Lower respiratory tract symptoms in Queensland schoolchildren: risk factors for wheeze, cough and diminished ventilatory function.

BACKGROUND--The occurrence of respiratory symptoms and abnormal lung function in children is known to be influenced by genetic and many environmental factors. The association between specific respiratory symptoms in children of school age and their parents has been examined. METHODS--Respiratory symptoms and ventilatory function were recorded for 4549 schoolchildren in Queensland, Australia. RESULTS--The cumulative prevalence of wheezing was 23.1% of 8 year olds and 20.8% of 12 year olds, and the prevalence of wheezing within the previous 12 months was 13.9% and 10.5% respectively. A parental history of asthma or wheeze and hayfever was associated with wheeze in the child, but did not affect either the age of onset or frequency of episodes. A history of frequent cough in children who had never wheezed was associated with a parental history of frequent bronchitis, but less strongly with parental wheeze. These familial aggregations were not mediated by common exposure to cigarette smoke. Both a history of parental wheeze and maternal cigarette use were associated with a decrease in FEF25-75 in the child and these effects were additive. CONCLUSIONS--The association of specific symptoms (wheeze and cough without wheeze) in parent and offspring is interpreted as evidence for different mechanisms of familial transmission, which may be genetic.     

Descriptive study of cough, wheeze and school absence in childhood.

BACKGROUND: Respiratory symptoms such as cough and wheeze are associated with significant morbidity, including school absenteeism. METHODS: A respiratory questionnaire was sent to the parents of all 5727 children aged 7-9 years of age registered with 95 general practitioners in the Southampton area to determine (a) the prevalence of asthma, cough and wheeze, (b) the effects of respiratory symptoms on school absenteeism, and (c) the use of anti-asthma medication. RESULTS: A total of 4830 parents replied (response rate 86%). The 12 month prevalence of wheeze in the absence of cough was 5.5%, cough in the absence of wheeze was 10.0%, and 7.6% reported cough and wheeze; 15.2% of children had been diagnosed. Of the 4830 who replied, 12.7% were receiving bronchodilators, 0.6% xanthine derivatives, 1.7% sodium cromoglycate, and 4.1% inhaled corticosteroids. In all, 348 (7.2%) children had missed more than five days of schooling in the preceding year for respiratory symptoms, while 43 children (0.9%) had missed more than 20 days of schooling in the preceding year. Of the children who had missed more than five days of schooling, 43% reported cough and wheeze, 33% cough alone, and 16% wheeze alone in the preceding year. Compared with children who coughed, those who wheezed were significantly more likely to be diagnosed as asthmatic and to be receiving bronchodilators or inhaled corticosteroids. CONCLUSIONS: In this study, cough was the most frequently reported symptom amongst children missing more than five days of schooling per year.     

A community survey of respiratory disease among East Indian and African adults in Guyana

The belief that chronic bronchitis is more prevalent among Indians than Africans in the Caribbean area was investigated by a community survey in Guyana. Respiratory symptoms were assessed by a standard questionnaire, ventilatory capacities were measured, and chest radiographs were taken of some 800 African and Indian men and women aged 35 to 54 years living in adjacent and similar communities. Histories of morning cough, chronic cough, morning phlegm, and chronic phlegm (chronic bronchitis) were more common in Indians than Africans. Although these respiratory symptoms were much more common in smokers than non-smokers, the higher prevalence rates in Indians could not be explained by smoking habits which were similar in the two races. Chronic bronchitis occurred in 17·3% of Indian and 2·4% of African male smokers and in 16·1% and 2·2% of Indian and African female non-smokers respectively. Judging by the history, lung function, and clinical signs, chronic bronchitis was more severe in Indians than Africans. The condition was more common among field labourers on sugar estates but, although the majority of field labourers were Indian, this occupational difference only partially explained the difference in prevalence between Indians and Africans. Indians, for reasons unknown, appear to have a greater susceptibility than Africans to chronic bronchitis.     

