June 16, 2003
The epidemiological evidence connecting TB with socioeconomic deprivation is long-standing. Several studies have found neighborhood crowding to be strongly associated with TB rates; in one study, the association persisted even after control for AIDS prevalence.
The authors conceived the present study out of concern that the close association between poverty and TB may have been complicated by immigration patterns in the past decade, with potential consequences for TB treatment and control. If many TB patients are now concentrated in socioeconomically advantaged areas, the traditional health department model of care designed for populations in socioeconomically depressed areas may not be applicable.
The researchers analyzed TB case data collected by the New Jersey Department of Health and Senior Services for the years 1994-1999. During that time, 4,295 TB cases were identified in New Jersey: 2,290 were U.S.-born residents, one was Canadian-born, and 2,004 were other foreign-born residents. Of the 2,005 foreign-born cases, 991 (49.4 percent) were born in countries designated by the World Health Organization as high-burden TB countries. During this period, New Jersey averaged 30.1 cases per 100,000 foreign-born persons and 5.8 per 100,000 among U.S.-born persons.
The researchers found that foreign-born patients resided in more affluent, more educated, and less crowded areas than did U.S.-born patients. Foreign-born patients were more likely to have been employed during the two years prior to diagnosis. Private physicians treated the majority of South Asian-born patients.
Based on their research, the authors pointed out several implications for TB control:
"Our analysis has revealed that the underserved population residing in urban areas long recognized to be at risk for TB lives alongside another population whose relative personal affluence and location defy time-honored epidemiological notions. There is substantial variability among foreign-born patients with respect to both personal and environmental socioeconomic indicators," the authors concluded. "As a result, future progress in TB control and elimination in the United States will require more complex solutions than have previously been recognized. TB among foreign-born residents and their children will continue to be a challenge to TB control measures, a challenge likely to persist as long as TB remains endemic in much of the developing world."