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Archive for September, 2010

New Melanoma & Breast Cancer Studies in Iceland got me wondering

Posted by D3forU on September 8, 2010

So I’m stumbling through new research papers, and stumble onto this one.

Unfortunately, it’s only an abstract, and not the full paper with some more details and information.

The first study relates to incidence, while the second relates to mortality.

Quote:
Am J Epidemiol. 2010 Sep 2. [Epub ahead of print]
A Melanoma Epidemic in Iceland: Possible Influence of Sunbed Use.

Héry C, Tryggvadóttir L, Sigurdsson T, Olafsdóttir E, Sigurgeirsson B, Jonasson JG, Olafsson JH, Boniol M, Byrnes GB, Doré JF, Autier P.
Abstract

Since 1980, sunbed use and travel abroad have dramatically increased in Iceland (64 degrees -66 degrees N). The authors assessed temporal trends in melanoma incidence by body site in Iceland in relation to sunbed use and travel abroad. Using joinpoint analysis, they calculated estimated annual percent changes (EAPCs) and identified the years during which statistically significant changes in EAPC occurred.

Between 1954 and 2006, the largest increase in incidence in men was observed on the trunk (EAPC = 4.6%, 95% confidence interval: 3.2, 6.0).

In women, the slow increase in trunk melanoma incidence before 1995 was followed by a significantly sharper increase in incidence, mainly among women aged less than 50 years, resembling an epidemic incidence curve (1995-2002: EAPC = 20.4%, 95% confidence interval: 9.3, 32.8). In 2002, the melanoma incidence on the trunk was higher than the incidence on the lower limbs for women.

Sunbed use in Iceland expanded rapidly after 1985, mainly among young women, and in 2000, it was approximately 2 and 3 times the levels recorded in Sweden and in the United Kingdom, respectively. Remember this fact, as I’ll come back to it later

Travels abroad were more prevalent among older Icelanders. The high prevalence of sunbed use probably contributed to the sharp increase in the incidence of melanoma in Iceland.

so I continue through my stumbling and come across this recent study. This is a complete paper on PubMedCentral so there is more info to look into.

Quote:
Disparities in breast cancer mortality trends between 30 European countries: retrospective trend analysis of WHO mortality database.

Autier P, Boniol M, LaVecchia C, Vatten L, Gavin A, Héry C, Heanue M.
International Agency for Research on Cancer, Lyon, France. philippe.autier@i-pri.org
Comment in:

Abstract

OBJECTIVE: To examine changes in temporal trends in breast cancer mortality in women living in 30 European countries.

DESIGN: Retrospective trend analysis. Data source WHO mortality database on causes of deaths Subjects reviewed Female deaths from breast cancer from 1989 to 2006

MAIN OUTCOME MEASURES: Changes in breast cancer mortality for all women and by age group (<50, 50-69, and >or=70 years) calculated from linear regressions of log transformed, age adjusted death rates. Joinpoint analysis was used to identify the year when trends in all age mortality began to change.

RESULTS: From 1989 to 2006, there was a median reduction in breast cancer mortality of 19%, ranging from a 45% reduction in Iceland to a 17% increase in Romania. Breast cancer mortality decreased by >or=20% in 15 countries, and the reduction tended to be greater in countries with higher mortality in 1987-9.

England and Wales, Northern Ireland, and Scotland had the second, third, and fourth largest decreases of 35%, 29%, and 30%, respectively. In France, Finland, and Sweden, mortality decreased by 11%, 12%, and 16%, respectively. In central European countries mortality did not decline or even increased during the period.

Downward mortality trends usually started between 1988 and 1996, and the persistent reduction from 1999 to 2006 indicates that these trends may continue. The median changes in the age groups were -37% (range -76% to -14%) in women aged <50, -21% (-40% to 14%) in 50-69 year olds, and -2% (-42% to 80%) in >or=70 year olds.

CONCLUSIONS: Changes in breast cancer mortality after 1988 varied widely between European countries, and the UK is among the countries with the largest reductions. Women aged <50 years showed the greatest reductions in mortality, also in countries where screening at that age is uncommon. The increasing mortality in some central European countries reflects avoidable mortality.

Looking into Table 1 of the last report, I find that Iceland is THE highest reduction in Breast Cancer Mortality overall, and also in the <50 crowd from 1989 – 2006, which is 10 years after sunbed usage increased in the similar age population, with a 76% reduction in that age group overall. The first year of decline in Breast cancer mortality <50 is 1995, 10 years after sunbed use , as noted in the first report, increased.

Am I just reading between the lines here, or is is possible that more UV exposure is inversely related to Breast Cancer mortality, and here is a place where sunbed use would be more directly responsible as solar UV is lacking in Iceland??

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Sunshine is good medicine. The health benefits of ultraviolet-B induced vitamin D production.

Posted by D3forU on September 1, 2010

Grant WB, Strange RC, Garland CF.

J Cosmet Dermatol. 003 Apr;2(2):86-98.

Sunlight, Nutrition and Health Research Center, 2107 Van Ness Avenue, Suite 403B, San Francisco, CA 94109, USA. wbgrant@infionline.net

Abstract

Most public health statements regarding exposure to solar ultraviolet radiation (UVR) recommend avoiding it, especially at midday, and using sunscreen.

Excess UVR is a primary risk factor for skin cancers, premature photoageing and the development of cataracts. In addition, some people are especially sensitive to UVR, sometimes due to concomitant illness or drug therapy.

However, if applied uncritically, these guidelines may actually cause more harm than good. Humans derive most of their serum 25-hydroxycholecalciferol (25(OH)D3) from solar UVB radiation (280-315 nm).

Serum 25(OH)D3 metabolite levels are often inadequate for optimal health in many populations, especially those with darker skin pigmentation, those living at high latitudes, those living largely indoors and in urban areas, and during winter in all but the sunniest climates.

In the absence of adequate solar UVB exposure or artificial UVB, vitamin D can be obtained from dietary sources or supplements.

There is compelling evidence that low vitamin D levels lead to increased risk of developing rickets, osteoporosis and osteomaloma, 16 cancers (including cancers of breast, ovary, prostate and non-Hodgkin’s lymphoma), and other chronic diseases such as psoriasis, diabetes mellitus, hypertension, heart disease, myopathy, multiple sclerosis, schizophrenia, hyperparathyroidism and susceptibility to tuberculosis.

The health benefits of UVB seem to outweigh the adverse effects.

The risks can be minimized by avoiding sunburn, excess UVR exposure and by attention to dietary factors, such as antioxidants and limiting energy and fat consumption.

It is anticipated that increasing attention will be paid to the benefits of UVB radiation and vitamin D and that health guidelines will be revised in the near future.


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