Search PubMed⌕ Search

Biomedical subjects

R Bonita

Publications and source records attributed to R Bonita.

At least 37 records · Page 2Linked to original sources
PubMed1997

Prevalence of stroke and stroke-related disability. Estimates from the Auckland stroke studies.

BACKGROUND AND PURPOSE: To provide estimates of the prevalence of stroke and stroke-related disability for international comparisons and for planning purposes. METHODS: Estimates of prevalence were derived from two population-based studies conducted 10 years apart in Auckland, New Zealand. The first, carried out in 1981, included information on survival and stroke-related disability to 14 years after stroke, and the second, undertaken in 1991 to 1992, included this information up to 3 years after stroke. An actuarial model was developed that took into account changes in incidence, long-term survival, and population structure. RESULTS: Overall, it was estimated that 7491 people (3793 men and 3698 women) living in Auckland (total population 945,000) in 1991 had experienced a stroke at some stage in the past. This represents an age-standardized rate of 833 per 100,000 (991 per 100,000 in men and 706 per 100,000 in women) in the population aged 15 years and older. When only those who have made an incomplete recovery are considered, prevalence falls to 461 per 100,000. Of this group, one third (173 per 100,000 population 15 years and older) required assistance in at least one self-care activity. CONCLUSIONS: Usual estimates of stroke prevalence, which include all people who have ever experienced a stroke, may overestimate by almost twofold the prevalence of stroke-related disability, since many have either recovered or have no continuing dependency related to stroke. Overall prevalence does not provide information with sufficient precision for planning and purchasing ongoing services for stroke patients.

Activities of Daily Living↗
PubMed1997

Ethnic differences in stroke incidence and case fatality in Auckland, New Zealand.

BACKGROUND AND PURPOSE: This study compares stroke incidence, 28-day case fatality, and hospital management for Maori, Pacific Islands people ("Pacific people"), and others (mostly Europeans) living in Auckland, New Zealand. METHODS: Data come from the Auckland Stroke Study, a population-based study that registered all stroke events occurring among Auckland residents aged 15 years or more during a 1-year period ending February 29, 1992. RESULTS: During the study year, 1803 stroke events were registered, including 82 (4.5%) in Maori, 113 (6.3%) in Pacific people, 1572 (87.2%) in Europeans, and 36 (2.0%) in others of Indian or Chinese origin. The mean +/- SD age of stroke patients was 55.0 +/- 16.0 years in Maori, 59.7 +/- 14.9 years in Pacific people, and 73.3 +/- 12.1 years in Europeans. Maori and Pacific people have significantly higher estimated relative risks of stroke compared with Europeans (OR, 1.34; 95% confidence interval [CI], 1.05 to 1.67 in Maori; and OR, 1.63; 95% CI, 1.33 to 1.98 in Pacific people). Maori and Pacific people also have higher estimated relative risks of death within 28 days of stroke compared with Europeans, especially men. CONCLUSIONS: This study indicates that there are important differences in stroke incidence rates and case fatality among the major ethnic groups in Auckland. The reasons for the higher incidence rates in Maori and Pacific people may be related to levels of risk factors, but this requires further investigation. Ongoing monitoring of stroke incidence and outcome should include separate reporting by ethnicity.

Adolescent↗
PubMed1996

Faecal examination of Fasciola eggs fixed with formalin solution using the beads technique.

Faecal examination for Fasciola eggs which were preserved in 5% and 10% formalin and TAF solutions for 6 years was carried out using the Beads technique. The morphological characters and the distinctive yellowish color of Fasciola eggs were retained and appeared similar to those of fresh eggs. The mean egg recovery rate of eggs in TAF solution was significantly lower than the others (P < 0.01). The egg recovery rates from 5% and 10% formalin samples were 57.2% and 60.8%, respectively, and these values were similar to the value of 58.8% for fresh Fasciola eggs in cattle faeces. For Paramphistomum eggs, preserved with 5% formalin, the mean egg recovery rate was 64.7%. Fasciola eggs and Paramphistomum eggs were easily identified by their morphological characters in this experiment. The present data demonstrated that preservation with 5% formalin solution is an acceptable means of storing faecal samples for later examination of Fasciola and Paramphistomum eggs using the Beads technique and presumably by other fluke sedimentation methods.

