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Biomedical subjects

I Vuori

Publications and source records attributed to I Vuori.

At least 19 recordsLinked to original sources
PubMed1992

A cruciate ligament injury produces considerable, permanent osteoporosis in the affected knee.

Bone mineral density (BMD) and clinical status of 42 patients treated surgically 10-11 years earlier for an acute knee ligament injury were determined. The BMD was measured at the spine (L2-4) and the femoral neck, distal femur, patella, proximal tibia, and calcaneus of both lower extremities using dual-energy x-ray absorptiometric (DXA) scanner. The relative BMD results of the injured knee were correlated with sex, age, activity level, knee stability, and functional scores of the patient. In the 11 patients with moderate injury (isolated rupture of the medial collateral ligament), the BMDs of the injured and uninjured extremities were equal. In the 31 patients with severe injury (cruciate ligament rupture), the BMDs were significantly lower in the injured knee: distal femur, -6.0% (p = 0.0000); patella, -9.0% (p = 0.0000); and proximal tibia, -3.3% (p = 0.0012). Neither the femoral neck nor the calcaneus showed any differences. There were no significant differences either between men and women or between patients with different activity levels. The relative BMDs of the injured knee did not correlate with age or static knee stability but correlated significantly (r = 0.42-0.78, p < 0.01-0.001) with the functional scores of the same knee: the better the knee function in comparison with the healthy knee, the higher the relative BMD. The spinal BMDs corresponded with the age-adjusted reference values of the used densitometry. In conclusion, a severe knee ligament injury results in permanently decreased BMD in the injured knee. Other parts of the same extremity and lumbar spine are not affected.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗
PubMed1992

Evaluation of a model for prediction of lumbar bone mineral density.

A mathematical model with adequate clinical accuracy would be useful for predicting life-long bone mass behaviour in various skeletal sites. We have tested the performance of a multivariate nonlinear model, recently developed by an Italian research group for predicting lumbar bone mass and density, in a sample of 239 pre- or post-menopausal healthy Finnish women whose lumbar bone mineral density (BMD) was determined by dual-energy X-ray absorptiometry. The model, which was based on height, weight, body mass index, age and years since menopause, predicted poorly (R-squared = 0.14) the measured BMD. Furthermore, it compressed strongly the actual variation of the BMD values resulting in a considerable overestimation or underestimation (about 30%) of low or high BMD values, respectively. Our results indicated that the predictive value of a simple model is not clinically acceptable and therefore the usefulness of this kind of model remains questionable.

Absorptiometry, Photon↗
PubMed1992

Daytime sleepiness: a risk factor in community life.

The prevalence of daytime sleepiness and background factors associated with it were investigated in a study carried out at the UKK Institute. The inquiry took the form of a questionnaire mailed to 1600 people of middle age. Daytime sleepiness was found to be associated with disturbed night sleep. Women were more tired than men, but men slept more frequently during the day. Those suffering from tiredness complained of poor health more than other respondents. Traffic accidents and other mishaps attributable to tiredness had occurred in 1.3% of cases, and almost 5% of male respondents had dozed off while driving at least five times in their lives. The findings indicate a need for increased attention to disturbance of sleep and daytime sleepiness in routine health screening.

Accidents, Traffic↗
PubMed1992

Validity of a two kilometre walking test for estimating maximal aerobic power in overweight adults.

In our earlier study a regression model, with heart rate and time in a 2 km fast walk, body mass index (BMI) or weight (kg) and age as explanatory variables, explained 75% of the variation in the VO2max of adults with normal weight. The present study was designed to test whether the prediction model based on a 2km fast walk and simple site measurements is valid in estimating the VO2max of overweight men and women and to compare 1km and 2km test distances. Forty-five women and thirty-two men, BMI 27-40, aged 20-65 years, with no cardiorespiratory or musculoskeletal restrictions for a maximal stress test and fast walk, were studied. The VO2max was determined in an uphill walk to maximal effort on a treadmill. Two walking tests, 1km and 2km, were conducted on a flat dirt road. Heart rate was recorded during the walks, and the mean rate during the last 30 seconds was used in the model. The correlation coefficients between the measured and predicted VO2max in the 2km test were 0.77 for the women and 0.75 for men, corrected for body weight (ml/kg/min), and 0.77 and 0.69 respectively in absolute values (1/min). These results suggest that the 2km walk test previously developed for adults within normal weight limits is a reasonably valid test of the cardiorespiratory fitness of overweight, but otherwise healthy, women and men.

