Cloudiness and Breast Cancer
Noblis, 3150 Fairview Park Drive South, Falls Church, Virginia
- *Corresponding Author:
- Dr. Ivanka Stajner
Noblis, 3150 Fairview Park Drive South
Falls Church, Virginia
E-mail: [email protected]
Received Date: October 29, 2009; Accepted Date: November 26, 2009; Published Date: November 26, 2009
Citation: Stajner I (2009) Cloudiness and Breast Cancer. J Cancer Sci Ther 1: 034-040. doi: 10.4172/1948-5956.1000006
Copyright: © 2009 Stajner I. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Traditional risk factors for breast cancer explain only a fraction of cases. Causes for trends in breast cancer incidence are not fully understood. Breast cancer incidence and mortality rates decrease with environmental conditions that promote Vitamin D synthesis in human skin including lower latitude and higher personal exposure to sunlight. Association of temporal variability in breast cancer incidence with changes in cloudiness, which decrease human Vitamin D synthesis is investigated. Association between temporal changes in breast cancer incidence and in the autumn cloudiness for preceding years is computed using data for the United States. There is a correlation of 0.96 (95%CI=0.92-1) between the time series of breast cancer incidence in the age group of 70-79 years and the average cloudiness in October during preceding 20 years. An empirical model for breast cancer incidence using autumn cloudiness in preceding years captures a rapid increase in breast cancer incidence in the 1980s and some of its yearto- year variability. Increased autumn cloudiness is associated with increased subsequent breast cancer incidence. Proposed mechanism includes blocking of solar ultraviolet radiation by thick clouds and decreasing the synthesis of Vitamin D in human skin. The findings suggest a new connection between climate variability and human health.