Ethnic variation in respiratory morbidity and lung function in childhood.

In a population of 5689 primary schoolchildren there were few important differences between children of European (n = 5287), African (n = 198), and Indian origin (n = 204) in the prevalence of a history of past respiratory illnesses or current respiratory symptoms. The reported 12 month period prevalence of the symptom "ever wheezy" was 15%, 18%, and 17% respectively in the three ethnic groups (differences not significant). In a subsample of 973 European, 47 African, and 40 Indian children forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were significantly lower by 12% and 13% in Africans and by 8% and 9% in Indians than in Europeans after adjustment to the group mean height of 128 cm. No significant ethnic variation was found for forced mid expiratory flow, FEV1/FVC, or mean transit time. Since the lung function studies were performed on a sample from a large population with little variation in respiratory morbidity, the differences are likely to reflect human biological differences. Separate prediction equations need to be developed for the different ethnic groups in childhood.     

Comparison of the prevalence of asthma among Asian and European children in Southampton.

BACKGROUND: Primary health care workers have reported an impression that asthma is commoner among Asian than European children, and a cross sectional survey was designed to compare the prevalence in Asian and European children. METHODS: The survey was carried out in children aged 7-11 in eight primary schools in Southampton. Four schools contained predominantly children of European ancestry, two contained predominantly Asian children, and two contained a mixture of ethnic groups. Data were collected by means of parent completed questionnaire on recent asthma symptoms, diagnosis, morbidity, and treatment from 759 European and 274 Asian children. RESULTS: The prevalence of reported wheeze in the previous 12 months was higher among European (19.6%) than Asian children (11.9%), as was the prevalence of a night cough (European 64.2%, Asian 42.3%). Although the prevalence of diagnosed asthma was higher in European (12%) than Asian (6.2%) children, a slightly higher proportion of Asian than European children with current wheeze had visited their doctor (European 66.9%, Asian 78.1%, not significant) or been admitted to hospital for wheezing (European 4.8%, Asian 6.5%) in the previous 12 months. CONCLUSIONS: This study failed to demonstrate a higher prevalence of asthma among Asian than European children in Southampton.     

Locally generated particulate pollution and respiratory symptoms in young children

BACKGROUND: Particulate matter <10 mum (PM(10)) from fossil fuel combustion is associated with an increased prevalence of respiratory symptoms in children and adolescents. However, the effect of PM(10) on respiratory symptoms in young children is unclear. METHODS: The association between primary PM(10) (particles directly emitted from local sources) and the prevalence and incidence of respiratory symptoms was studied in a random sample cohort of 4400 Leicestershire children aged 1-5 years surveyed in 1998 and again in 2001. Annual exposure to primary PM(10) was calculated for the home address using the Airviro dispersion model and adjusted odds ratios (ORS) and 95% confidence intervals were calculated for each microg/m(3) increase. RESULTS: Exposure to primary PM(10) was associated with the prevalence of cough without a cold in both 1998 and 2001, with adjusted ORs of 1.21 (1.07 to 1.38) and 1.56 (1.32 to 1.84) respectively. For night time cough the ORs were 1.06 (0.94 to 1.19) and 1.25 (1.06 to 1.47), and for current wheeze 0.99 (0.88 to 1.12) and 1.28 (1.04 to 1.58), respectively. There was also an association between primary PM(10) and new onset symptoms. The ORs for incident symptoms were 1.62 (1.31 to 2.00) for cough without a cold and 1.42 (1.02 to 1.97) for wheeze. CONCLUSION: In young children there was a consistent association between locally generated primary PM(10) and the prevalence and incidence of cough without a cold and the incidence of wheeze which was independent of potential confounders.     