Adult↗
PubMed1992

Precision of dual-energy x-ray absorptiometry in determining bone mineral density and content of various skeletal sites.

Repeated measurements of bone mineral density (BMD) by dual-energy x-ray absorptiometry (DEXA) reliably indicate changes in the bone mineral content (BMC) of the lumbar spine and proximal femur, but its applicability to other sites has not been properly determined. The in-vivo day-to-day precision of DEXA (Norland XR-26) for lumbar spine, femoral neck, distal femur, patella, proximal tibia, calcaneus and distal radius was evaluated for 15 subjects who were scanned three times for 2 wk. Intra- and interobserver errors were also determined for image analysis. For clearly defined regions of interest, the following precision values were obtained for BMD with low intra- and interobserver error: 1.7% (lumbar spine), 1.3% (femoral neck), 1.2% (distal femur), 1.0% (patella), 0.7% (proximal tibia), 1.3% (calcaneus) and 1.9% (distal radius). The precision for BMC was lower. The results indicate that DEXA can successfully and precisely measure BMD of sites not commonly assessed by this technique.

Absorptiometry, Photon↗
PubMed1991

Improved diagnostic performance of the exercise ECG test by computerized multivariate ST-segment/heart rate analysis.

The exercise ECG test is the most widely used noninvasive method of evaluating myocardial ischemia. To determine whether it is possible to enhance its diagnostic power, the authors carried out computerized ECG measurements on 118 nonischemic patients and 38 ischemic patients with or without myocardial infarctions (MIs). Forty-seven (all ischemic and nine normal cases) underwent T1-201 SPECT. The diagnostic variables include ST-segment deviation, modified ST/HR-slope, ST-segment shape, and maximum heart rate. These variables are interrelated by means of compartmental and specific decision rules by computer. The diagnostic method discussed in this article is called the multivariate ST/HR analysis (MUSTA). When compared with MUSTA, the T1-201 SPECT images detected myocardial ischemia with a sensitivity of 100% and a specificity of 89%. Its diagnostic performance was influenced by neither previous MIs nor cardiac medication of the 47 patients tested. MUSTA was also compared to the nonmodified ST/HR analyses (ST60/HR and ST80/HR) and the standard exercise ECG test. It performed significantly better than these methods. The authors conclude that the multivariate ST/HR analysis is comparable to T1-201 SPECT in diagnosing myocardial ischemia among the study subjects. Furthermore, MUSTA is executed during the noninvasive exercise ECG test and is easily applied using an IBM/AT-compatible microcomputer. However, further evaluation of MUSTA with a separate and unselected patient population is needed.

Adult↗
PubMed1991

A 2-km walking test for assessing the cardiorespiratory fitness of healthy adults.

A simple walking test was developed with 159 (females = 80, males = 79) healthy 20-65-year-old subjects. All the subjects first walked the distances of 1.0, 1.5 and 2.0 km on a flat dirt road. Half of the participants were tested in the laboratory for maximal oxygen uptake (VO2max), and the 2-km test was repeated again twice. In a comparison of the three distances, the 2-km test was repeatable, the most preferable subjectively and the most accurate in predicting VO2max. A sex-specific prediction model including walking time, heart rate at the end of the walk, age and body mass index predicted 73-75% of the variance in VO2max (ml.kg-1.min-1) and that with body weight 66-76%, with a standard error of estimate of the order of 9-15% of the mean. The cross-validation of the models yielded reasonable accuracy in obese men and women and in moderately active men, and less accuracy in moderately active women and highly active men. These results suggest that a fast 2-km walk supplemented with simple measurements is a feasible and accurate alternative for determining the cardiorespiratory fitness of healthy adults.

Adult↗
PubMed1989

Haemodynamic and hormonal responses to heat exposure in a Finnish sauna bath.

