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The demographic transition. 60. mature. post. pre-modern. industrializing. industrial. industrial. 50. 40. Births. Population. 30. Birth or death rate per 1000 per yr. 20. Deaths. 10. 0. 0. 20. 40. 60. 80. 100. 120. 140. Years.
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The demographic transition 60 mature post pre-modern industrializing industrial industrial 50 40 Births Population 30 Birth or death rate per 1000 per yr 20 Deaths 10 0 0 20 40 60 80 100 120 140 Years
Lifestyle diseases: the burden of choice? CHRISTOPHER DYE • What are "lifestyle" diseases? • Disease burden we suffer by choice? • The agony of reversing the choice?
Lifestyle diseases: the burden of choice? CHRISTOPHER DYE • Diseases of civilization • Western disease paradigm • Diseases of affluence • Chronic diseases • Non-communicable diseases • Diseases of longevity
Where 60 million people die double burden of disease in low-income countries 8 Low-middle income High income 6 Deaths per million population 4 2 0 Communicable, Non- Injuries pregnancy, communicable nutrition
Chronic diseases?Non-communicable diseases? • Cardiovascular disease: heart disease, stroke • Cancer • Chronic respiratory diseases • Diabetes
going down slowly going up
Chronic, non-communicable diseases in long-lived populations
Life begins at 40? Conception in women, England & Wales, 2005 140 120 Menopause age 50 Median age menopause ≈ 50 years 100 80 Conceptions per 1000 women 60 40 20 0 Under Under Under 20–24 25–29 30–34 35–39 40 and 16 18 20 over
Why we age and dieKirkwood's "disposable soma" Evolution acts through reproduction Survival depends on maintenance, which is costly after reproduction
Zen 禅 and the art of metabolic maintenance? Survival of hunter-gatherers and Japanese 100 80 60 Percent surviving 40 20 0 0 20 40 60 80 100 Age (years)
Fixing the faults?"in the end costs exceed benefits" "…as each life-limiting process is countered, some other process will become limiting" Doug Wallace U California
Smoking deaths are higher in northern England and London
"I have taken more out of alcohol than alcohol has taken out of me" …only two before breakfast
Cancer: a glimpse of immortality Cancerwhen somatic cells revert by accident to germ-like cells Immortal germ cells Mortal somatic cells Cancer cells
"Dozens of new cancer genes found"Nature, 8 March 2007 Cancer caused by genetic (DNA) defects 500 genes in 200 kinds of cancer The bad news… More new cancer genes (≈100) than expected (≈ 10) ..and the worse news Cancer genomes carry many unique abnormalities, not all mutations contribute equally Diverse, unpredictable, causes
US Cancer Incidence Trends (1975-2003) for Top 10 sites 1975 2003 Men 1975-92 increase 1992-95 decrease 1995-03 stable Women 1975-79 stable 1979-03 increase
Genetic differences account for up to ¼ variation in life span Danish, Finnish, Swiss twins Born 1870-1910 20,502 same sex pairs No genetic influence on longevity before age 60 Chance of living to be 100 in: Woman whose sister lives to 100 4% vs 1% Man whose sister lives to 100 0.4% vs 0.1% K Christensen
Genetic differences account for up to ¼ variation in life span Weak correlation in longevity of twins
What to pack for the "Fantastic Voyage"? 3 bridges to immortality… Bridge One current knowledge to slow down the aging process Bridge Two advances in biotechnology to stop disease and reverse aging Bridge Three (nano)technology to create man-machine interface, expanding physical and mental capabilities
"Moneypenny, I'm to eliminate all free radicals"J Bond (Goldfinger) Free radicals: by-products of respiration, stabilized by oxidizing (and damaging) proteins, carbohydrates, fats, DNA Antioxidants: in fruits/vegetables, prevent oxidation Fantastic Voyage: the more supplements the better Science: "stick to tea, fruit, veg, wine in moderation – until more evidence"
Maltesers: not lighter than airBritons 2nd most obese in Europe Percent population with Body Mass Index 30+ EU countries 25 UK population ranked #2 20 15 % population obese (BMI 30+) 10 5 0 UK Italy Spain Malta Latvia Cyprus Austria Poland Ireland France Estonia Norway Finland Iceland Greece Sweden Belgium Hungary Portugal Slovakia Bulgaria Romania Slovenia Germany Lithuania Denmark Switzerland Netherlands Czech Republic
Obesity in Englandhighest in midlands and north Lowest in: London South east South west
The obesity epidemic: too much food, too little exercise? Why the "Big Two" just won't do "evidence that they are the main cause of the epidemic - or that halting them would reverse it - is "largely circumstantial" (20 obesity experts) "We threw tens of millions of dollars at the best investigators in the world - and they found absolutely no effect" (David Allison, University of Alabama) International Journal of Obesity 2006
The "obesogenic environment" 10 other possible explanations • Not enough sleep (obesity <=> sleep) • Warm houses demand less personal energy • Less smoking • Overweight mothers have overweight children • Overweight mothers have more children • Older mothers have overweight children • Older people are heavier • Drugs (hypertension etc) induce weight gain? • Environmental pollution (hormone interference) • Like (fat) marrying like (fat)
Life before birth:Fetal origins of adult disease David Barker's "Early Origins Hypothesis" (1986) Links low birth weight to increased risk of chronic disease in later life Osteoporosis, chronic obstructive lung disease, polycystic ovary syndrome, cancers of the breast, ovary and prostate, and mental disorders including schizophrenia and depression
"Poverty that lays eggs"Zimbabwe "…poverty passes from one generation to another, as if the offspring sucks it from the mother's breast" Uganda "90m children stunted…serious intergenerational effects" James Commission 2000
Status syndromeLow social status linked to high mortality • Shishehbor (JAMA 2006) • 30,000 patients with heart disease in Ohio, USA, 1990-2002 • Over 2000 deaths • People with low socio-economic status had abnormal heart rate recovery, death rate higher by 22-42% • Lack of control, low participation
Lifestyle (chronic) diseases: a few tough choices As lifespan increases, burden of ill health shifts to "chronic" diseases (CVD, cancer) though chronic diseases are rising in young people too, and infections have not disappeared There are "modifiable" risk factors, esp. for CVD, including diet, exercise and smoking but some risks are hard to change (addiction), or beyond personal control (society, long time scales) Chronic disease (esp. cancer) is linked to aging, through lifelong accumulation of faults no gain without pain, no quick-fix, no elixir for the "Fantastic Voyage"