Biomedical subjects

S R Lord

Publications and source records attributed to S R Lord.

At least 55 records · Page 3Linked to original sources

PubMed1995

Physiologic, health and lifestyle factors associated with femoral neck bone density in older women.

Three hundred eleven women aged between 60 and 91 years (mean age 72.2) who were randomly recruited from the community underwent bone density assessments of the femoral neck. Two complementary multivariate techniques were used to assess the relationships between femoral neck bone density and a range of anthropometric, health, and lifestyle measures. Stepwise multiple linear regression analysis revealed age, weight, height, quadriceps strength, and lifelong smoking to be variables that independently and significantly explained part of the variance in femoral neck bone density within the group. Multiple logistic regression revealed that after adjusting for established predictors of bone mineral density, age, height, and weight, reduced quadriceps strength, lifelong smoking, and little childhood activity were significantly associated with low bone density (< 0.70 g/cm2), whereas superior quadriceps strength, nonsmoking, and high levels of current physical activity were significantly associated with high bone density (> 0.84 g/cm2). In contrast, current calcium intake was not significantly associated with bone density. The study findings highlight possible public health initiatives for minimizing age-related femoral neck bone loss in older women.

Aged↗

PubMed1995

Predictors of adherence to a structured exercise program for older women.

This study examined whether psychological, physiological, and health and lifestyle measures were associated with adherence to a structured exercise program for older women. Women aged "60 to 85 years (N = 102)," randomly recruited from the community, were assessed on these measures before and after a 12-month exercise trial. Sixty-nine women completed the trial, and 54 continued participation after the trial for at least 6 months. Adherence was examined at various stages during the trial. Multiple regression analysis revealed that reduced muscle strength, slow reaction time, and psychoactive drug use explained most of the variance in adherence during the trial. In contrast, muscle strength, reasoning ability, depression, and self-reported improvement in strength best predicted continued participation after the trial. The findings have implications for community-based exercise programs and research trials.

Aged↗

PubMed1995

Psychoactive medication use, sensori-motor function and falls in older women.

1. A 1 year prospective study was undertaken to identify possible mediating physiological mechanisms for the association between psychoactive medication use and falls in 414 women aged 65 to 99 years (mean age 73.7 years, s.d. = 6.3) who were randomly selected from the community. 2. Women taking certain psychoactive medications showed impaired performance in a number of sensori-motor measures, including tactile sensitivity, lower limb muscle strength, reaction time and balance control compared with women not taking these medications. Those using psychoactive medications were also comparatively inactive--taking part in only 1.1 h of planned exercise per week compared with 2.6 h for non-users (F = 12.44, df = 1,412, P < 0.01). 3. Multiple logistic regression analysis revealed that use of long-acting benzodiazepines (OR = 7.03, 95% CI = 2.12-23.28) and antidepressants (OR = 2.84, 95% CI = 1.00-8.02) was significantly associated with multiple falls, whilst adjusting for age, other drug category use, frequency of alcohol use, and number of medical conditions. Use of any two psychoactive medications was also significantly associated with falling frequency (Chi-square = 13.91, df = 1, P < 0.01). 4. Path analysis revealed a significant direct association (P < 0.001) between psychoactive medication use and falls, and a significant indirect association mediated via reduced physiological functioning (P < 0.001). Postural hypotension was not significantly associated with falls (RR = 1.37, 95% CI = 0.84-2.22). 5. The findings suggest that psychoactive medication use may predispose older people to falling by impairing important sensori-motor systems that contribute to postural stability.

Accidental Falls↗

PubMed1995

The effect of a 12-month exercise trial on balance, strength, and falls in older women: a randomized controlled trial.

