms. It is concluded that bus driving is associated with an increased risk for low back troubles. This excess risk may be due to both whole-body vibration exposure and prolonged sitting in a constrained posture. The findings of this study also indicated that among the bus drivers low back symptoms occurred at whole-body vibration exposure levels that were lower than the health-based exposure limits proposed by the International Standard ISO 2631/1.

Adult↗
PubMed1991

Occupational musculoskeletal disorders in the neck and upper limbs of forestry workers exposed to hand-arm vibration.

An epidemiologic and clinical study of neck and upper limb musculoskeletal disorders was carried out on 65 vibration-exposed forestry operators using chain-saws and 31 comparable control subjects (maintenance workers) performing manual activity and not exposed to vibration. Upper limb function was evaluated by measuring finger and wrist circumference size, maximal hand grip strength and range of motion manoeuvres in both the controls and the exposed workers. Vibration from two chain-saws was measured, and vibration exposure for each forestry worker was assessed in terms of 4 h energy-equivalent frequency-weighted acceleration according to ISO 5349. Job analysis indicated a slight excess risk of upper extremity cumulative trauma disorders (CTDs) in the forestry operators compared with the control workers. After adjustment for age and body constitution, significantly higher prevalence rates of persistent upper limb pain, muscle-tendon syndromes and carpal tunnel syndrome were observed among the forestry workers than among the controls. In the forestry operators, the occurrence of upper limb musculoskeletal disorders increased with increasing vibration exposure. Upper limb function was found to be impaired in the forestry workers compared with the controls. Vibration exposure was significantly related to increased finger circumference size, diminished muscle force and reduced joint function. Even though it is difficult to establish the relative importance of vibration and ergonomic factors in the aetiology of CTDs, nevertheless the results of this study indicate that musculoskeletal impairment to the upper limbs was more severe in the forestry operators than in the controls who did solely manual work. This finding and the observed dose-effect relationships suggest that vibration stress is an important contributor to the development of musculoskeletal disorders in workers using hand-held vibrating tools.

Adult↗
PubMed1991

Prognostic value of total ischemic burden in patients with stable ischemic heart disease.

Patients with stable coronary artery disease commonly have transient myocardial ischemia with or without experiencing angina, but the prognostic implications of this "total ischemic burden" is still a matter of debate. We studied 112 consecutive patients with coronary artery disease, normal left ventricular function at rest and exercise-induced myocardial ischemia, a 24-hour ambulatory EKG was performed after drug withdrawal. The mean exercise duration was 572 +/- 192 seconds, with an ischemic threshold (ST depression = 1 mm) of 390 +/- 190 seconds). By Holter monitoring 30 patients had no ischemia and 82 (73%) had a total of 332 episodes of ST segment changes, the majority of which were asymptomatic (242/332, 73%). Among 82 patients with transient myocardial ischemia, 44 (54%) had only asymptomatic episodes. Nine patients (11%) complained of angina coincident to ST changes. Twenty-nine patients (35%) had both painful and painless ST segment alterations. All patients were prospectively followed-up while on conventional medical therapy. During a mean follow up of 25 +/- 10 months cardiac events occurred in 31 patients; there were 5 cardiac deaths, 3 non-fatal myocardial infarctions, 2 hospitalization for unstable angina and 21 revascularization procedures (PTCA or CABG). By multivariate analysis the number of stenotic vessels on coronary angiography was predictive of the events during the follow-up (p = 0.03), while other demographic, clinical, ergometric and angiographic variables were not influential. Event-free survival was similar for all subsets of transient myocardial ischemia (silent, symptomatic, or none).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

Physiological reactions during brush saw operation.

An experimental study of the physiological effects of brush saw operation was performed on eight professional agricultural workers. The experiments were carried out in the field under practical working conditions. Aesthesiometric thresholds (two-point discrimination and depth sense perception), manipulative dexterity, pinch grip force and fingertip skin temperature (FST) were measured before and after exposure to different combinations of static load (handle holding), noise and vibration by using new production brush saws for 5 to 15 min. The changes in the peripheral circulatory, sensorineural and muscular functions of the brush saw workers were not found to be significantly different under the various exposure conditions. Static load accounted for the major part of the changes in aesthesiometric thresholds, pinch grip force and FST after brush saw operation. With respect to baseline measurements, no significant difference in manipulative skill was observed after each exposure period. The weighted vibration accelerations from the right and left handles of a brush saw were 3.13 and 1.80 m/s2, respectively. The assessment of brush saw vibration exposure according to ISO 5349 and the results of FST measurements were consistent with the findings of some epidemiological surveys indicating a low risk of vibration-induced white finger among brush sawyers. This investigation pointed out that the increase in the aesthesiometric thresholds was mainly determined by handle holding, and that the reduction in gripping force during actual work was related to the duration of brush saw operation. Therefore, prolonged static overload on the nerves, muscles and joints of the hand-arm system could explain the increased risk of musculoskeletal and sensorineural disorders found among brush saw users.

