Reconcilable Differences: Discussion
Although there was no association between age, gender, or genotype and SA P-agonist use, we identified a strong and significant association between SES and the amount of SA P-agonist medications used by asthmatics, independent of asthma severity. This association was consistent across all proximate and contextual measures of SES, with gradients identified in the expected directions. This study provides the first evidence suggesting that poorer outcomes in lower SES asthmatics may not be associated solely with greater asthma severity as previously postulated, but rather also to poorer asthma control, despite universal access to health care. whitening gel
Three studies that have reported a higher prevalence of more severe asthma in lower-SES children measured asthma severity based on symptoms alone, and may therefore be demonstrating poorer control rather than greater severity. The two studies- that have attributed poorer outcomes in lower-SES patients with asthma specifically to greater severity have significant limitations. Using survey data, Littlejohns and McDonald found that adults in the lower two quin-tiles of SES based on the Registrar General’s classification of occupation were twice as likely to have disabling asthma, defined as “severe or frequent bouts of breathlessness, wheezing, or coughing which limit daily activities” as those in the upper 40%. This definition of greater severity could also represent poorer control. Similarly, a Canadian study based on administrative health-care data found that low-income adults were admitted to hospital more frequently, had more physician contacts, and were less likely to be assessed by a specialist, without any evidence of more fragmented care or a higher prevalence of asthma in the lower classes. Thus, without any metric for asthma severity, these authors deducted that the lower-income asthmatic patients had more severe disease. By directly assessing patients, we were able to overcome these limitations, and the negligible differences in the crude and adjusted ORs for SES suggest that confounding by disease severity may be less than expected.