Animals↗
PubMed1996

Older women in an aging world: achieving health across the life course.

This article, based on a report (Women, aging and health: achieving health across the life span) prepared for the WHO Global Commission on Women's Health under the guidance of WHO's Aging and Health Programme, presents demographic data that clearly demonstrate the need for recognition of the health of aging women as a global issue of major public health concern. The authors show that, while female life expectancy at birth is significantly different in developed and developing countries (because of high infant and maternal mortality in the latter), these differences tend to decrease for women in developing countries who reach middle age. The authors review the various facets of the "gender transition" brought about by demographic and epidemiological transitions, drawing attention to contrasts between the situation in developing countries in Asia and Latin America and that in Eastern Europe, for example. The role of older women as care-givers is discussed, as is the likelihood of a future increase in the proportion of older women living alone in the developing world (a factor which renders them particularly vulnerable in many socioeconomic and health respects). Suggestions are made on methodologies for monitoring health trends in aging women, and on the role of WHO in this respect. A basic goal for global strategies relating to the health of older women is formulated: reduction of the inequities in life expectancy between developed and developing countries.

Adolescent↗
PubMed1995

Geographical variations in the organisation of general practice.

AIMS: To describe organisational characteristics of New Zealand general practice and to investigate inter-regional variations in these characteristics. METHODS: Data were collected by standardised questionnaires from general practitioners in Auckland, Waikato and Taranaki. The Waikato data were collected in July-August 1991 by postal survey, the Taranaki data were collected May-June 1992 by postal survey and the Auckland data were collected December 1990 to January 1991 by face-to-face interview. RESULTS: The response rates were Auckland 98% (167/171), Waikato 84% (185/220) and Taranaki 79% (79/100). There were significantly more overseas trained graduates in rural areas than in urban areas. Average practice size was 2.3 full time equivalent doctors, with each 100 doctors employing 71 nurses and 77 receptionists. The number of patients seen per week ranged from 109-141. Almost all (95%) general practitioners operated appointment systems. One in five general practitioners had patients in private hospitals, and more than half (58%) had patients in rest homes. At the time of interview, 29% of Auckland general practitioners used computers in their practices compared with over 50% in Waikato and Taranaki (p < 0.05). A smaller proportion of Auckland general practitioners had access to age/sex registers and fewer Auckland general practitioners had a recall system. Of Auckland general practitioners with recall systems, a greater proportion used them for mammograms, blood pressure and lipid measurements compared with elsewhere. CONCLUSIONS: There are some significant regional variations in the functional characteristics of general practice in New Zealand which should be taken into account when planning primary care services in different regions. Should budget holding and managed care be introduced, computerised practices will be required. This will have significant resource implications.

Adult↗
PubMed1995

Approaches to the problems of measuring the incidence of stroke: the Auckland Stroke Study, 1991-1992.

BACKGROUND: Stroke registers are the preferred choice for determining incidence, case-fatality and severity of acute stroke in defined populations. This paper highlights some of the problems likely to be encountered in this endeavour by describing the experience of measuring acute stroke prospectively. METHODS: The Auckland Stroke Study is a community-based study among 945,000 residents of the Auckland region, New Zealand. Standard definitions and overlapping case-finding methods were used to identify all new acute stroke events occurring during the 12-month period ending 1 March 1992. Particular attention was directed at including non-fatal strokes managed outside hospital. The latter were identified by use of a cluster sample, a technique suitable for populations where residents have a personal primary health care physician. RESULTS: The comprehensive sources of referral to the study involved the review of 5736 records, less than one-third of which met the criteria for inclusion. The majority of included acute stroke events (n = 1803) were found through routinely available sources such as hospital admission records (63%) and death registrations (10%). The remainder (27%) were identified through intensive efforts at case-finding of stroke events managed outside hospital. The 1803 events were registered in 1761 people, 817 men and 944 women; for 587 (72%) men and 718 (76%) women, the stroke was the first ever experienced. CONCLUSIONS: While time-consuming, costly and demanding, there appears to be no easier alternative to a register to estimate incidence. This study demonstrates the importance of the use of comprehensive case-finding sources and suggests approaches to overcoming the difficulties in monitoring stroke incidence in large populations.