Eight healthy young men were studied during three periods of heat exposure in a Finnish sauna bath: at 80 degrees C dry bulb (80 D) and 100 degrees C dry bulb (100 D) temperatures until subjective discomfort, and in 80 degrees C dry heat, becoming humid (80 DH) until subjective exhaustion. Oral temperature increased 1.1 degrees C at 80 D, 1.9 degrees C at 100 D and 3.2 degrees C at 80 DH. Heart rate increased about 60% at 80 D, 90% at 100 D and 130% at 80 DH. Plasma noradrenaline increased about 100% at 80 D, 160% at 100 D and 310% at 80 DH. Adrenaline did not change. Plasma prolactin increased 2-fold at 80 D, 7-fold at 100 D and 10-fold at 80 DH. Blood concentrations of the beta-endorphin immunoreactivity at 100 D, adrenocorticotropic hormone (ACTH) at 100 D and 80 DH, growth hormone at 100 D and testosterone at 80 DH also increased, but cortisol at 80 D and 100 D decreased. The plasma prostaglandin E2 and serum thromboxane B2 levels did not change. Patterns related to heat exposure were observed for heart rate, plasma noradrenaline, ACTH and prolactin in the three study periods.

Adult↗
PubMed1989

Prognostic value of an exercise test one year after myocardial infarction.

An exercise test was performed in 306 patients who had had acute myocardial infarction one year previously. The five year cumulative coronary heart disease mortality was 40.0%, when the test had to be discontinued because of ventricular arrhythmias but only 13.0% if discontinued because of fatigue (P less than 0.05). If the maximum work load was less than 80 W the mortality was 30.7% compared with 16.6% in patients who exercised at least 80 W (P less than 0.01). If maximum systolic blood pressure was less than or equal to 150 mmHg mortality was 40.3% compared with 8.5% in patients with greater than 200 mgHg (P less than 0.001). The mortality was 38.2% in patients having single monoform ventricular ectopic beats at a rate of three or more per minute or multiform, paired or early cycle ventricular ectopic beats or ventricular tachycardias: this compared with 14.1% (P less than 0.001) in patients having no or only single monoform ventricular ectopic beats at a rate of less than three per minute. ST-segment depression in univariate testing had no prognostic value. When both exercise test and clinical variables were used in survival analysis (Cox's regression) the most important variable was heart volume and after that ventricular arrhythmias. In multivariate regression analysis ST segment depression also had additional prognostic value. Thus ventricular arrhythmias turned out to be the most important prognostic factor measured during exercise test.

Aged↗
PubMed1989

A new fitness test for cardiovascular epidemiology and exercise promotion.

The present study suggests that the 2-km walking test is relatively simple to administer by trained instructors, it is as accurate in predicting VO2 max as most available indirect methods, and it is socially acceptable for a normal population. Thus, the test seems to provide a feasible alternative for the testing of cardiovascular fitness in epidemiological research and exercise promotion.

Adult↗
PubMed1988

Self-evaluations of factors promoting and disturbing sleep: an epidemiological survey in Finland.

The purpose of this epidemiological survey (N = 1600) was to describe the factors which middle-aged urban people in Finland perceived as promoting or disturbing sleep. The response rate was 75%. The results suggested that quality of sleep is determined by numerous factors; social and psychological factors, health status, external sleeping conditions, life style and living habits. Every third respondent felt that exercise had a positive impact on sleep. Second in importance were reading and listening to music. Furthermore, sauna, shower and bath, stability in life, psychological factors, positive experience in work, satisfactory sexual life and good and quiet sleeping environment were reported to have positive effects on sleep. Men considered work-related pressure and fatigue (20%) as the most important factor disturbing falling asleep or quality of sleep. In women's ranking work problems appeared no sooner than in the third place. Women reported worries, interpersonal problems, and marital and family discord as the most disturbing factors to sleep (37%). Coffee in the evening had a negative effect on falling asleep. Although a 'nightcap' was considered to improve relaxation on falling sleep, men ranked alcohol as the fourth disturbing factor. Other disturbing factors were stress, irregularities in everyday life because of social events, travelling or atypical catnaps. Eating and exercising too heavily or too late in the evening were found to disturb sleep. On the other hand, temporary lack of exercise seemed to impair the quality of sleep. As external factors disturbing sleep the subjects considered noise light, too high room temperature, tight clothing, unfamiliar sleeping environment and restless children.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Cardiorespiratory strain of middle-aged men in mass events of long-distance cycling, rowing, jogging, and skiing.

