Neriishi, K., Nakashima, E., Minamoto, A., Fujiwara, S., Akahoshi, M., Mishima, H. K., Kitaoka, K. and Shore, R. E. Postoperative Cataract Cases among Atomic Bomb Survivors: Radiation Dose Response and Threshold. Radiat. Res. 168, 404–408 (2007).
Recent evidence argues against a high threshold dose for vision-impairing radiation-induced cataractogenesis. We conducted logistic regression analysis to estimate the dose response and used a likelihood profile procedure to determine the best-fitting threshold model among 3761 A-bomb survivors who underwent medical examinations during 2000–2002 for whom radiation dose estimates were available, including 479 postoperative cataract cases. The analyses indicated a statistically significant dose–response increase in the prevalence of postoperative cataracts [odds ratio (OR), 1.39; 95% confidence interval (CI), 1.24–1.55] at 1 Gy, with no indication of upward curvature in the dose response. The dose response was suggestive when the restricted dose range of 0 to 1 Gy was examined. A nonsignificant dose threshold of 0.1 Gy (95% CI, <0–0.8) was found. The prevalence of postoperative cataracts in A-bomb survivors increased significantly with A-bomb radiation dose. The estimate (0.1 Gy) and upper bound (0.8 Gy) of the dose threshold for operative cataract prevalence was much lower than the threshold of 2–5 Gy usually assumed by the radiation protection community and was statistically compatible with no threshold at all.