Adolescent↗
PubMed1995

Multinational comparisons of stroke epidemiology. Evaluation of case ascertainment in the WHO MONICA Stroke Study. World Health Organization Monitoring Trends and Determinants in Cardiovascular Disease.

BACKGROUND AND PURPOSE: As part of the WHO MONICA Project (World Health Organization Monitoring Trends and Determinants in Cardiovascular Disease), mortality and incidence rates of acute stroke in 14 centers covering 21 populations from 11 countries were compared. METHODS: In this report, coverage and quality of the MONICA stroke registers were evaluated on five key indicators using data submitted to the MONICA Data Center. RESULTS: A low ratio of MONICA stroke register to routine statistics of stroke mortality and a low proportion of nonfatal out-of-hospital events were the most common biases; they indicate that identifications of fatal cases and/or case finding of nonfatal events occurring outside the hospital were inadequate in many MONICA centers. In 10 populations, the data quality analyses suggested that clarification of possible biases would be needed before these populations can be included in a comparative study. Data from the remaining 11 populations meet the data quality standards for multinational comparisons with respect to case ascertainment. CONCLUSIONS: These results show that multinational comparisons of stroke incidence involve considerable problems in developing and maintaining appropriate standards of data quality. However, after considerable efforts to ensure quality, comparisons of stroke data within the MONICA Project are possible among a large number of the MONICA populations. Our observations also indicate that results from multinational comparisons of stroke mortality based on routine statistics must be interpreted with caution.

Acute Disease↗
PubMed1995

Inadequacy of clinical scoring systems to differentiate stroke subtypes in population-based studies.

BACKGROUND AND PURPOSE: We undertook to examine the usefulness for epidemiological studies of two well-known validated clinical scoring methods, the Guys' Hospital Stroke score and the Siriraj Hospital Stroke score, to classify strokes into the two main types, hemorrhagic and ischemic, in epidemiological studies. METHODS: Patients from a population-based stroke register who received either a CT scan or an autopsy were retrospectively scored using the two clinical scoring methods. The scores were then compared with the CT scan and autopsy results to determine the sensitivity, specificity, and positive predictive value for intracranial hemorrhage (primary intracerebral and subarachnoid hemorrhage) and ischemic stroke. RESULTS: Over a 12-month period, 554 patients from a population-based study underwent CT scanning. Films or autopsy reports were available for 521 patients, and of these, sufficient clinical information to calculate the Guys' Hospital Stroke score and the Siriraj Hospital Stroke score was available for 464 and 475 patients, respectively. For the Guys' Hospital Stroke score, the sensitivity and specificity for intracranial hemorrhage were 31% and 95%, respectively; the positive predictive value was 73%. The sensitivity and specificity for ischemic stroke were 78% and 70%, respectively, and the positive predictive value was 86%. For the Siriraj Hospital Stroke score, the sensitivity and the specificity for intracranial hemorrhage were 48% and 85%, respectively; the positive predictive value was 59%. The sensitivity and specificity for ischemic stroke were 61% and 74%, respectively, and the positive predictive value was 84%. CONCLUSIONS: This validation study suggests that both clinical scores lack sufficient validity to be used in epidemiological studies for classification of stroke types and should probably not be used in the randomization of patients into treatment trials using thrombolytic or antithrombotic drugs in the absence of diagnostic information based on neuroimaging techniques.

