title: Circulatory disease mortality in the Massachusetts tuberculosis fluoroscopy cohort study.
abstract: High-dose ionizing radiation is associated with circulatory disease. Risks from lower-dose fractionated exposures, such as from diagnostic radiation procedures, remain unclear. In this study we aimed to ascertain the relationship between fractionated low-to-medium dose radiation exposure and circulatory disease mortality in a cohort of 13,568 tuberculosis patients in Massachusetts, some with fluoroscopy screenings, between 1916 and 1961 and follow-up until the end of 2002. Analysis of mortality was in relation to cumulative thyroid (cerebrovascular) or lung (all other circulatory disease) radiation dose via Poisson regression. Over the full dose range, there was no overall radiation-related excess risk of death from circulatory disease (n = 3221; excess relative risk/Gy -0.023; 95% CI -0.067, 0.028; p = 0.3574). Risk was somewhat elevated in hypertensive heart disease (n = 89; excess relative risk/Gy 0.357; 95% CI -0.043, 1.030, p = 0.0907) and slightly decreased in ischemic heart disease (n = 1950; excess relative risk/Gy -0.077; 95% CI -0.130, -0.012; p = 0.0211). However, under 0.5 Gy, there was a borderline significant increasing trend for all circulatory disease (excess relative risk/Gy 0.345; 95% CI -0.032, 0.764; p = 0.0743) and for ischemic heart disease (excess relative risk/Gy 0.465; 95% CI, -0.032, 1.034, p = 0.0682). Pneumolobectomy increased radiation-associated risk (excess relative risk/Gy 0.252; 95% CI 0.024, 0.579). Fractionation of dose did not modify excess risk. In summary, we found no evidence of radiation-associated excess circulatory death risk overall, but there are indications of excess circulatory death risk at lower doses (<0.5 Gy). Although consistent with other radiation-exposed groups, the indications of higher risk at lower doses are unusual and should be confirmed against other data.
authors.affiliation: Radiation Epidemiology Branch, National Cancer Institute, Bethesda, MD, 20892-9778, USA. mark.little@nih.gov.|National Cancer Institute, Room 7E546, 9609 Medical Center Drive, MSC 9778, Rockville, MD, 20892-9778, USA. mark.little@nih.gov.
authors.forename: Mark P
authors.initials: MP
authors.lastname: Little
authors.affiliation: Department of Epidemiology and Biostatistics, School of Medicine, University of California San Francisco, San Francisco, CA, 94118, USA.
authors.forename: Lydia B
authors.initials: LB
authors.lastname: Zablotska
authors.affiliation: Radiation Epidemiology Branch, National Cancer Institute, Bethesda, MD, 20892-9778, USA.
authors.forename: Alina V
authors.initials: AV
authors.lastname: Brenner
authors.affiliation: Department of Pediatrics, Wayne State University School of Medicine and Children's Hospital of Michigan, Detroit, MI, 48201-2196, USA.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Lipshultz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000209:etiology / Q000401:mortality*; D002423:Cause of Death; D019583:Dose Fractionation, Radiation; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005471:Fluoroscopy / Q000379:methods*; D005500:Follow-Up Studies; D006801:Humans; D008168:Lung / Q000528:radiation effects; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000209:etiology / Q000401:mortality; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000401:mortality*; D011839:Radiation, Ionizing; D012307:Risk Factors; D013961:Thyroid Gland / Q000528:radiation effects; D014376:Tuberculosis / Q000000981:diagnostic imaging* / Q000453:epidemiology; D055815:Young Adult
keywords: Circulatory disease; Fluoroscopy; Hypertension; Ionizing radiation; Tuberculosis