Adult↗
PubMed1990

Transient myocardial ischaemia: a multivariate analysis on clinical, angiographic and ergometric variables.

The availability of ambulatory ECG monitoring allows identification of transient myocardial ischaemia, the clinical relevance of which is currently being investigated. Ninety-four consecutive patients with ischaemic heart disease and a positive exercise test (greater than or equal to 1 mm ST-segment depression) were studied to evaluate the prevalence of transient myocardial ischaemia (either painless or painful) during 24-h dynamic electrocardiogram (ECG) and the clinical, angiographic and ergometric variables predicting its appearance. Two-hundred-and-eighty-one episodes of transient electocardiographic myocardial ischaemia were recorded in 69 patients (73.4% of all patients). Transient myocardial ischaemia was more frequent, although not significantly so, in patients with diabetes, with previous myocardial infarction, or with multivessel disease. When tested by multivariate analysis, neither the clinical variables nor the severity of coronary artery disease allowed prediction of the occurrence of transient myocardial ischaemia during dynamic ECG. The duration of exercise testing up to the ischaemic threshold (ST-segment depression = 1 mm) and the peak heart rate during exercise were more accurate predictors of transient myocardial ischaemia (P = 0.019 and 0.012 respectively). Patients with transient myocardial ischaemia had a lower ischaemic threshold (355 +/- 175 vs 498 +/- 150 s, mean +/- SD, P = 0.001) despite a lower peak heart rate (129 +/- 18 vs 137 +/- 12 beats min-1, P = 0.047) than patients without transient myocardial ischaemia. In conclusion, exercise testing may help select patients for examination by dynamic ECG.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Angiography↗
PubMed1990

Autonomic stimulation and cardiovascular reflex activity in the hand-arm vibration syndrome.

Two experiments were carried out to investigate the cardiovascular responses of vibration-exposed workers to autonomic stimulation. In the first experiment blood pressures, heart rate and systolic time intervals (STI) were measured during a cold test in 63 vibration-exposed foundry workers and 41 controls. STI, such as total electromechanical systole (QS2I) and left ventricular ejection time index (LVETI), were found to be shorter in the vibration-exposed workers with and without vibration white finger (VWF) than in the controls, both at rest and during cold provocation and recovery (p less than 0.001). A significant inverse relationship between urinary excretion of free catecholamines and the duration of STI was observed under resting conditions (0.001 less than p less than 0.03). In the second experiment, the above mentioned cardiovascular parameters were measured in 11 grinding operators with VWF and 11 controls during a hand grip test, an arithmetic test and an orthostatic test. Finger systolic pressures (FSP) during local cooling to 30, 15 and 10 degrees C were also measured. QS2I and LVETI were more abbreviated in the VWF subjects than in the controls at rest and during both the circulatory stress tests and the recovery periods (0.001 less than p less than 0.05). The reduction in FSP by local cooling from 30 degrees C to 15 and 10 degrees C was greater in the VWF workers than in the controls (p less than 0.001). Significant correlations were observed between the reduction in FSP at 15 and 10 degrees C and the duration of STI during circulatory stress activities (p less than 0.01). A multiple regression analysis pointed out that vibration exposure was the major determinant of STI during circulatory stress, while the importance of age and smoking and drinking habits in predicting STI was negligible. The findings of these studies suggest that the level of cardiac sympathetic activity is increased in VWF workers in comparison with controls. These experimental results are consistent with those of other investigators, indicating that excessive sympathetic reflex activity plays an important role in the pathogenesis of VWF.

Fingers↗
PubMed1990

[Evaluation of exercise test reproducibility in patients with ischemic cardiopathy].

We evaluated the repeatability of some measurements taken during the bicycle ergometer exercise test (exercise duration, heart rate and pressure rate product at angina and ST segment depression times) in 166 consecutive non-selected ambulatory patients with proven ischemic heart disease. One hundred and sixty-six patients with history of angina and/or myocardial infarction performed three exercise tests within seven days of wash-out. Eighty-six (58.1%) of these experienced angina and ischemic ST segment depression during all three tests (group 1), and 80 (48.2%) finished at least one test without angina or ST segment depression (group 2). The degree of angina (according to Canadian Cardiovascular Society classification) was higher in the first group than in the second one; on the contrary, exercise duration as well as pressure rate product at ischemic threshold, heart rate and pressure rate product at the onset of angina were significantly lower (0.001 less than p less than 0.05) in the former group. In group 1, we analyzed ergometric parameter measurement "repeatability" during the three consecutive exercise tests. The analysis of variance for repeated measurements showed that exercise duration and pressure rate product values at ischemic threshold did not vary significantly in the three tests, while other ergometric parameters showed a greater variability (0.001 less than p less than 0.05). Age, previous myocardial infarction or rest angina, the number of critically stenotic coronary vessels and the ejection fraction did not condition the repeatability of the test. In conclusion, in our population of non-selected ischemic patients only 52% developed angina and ischemic ST segment depression during all three exercise tests performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

Quantitative estimation of aesthesiometric thresholds for assessing impaired tactile sensation in workers exposed to vibration.

