Page 31 - ADULT-ONSET ASTHMA PREDICTORS OF CLINICAL COURSE AND SEVERITY

REMISSION OF ADULT-ONSET ASTHMA
HOW OFTEN DOES ASTHMA REMISSION OCCUR IN ADULTS?
The remission rate in adult-onset asthma is much lower 87, 88 compared to childhood-onset asthma where 29-65% of the pa ents is in remission in early adulthood 89-91. The incidence of remission in adult-onset asthma pa ents varies from 0.6% to 2% per year 59, 90, 92-94. A markedly increased chance of remission has been observed retrospec vely in the period shortly (4-7 years) a er onset of the disease, a er which it decreases quickly 90. Interpre ng and comparing the di erent incidences found is further complicated by the considerable variability in the de ni on of asthma remission. The de ni on varies from just absence of symptoms to complete normaliza on of bronchial hyperreac vity or no need for asthma treatment anymore. In the current paragraph we did not adhere to one speci c de ni on.
PREDICTING REMISSION IN ADULT ASTHMA
Several cohort studies have been performed to nd factors associated with asthma remission, albeit mainly in mixed childhood and adult-onset asthma popula ons. In most studies gender was not signi cantly associated with remission 59, 88, 92, 94. Except in one study where men were more likely to go into remission 90. Asthma remission occurs more o en in younger subjects92, 93 and in subjects with a short disease dura on 90, 93. Pa ents with a higher age of asthma-onset were less likely to have asthma remission 88, 90, 95, as were middle aged and elderly pa ents 92. In contrast, others observed an increased remission rate in females with a higher age at diagnosis 68.
Asthma remission is most commonly seen in pa ents with mild asthma. In many studies this was characterized by minimal levels of symptoms or complete asthma control and low dose asthma medica on use at baseline 59, 68, 93, 94, 96, 97. Whereas pa ents with no or par al asthma control were very unlikely to be in remission at the end of follow-up, this accounts for both early and late-onset asthma 68, 93, 98, 99. Moreover, pa ents in remission had a higher FEV1 at baseline 59, 93, 95 and the highest increase in FEV1 during follow-up compared to pa ents with persistent asthma 93. Comorbid condi ons, such as allergic sensi za on or rhini s, are more o en absent in pa ents in remission 59.
An important external in uen al factor is smoking. One study found the years of smoking prior to the onset of asthma were signi cantly lower in pa ents with asthma remission a er a follow-up period 88. Furthermore, remission occurs more frequent in non-smokers or ex- smokers as compared to current smokers 59, 94. Finally, cessa on of smoking during the follow- up period increased the odds of having asthma remission by 6 mes 92.
THE PROGNOSIS OF ADULT-ONSET ASTHMA
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