High prevalence of NIDDM and impaired glucose tolerance in Indian, Creole, and Chinese Mauritians. Mauritius Noncommunicable Disease Study Group

Mauritius, a multiethnic island nation in the southwestern Indian Ocean, has one of the world's highest diabetes mortality rates. The prevalence of both impaired glucose tolerance (IGT) and non-insulin-dependent diabetes mellitus (NIDDM) was investigated in 5080 Muslim and Hindu Indian, Creole (mixed African, European, and Indian origin), and Chinese Mauritian adults aged 25-74 yr who were selected by random cluster sampling. Based on a 75-g oral glucose tolerance test and World Health Organization criteria, the age-standardized prevalence of IGT was significantly greater in women (19.7%, 95% confidence interval [CI] 18.1-21.2) than in men (11.7%, CI 10.5-12.8). By contrast, the prevalence of NIDDM was similar in men (12.1%, CI 10.9-13.4) and women (11.7%, CI 10.5-12.8) for all ethnic groups combined. The sex difference in IGT prevalence was seen in all ethnic groups, but for NIDDM, the sex difference was not consistent across ethnic groups. However, age- and sex-standardized prevalence of IGT and NIDDM was remarkably similar across ethnic groups (16.2 and 12.4% in Hindu Indians, 15.3 and 13.3% in Muslim Indians, 17.5 and 10.4% in Creoles, and 16.6 and 11.9% in Chinese, respectively). Three new cases of diabetes were diagnosed for every two known cases. The high prevalence of abnormal glucose tolerance in Indian subjects is consistent with studies of other migrant Indian communities, but the findings in Creole and, in particular, Chinese subjects are unexpected. Potent environmental factors shared between ethnic groups in Mauritius may be responsible for the epidemic of glucose intolerance.     

Trends in the prevalence of respiratory symptoms and treatment in Dutch children over a 12 year period: results of the fourth consecutive survey

BACKGROUND: Although there is considerable evidence that the prevalence of childhood asthma has increased over the last decades, it is not clear if this trend is still ongoing. A study was undertaken to investigate whether previously observed trends in the prevalence of respiratory symptoms, physician visits, medication use, and absence from school in Dutch children aged 8-9 years persisted in 2001. METHODS: Parents of 1154 children aged 8-9 years eligible for a routine physical examination in 2001 were asked to complete a questionnaire on the respiratory health of their child. RESULTS: In 2001, 1102 children (95.5%) participated in the survey. Similarly high response rates were obtained in the surveys of 1989, 1993 and 1997, with 1794, 1526 and 1670 children aged 8-9 years participating in the respective surveys. The decreasing trend previously observed for recent wheeze between 1989 and 1997 persisted into 2001, particularly in boys. After increasing between 1989 and 1997, the prevalence of shortness of breath with wheeze decreased between 1997 and 2001. The proportion of wheezy children using medication increased between 1989 and 2001 in boys (42.9% v 64.8%; p = 0.003), but the increase was not statistically significant in girls (34.0% v 45.7%; p = 0.096). CONCLUSION: The prevalence of recent wheeze in Dutch school children has declined steadily since 1989. The rising prevalence of medication use in symptomatic children over time may reflect better asthma control and may partly explain the concurrently decreasing trend in the prevalence of asthma symptoms in our study population.     

Prevalence of asthma and risk factors among Chinese, Malay, and Indian adults in Singapore.