OBJECTIVE: To determine whether a 12-month program of regular exercise can improve balance, reaction time, neuromuscular control, and muscle strength and reduce the rate of falling in older women. DESIGN: A randomized, controlled trial of 12 months duration. SETTING: Conducted as part of the Randwick Falls and Fractures Study in Sydney, Australia. PARTICIPANTS: One hundred ninety-seven women aged 60 to 85 years (mean age 71.6, SD = 5.4) who were randomly recruited from the community. OUTCOME MEASURES: Accidental falls, postural sway, reaction time, neuromuscular control, and lower limb muscle strength. MAIN RESULTS: Exercise and control subjects were tested before, midway through, and at the end of the trial. At initial testing, exercisers and controls performed similarly in all tests and were well matched in relevant health and lifestyle factors. The mean number of classes attended for the 75 exercise subjects who completed the program was 60.0 (range 26-82). At the end of the trial, the exercise subjects showed improved performance in all five strength measures, in reaction time, neuromuscular control, body sway on a firm surface with the eyes open, and body sway on a compliant surface with the eyes open and closed. In contrast, there were no significant improvements in any of the test measures in the controls. In one test measure, hip flexion strength, the exercisers showed continued improvement throughout the study year. There was no significant difference in the proportion of fallers between the exercise and control subjects. Interesting trends were evident, however, between falls frequency and adherence to the exercise program. CONCLUSIONS: These findings show that exercise can produce long-term benefits with regard to improving sensorimotor function in older persons. The findings also suggest that high compliance to an exercise program may reduce falls frequency, although further studies are required to conclusively demonstrate that exercise offers an effective means of preventing falls.

Accidental Falls↗

PubMed1995

Osteoarthritis, bone density, postural stability, and osteoporotic fractures: a population based study.

OBJECTIVE: Osteoarthritis (OA) is associated with an increase in bone density both locally and at distant sites. Prospective data are limited on the relationship between OA and fracture. We studied the possible relationship between self-reported OA, bone density, postural stability measures, and atraumatic fractures as part of a study of men and women over 60 years of age. METHODS: Subjects were part of the Dubbo Osteoporosis Epidemiology Study (a longitudinal population based study of fracture risk factors). Bone density was measured by dual energy x-ray absorptiometry. Postural stability was assessed by the validated measures of quadriceps strength and sway. Medication use and self-reported arthritis were assessed by a structured personal interview. Fractures were ascertained retrospectively by interview and prospectively by viewing radiographic reports for fracture. RESULTS: Among a study population of 1101 women and 720 men (mean age 69) there were 462 subjects (25%) who reported a diagnosis of OA. In both sexes, subjects with OA had higher bone density (adjusted for age and body mass index) at both the femoral neck (men, p = 0.026; women, p = 0.048) and lumbar spine (men, p = 0.0007; women, p = 0.0007). However, in both sexes, those with self-reported OA also had higher body sway and lower quadriceps strength. The combination of these observed differences in fracture risk factors led to no predicted change in fracture risk overall when using established nomograms for this population [men, OR = 1.11 (95% CI 0.83-1.45); women, OR = 1.08 (95% CI 0.83-1.39)]. This paralleled our observational finding that self-reported OA was not associated with a decrease in fracture incidence compared to those not reporting OA in both men (RR 0.64, 95% CI 0.29-1.39) and women (RR 1.00, 95% CI 0.66-1.51). CONCLUSION: Individuals with self-reported OA, despite higher bone density, are not protected against nonvertebral osteoporotic fracture, apparently due to worsened postural stability and thus an increased tendency to fall.

Aged↗

PubMed1994

Postural stability, falls and fractures in the elderly: results from the Dubbo Osteoporosis Epidemiology Study.