Adult↗
PubMed1994

The worldwide problem of stroke.

Cardiovascular disease is the leading cause of death worldwide with almost one third of all cardiovascular deaths ascribed to stroke. In contrast to coronary heart disease, most of the strokes occur in developing countries; China alone has about 1 million deaths from stroke each year. From a global perspective the stroke situation is changing rapidly, and considerable progress has been made in documenting the changes in stroke mortality. Despite the favorable trends in stroke mortality in many countries, stroke will become an increasingly important health problem as the world's population continues to age.

Aged↗
PubMed1994

Stroke incidence and case fatality in Australasia. A comparison of the Auckland and Perth population-based stroke registers.

BACKGROUND AND PURPOSE: Population-based studies are crucial for identifying explanations for the decline in mortality from stroke and for generating strategies for public health policy. However, the present particular methodological difficulties, and comparability between them is generally poor. In this article we compare the incidence and case fatality of stroke as assessed by two independent well-designed incidence studies. METHODS: Two registers of acute cerebrovascular events were compiled in the geographically defined metropolitan areas of Auckland, New Zealand (population 945,369), during 1991-1992 for 12 months and Perth, Australia (population 138,708), during 1989-1990 for 18 months. The protocols for each register included prospective ascertainment of cases using multiple overlapping sources and the application of standardized definitions and criteria for stroke and case fatality. RESULTS: In Auckland, 1803 events occurred in 1761 residents, 73% of which were first-ever strokes. The corresponding figures for Perth were 536 events in 492 residents, 69% of which were first-ever strokes. Both studies identified a substantial proportion of nonfatal strokes managed solely outside the hospital system: 28% in Auckland and 22% in Perth of all patients registered. The age-standardized annual incidence of stroke (all events) was 27% higher among men in Perth compared with Auckland (odds ratio, 1.27; P = .016); women tended to have higher rates in Auckland, although these differences were not statistically significant. In both centers approximately a quarter of all patients died within the first month after a stroke. There were significant differences in the prevalence of hypertension among first-ever strokes. CONCLUSIONS: These two studies emphasize the importance of identifying all patients with stroke, both hospitalized and nonhospitalized, in order to measure the incidence of stroke accurately. The incidence and case fatality of stroke were remarkably similar in Auckland and Perth in the early 1990s. However, there are differences in the sex-specific rates that correspond to differences in the pattern of risk factors.

Adolescent↗
PubMed1993

Changes in stroke incidence and case-fatality in Auckland, New Zealand, 1981-91.

The explanation for the substantial decline in stroke death rates can be investigated only by measuring trends in stroke incidence and case-fatality. Two community-based studies carried out in Auckland, New Zealand, in 1981 and 1991 used comparable methods and definitions, met criteria for well-designed studies, and had the power to detect small changes in incidence and case-fatality rates. 703 events (representing 50% of all strokes) were registered in 1981 and 1735 events in 1991. 521 (74.1%) and 1255 (72.3%) events in 1981 and 1991, respectively, were first-ever (in a lifetime) strokes. Although there was no change in overall stroke incidence between 1981 and 1991, there were changes in age and sex groups. The incidence rate among women younger than 75 years rose by a fifth (rate ratio 1.23 [95% CI 1.04-1.47]), whereas that in men of 75 years and older fell by a third (rate ratio 0.67 [0.54-0.82]). The 28-day case-fatality declined from 27.1 (21.7-32.6)% to 21.9 (18.1-25.7)% in men and from 37.6 (31.8-43.5)% to 25.8 (22.3-29.4)% in women from 1981 to 1991, but the decline was not statistically significant in any age or sex group. These findings suggest that we need to reappraise strategies for the prevention of stroke and assess the implications of improved survival in elderly stroke patients.

Adolescent↗