Incidence of asthma in adults – report from the Obstructive Lung Disease in Northern Sweden Study

Abstract

Incidence studies offer a better opportunity to study risk factors for asthma than do prevalence studies. However, regular prospective follow-ups of large cohorts are difficult to perform, and that is why direct measurement of the incidence rate of asthma is almost impossible. Thus, cross-sectional follow-up studies of defined cohorts can be used to provide data on incidence. In 1986, a postal questionnaire survey on respiratory symptoms and diseases was performed in the northernmost province of Sweden. The population sample comprised all subjects born in 1919-20, 1934-5, and 1949-50 in eight representative areas of the province, which comprises 25% of the total area of Sweden. Completed answers were given by 5698 subjects (86%) of the 6610 subjects invited to the study. In 1992, the cohort was invited to a follow-up survey during the same season as in 1986, and 6215 subjects were traced. Of the 5393 subjects who answered the questionnaire, 4932 had participated in the 1986 survey, or 87% of those who participated in 1986. For the period 1986-92, the cumulative incidences of asthma were 4.9 and 5.0%, respectively, as assessed by the questions, "Have you ever had asthma?" and "Have you been diagnosed as having asthma by a physician?" Thus, the results indicate a mean annual cumulative incidence of asthma of 0.8%. After correction of the results for subjects who were diagnosed as having asthma in the clinical part later in the 1986 study, the mean annual cumulative incidence of asthma was found to be 0.5%. Risk factors were family history of asthma (OR 3.46) and current and former smoking, while female sex was a strong trend.

A prospective study of asthma incidence and its predictors: the RHINE study

“…However, some recent longitudinal studies have reported different rates. RÖ NMARK et al [4] from Sweden found an incidence rate of 5 cases?1,000 person-yrs -1 among adults; the high incidence may be caused by the higher ages in the sample, 42-73 yrs. In one Canadian study [17], a remarkably high incidence was found, y6 cases?1,000 person-yrs -1 among males and 12 cases?1,000 person-yrs -1 among females, all 25-54 yrs of age.…”

“…The diagnostic criteria for new-onset asthma have been based on either clinical investigations, or self-reported asthma or physician-diagnosed asthma [1,2]. Reports on asthma are more common and, over the last 10 yrs, questionnaire-based incidence studies have been published in the USA, Scandinavia, Spain and Italy, showing incidence rates from 1-5 cases per 1,000 person-yrs -1 [3][4][5][6][7][8][9]. It is difficult to decide which subjects should be excluded from the baseline population in a prospective study of asthma incidence.…”

Whole-cell pertussis vaccine protects against Bordetella pertussis exacerbation of allergic asthma

“…The prevalence of asthma and allergic disease has in-401 creased in many countries [39,40] and there has been spec- asthma and allergies in U.S. children [24].…”

“…Th2 cells secreting IL-4, IL-5, and IL-13 play a 39 central role in initiating and sustaining the asthmatic response 40 in this model [8]. While Th2 cells promote airway inflamma-41 tion in asthma, it has been proposed that Th1 cells protect 42 against allergic disease by antagonizing Th2 activity.…”

Impacto de un sitio de disposición final de residuos sólidos en la salud respiratoria de los adultos mayores

“…La presencia de síntomas respiratorios también se encontró asociada a otros factores descritos en la literatura científica, como factores de riesgo para la presencia de enfermedad respiratoria en la población adulta mayor, como son la edad, el sexo (29,30), el consumo de cigarrillo (31,32), la humedad en la vivienda (33)(34)(35)(36), la condición socioeconómica (37)(38)(39)(40), la afiliación a la seguridad social, la presencia de enfermedades concomitantes y otras fuentes de contaminación atmosférica como la ocupacional (41,42) y la cercanía a cultivos de caña de azúcar, que son quemados para su cosecha (43).…”