OBJECTIVE: To assess measures of postural stability in a large population of persons aged over 60 years in order to compare performance between fallers and non-fallers and relate postural stability to fracture prevalence. METHODS: The sensorimotor, visual and balance functions were measured in 1762 ambulatory, community-dwelling patients aged between 60 and 100 years (mean age, 70.1 years) living in a large semi-urban Australian city. A history of recent falls and fractures was recorded at the time of assessment. RESULTS: The prevalence of impairment in all tests increased with age. Men performed significantly better than women in tests of muscle strength, visual field dependence, sway on the floor with eyes open and dynamic balance. In the 12 months before testing, 72.3% of the patients experienced no falls, 18.4% fell only once and 9.3% fell on two or more occasions. Multiple fallers had weaker quadriceps, poorer tactile sensitivity, greater visual field dependence and greater body sway than other patients. Test scores for once-only fallers were mostly between those for non-fallers and multiple fallers. Those who suffered recent fall-related fractures had significantly reduced tactile sensitivity and quadriceps strength and increased body sway. Postural stability was also impaired in patients taking psychoactive and/or anti-hypertensive medications. CONCLUSION: Tests of postural stability can identify, independently of age, individuals living in the community who are at risk of falls and fall-related fractures.

Accidental Falls↗

PubMed1994

Physical activity program for older persons: effect on balance, strength, neuromuscular control, and reaction time.

Regular exercise has been recommended to improve balance, strength, and coordination in older persons. In this study, 44 persons, aged 50 to 75 years (mean 62.4 yrs) underwent assessments of quadriceps strength, reaction time, neuromuscular control, and body sway on two occasions before beginning a 10-week exercise program. The subjects were retested for the same measures at the end of the program. The mean number of classes attended for the 40 subjects who were retested was 16.2 (range 11 to 19). On completion of the program, the subjects showed improved performance in the tests of quadriceps strength, reaction time, body sway on a firm surface with the eyes closed, and a compliant surface with the eyes open and closed. In contrast, a group of nonexercisers showed no improvements in any of the test measures. These results suggest that exercise may play a role in improving a number of sensorimotor systems that contribute to stability in older persons.

Aged↗

PubMed1994

Physiological factors associated with falls in older community-dwelling women.

OBJECTIVE: To determine the prevalence of impaired vision, peripheral sensation, lower limb muscle strength, reaction time, and balance in a large community-dwelling population of women aged 65 years and over, and to determine whether impaired performances in these tests are associated with falls. DESIGN: One-year prospective study. SETTING: Conducted as part of the Randwick Falls and Fractures Study, in Sydney, Australia. PARTICIPANTS: Four hundred fourteen women aged 65 to 99 years (mean age 73.7 years, SD = 6.3) were randomly selected from the community; 341 of these women were included in the 1-year prospective study. MAIN RESULTS: The prevalence of impairment in all tests increased with age. In the year following assessment, 207 subjects (60.7%) experienced no falls, 63 subjects (18.5%) fell one time only, and 71 subjects (20.8%) fell on two or more occasions. After controlling for age, multiple falling was associated with low contrast visual acuity and contrast sensitivity, poor vibration sense and proprioception, reduced lower limb strength, slow reaction time, and impaired balance, as indicated by four sway tests and two clinical stability measures. Discriminant function analysis identified visual contrast sensitivity, proprioception in the lower limbs, quadriceps strength, reaction time, and sway on a compliant (foam rubber) surface with the eyes open as the variables that significantly discriminated between subjects who experienced multiple falls and subjects who experienced no falls or one fall only (Wilks' lambda = 0.73 (P < 0.001), canonical correlation = 0.52). This procedure correctly classified 75% of subjects into multiple faller or nonmultiple faller groups. CONCLUSIONS: These findings support previous results conducted in retirement village and institutional setting and indicate that the test procedure aids in the identification of older community-dwelling women at risk of falls.

Accidental Falls↗

PubMed1994

Factors associated with falling in elderly hospital patients.

