July 01, 2015

That evil diabetes

The prime whipping boy for the "war on obesity" is diabetes.  Being fat is supposed to give you diabetes, never mind that most fat people are not diabetic! So it is interesting to see what pops up in the research about diabetes.  And the latest study is an unusually strong one.  The researchers had data on both income and education, which makes it quite a rarity and worth mentioning for that alone. So the results can be accepted without the most usual caveat about the influence of social class.

Another usual caveat is however not excluded. By basing their conclusions on interquartile range they threw away half their data.  At least they did not use extreme quintiles, I suppose. So they are a bit up on a lot of other studies in that regard.  The bottom line, however, is that the effects they observed were weak.

So what did they find, albeit weakly?  The most interesting finding was a negative.  Neighborhood social environment was not associated with diabetes.  Bear in mind, however that race/ethnicity was controlled for.  Without that control, inner city environments would have been found to be bad for you.  So having congenial neighbors is nice but it doesn't protect you from diabetes. Not terribly surprising, I suppose, but with their tendency to blame everything on external factors, Leftists might not like it

The positive effects were that a neighborhood with good opportunities for exercise helped stave off diabetes and a neighborhood with more fresh food available helped a little too.  So having nearby parks to jog around was good for you and a less fat-intensive diet gave your pancreas a bit of a rest.

An amusing thing is that JAMA really liked that study and put up a laudatory commentary on it ("Risk for Type 2 Diabetes Mellitus:  Person, Place, and Precision Prevention").  And what the commentary said about it did not surprise me one bit. The commentary disregarded the weaknesses of the effects and even said that the authors found something which they did not.  Academics have a great tendency to draw conclusions they want to draw and damn the evidence.  So when dear little Nancy Adler and Aric Prather said in their commentary that: "physical and social contexts of neighborhood environments matter for disease onset", they were ignoring the fact that the study below found that social environment did NOT matter.  LOL.

We climate skeptics know well how little there is behind Warmist "science" but the same is true of science in other fields too, particularly health science.  And Leftism of course floats on a sea of lies.  The situation is so bad that, even at age 71, I feel I still have to keep going and keep pointing out the facts. I would rather spend my time watching operetta -- but fortunately I do get some time for that too.  Much more fun than politics and crooked science.

Longitudinal Associations Between Neighborhood Physical and Social Environments and Incident Type 2 Diabetes Mellitus: The Multi-Ethnic Study of Atherosclerosis (MESA)

By Paul J. Christine et al.

ABSTRACT

Objective:  To determine whether long-term exposures to neighborhood physical and social environments, including the availability of healthy food and physical activity resources and levels of social cohesion and safety, are associated with incident T2DM during a 10-year period.

Design, Setting, and Participants:  We used data from the Multi-Ethnic Study of Atherosclerosis, a population-based cohort study of adults aged 45 to 84 years at baseline (July 17, 2000, through August 29, 2002). A total of 5124 participants free of T2DM at baseline underwent 5 clinical follow-up examinations from July 17, 2000, through February 4, 2012. Time-varying measurements of neighborhood healthy food and physical activity resources and social environments were linked to individual participant addresses. Neighborhood environments were measured using geographic information system (GIS)– and survey-based methods and combined into a summary score. We estimated hazard ratios (HRs) of incident T2DM associated with cumulative exposure to neighborhood resources using Cox proportional hazards regression models adjusted for age, sex, income, educational level, race/ethnicity, alcohol use, and cigarette smoking. Data were analyzed from December 15, 2013, through September 22, 2014.

Main Outcomes and Measures:  Incident T2DM defined as a fasting glucose level of at least 126 mg/dL or use of insulin or oral antihyperglycemics.

Results:  During a median follow-up of 8.9 years (37?394 person-years), 616 of 5124 participants (12.0%) developed T2DM (crude incidence rate, 16.47 [95% CI, 15.22-17.83] per 1000 person-years). In adjusted models, a lower risk for developing T2DM was associated with greater cumulative exposure to indicators of neighborhood healthy food (12%; HR per interquartile range [IQR] increase in summary score, 0.88 [95% CI, 0.79-0.98]) and physical activity resources (21%; HR per IQR increase in summary score, 0.79 [95% CI, 0.71-0.88]), with associations driven primarily by the survey exposure measures. Neighborhood social environment was not associated with incident T2DM (HR per IQR increase in summary score, 0.96 [95% CI, 0.88-1.07]).

Conclusions and Relevance:  Long-term exposure to residential environments with greater resources to support physical activity and, to a lesser extent, healthy diets was associated with a lower incidence of T2DM, although results varied by measurement method. Modifying neighborhood environments may represent a complementary, population-based approach to prevention of T2DM, although further intervention studies are needed.

JAMA Intern Med. Published online June 29, 2015. doi:10.1001/jamainternmed.2015.2691

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