To evaluate the usefulness of aesthesiometric threshold testing in the quantitative assessment of peripheral sensorineural disorders occurring in the hand-arm vibration syndrome, two point discrimination (TPD) and depth sense perception (DSP) thresholds were measured by means of two aesthesiometers in the fingertips of 65 forestry workers exposed to chain saw vibration and 91 healthy males unexposed to local vibration or neurotoxic chemicals. Among the healthy subjects, divided into three age groups, there was no difference in the mean values of TPD and DSP thresholds. Assuming 1.28 or 2 standard deviations above the mean to be the upper limits of normality, in the present study the threshold values for TPD were 2.5 and 3.13 mm, respectively. Using the same assumptions, the normal threshold values for DSP were 0.36 and 0.49 mm. Among the 65 chain saw operators the prevalence of peripheral sensory disturbances was 70.8%. On the basis of the aesthesiometric results obtained for the group of 46 chain sawyers affected with sensorineural symptoms and a control group of 46 manual workers, the specificity of the aesthesiometric testing method was found to range between 93.4 and 100%, while the sensitivity varied from 52.2 to 71.7%. In its predictive value aesthesiometry had a positive accuracy of 84.6-96.0% and a negative accuracy of 42.8-50.0%. Aesthesiometric testing was able to differentiate between normals and vibration workers with sensory disturbances on a group basis (P less than 0.001), but due to the high rate of false negatives among vibration exposed patients, it was unsuitable to confirm objectively sensorineural symptoms on an individual basis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Cardiovascular responses to autonomic stimuli in workers with vibration-induced white finger.

Cardiovascular responses to autonomic stimulation were assessed in 11 grinding operators affected with vibration-induced white finger (VWF) and in 11 comparable healthy controls by measuring blood pressures, heart rate and systolic time intervals (STI) during a hand-grip test, an arithmetic test and an orthostatic test. Digital circulatory function was also investigated by measurement of finger systolic pressure (FSP) during local cooling with water at 30 degrees C, 15 degrees C and 10 degrees C. The increase in diastolic blood pressure and heart rate during the stress tests was greater in the VWF workers than in the controls. The STI values such as total electromechanical systole and left ventricular ejection time, were found to be shorter in the VWF subjects than in the controls at rest and during both the circulatory stress tests and the recovery periods (0.001 less than p less than 0.05). Multiple regression analysis showed that vibration exposure was the major predictor of STI during the stress tests, while age, smoking and drinking habits did not contribute substantially to the explained variation in STI. The reduction in FSP by local cooling from 30 degrees C to 15 degrees C and 10 degrees C was greater in VWF operators than in controls (p less than 0.001), and total closure of the digital arteries at 10 degrees C was observed in 8 VWF workers (72.7%). In all subjects significant relationships were found between the reduction in FSP at 10 degrees C and the decrease in STI during circulatory stress activities (p less than 0.001). The findings in this study suggest an association between vibration exposure, digital vasospasm and increased cardiac sympathetic tone, the latter being demonstrated by the shortening of STI during the stress tests. It is suggested that excessive sympathetic reflex activity plays the dominant role in the pathogenesis of VWF.

Adult↗
PubMed1988

Vibration white finger, digital blood pressure, and some biochemical findings on workers operating vibrating tools in the engine manufacturing industry.

A clinical and laboratory investigation was carried out on 76 operators using pneumatic hand grinders and impact wrenches in the engine manufacturing industry. Twenty-two vibration-exposed workers (28.9%) had no symptoms in the hands (stage 0 of the Stockholm Workshop scale), 34 (44.7%) were affected with sensorineural disturbances in the fingers (stage SN), and 20 (26.3%) suffered from vibration white finger (VWF stages 1-2-3). In the vibration-exposed operators and in 30 comparable referents not exposed to vibration, finger systolic blood pressure (FSP) was measured on a test finger and on a control finger after digit cooling to 30 degrees C and 10 degrees C. The results of the cold provocation test were expressed as percent change of FSP by cooling the test finger from 30 degrees C to 10 degrees C (FSP%t, 10 degrees) and as digital/brachial pressure index during local cooling at 10 degrees C (DPIt, 10 degrees). After cold provocation the mean values of FSP%t, 10 degrees and DPIt 10 degrees were more significantly reduced in the vibration-exposed workers with VWF than in those without VWF and the referents (p less than 0.001). The cold provocation test was found to differentiate between VWF subjects with stages 1-2 and stage 3 (p less than 0.02). It is concluded that the measurement of FSP combined with finger cooling is a useful laboratory test to diagnose objectively Raynaud's phenomenon of occupational origin. The vibration-exposed workers and the referents were also tested for serum levels of immunoglobulins and complement and for daily excretion of urinary free catecholamines. Between the reference and vibration groups no differences in the mean values of the immunologic parameters and urinary catecholamines were found. The meaning of these findings is discussed.

