1. State your health outcome of interest. I am interested in racial-based disparities that contribute to differential access to a diagnostic evaluation for interstitial lung disease (ILD). One possible health-related behavior that may influence diagnostic evaluation is smoking. Smoking is a risk factor for the development of interstitial lung disease, but is also a major risk factor for other causes of chronic lung disease, most notably Chronic Obstructive Pulmonary Disease. Moreover smoking is a contraindication to some of the therapeutic options for ILD, including specific pharmacologic therapies (anti-fibrotics) and lung transplantation. Another is healthcare resource utilization. This is undoubtedly complicated by issues of access to care, but patients who are more regularly followed in the healthcare system are more likely to receive preliminary diagnostic testing and evaluation that may raise suspicion/concern for ILD (chest x-ray, pulmonary function tests, CT chest) earlier.
2. Describe how you would study the role of one of the behaviors described for question #1 and your health outcome of interest. Incorporate a social factor (e.g. race/ethnicity, social exclusion, stress) in the study approach.
The behavior I am most interested in evaluating is the relationship between health care resource utilization and diagnostic evaluation for interstitial lung disease. Anecdotally, as an ILD center of excellence, our referrals include a diverse population of patients ranging from those with suspected ILD in whom minimal workup has been done to patients with a confirmed diagnosis of ILD in whom there are questions regarding management. There seems to be significant clinical variability not only in when patients are referred but also in the clinical diagnostic and management paths that follow. It is suspected and generally accepted that we are diagnosing patients with ILD well into the disease course, when irreversible loss of lung function has often occurred. However, in order to intervene earlier, we must make a diagnosis earlier in the disease course. Making use of the information currently available, this requires both an increased index of suspicion in patients with specific risk factors and a better understanding of how patients are currently interfacing with the healthcare system prior to diagnosis. Characterizing the current script(s) for pre-diagnostic ILD care can identify areas that would benefit from targeted interventions that provide stakeholder support. Implicit in this conversation is the possibility of social factors influencing healthcare utilization. The challenge in studying these questions is the ability to collect longitudinal data on patients with a rare disease. To this end, a relatively closed, integrated health care system is ideal. Using the Kaiser Permanente Northern California, I would use previously validated code-based algorithms to identify patients with specific subtypes of ILD known to case progressive scarring of the lungs and the index the date of diagnosis. I would then evaluate key healthcare resource utilization markers (chest imaging, pulmonary function tests, outpatient visits, hospitalizations) in the pre/post diagnosis period to describe variation in the clinical evaluation of patients and then determine if there are differences across race and gender.
3. If key health behaviors (e.g. smoking, exercise, nutritious diet) are strongly influenced by neighborhood, income, and/or education, do we need to continue to study how these behaviors influence health outcomes? Why or why not?
Yes. Many behaviors are influenced by structural factors, however identifying the layers of factors at play enables researchers to create more accurate models for potential causal pathways and to interventions that are best designed for target populations.