Sunday 7 July 2013

Inequalities in Health - Three English Towns

The inequalities in health by geography have been known for many years but the reasons are elusive. The phenomenon is particularly obvious for deaths from coronay heart disease (CHD), which has been the major cause of death in Europe and North America during the past 70 years (but not now). The reason for the variation has been and still is judged to be the result of faulty eating in those with the highest mortality, which in practice is those living in the north-west of England or the UK.

Three English towns have been studied in considerable detail.
Ipswich in south-east England has the lowest CHD mortality: 89 for men and 79 for women (Standardised mortality ratios (SMR), national average =100)
Stoke in the midlands has a CHD mortality SMR of 115 for men and 128 for women.
Wakefield in Yorkshire in the north of England has CHD mortality SMR of 115 for men and 137 for women.

We can see that mortality rates in Ipswich were below the national average, while those in Stoke and Wakefield were above the national average.

The study included data collection by house-to-house questionaires to establish dietary patterns. The expectation was more food, more fat, more sugar, more calories as we move north-west from Ipswich. In reality the opposite was determined. The residents of Wakefield in the north had the lowest nutrition intakes, most notably of fat, carbohydrate and total energy.



Diet and coronary heart disease in 3 English towns
Mean daily intakes of nutrients expressed as grams per day
Death expressed as Standardised Mortality Ratios, ages 35-74









Number
Energy
Fat
Carbohydrate
Sugar
Protein
Fibre
CHD
(MJ)
(g)
(g)
(g)
(g)
(g)
deaths
Men
Ipswich
119
10.8
107.9
308.7
120.3
85.4
20.7
89
Stoke
128
11.6
107.9
315.1
117.0
94.5
20.2
115
Wakefield
110
10.1
96.5
271.2
106.0
84.1
17.9
117
Women
Ipswich
129
7.1
73.0
192.2
76.5
64.3
15.1
79
Stoke
150
7.3
72.4
205.0
78.2
66.2
15.8
128
Wakefield
120
7.0
71.9
189.4
73.0
63.1
14.0
137
















Reference:
Cade JE, Barker DJP, Margetts BM, Morris JA. Diet and inequalities in health in three English towns. Brit Med J 1988; 296: 1359-1362.

This is clearly a most interesting study, undertaken in considerable detail and well-produced. But its impact seems to be about zero. The results did not fit in with conventional wisdom, the diet-cholesterol-heart hypothesis. This finding which completely contradicts the diet hypothesis has been sidelined during the past 25 years and it is not in collective knowledge. There are many more examples of this.

So, what is the reason behind the mortality gradient in the UK from the south-east to the north? Could it be something to do with the location of the towns and the climate rather than collective human behaviour? Could it be the greater sunshine exposure of those living in Ipswich in the southeast that gives the advantage?

I would not advocate lack of sunshine as being the cause of death from CHD, but it increases suceptibility. More sun is a good thing.




2 comments:

  1. Welcome to the world of blogging!
    I have been one of your greatest admirers since reading your wonderful and illuminating book on sunshine and vitamin d.
    It is rare at my age to make changes in lifestyle. I have always been interested in healthy living but after reading your book my attitude to sunshine was transformed. As a gardener I have always been out in the sun (and I understand life expectancy figures for gardeners are good- I think I now know why).
    Since reading your book I have been taking a 5000 unit of vitamin d soft gel every day....

    ReplyDelete
    Replies
    1. Thanks Roger
      Delighted that you enjoyed the book and that you are now following the Blog. Some of the posts will be borrowed from the book, providing information in smaller amounts.\David

      Delete