Adult↗
PubMed1988

Finger systolic pressure during local cooling in normal subjects aged 20 to 60 years: reference values for the assessment of digital vasospasm in Raynaud's phenomenon of occupational origin.

Measurements of finger systolic pressure (FSP) during a standardized cold test (finger cooling to 30, 15 and 10 degrees C during 5 min ischemia) were performed on 103 healthy subjects divided into four subgroups according to age: 20-29 years (n = 22), 30-39 years (n = 32), 40-49 yr (n = 27), 50-60 years (n = 22). Among the age groups there was no difference in the reduction of FSP (FSP%) and in the digit-to-brachial systolic pressure index (DBI%) after cold provocation at 15 and 10 degrees C. Cold-induced digital vasoconstriction was more intense in smokers than in non smokers (P = 0.025). In the entire study population the lower normal limits of FSP% were 74% at 15 degrees C and 63% at 10 degrees C. Using an FSP%10 of less than 60% as a discriminating threshold between normals and patients with vibration white finger, the sensitivity of the cold test was 87% and the specificity was 100%. The findings of this study suggest the following considerations: (a) age does not seem to influence the digital arterial response to cold in healthy subjects; (b) smoking has a harmful effect on finger cold reaction in normal individuals; (c) the measurement of FSP during cooling is an accurate method of objectively diagnosing Raynaud's phenomenon of occupational origin.

Adult↗
PubMed1988

Prevalence of vibration-induced white finger and assessment of vibration exposure among travertine workers in Italy.

Among 76 stonedrillers and stonecutters/chippers working in the Rapolano travertine quarries (Tuscany, Italy), 27 subjects (35.5%) were affected with vibration-induced white finger (VWF). The median latent period for VWF was ten years (range 0.1-26 years). A VWF prevalence of 8% was found among 60 comparable controls (P less than 0.0001). Vibration measurements showed that the frequency-weighted accelerations for two rock-drills and two small chipping hammers ranged from 19.7 to 36.4 m/s2. Weighted accelerations between 2.4 and 4.1 m/s2 were measured on the handles of a vertical grinder and a hand cutter. Vibration data, daily exposure time and total duration of exposure period were used to calculate two indicators of vibration dose such as the four-hour, energy-equivalent, frequency-weighted acceleration (m/s2) and the vibration exposure level (dB). A significant association between the vibration exposure level and the severity of VWF stages was observed among the travertine operators. The dose-effect relationship proposed by ISO 5349 was not suitable for the data of the present study because it overestimates the risk due to hand-transmitted vibration in the travertine workers. Finally, the results of a cold test indicated that the rewarming time of fingertips to room temperature was more prolonged in the operators with VWF than in those without VWF and in the controls.

Cold Temperature↗
PubMed1987

Bone and joint disorders in the upper extremities of chipping and grinding operators.

X-ray examinations of the wrists, the elbows and the shoulders were carried out on 67 vibration-exposed foundry workers and on 46 comparable referents performing heavy manual work. Both groups had a mean age of 39.6 years. Musculoskeletal symptoms, such as arthralgias of the wrist and elbow joints, muscle pain and decreased muscular force, were found to be significantly increased in the chipping and grinding workers compared with the referents. After adjustment for age, the prevalence of cysts in the metacarpal and carpal bones was almost the same in the two groups, whereas radiological signs of osteoarthritis in the wrist joint were more frequent among the vibration-exposed workers (P less than 0.025). The overall prevalence of radiographic abnormalities in the elbow joint was higher in the vibration group than in the reference group (P less than 0.025). Olecranon spurs were observed in 50.7% of the exposed operators and in 28.2% of the referents (P less than 0.025). No difference in the prevalence of radiological changes in the should could be demonstrated between the populations studied. In both groups injuries of bones and joints were not associated with age. Among the chipping and grinding operators, a slight but not significant trend in the prevalence of skeletal abnormalities with increasing vibration exposure was observed. The results of this study indicate that the foundry workers using vibrating tools were affected with bone and joint disorders in the elbow and, to a lesser extent, in the wrist, which occurred more frequently than was observed in unexposed referents, who performed solely heavy manual activity. Among the vibration-exposed workers, no relationship between radiological changes in the upper limbs and symptoms of vibration white finger was found, pointing out that different pathogenic mechanisms are involved.

Adult↗