Forty-four patients aged 65 years and over who fell whilst in an acute hospital and 44 patients who did not fall during their hospital stay underwent structured medical examinations to identify factors associated with falling. The control subjects were matched for age (+/- 3 years), sex, patient type, and primary diagnosis. The examination was based on established assessments of posture, balance and gait, the musculoskeletal system, vision, cardiovascular status, and neurological function. Bivariate analyses revealed seven assessment measures that were significantly associated with falls: cognitive impairment, particularly impaired orientation; evidence of previous cerebrovascular accident; incoordination as measured clinically; inability to perform the 'Get-up-and-go' test, especially an inability to turn around after a 5-metre walk, and the use of psycho-active medications. Of these variables, impaired orientation, psycho-active drug use, evidence of stroke, and impaired performance in the 'Get-up-and-go' test were included in a stepwise logistic regression which correctly classified 80% of the patients into faller and non-faller groups. Falling was also related to the number of these identified risk factors. These findings suggest that a simple screening protocol, taking about 5 min to complete, can assist in the identification of patients at risk of falls whilst in hospital.

Accidental Falls↗

PubMed1994

Age-associated differences in sensori-motor function and balance in community dwelling women.

Tests of visual, vestibular, sensori-motor and balance function were administered to 550 women, aged between 20 and 99 years at a Balance and Gait Laboratory. All of the sensory, motor and balance system measures showed significant age-associated differences. Multiple regression analyses revealed that the measures of lower limb sensation were the consistent sensori-motor factors contributing to balance under normal conditions (standing on a firm surface with eyes open or closed). Under more challenging conditions (standing on foam with eyes open) vision, strength and reaction time played significant roles, whilst when standing on foam with eyes closed, vestibular function also made a significant contribution. Analysis of percentage increases in sway under conditions where visual and peripheral sensation systems were removed or diminished, compared with sway under optimal conditions, indicated that up until age 65 there was an increased reliance on vision for balance control. Beyond this age, the contribution made by vision declined, so that in the oldest age-groups reduced vision was less able to supplement peripheral input, resulting in increased sway areas. Peripheral sensation however was the most important sensory system in the maintenance of static postural stability at all ages.

Activities of Daily Living↗

PubMed1994

Predictors of nursing home placement and mortality of residents in intermediate care.

Assessments of sensorimotor function, cognitive status and health measures were made in 95 intermediate-care (hostel) residents (mean age 82.7 years). The residents were then followed up for 3 years to determine which measures were associated with nursing-home placement and/or death. Information on the outcome of 92 participants was available at the end of the 3-year period. At this time, 53 residents (58%) were still residing at the hostel, seven (8%) had been transferred to nursing homes and 32 residents (35%) had died. Sixteen of the 32 subjects who had died had been transferred to nursing homes. Discriminant function analysis identified tactile sensitivity, ankle dorsiflexion strength, reaction time, sway with eyes open on a compliant (foam rubber) surface and cognitive impairment as the variables that significantly discriminated between subjects who were still in intermediate care and subjects who had been transferred to nursing homes. This procedure correctly classified 88% of subjects into intermediate care or nursing home groups. These variables, with the exception of ankle dorsiflexion strength, were also included in the final discriminant model when predicting mortality, correctly classifying 71% of the subjects. The findings indicate that cognitive impairment and reduced functioning in a number of sensorimotor factors are strongly related to poor outcomes for residents in hostel care.

Accidental Falls↗

PubMed1993

Hearing impairment and hearing aid use in women over 65 years of age. Cross-sectional study of women in a large urban community.

