Tuesday, June 12, 2012

Geographical Distribution as a Risk Factor

While my partner and I were researching HPV related cervical cancers and trying to see if there was a geographical factor that contributed positively or negatively, I came across an article about a study done in Jingan County, China that specifically focused on this question.

The study took a group of women from different terrains and by excluding the known factors that increase the risk of cervical cancer were able to monitor the geographical influence on cancer.

China has about 132,000 new cases of cervical cancer reported each year which counts for 28 % of cases world wide. The study wanted to look and analyze  the relationship of risk factors and cervical cancer in rural populations in south east china by first gathering 16,767 women, age 25 and over, and asking them standard screening questions. They looked at their menstrual history, demographic, family history, marital status, and reproductive history. These women were then followed from 1974-1985. Within the last year, they were gathered again to answer questions regarding their personal habits, level of hygiene, sexual behavior, and partner's sexual behavior.
    The researchers then used statistical analysis and were able to then calculate the influence on just geography. What they found was that the risk was relatively high among women who lived in the mountains, moderate for those women in the hills, and lower for those who lived in the plains. They did also look into the other risk factors, which for them included age, and found that the age of incidence was a direct correlation with altitude.  Below is a figure containing all the data for the study.

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The conclusion of the study was that there is an connection between geography and cervical cancer which was seen after controlling all the other known risk factors leading the researchers to believe that there is something about geography that definitely plays a role in inducing cancer.

My question then is, what makes it a factor? Can it be proved globally that geography plays a role, or is there something that is specific to China that makes it a factor? Does the lifestyle of the Chinese people in those areas affect them and it is something that is so acute to their daily lives that researchers felt it was too small of significance to matter, but really is the determining factor? And if geography does play a role how do we fit that into an equation to make a proper treatment for cervical cancer?

Sorry for the many questions and a lack of answers, but as this was the only study done, there is no research out side of this to give answer or even help lead us in the right direction. Therefore, this needs to be done globally to see if other nations come to the same conclusion.

My thoughts are that geography does play a factor, however, as I lack in knowledge of geographic influence I can't say exactly why. However, I feel that because of the different cultures there will be some problems with the strength of the study. Different countries can have the same terrain but the people who live there can have different habits as a community that is unique to the culture/ country. There are too many variables that have to be taken into consideration that could cause the study to become inconclusive on a global scale, with the data rejecting each other.

I was wondering what everyone else thought on the matter. As stated before there are a lot of variables to consider, but I just wanted to see what other people thought.