# A doctor is reviewing the health records of two patients. Patient A is a 55-year-old male who exercises regularly, has a healthy body mass index (BMI), does not smoke, and has a blood cholesterol level of 4.2 mmol/L. Patient B is a 55-year-old male who does little exercise, is classified as obese, smokes 20 cigarettes a day, and has a blood cholesterol level of 7.8 mmol/L. Explain why Patient B has a higher risk of developing cardiovascular disease than Patient A.

> Pearson Edexcel A-Level Biology A (9BI0) — 1.1 Cardiovascular disease and risk · Explain · 5 marks

> A doctor is reviewing the health records of two patients. Patient A is a 55-year-old male who exercises regularly, has a healthy body mass index (BMI), does not smoke, and has a blood cholesterol level of 4.2 mmol/L. Patient B is a 55-year-old male who does little exercise, is classified as obese, smokes 20 cigarettes a day, and has a blood cholesterol level of 7.8 mmol/L.

## Mark scheme (5 marks)

1. Patient B has a higher blood cholesterol level, which increases the risk of fatty deposits (plaques/atheroma) forming in artery walls
2. These fatty deposits cause the artery lumen to narrow (arteries become narrowed), restricting blood flow
3. Smoking damages the lining of blood vessels / causes platelets to clump, increasing the risk of a blood clot (thrombosis) forming
4. Obesity / lack of exercise is linked to higher blood pressure, which puts greater strain on artery walls and increases risk of cardiovascular disease
5. Patient A's lower cholesterol, healthy weight, exercise and non-smoking status each reduce risk, so the combination of multiple risk factors in Patient B makes his overall risk significantly greater

## Key terms

- [cardiovascular disease](https://www.gradenine.co.uk/glossary/cardiovascular-disease)
- [cholesterol](https://www.gradenine.co.uk/glossary/cholesterol)

## Related

- [Revision notes for Pearson Edexcel A-Level Biology A (9BI0)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-doctor-is-reviewing-the-health-b1db2fdb) · Published by Druglandscape Ltd.