BACKGROUND--The prevalence and morbidity of asthma vary greatly among different ethnic communities and geographical locations, but the roles of environmental and genetic factors are not fully understood. The differences in prevalence of adult asthma among Chinese, Malay, and Indian ethnic groups in Singapore were examined, and the extent to which these could be explained by personal and environmental factors were investigated. METHODS--A stratified disproportionate random sample (n = 2868) of Chinese (n = 1018), Malays (n = 967), and Indians (n = 883) of both sexes was drawn from households in five public housing estates, and an interviewer administered questionnaire was used to determine cumulative and current prevalence of "physician diagnosed asthma" (symptoms with a physician diagnosis of asthma). RESULTS--Lifetime cumulative prevalence (standardised to the general population) of "physician diagnosed asthma" was 4.7% in men and 4.3% in women; 12 month period prevalences were 2.4% and 2.0%, respectively. Cumulative prevalence of asthma was significantly higher in Indians (6.6%) and Malays (6.0%) than in Chinese (3.0%); period prevalences of asthma were 4.5% in Indians, 3.3% in Malays, and 0.9% in Chinese. Ownership of cats or dogs was more frequent in Malays (15.4%) and Indians (11.2%) than in Chinese (8.8%). Rugs and carpets were also more frequently used by Malays (52.2%) and Indians (40.7%) than by Chinese (8.9%). Current smoking prevalences were higher in Malays (27.3%) than in Indians (19.4%) and Chinese (23.0%). Malays and Indians did not have higher rates of atopy (11.1% and 15.2%, respectively) than Chinese (15.4%). Adjustment for these factors in multivariate analyses reduced the greater odds of asthma in Malays and Indians, but not to a significant extent. CONCLUSIONS--There are ethnic differences in the prevalence of asthma in Singapore which are not entirely explained by differences in smoking, atopy, or other risk factors. Other unmeasured environmental factors or genetic influences are likely to account for residual differences in the prevalence of asthma.     

Asthma in preschool children: prevalence and risk factors

BACKGROUND: The prevalence of asthma in children has increased in many countries over recent years. To plan effective interventions to reverse this trend we need a better understanding of the risk factors for asthma in early life. This study was undertaken to measure the prevalence of, and risk factors for, asthma in preschool children. METHODS: Parents of children aged 3-5 years living in two cities (Lismore, n=383; Wagga Wagga, n=591) in New South Wales, Australia were surveyed by questionnaire to ascertain the presence of asthma and various proposed risk factors for asthma in their children. Recent asthma was defined as ever having been diagnosed with asthma and having cough or wheeze in the last 12 months and having used an asthma medication in the last 12 months. Atopy was measured by skin prick tests to six common allergens. RESULTS: The prevalence of recent asthma was 22% in Lismore and 18% in Wagga Wagga. Factors which increased the risk of recent asthma were: atopy (odds ratio (OR) 2.35, 95% CI 1.49 to 3.72), having a parent with a history of asthma (OR 2.05, 95% CI 1.34 to 3.16), having had a serious respiratory infection in the first 2 years of life (OR 1.93, 95% CI 1.25 to 2.99), and a high dietary intake of polyunsaturated fats (OR 2.03, 95% CI 1.15 to 3.60). Breast feeding (OR 0.41, 95% CI 0.22 to 0.74) and having three or more older siblings (OR 0.16, 95% CI 0.04 to 0.71) decreased the risk of recent asthma. CONCLUSIONS: Of the factors tested, those that have the greatest potential to be modified to reduce the risk of asthma are breast feeding and consumption of polyunsaturated fats.     

Trends in the prevalence of asthma in Scottish and English primary school children 1982-92.

BACKGROUND--Some doubts exist as to whether the increase in the prevalence of asthma is real or an artefact. The 10 year trend of asthma up to 1993 in England and Scotland was therefore assessed. METHODS--Information on asthma and bronchitis attacks, occasional wheeze, and persistent wheeze in the last 12 months, was obtained using a self administered questionnaire completed by the parents. Exactly the same questions were asked in 14 study areas in Scotland and 22 study areas in England in 1982 or 1983 and in 1992 or 1993 in 5-11 year old children. RESULTS--The numbers of children with data for all respiratory illness were 5556 (85.2%) and 5801 (87.1%) in England and 3748 (90.4%) and 3738 (90.4%) in Scotland in 1982 and 1992, respectively. There was a significant increase in asthma attacks (approximately three times more in 1992 than in 1982) and occasional wheeze (30-60% more in 1992 than in 1982) in both sexes in England and Scotland. Persistent wheeze also increased in both countries, but the increase was significant only in England (30-40% more in 1992 than in 1982). CONCLUSIONS--The study coincides with others that suggest that the increased prevalence of asthma may be due, in part, to changes in diagnostic behaviour. However, the continuing increase of persistent wheeze in the total sample suggests that part of the increase is real. There was no difference in the increase of persistent wheeze between Scotland and England, but the trend was only significant in England.     

