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: 1.Age (mid & older) 2.Male gender (upto age 65) 3.Family history of hyperlipidaemia (1:500) 4.Race (e.g,African-Americans OR=2.3) Criqui Modifiable: 1.High blood pressure 2.Diabetes 3.Smoking (Buerger’s disease) 4.Hyperlipidaemia 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), %(5yr), 80-95%(10yr). Burden on resources

Epidemiological Data Prevalence 7% to 15% in the middle aged and the elderly (Cuschieri 2002) 20% in over 75 (Hiatt 1995) Coronary artery disease coexist in 68% & Stroke coexist in 42% (Ness & Aronow 1999) Classified alongwith other cardiovascular diseases it is the commonest cause of mortality in UK. (Males 300/100,000/yr, and Females 190/100,000/yr) Amputation rate within one year of diagnosis is % (Dormandy 1999) Mortality after amputation: 1 year = 20% 5 years = 40% - 70% 10 years = 80% - 95% Second most common cause of disability in the UK (WHO) 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)

Distribution of Obesity

International Smoking Trends Although high across the world, it is inversely proportional to affluence. Number of deaths due to tobacco is equal in all countries but the burden of disease is much higher in developing countries. Buerger’s disease is only prevalent in Mediterranean, Eastern European and some Oriental countries.

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 hypertensive in /1000 people in Eng & Wales. Prevalence increasing (only 1/4 th due to ageing).HSE 17% higher in females (after correcting for age) Twice as likely to die from CVA or CAD. Over 100,000 in Eng & Wales suffer a first stroke every year. Risk factors other than ageing Obesity. Smoking. Lack of exercise. Excess of alcohol. Excessive salt intake. Diabetes mellitus.

Smoking Males 23% Females 21% (ONS 2006) Trend decreasing since 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 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.

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