OBJECTIVES: (i) To describe the prevalence of self-reported hearing impairment and level of hearing aid use in women aged 65 years and over living in the community; (ii) to provide comparison findings from the National Health Survey and the Survey of Disability and Ageing undertaken by the Australian Bureau of Statistics. DESIGN: Cross-sectional study of a large community population. SETTING: Conducted as part of the Randwick Falls and Fractures Study, in Randwick a surburban area in eastern Sydney. PARTICIPANTS: Four hundred and ninety-six women aged between 65 and 99 years (mean age, 74.6 years) took part in the study. The sample was representative of the population from which it was drawn. RESULTS: We found a higher level of hearing difficulty than the levels reported in the Australian Bureau of Statistics surveys for women of comparative ages, which may reflect differences in the questions posed. The proportions with a hearing aid in the Randwick study and the Survey of Disability and Ageing were very similar (7.1% and 7.3% respectively). Of the one-third of the Randwick sample who reported a hearing difficulty, only half had been referred for audiometry and a quarter had been prescribed an aid. Only slightly more than a third of those who received an aid were regularly wearing it. Among the women with hearing difficulties, not using an aid was not associated with age, cognitive status or subjective health. There was a trend suggesting that those who did not use an aid had increased use of community support services. Women who had not received assistance with their hearing impairment had more difficulty shopping and relied more on family members. CONCLUSION: Almost two-thirds of people prescribed a hearing aid were not wearing it regularly, denying themselves proven benefits in communication, social involvement and life satisfaction. The prescribing of these unused aids represents a huge waste of health resources. A program to increase hearing aid use by hearing impaired people may reduce the waste of health resources and the need for community support services. Such a program may greatly increase the life satisfaction for this very large group of disabled older people.

Aged↗

PubMed1993

Balance, reaction time, and muscle strength in exercising and nonexercising older women: a pilot study.

Twenty-one women, aged 57 to 75 years, who had been taking part in exercise programs for periods of 12 months or more underwent tests of muscle strength, reaction time, proprioception, and body sway. The performance of these women in the tests was compared with 21 women of the same age who were not taking part in any organized physical activity and were not exercising more than 30 minutes a day. The women who had been taking part in the exercise program performed significantly better in the tests of quadriceps strength, reaction time, and sway on a compliant surface than the nonexercising women. The exercisers also had lower body mass index scores. These pilot results suggest that exercise may play a role in improving a number of sensori-motor systems that contribute to stability, and that exercise of this nature may help prevent falls in older women.

Accidental Falls↗

PubMed1993

Hip fractures: changing patterns in hospital bed use in NSW between 1979 and 1990.

Osteoporotic hip fractures are associated with significant medical, social and financial costs. To examine trends in hip fracture incidence, acute hospital admissions, bed use and outcome for these fractures were reviewed for the period 1979-90. In this period, there was a 45% increase in the total number of fractures. In women aged 65 and over increases in admission rate were found between 1979 and 1986. Fracture admission rates for women stabilized after 1986, but remained approximately 7% higher than in the baseline year of 1979. In men aged 65 years and over there was no discernible change in fracture incidence. Length of stay in hospital was inversely related to the total number of proximal femoral fracture cases in each year. As a result of the large decreases in length of stay, overall bed use in 1991 was very similar to that in 1979, in spite of the large increase in fracture admissions. This reduction in length of stay may reflect, not only the pressures of greater demand, but also improved surgical and postoperative management and the effects of early intervention and rapid transit treatments.

Aged↗

PubMed1993

The benefits of exercise in postmenopausal women.

Physical exercise is commonly promoted as a panacea. However many of the claimed benefits, in particular any positive effects on bone density, have not been scientifically proved. We assessed the effects of a twice-weekly aerobic weight-bearing exercise program on bone density in postmenopausal women. We tested bone density at the spine and hip in 19 exercisers with a mean age of 66.4 years (SEM +/- 1.2) before and after a two-year exercise program, and in 11 controls, mean age 65.4 years (SEM +/- 1.5). We also assessed risk factors for cardiovascular disease and tested wellbeing and cognitive function. The mean percentage change in lumbar bone mineral density was -0.8 in exercisers and -3.8 in controls (difference 3.0 per cent; 95 per cent confidence interval (CI) 0.3 to 5.7 per cent; P = 0.031). The mean percentage change in trochanteric bone mineral concentration was +9.6 in exercisers and -4.4 in controls (difference 14.0 per cent; CI 4.6 to 23.5; P = 0.0049). The exercisers also had significantly higher wellbeing and diastolic blood pressure. This study adds strong evidence that twice-weekly weight-bearing aerobic exercise has a protective effect on bone density in postmenopausal women as well as being associated with other measurable benefits.