Increasing prevalence of asthma diagnosis and symptoms in children is confined to mild symptoms

BACKGROUND: The prevalence of childhood asthma is increasing but few studies have investigated trends in asthma severity. We investigated trends in asthma diagnosis and symptom morbidity between an eight year time period in a paired prevalence study. METHODS: All children in one single school year aged 8-9 years in the city of Sheffield were given a parent respondent questionnaire in 1991 and 1999 based on questions from the International Survey of Asthma and Allergy in Children (ISAAC). Data were obtained regarding the prevalence of asthma and wheeze and current (12 month) prevalences of wheeze attacks, speech limiting wheeze, nocturnal cough and wheeze, and exertional symptoms. RESULTS: The response rates in 1991 and 1999 were 4580/5321 (85.3%) and 5011/6021 (83.2%), respectively. There were significant increases between the two surveys in the prevalence of asthma ever (19.9% v 29.7%, mean difference 11.9%, 95% confidence interval (CI) 10.16 to 13.57, p<0.001), current asthma (10.3% v 13.0%, mean difference 2.7%, 95% CI 1.44 to 4.03, p<0.001), wheeze ever (30.3% v 35.8%, mean difference 5.7%, 95% CI 3.76 to 7.56, p<0.001), wheeze in the previous 12 months (17.0% v 19.4%, mean difference 2.5, 95% CI 0.95 to 4.07, p<0.01), and reporting of medication use (16.9% v 20%, mean difference 3.0%, 95% CI 1.46 to 4.62, p<0.001). There were also significant increases in reported hayfever and eczema diagnoses. CONCLUSIONS: Diagnostic labelling of asthma and lifetime prevalence of wheeze has increased. The current 12 month point prevalence of wheeze has increased but this is confined to occasional symptoms. The increased medication rate may be responsible for the static prevalence of severe asthma symptoms. The significant proportion of children receiving medication but reporting no asthma symptoms identified from our 1999 survey suggests that some children are being inappropriately treated or overtreated.     

Childhood asthma in South London: trends in prevalence and use of medical services 1991-2002

BACKGROUND: Hospital admission rates for asthma in Britain rose during the 1980s and fell during the 1990s, but less is known about recent trends in the prevalence of asthma. METHODS: In 1991 and 2002 the same questionnaire was distributed to parents of all school pupils in year 3 (aged 7-8 years) in the London borough of Croydon. Parents of currently wheezy children were then invited for home interview (100% targeted in 1991, 66% in 2002). RESULTS: The prevalence of wheeze during the previous year increased from 12.9% in 1991 to 17.8% in 2002 (prevalence ratio 1.39 (95% CI 1.23 to 1.56)). Increases were observed in frequent (1.54 (95% CI 1.16 to 2.03)) and infrequent attacks, severe speech limiting episodes (2.25 (95% CI 1.34 to 3.77)), and night waking (1.36 (95% CI 1.07 to 1.72)), and in the reported use of steroids (19.9% v 64.1% of currently wheezy children). Nevertheless, the proportions reporting a visit to the GP at his/her surgery for wheeze in the previous year (prevalence ratio 1.15 (95% CI 0.91 to 1.45)) or an outpatient visit (0.98 (95% CI 0.49 to 1.94)) changed little and an increase in reported casualty attendance (1.66 (95% CI 0.89 to 3.07)) was non-significant. CONCLUSIONS: There is evidence of an increase in the prevalence of asthma among British primary school children between 1991 and 2002. The absence of a corresponding increase in health service utilisation data may reflect more widespread prophylactic treatment and/or changes in the use and provision of medical services.     

