The natural history of asthma in childhood.

Abstract

SUMMARY The incidence and prognosis ofchildhood asthma and wheezing illness (AW) was studied using data obtained at ages 7, 11, and 16 from a national cohort of 8806 children born in 1958. By the age of 16, 24-7% were reported to have experienced at least one episode of AW. In 18-3% AW had started before the age of 8, but only 4-2% continued to have symptoms in later childhood. A further 3-6% began to have AW between the ages of 8 and 11, and 2-8% began between the ages of 12 and 16. Ofthose with AW at age 7, 28 3% had symptoms at 11 and 16 5% at 16; these proportions were about doubled if AW at 7 had been severe. The associations between natural history and a large number of perinatal, social, environmental, and medical factors were examined. Those which predicted the onset of AW after the age of 7 were: male sex ofchild; mother aged 15-19 at child's birth; history of pneumonia, whooping cough, throat or ear infections or tonsillectomy; eczema, allergic rhinitis; and periodic vomiting or abdominal pain.To understand the natural history of asthma, a description of both its incidence and prognosis is required. Prevalence rates obtained by cross-sectional population studies reflect only the net effect of incidence and prognosis, and those relying on retrospective assessments have the additional problem ofinadequate and selective recall. With one exception' previously reported cohort studies have been essentially follow up studies designed only to study prognosis since only subjects with asthma were seen subsequently.2-5The National Child Development Study,6 which originated in the National Perinatal Study,7 has followed up at ages 7, 11, and 16 nearly every child in England, Scotland, and Wales born in one week of March 1958. Data, which were collected by parent interview and physical examination of the child, comprised a wide variety of perinatal, medical, social, behavioural, and educational variables. Since the study was not designed to investigate the natural history of asthma there were, not unexpectedly, shortcomings in the assessment of both asthma and the range of aetiological factors. Nevertheless the size and representativeness of this national cohort offer a unique opportunity to examine the natural history of asthma and wheezing illness. MethodsInformation about current and past asthma or wheezing was obtained as part of a structured questionnaire on medical and other topics administered to parents by health visitors. Data for all three interviews (at ages 7, 1 1, and 16) were obtained for 8806 of the original cohort of 17419 births comprising the 1958 Births Survey (98% ofall births in that week). Most ofthe analysis in this paper relates to the 8806 children with complete data, but, as we shall show, there was no evidence of a difference in asthma and wheeze between these children and those for whom data were incomplete.The form of the questions on asthma or wheezing differed at each age. At age 7, parents were asked whether their child had ever had "attacks of asthma," and the same question was repe...

Prevalence of wheeze during childhood: retrospective and prospective assessment

“…This compares favourably with other cohort studies [9,15]. Over 20% of children aged 8± 13 reported current wheeze and 39% reported "wheeze ever".…”

“…Surveys in older children and adults, however, suggest that a substantial proportion of childhood symptoms is forgotten later in life [9±11, 19]. In the large British National cohort, first surveyed at age 7 yrs, the prospectively assessed cumulative prevalence by age 11 yrs was twice as high as the retrospective prevalence by age 11 (22 versus 12%) respectively, and the difference persisted at age 16 yrs (25% versus 12%) and 33 yrs (43% versus 28%) [9,19]. In Tasmania, 1,494 children recruited at age 7 were questioned when aged 30.…”

“…The main reason may be the age range of the observation period: recall by parents may be better for events in early childhood, when the child/ parent contact is closer, than in the older age-groups (7±23 yrs) studied in the British National cohort [9,10]. In Tasmania, the answers of grown-up offspring was compared with previous questionnaires answered by their parents [11].…”

“…Most longitudinal surveys of childhood wheeze have been conducted in late childhood [9,10], or even adults [11], so that poor recall seems likely. Parental recall may be more reliable when children are relatively young.…”

Prevalence of Asthma and Allergic Diseases among Children 13-14 Years in Lubumbashi/Drcongo

“…The City of Lubumbashi is a region with strong mining activity and it is victim of pollution from mining companies. According to the literature, the evaluation of Wheezing respiratory follows a global trend, which is linked to air pollution as supported Anderson [13].We cannot confirmed that our prevalence of 11.28% of respiratory wheezing is due to the pollution from mining within the city of Lubumbashi. When we evaluate the wheezing history in a period of 12 months, we find that our results are low compared to those found by Koffi in Côte d'Ivoire [8], and by Pearce in the various cities in Europe [14].…”