Disclaimer: A Word of Caution - Association vs Causation

I just wanted to back up for a moment and talk about association vs causation. I myself had a lot of trouble with this when I first learnt about it, and I think it's worthwhile to mention it here. Most of the studies that I have cited here do not use randomized controlled trials because of it is unfeasible and impractical to do such studies on the environmental scale that I am considering risk factors for obesity and comorbid conditions.

Association or correlation basically means that there is a trend that seems to go along with another trend. So for example, one of the things that obesity seems to be related to is a lower socioeconomic status in a community. However this is an association and not a causation. The studies that have found this out are observational studies, and you cannot find out about causation from these studies.

Causation requires researchers to conduct experimental studies that control for variables, and have control groups to compare a certain experimental or intervention group. So for example, one of the studies talked about having specialty coffee shops having a protective associative effect on risk of obesity. This is only a correlation and does not mean specialty coffee shops will prevent obesity. The study needs to be accounted for by other explanations such as the fact that specialty coffee shops are often more densely placed in communities with higher SES demographics. 

As the Obesity Epidemic Grew

These maps basically sum up I am going to say in my next post about the extent of the obesity epidemic.

Why the First Chronic Epidemic?

Some defintions according to the World Health Organization,:
Epidemic: When there are more cases of that disease than normal
Pandemic:When there is a worldwide epidemic of a disease.

Since the inception of multinational organizations, and health services, public health officials have generally dealt with large scale epidemics and pandemics related to infectious diseases. When asked about epidemics in the past, things like smallpox, polio, and more recently HIV/AIDS come to mind. However, the rise in obesity and associated illnesses has been dramatic over the past few decades. Many factors contribute to this including lifestyle and occupational shifts in our population, changes in dietary patterns and how we consume our food, the way of infrastructure has developed, and socioeconomic and sociocultural factors. Over the next few entries, I am going to attempt to address each of these topics individually.

What is unique about the epidemic of obesity and associated illnesses is the fact that the health conditions are chronic. It is difficult to imagine using vaccines or other infection control mechanisms that have been a cornerstone in dealing with prior epidemics. Tackling chronic conditions merits attention at the systemic causes of the epidemic and will require unique interventions, many of which are unfamiliar to health care professionals. I will try to explore some of the strategies that have been used and assess their successes and failures. I will complement this with things I find in my own environment, that are characteristic of causes of this epidemic and approaches or solutions which have been beneficial to alleviate or prevent its progression.

By the Numbers

Obesity has been highly publicized in recent years. Receiving so much media attention, it is difficult for one to not be aware of high proportion of Canadians who are classified as being overweight or obese. As the tables below clearly demonstrate, we are dealing with a national crisis, that will severely impact our economy through rising health care costs and the associated lost productivity due to sick time, years of life lost, etc.


Body mass index over 25, self-reported, adult, by age group and sex
(Percent)

	2003	2005	2007	2008
	percent
Total, 18 years and over	49.4	50.0	50.8	51.1
Males	57.3	58.1	58.7	58.6
Females	41.3	41.8	42.9	43.5
18 to 19 years	19.6	23.5	21.5	25.6
Males	24.5	28.9	23.5	32.3
Females	14.4	18.2	19.6	17.6
20 to 34 years	39.7	39.3	40.6	40.3
Males	48.8	47.8	50.0	47.9
Females	29.6	29.9	30.4	32.0
35 to 44 years	49.5	50.8	51.2	51.8
Males	60.8	62.0	63.1	62.3
Females	37.3	38.8	39.2	40.9
45 to 64 years	57.7	58.1	58.3	58.1
Males	64.7	65.8	65.3	65.8
Females	50.6	50.2	51.3	50.4
65 years and over	53.8	54.1	56.1	56.7
Males	58.6	59.3	60.8	61.7
Females	50.0	49.8	52.2	52.7
Note: This indicator is measured out of 18 years and over only. Source: Statistics Canada, CANSIM, table 105-0501 and Catalogue no. 82-221-X. Last modified: 2010-01-05.