Prevalence and incidence of respiratory symptoms in relation to indoor dampness: the RHINE study

BACKGROUND: An association between indoor dampness and respiratory symptoms has been reported, but dampness as a risk factor for the onset or remission of respiratory symptoms and asthma is not well documented. METHOD: This follow up study included 16 190 subjects from Iceland, Norway, Sweden, Denmark, and Estonia who had participated in the European Community Respiratory Health Survey (ECRHS I). Eight years later the same subjects answered a postal questionnaire that included questions on respiratory symptoms and indicators of indoor dampness. RESULTS: Subjects living in damp housing (18%) had a significantly (p<0.001) higher prevalence of wheeze (19.1% v 26.0%), nocturnal breathlessness (4.4% v 8.4%), nocturnal cough (27.2% v 36.5%), productive cough (16.6% v 22.3%) and asthma (6.0% v 7.7%). These associations remained significant after adjusting for possible confounders. Indoor dampness was a risk factor for onset of respiratory symptoms but not for asthma onset in the longitudinal analysis (OR 1.13, 95% CI 0.92 to 1.40). Remission of nocturnal symptoms was less common in damp homes (OR 0.84, 95% CI 0.73 to 0.97). CONCLUSIONS: Subjects living in damp housing had a higher prevalence of respiratory symptoms and asthma. Onset of respiratory symptoms was more common and remission of nocturnal respiratory symptoms was less common in subjects living in damp housing.     

Lung function, respiratory illness, and passive smoking in British primary school children.

BACKGROUND: Many studies have reported a significant association between parents' smoking and reduced lung function in their children, but often the association has been found to be significant only in relation to maternal smoking. There have been few epidemiological studies on this topic in Britain. METHODS: Spirometry, in 2756 children aged 6.50-11.99 years, was carried out in a representative sample of English children, an inner city and ethnic minority sample, and a Scottish sample. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and forced expiratory flow rates of 25-75% and 75-85% (FEF25-75 and FEF75-85) were measured and standardised scores obtained separately for the English representative sample, the Scottish sample and subgroups in the inner city sample, white and Afro-Caribbean children and those originating from the Indian subcontinent. Multiple regression analyses were used to assess associations of FVC, FEV1, FEF25-75 and FEF75-85 with the passive smoking and respiratory illness, with adjustment for a large number of potential confounders. Passive smoking was defined in terms of reported number of cigarettes smoked at home by each parent. The respiratory symptoms and illnesses assessed were wheeze, asthma and bronchitis attacks, cough in the morning, and cough at any other time as reported by parents. RESULTS: Maternal smoking, but not paternal smoking, was associated with reduced FEF25-75 and FEF75-85 in boys. No association was found between passive smoking and lung function in girls, but in an analysis including both sexes the interaction of sex and parental smoking on lung function was not significant. With few exceptions, FEV1, FEF25-75 and FEF75-85 were reduced in children with wheeze and asthma attacks. CONCLUSIONS: The effect of passive smoking may depend on the close contact of a parent with a susceptible child as only maternal smoking in boys was significantly associated with impaired lung function. However, this explanation remains unsubstantiated. A parent's report of wheeze and asthma attacks in the child is reflected in reduced lung function.     

Prevalence of bronchial reactivity to inhaled methacholine in New Zealand children.