The heart rate of 11 39- to 53-year-old regularly exercising but nonathletic men was recorded during mass events of 132-km cycling, 35-km rowing, 33-km running, and 90-km cross-country skiing during 1 year. These measurements were related to the cardiorespiratory response in respective maximal exercise tests to determine and compare the strain of the four events. The mean event time of the subjects was 4 h 58 (+/- 34) min for cycling, 4 h 20 (+/- 35) min for rowing, 3 h 30 (+/- 29) min for running, and 8 h 29 (+/- 49) min for skiing. The respective mean heart rates were 153 (+/- 10), 137 (+/- 15), 159 (+/- 8), and 145 (+/- 5) bts/min, which represented 79.3 (+/- 6), 72.9 (+/- 13), 85.7 (+/- 4), and 72.8 (+/- 7) %VO2 max as determined from the event-specific HR/VO2 regression line. The proportion of event heart rates above the level representing the 90% event-specific maximal heart rate was 31.2% (+/- 19%) in cycling, 17.9% (+/- 26%) for rowing, 59.7% (+/- 24%) for running, and 21.6% (+/- 23%) for skiing. A statistical comparison of the mean event heart rates indicated that heart rate was lower in rowing than in jogging (P less than 0.01) and in cycling (P less than 0.05) and also lower in skiing (P less than 0.01) than in jogging. The present results showed that the cardiorespiratory strain of middle-aged nonathletic men during long-distance mass events of cycling, jogging, and skiing is high and relatively comparable to that of well-conditioned athletes.

Adult↗
PubMed1988

Sauna bather's circulation.

Cutaneous circulation increases greatly in sauna in order to prevent body heating. Blood pressure tends to fall but this is prevented by increased cardiac output by means of faster heart rate and by decreased blood flow to the visceral organs. Cooling in cold air, shower, water or rolling in snow causes rapid cutaneous vasoconstriction, which leads to elevation of arterial blood pressure and increase of central venous blood volume. The effects of both heat and cold are mediated via the sympathetic nervous system. The circulatory responses to sauna are related to the intensity and duration of the heat exposure. An ordinary sauna bath increases cardiac workload about as much as moderate or vigorous walking. Habituation to sauna decreases the sympathetic stimulation and cardiovascular responses. Sudden cooling, for example diving in cold water, causes a severe transitory volume load and pressure load to the heart and increases the possibility of cardiac arrhythmias. The risk of cardiovascular complications in correctly practiced sauna bathing is very small and it is confined to subjects predisposed to the risk because of manifest or latent cardiovascular abnormalities.

Blood Circulation↗
PubMed1988

Epidemiology of exercise effects on sleep.

This survey was designed to study the characteristics of sleep and perceived factors promoting and disturbing sleep. Several living habits, such as exercise, and characteristics of sleep were investigated independently of each other by a pretested questionnaire and a sleep diary which were mailed to a stratified random sample of 200 men and women in each of the age groups 36, 41, 46 and 50 years (N = 1600). The response rate was 75%. Every third respondent felt that exercise (e.g. jogging and evening walks) had a positive impact on sleep quality. The most frequently perceived positive effects of exercise were ease of falling asleep, deepness of sleep, a sense of wellbeing and more alertness in the morning. Negative perceived effects of exercise were uncommon. The balance of positive and negative perceived effects of exercise was more favourable when the activity was performed early in the evening compared to late at night. When both the intensity and the timing of exercise were considered, light and moderate exercise, especially early in the evening, had mainly positive effects on sleep. The frequency of negative impacts increased when the exercise was performed vigorously late at night. However, a considerable portion of vigorous late exercisers reported mainly positive effects. The available information suggests that especially light and moderate exercise early in the evening should be emphasised in health education as a means to enhance sleep and to improve its quality. However, the epidemiological information about exercise and sleep should be investigated and verified in detail using objective methods and controlled interventions.

Adult↗