Epidemiology of Peripheral Vascular Disease

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					Epidemiology of Peripheral
    Vascular Disease
            Sohail Ahmed

 School of Population and Health Sciences
• Peripheral vascular disease refers to a
  cluster of conditions in which narrowing
  and hardening of blood vessels occurs in
  the peripheral circulation, particularly in
  the legs. (modified from WHO definition)

• By far the commonest underlying
  pathology is Atherosclerosis.
Atherosclerosis
                           Risk Factors

Non-modifiable:                  Modifiable:
1. Age (mid & older)             1. High blood pressure
2. Male gender (upto age 65)     2. Diabetes
3. Family history of             3. Smoking (Buerger’s disease)
   hyperlipidaemia (1:500)
4. Race (e.g,African-Americans   4. Hyperlipidaemia
    OR=2.3) Criqui 2005.         5. Obesity
                                 6. Excessive alcohol
                                 7. Sedentary life
                                 8. Stress & depression
                                 9. Trauma
             Clinical Features

• Asymptomatic
• Intermittent
  claudication
• Rest pain / critical
  ischaemia
• Ulcers / sepsis
• Gangrene
            Asymptomatic
• Identified through random testing of
  population for research.

• Testing ABI in patients with other
  cardiovascular disease. (ABI<0.9)
          Intermittent Claudication
• Pain in the legs on walking a
  certain distance.

• Associated cardiovascular
  morbidity

• Disability (social
  consequences)

• Dependence on medicines.

• May require surgery

• 15% require amputation
  within 1 year (Martson 2006)
              Critical Ischaemia
• Rest pain (ABI<0.5)

• Sleeplessness (Severe disability)

• Hospitalization

• 34% require amputation within 1 year (Martson 2006)

• Acute on chronic episode leading to limb loss or
  death.
                            Ulcers
• 500,000 with recurrent leg
  ulcers in UK (10% arterial)

• Disability

• Sepsis

• Frequent hospitalzation

• Surgical procedures

• Amputation

• Death
                   Gangrene
• Amputation

• High risk of mortality
  due to associated CVD.

• Mortality 20%(1 yr), 40-
  70%(5yr), 80-95%(10yr).

• Burden on resources
               Epidemiological Data
• Prevalence 7% to 15% in the     • Amputation rate within one
  middle aged and the               year of diagnosis is 10-
  elderly(Cuschieri 2002)
                                    40%(Dormandy 1999)

• 20% in over 75(Hiatt 1995)      • Mortality after amputation:
                                    1 year = 20%
• Coronary artery disease
  coexist in 68% & Stroke           5 years = 40% - 70%
  coexist in 42% (Ness & Aronow     10 years = 80% - 95%
  1999)


• Classified alongwith other      • Second most common
  cardiovascular diseases it is     cause of disability in the UK
  the commonest cause of            (WHO)
  mortality in UK. (Males
  300/100,000/yr, and Females
  190/100,000/yr)                 • Prevalent in deprived areas
                                   Worldwide Distribution
  Exclusive studies on PVD were only conducted in USA & Europe but its
  prevalence can be directly translated from cardiovascular mortality data
                             from WHO (2005)

                                                                           Nigeria

                 Mortality due to CVD & diabetes (all ages)               Pakistan
                                 WHO 2005.
           CVD         D.M       Estim. Loss of national income in 2005      India
Nigeria    11%         1%        $ 400 m
                                                                           France
Pakistan   22%         1%        $1b
India      28%         2%        $9b                                        China
                                                                                                             CVD

France     31%         2%        $?                                                                          D.M

China      33%         1%        $ 18 b                                    Canada
Canada     34%         3%        $ 500 m
                                                                               UK
U.K        38%         1%        $2b
USA        38%         3%        $?                                           USA
Russia     61%         0%        $ 11 b
                                                                           Russia

                                                                                     0   20   40   60   80
Distribution of Obesity
   International Smoking Trends
• Although high across the
  world, it is inversely         Nigeria
  proportional to affluence.    Pakistan

                                   India
• Number of deaths due to
  tobacco is equal in all        France
  countries but the burden of     China                       fem ales
  disease is much higher in
                                                              m ales
  developing countries.          Canada

                                     UK
• Buerger’s disease is only
                                    USA
  prevalent in Mediterranean,
  Eastern European and some      Russia
  Oriental countries.
                                           0   20   40   60
     Modifiable Risk Factors for UK
               Population
•   Hypertension
•   Smoking
•   Excessive alcohol consumption
•   Obesity & hyperlipidaemia
•   Diabetes mellitus
•   Physical inactivity
•   Factors associated with Ethnicity
                   Hypertension
• 20% of 16+ were                • Risk factors other
  hypertensive in 1998.
                                   than ageing
• 80/1000 people in Eng &
  Wales.
                                   Obesity.
• Prevalence increasing (only
  1/4th due to ageing).HSE         Smoking.
                                   Lack of exercise.
• 17% higher in females (after
  correcting for age)              Excess of alcohol.
• Twice as likely to die from      Excessive salt
  CVA or CAD.
                                   intake.
• Over 100,000 in Eng & Wales      Diabetes mellitus.
  suffer a first stroke every
  year.
                   Smoking
• Males 23%
  Females 21% (ONS
  2006)

• Trend decreasing since
  1974.

• Strongly related to
  socio-economic class.

• Marked differences
  among different ethnic
  groups.
               Excessive Drinking
• Recommended daily
  benchmark – no more than 4
  units for men & 3 units for
  women.

• Heavy drinking – 8 units for
  men & 6 units for women (at
  least one day during a
  week).

• Heavy drinkers
  Males 32%
  Females 24%

• %age of people exceeding
  daily limit
     Drinking in ethnic groups
• Adults drinking above
  the daily
  recommended limit by
  ethnic group and sex.
     Obesity & Physical Activity
• Obesity in England
  2002
  Children 17%
  Adults 23%

• Increasing markedly

• No evidence to suggest
  any increase in caloric
  intake. (other factors?)

• Physical activity
  decreasing since early
  1990s.
                     Diabetes mellitus
•   1.15 million with diabetes in
    Eng & Wales in 1998.

•   From 1994 to 1998 there was
    18% rise in prevalence in males
    and 20% rise in females.

•   Prevalence higher in males.

•   Account for 9% of annual
    hospital expenditure.

•   Mortality significantly higher in
    diabetics.

•   Mortality higher in lower socio-
    economic areas.

•   More obese, diabetic patients in
    deprived areas.
                    Comments
• CAD is particularly prevalent in asians and stroke is
  prevalent in afro-carribeans. There is a need for better
  studies on assessing PVD/CVD in these groups.

• Early diagnosis of asymptomatic, high risk population is
  needed to prevent symptoms and reduce the burden of
  the disease.

• Need for increasing awareness among general public
  about the consequences of their lifestyles.

• Need for more extensive studies on PVD around the
  world to get a better understanding of the disease.
Thank you