The prevalence of bronchial hyperreactivity to inhaled methacholine and of a clinical history of symptoms of asthma was determined in a birth cohort of 9 year old New Zealand children. A history of current or previous recurrent wheezing was obtained in 220 of 815 children. Of 800 who had spirometric tests, 27 (3.4%) had resting airflow obstruction (FEV1/FVC less than 75%). Methacholine challenge was undertaken without problem in 766 children, the abbreviated protocol being based on five breaths and four concentrations. A fall in FEV1 of more than 20% was observed in 176 children (23% of challenges, 22% of the full cohort) after inhalation of methacholine in concentrations of up to 25 mg/ml. The prevalence of bronchial reactivity in children with symptoms was related to the frequency of wheezing episodes in the last year, and the degree of reactivity to the interval since the last episode. Sixty four children (8.0%) with no history of wheeze or recurrent dry cough were, however, also responsive to methacholine 25 mg/ml or less, while 35% of children with current or previous wheezing did not respond to any dose of methacholine. Bronchial challenge by methacholine inhalation was not sufficiently sensitive or specific to be useful as a major criterion for the diagnosis of asthma in epidemiological studies. The occurrence of airway reactivity in children without symptoms of asthma, however, raises the possibility that adult onset asthma and the development of airways obstruction in some subjects with chronic bronchitis could have origins in childhood.     

Ethnic differences in prevalence of asthma symptoms and bronchial hyperresponsiveness in New Zealand schoolchildren

Maoris and Pacific Islanders in New Zealand have a higher asthma mortality and hospital admission rates than Europeans. To determine whether difference in asthma prevalence is the major factor underlying these differences in mortality, 2053 Auckland children aged 7-10 years (European 1084, Maori 509, Pacific Islander 460) were randomly sampled from school classes in the Auckland Urban Area, and studied by questionnaire (completed by parents) and histamine inhalation challenge to assess the provocative dose of histamine causing a 20% fall in FEV1 (PD20). Maoris had the highest prevalence rates of respiratory symptoms, and Europeans had rates similar to Pacific Islanders. For "any current wheeze" for example, the prevalence in Maoris was 22.2% compared with 16.1% and 16.3% in the Europeans and Pacific Islanders. The prevalence of diagnosed asthma was similar in the three groups. When bronchial hyperresponsiveness (defined as a PD20 less than or equal to 7.8 mumol histamine) was considered, Europeans had the highest rates (20%), followed by Maoris (13%), and then Pacific Islanders (8.7%). These differences were not accounted for by differences in socioeconomic status, rates of smoking in the home, age, gender, or height. It is concluded that differences in asthma prevalence do not satisfactorily explain the mortality and admission rate differences, although the higher symptom prevalence in the Maoris could be relevant to the higher mortality rate. Maori and Pacific Island children with symptoms of asthma were less likely to be taking prophylactic medication than European children. It is proposed that differences in management are important factors relevant to the increased mortality and morbidity from asthma in Polynesians.     

Microvascular complications in South African patients with long-duration diabetes mellitus.

OBJECTIVE: To determine the prevalence of microvascular complications in South African black and Indian patients with long-duration diabetes mellitus (DM). DESIGN: A retrospective analysis was undertaken of clinical records of 219 DM patients (132 black, 87 Indian) with long-duration DM (over 10 years) attending a diabetes clinic in Durban. Data recorded on each subject included demographic details (age, gender, ethnic group, type of diabetes, age of onset and duration of diabetes), presence of retinopathy, markers of nephropathy and biochemical variables. The prevalence of complications and the clinical and biochemical parameters were evaluated for type 1 and type 2 diabetes and for each ethnic group. RESULTS: Of the 219 patients, 47 had type 1 DM (36 blacks, 11 Indians) and 172 were classified as type 2 DM (96 blacks, 76 Indians). The mean age of onset of DM was later in blacks than Indians, both for type 1 (P < 0.05) and type 2 DM (P < 0.01). In patients with type 1 DM, the prevalence of retinopathy was 53.2% (blacks 55.6%, Indians 45.5%), persistent proteinuria was found in 23.4% (blacks 25%, Indians 18.2%) and hypertension in 34%. No ethnic difference was found except for the prevalence of hypertension which was higher in blacks than Indians (41.7% v. 9.1%, P < 0.5). Onset of retinopathy from time of diabetes diagnosis occurred earlier in blacks than Indians (13.0 +/- 4.6 yrs v. 18.0 +/- 4.6 yrs, P < 0.05). For the type 2 DM group, retinopathy was found in 64.5% (black v. Indian 68.8 v. 59.2%) and persistent proteinuria in 25% (black v. Indian 30.2 v. 18.4%). Hypertension was observed in 68% and was more prevalent in blacks (84.4 v. 47.4%, P < 0.01) There was an earlier onset of retinopathy (P < 0.05) and hypertension (P < 0.01) from time of diabetes diagnosis in blacks than Indians. In the type 1 DM group retinopathy was associated with a significantly longer duration of diabetes (P < 0.05) and higher glycated haemoglobin (HbA1) (P < 0.05). For type 2 DM subjects there was a significant association between retinopathy and longer duration of diabetes (P < 0.05) and higher systolic blood pressure (P < 0.05). CONCLUSION: This study has shown that there is a high prevalence of microvascular complications in South African patients with long-duration diabetes mellitus.     