Aged↗

PubMed1993

An epidemiological study of falls in older community-dwelling women: the Randwick falls and fractures study.

Seven hundred and four women aged between 65 and 99 years (mean age 74.6 years), who were randomly selected from the community, took part in a study to determine whether health and lifestyle factors were associated with falls. In the 12 months before the survey, 66.1 per cent of the subjects experienced no falls, 19.7 per cent fell once and 14.2 per cent fell on two or more occasions. The proportion of women who fell outside the home decreased with age, with a corresponding increase in the proportion who fell inside the home on a level surface. The most common causes of falls reported were trips, slips and loss of balance. Some (27 per cent) suffered injuries as a result of a fall, and the proportion suffering injuries increased with age. Those who rated their health and balance as impaired, those with a limitation in activities of daily living, those receiving community services, those taking psychoactive drugs, and those taking four or more drugs had significantly more falls. On the other hand, those taking part in planned exercise and those active for seven or more hours per week had fewer falls. Smoking and alcohol consumption were not significantly associated with falls. Stepwise logistic regression analysis revealed poor vision, inactivity and subjective fall risk as variables that were independently and significantly associated with falling. These findings highlight possible intervention strategies for reducing falls risk in older people.

Accidental Falls↗

PubMed1993

Clinical parameters associated with falls in an elderly population.

Eighty-one elderly residents of a hostel for the aged (mean age 83.3 years) underwent clinical medical assessments to examine susceptibility to falling. The medical examination was structured and followed a clinical format with particular emphasis upon posture and gait, in addition to routine examination of the cardiovascular, respiratory, neurological, gastrointestinal, haemopoietic, genitourinary, musculoskeletal and visual systems. These subjects were then followed up for 1 year to assess whether these clinical measures were associated with falls. Seventy-six residents were available for follow-up. Thirty-four subjects (44.7%) reported having no falls in the follow-up year, 10 (13.2%) fell once only, 13 (17.1%) fell on two occasions whilst 19 (25.0%) fell three or more times. Seventy-two percent of all falls occurred in the hostel building. Certain clinical factors showed high specificity (i.e. only a few non-fallers screened positive in the tests) but low sensitivity (i.e. there were considerable numbers of residents who screened negatively, but fell in the 12-month follow-up period). Stepwise logistic regression analysis revealed impaired cognition, abnormal reaction to any push or pressure, history of palpitations and abnormal stepping as variables that independently and significantly predicted falling. The equation predicted falls with 70.7% sensitivity and 79.4% specificity, with an overall predictive accuracy of 74.7%. It appears that a modified focussed clinical examination could provide the basis of a short assessment for predicting falls and highlight possible intervention strategies for reducing fall risk.

Accidental Falls↗

PubMed1992

Physiological factors associated with injurious falls in older people living in the community.

Performance in six tests of sensorimotor function was measured in 50 subjects who were admitted to an acute hospital because of a fall (ICD codes E880-888), but who did not suffer a fracture of the lower limbs as a result. Performances in these tests were compared with 50 subjects of the same age and sex who had not fallen in the previous 12 months. It was found that those admitted to hospital because of a fall had decreased tactile sensation, reduced quadriceps strength and increased body sway on firm and compliant surfaces. The fallers also performed poorly in clinical tests of static and dynamic balance. Psychoactive-drug use was associated with falling and a number of test measures, including body sway, static balance, dynamic balance and quadriceps strength. Twenty-seven percent of fallers had poor outcomes, in that 1 year after testing, they had either suffered three or more additional falls, been readmitted to hospital, been transferred to nursing homes or died.

Accidental Falls↗