Cities of sickness: pollution, dementia and the modern condition

The researchers had obviously seemed to be on the ball with this one, taking into account access to neurologists, exposure to various pollutants, and adjustments made for the contexts of such conditions as brain injury, diabetes and neighbourhood income.

The findings indicate that the large cohort featuring the older population focused and living in proximity to heavy traffic "was associated with higher incidence of dementia, but not with Parkinson's disease or multiple sclerosis." One in 10 cases were identified for those living near roads affected by noise and air pollution.

The work is another clarion call about the vicissitudes of relentless urbanisation. As the lead scientist on the project Hou Chen explained,

Increasing population growth and urbanisation has placed many people close to heavy traffic, and with widespread exposure to traffic and growing rates of dementia, even a modest effect from near-road exposure could pose a large public health burden.

As is the nature of the business of risk, other scientists urged caution. Don't up stakes and go to the country just yet. "The analyses are exceedingly complex," suggested neuroscientist John Hardy of the University College of London, "and this always leads to concerns that the analytic complexity is hiding confounding factors in the analytic pipeline." By no means a reassuring statement.

Despite throwing some cold water on the Ontario study, Hardy can hardly dispel the firm notion that cities are places of increasing sickness, at both the bodily and mental level. The propaganda about well-being is everywhere; the clinics are getting busier. The human being is in a state of suffering, and urban planners will be smacking their lips at the prospect of more employment. Sickness, as it has was in the past, will continue being good for business.