Prolonged after-effects of pneumonia in children

Sixty-two black children were prospectively followed up for 1-7 years after pneumonia contracted at a median age of 17 months. In 55% of cases the pneumonia was measles-associated and 27% had serological evidence of infection with other respiratory viruses. Recurrence of cough or wheeze for more than 6 months occurred in 85% with just over 50% having recovered during the follow-up period. While the highest incidence of persistent symptoms occurred in children after measles superinfected with another virus, this was not significant. Abnormal radiographic features persisted in 53% of children and consisted of peribronchial and/or parenchymal lesions. Abnormal large and small airway calibre and/or bronchial hyperreactivity were found in one-third of children, and were significantly more common in those children whose main symptom was recurrent wheezing. Clinical and lung function abnormalities years after lower respiratory tract infection in this group of disadvantaged children compare with reports from more privileged groups. Recognition that long-term sequelae occur may prevent inappropriate subsequent management of symptomatic children.     

Nutrition and respiratory health in children in six Central and Eastern European countries

BACKGROUND: The results of studies on the effect of nutrition on respiratory diseases are inconsistent. The role of nutrition in children's respiratory health was therefore analysed within the cross sectional Central European Study on Air Pollution and Respiratory Health (CESAR). METHOD: A total of 20 271 children aged 7-11 were surveyed in six European countries. Respiratory health and food intake were assessed using questionnaires. Associations between four symptoms and nutritional factors were evaluated using logistic regression, controlling for area plus other potential confounders. RESULTS: All symptoms showed initial associations with nutritional factors. Low consumption of fish and of summer and winter fruit were the most consistent predictors. In a fully adjusted model low fish intake remained a significant independent predictor of persistent cough (OR=1.18; 95% CI 1.04 to 1.34), wheeze ever (OR=1.14; 95% CI 1.03 to 1.25) and current wheeze (OR=1.21; 95% CI 1.06 to 1.39) and a weaker predictor of winter cough (OR=1.10; 95% CI 0.99 to 1.23). Low summer fruit intake was a predictor of winter cough (OR=1.40; 95% CI 1.10 to 1.79) and persistent cough (OR=1.35; 95% CI 1.01 to 1.82). Low winter fruit intake was associated with winter cough (OR=1.28; 95% CI 1.09 to 1.51). Associations between symptoms and vegetable intake were inconsistent. Low summer intake was significantly associated with winter cough (OR=1.23; 95% CI 1.03 to 1.47) but, overall, winter intake had inverse associations with both coughs. Associations between winter vegetable intake and wheeze varied considerably between countries. CONCLUSION: A number of associations were found between respiratory symptoms and low intake of fish, fruit and vegetables in children. Low fish intake was the most consistent predictor of poor respiratory health. Fruit and vegetable intake showed stronger associations with cough than with wheeze.