Showing papers by "Robert G. Cumming published in 1998"

Visual impairment and falls in older adults: the Blue Mountains Eye Study.

Abstract: OBJECTIVES: To examine the association between visual impairment and falls in older people. DESIGN: Cross-sectional survey of eye disease with retrospective collection of falls data. SETTING: Two postcode areas in the Blue Mountains west of Sydney, Australia. PARTICIPANTS: All people 49 years of age and older were invited to participate, 3654 (82.4%) of 4433 eligible residents took part, and 3299 answered questions about falls. MEASUREMENTS: Subjects had a detailed eye examination and answered questions about health and vision status, use of medication, and number of falls in the previous 12 months. RESULTS: Tests of visual function that had a statistically significant association with two or more falls after adjustment for confounders were visual acuity (prevalence ratio (PR) 1.9 for visual acuity worse than 20/30), contrast sensitivity (PR 1.2 for a 1-unit decrease at 6 cycles per degree), and suprathreshold visual field screening (PR 1.5 for 5 or more points missing). However, only visual acuity and contrast sensitivity were significantly associated with two or more falls per 1 standard deviation decrease. The presence of posterior subcapsular cataract (PR 2.1) and use of nonmiotic glaucoma medication (PR 2.0) had a statistically significant association with two or more falls; presence of age-related macular degeneration, diabetic retinopathy, and cortical or nuclear cataract did not. CONCLUSION: Visual impairment is strongly associated with two or more falls in older adults. In addition to poor visual acuity, visual factors such as reduced visual field, impaired contrast sensitivity, and the presence of cataract may explain this association.

Epidemiology of Medication-Related Falls and Fractures in the Elderly

Abstract: About 30% of people aged over 65 years living in the community fall at least once a year; the fall rate is even higher in nursing homes. Many of these falls lead to fractures, the most serious type being hip fractures. Whether or not the use of various medications causes falls and fractures has been the subject of more than 50 observational epidemiological studies, most published after 1988. Few of these studies were specifically designed to investigate the associations between medication use and falls, so most have methodological limitations. Uncontrolled confounding factors are a particular problem. It is important to recognise these flaws in study design when reviewing the scientific literature on the link between medications and falls and fractures. Patients taking psychotropic medications appear to have about a 2-fold increased risk of falls and fractures, compared with individuals not taking these drugs. The strongest evidence is for antidepressants; nearly every relevant study has found an association with falls. The relative effect of selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors and tricyclic antidepressants on falls is still unknown. The effect on the risk of falling of short-acting versus long-acting benzodiazepines is not straightforward: it may be the benzodiazepine dosage that matters, rather than the drug half-life. Whether or not any medications used to treat cardiovascular problems cause falls remains unclear. Current evidence suggests that diuretics, in general, do not cause falls and that thiazide diuretics, in particular, may help prevent fractures by slowing the development of osteoporosis. Some studies have found that use of nonsteroidal anti-inflammatory drugs is associated with falling; this deserves further study. Reducing the use of psychotropic drugs by residents of nursing homes should be a high priority for physicians, pharmacists and nursing staff. Psychotropic drug use should also be kept to a minimum among older people living in the community.

Cohort study of vitamin C intake and cognitive impairment

Abstract: To test the hypothesis that vitamin C protects against cognitive impairment, the authors conducted a cohort study (n=117) in a retirement community in Sydney, Australia. Vitamin C intake was assessed at baseline (1991) with a semiquantitative food frequency questionnaire, and cognitive function was assessed 4 years later (1995). After adjustment for age, sex, smoking, education, total energy intake, and use of psychotropic medications, consumption of vitamin C supplements was associated with a lower prevalence of more severe cognitive impairment (based on scores on the Mini-Mental State Examination; adjusted odds ratio=0.39, 95% confidence interval 0.18-0.84). There were no associations between vitamin C intake and scores on tests of verbal and category fluency. This study suggests that vitamin C might protect against cognitive impairment.

Bilateral involvement by age related maculopathy lesions in a population

Abstract: AIMS—To describe the influences of age and sex on the frequency of bilateral age related macular degeneration (AMD) and age related maculopathy (ARM) lesions. METHODS—The Blue Mountains Eye Study examined 3654 older Australians, 82% of permanent residents living in an area west of Sydney. Stereo macular photographs were graded for AMD (neovascular maculopathy and geographic atrophy) and early ARM lesions (soft drusen, reticular drusen, hyperpigmentation, and hypopigmentation). RESULTS—Among 230 gradable cases of AMD or early ARM, 183 (80%) were bilateral. For AMD, 39/69 cases (57%) were bilateral, while for early ARM, 123/161 cases (77%) had signs in both eyes. Of the individual lesions, reticular drusen (91%) and indistinct soft drusen (79%) were most frequently present in both eyes. Geographic atrophy was bilateral in 56%, neovascular AMD in 40%, and distinct soft drusen in 47%, while hyperpigmentation was bilateral in 38% and hypopigmentation in only 28% of cases. A consistent age related increase in bilateral distribution was observed for most lesions. After adjusting for effects of age, current smoking, and AMD family history AMD and ARM component lesions, except for soft drusen, were more frequently bilateral in women. This sex difference was significant only for neovascular AMD, odds ratio 7.7 (95% confidence intervals 1.3-46.7). An AMD family history was more frequently reported in cases with bilateral involvement. CONCLUSIONS—This study has documented differences in the age related bilaterality of individual ARM components with higher bilateral rates for reticular or indistinct soft drusen compared with other lesions. The increased bilaterality of most ARM lesions among women is likely to contribute to the increased age adjusted risk of AMD blindness found in women. Keywords: age related maculopathy; age related macular degeneration; drusen

Prevalence and vascular associations with migraine in older Australians.

Abstract: Background: Migraine is a common disorder with recently described vascular associations, yet there are few Australian population-based data describing migraine prevalence. Aims: To assess the prevalence and vascular associations with lifetime past history of typical migraine headache in a representative sample of older Australians. Methods: The Blue Mountains Eye Study examined 3654 permanent residents aged 49 or older living in two postcode areas, west of Sydney (82.4% participation) during 1992-4. A structured interview was administered, including questions about past or present history of typical migraine. The diagnosis was consistent with International Headache Society criteria. Results: A lifetime past history of typical migraine was given by 17% of participants, including 22% of women and 10% of men, a female:male ratio of 2.3:1. A marked trend for declining lifetime migraine frequency with increasing age was found for both sexes. Modest statistically significant associations were found with vascular disease history, after multivariate adjustment, which included vascular risk factors. These associations were stronger in men than in women. Among men, typical migraine was significantly associated with history of angina, odds ratio (OR) 2.0, acute myocardial infarction (OR 1.9) and stroke (OR 2.2). Among women, statistically significant associations were present only with history of myocardial infarct (OR 1.8). Conclusions: These data indicate similar prevalence rates for lifetime typical migraine history in a representative sample of older Australians, compared to recent US and Canadian populations. Modest, statistically significant associations between typical migraine and past history of vascular disease were found, with the strongest associations found in men.