Epidemiology of Interstitial Lung Disease

BACKGROUND: Although many investigations have been conducted to characterize the pathogenesis of interstitial lung diseases, few examined the epidemiology of these disorders in a general population. The establishment of the registry represented the first step in a sequence of investigations designed to characterize the epidemiology of the interstitial lung diseases. The registry initially served a descriptive purpose; the incidence of the interstitial lung diseases was measured in a defined population. Subsequently the registry served as a mechanism for ascertaining cases for a case-control study. Finally, the registry provided population-based data for clinical purposes on presentation, physiology, and natural history of the interstitial lung diseases. DESIGN NARRATIVE: The resources of the New Mexico Tumor Registry were adapted to identify new cases of interstitial lung disease in Bernalillo County. Other sources of information for identifying new cases included pulmonary physicians, primary care physicians, death certificates, and autopsies. After a case of interstitial lung disease had been identified from the various sources of information, data collection included an interviewer-administered symptoms questionnaire, abstracted medical record data, phlebotomy for measurement of serum precipitins, and evaluation of available chest x-rays and biopsy materials. Follow-up was used to determine the natural history of the disease. The study was renewed in 1993 to complete the work conducted from 1988 through 1992. Case-ascertainment, data collection, and follow-up of incident cases of ILD identified during the period 10/1/88-9/30/92 were completed. The incidence of ILDs was described. The clinical characteristics of patients with ILDs were described. The prognosis of the most common ILDs were described.