High cholesterol: Scottish data

Prevalence

The Scottish Health Survey measures the blood pressure of a sample of participants and collects information on whether the participants are taking lipid lowering medication to treat high cholesterol.  

Mean cholesterol

Mean total cholesterol of participants in the Scottish Health Survey is shown in Table 1. This information has been split by age group, gender and whether the participant is taking lipid lowering medication. 

Table 1: Mean total cholesterol (mmol/l), by age and sex, 1995, 1998, 2003 and 2008

	Including those taking lipid lowering medication								Excluding those taking lipid lowering medication
	Men				Women				Men				Women
Age	1995	1998	2003	2008	1995	1998	2003	2008	1995	1998	2003	2008	1995	1998	2003	2008
16 to 24 years	4.4	4.3	4.3	n/a	4.7	4.5	4.5	n/a	4.4	4.3	4.3	n/a	4.7	4.5	4.5	n/a
25 to 34 years	5.4	5.1	5.2	n/a	5.1	4.9	5.0	n/a	5.4	5.1	5.2	n/a	5.1	4.9	5.0	n/a
35 to 44 years	5.9	5.6	5.6	n/a	5.4	5.2	5.4	n/a	5.9	5.6	5.6	n/a	5.4	5.2	5.4	n/a
45 to 54 years	6.1	5.9	5.9	n/a	6.1	5.8	5.9	n/a	6.1	5.9	6.0	n/a	6.0	5.8	5.9	n/a
55 to 64 years	6.1	5.8	5.7	n/a	6.5	6.2	6.3	n/a	6.1	5.8	5.9	n/a	6.5	6.2	6.5	n/a
65 to 74 years	n/a	5.6	5.5	n/a	n/a	6.3	6.1	n/a	n/a	5.6	5.7	n/a	n/a	6.4	6.4	n/a
75+ years	n/a	n/a	5.1	n/a	n/a	n/a	6.0	n/a	n/a	n/a	5.3	n/a	n/a	n/a	6.2	n/a
16 to 64 years	5.6	5.4	5.4	5.2	5.6	5.3	5.5	5.3	5.6	5.4	5.4	5.2	5.6	5.3	5.5	5.3

Source: Scottish Health Survey.

Note: Unlike the 1995, 1998 and 2003 surveys, in 2008 only a sub-sample of adults in the main sample were eligible to take part in the Stage 2 nurse visit.  As a consequence results by age group for 2008 are unavailable due to small sample sizes.

These results suggest that the estimated average total cholesterol level for adults aged 16-64 years in Scotland is slightly above the current UK limit for 'raised cholesterol' (5.0 mmol/l), and is still fairly high compared to the 'optimum' level of 3.8 mmol/l.

Raised cholesterol

The current threshold used to determine 'raised' cholesterol in the UK is 5.0 mmol/l.  Previously the threshold was 6.5 mmol/l.  Table 2 shows the estimated percentage of the Scottish population above the current UK threshold for 'raised' cholesterol (5.0 mmol/l).  Table 3 shows the estimated percentage of the Scottish population above the previous threshold of 6.5 mmol/l.

Table 2: Percentage of the population with a raised cholesterol level (over 5.0 mmol/l),  by age and sex, 1995, 1998, 2003 and 2008

	Including those taking lipid lowering medication								Excluding those taking lipid lowering medication
	Men				Women				Men				Women
Age	1995	1998	2003	2008	1995	1998	2003	2008	1995	1998	2003	2008	1995	1998	2003	2008
16 to 24 years	26.4	22.4	21.7	n/a	34.3	24.8	26.2	n/a	26.4	22.4	21.7	n/a	34.3	24.8	26.2	n/a
25 to 34 years	65.3	53.3	58.7	n/a	53.7	43.5	46.4	n/a	65.2	53.2	58.5	n/a	53.7	43.5	46.4	n/a
35 to 44 years	81.4	69.2	71.5	n/a	68.4	57.7	65.3	n/a	81.2	69.1	71.3	n/a	68.4	57.7	65.0	n/a
45 to 54 years	86.9	80.9	82.6	n/a	86.5	78.7	83.0	n/a	86.9	81.0	83.1	n/a	86.5	78.6	82.7	n/a
55 to 64 years	86.1	76.1	75.4	n/a	92.0	88.6	88.2	n/a	85.8	78.5	83.1	n/a	92.0	89.4	91.7	n/a
65 to 74 years	n/a	71.7	67.1	n/a	n/a	91.4	84.3	n/a	n/a	74.0	76.9	n/a	n/a	93.8	89.8	n/a
75+ years	n/a	n/a	55.5	n/a	n/a	n/a	78.5	n/a	n/a	n/a	85.7	n/a	n/a	n/a	86.1	n/a
16 to 64 years	69.8	61.9	63.3	56.5	67.8	59.7	62.9	58.3	69.6	61.9	63.8	58.2	67.7	59.5	62.7	57.7

Source: Scottish Health Survey.

Note: Unlike the 1995, 1998 and 2003 surveys, in 2008 only a sub-sample of adults in the main sample were eligible to take part in the Stage 2 nurse visit.  As a consequence results by age group for 2008 are unavailable due to small sample sizes.

The data show that 56% of men and 58% of women (including those taking lipid lowering medication) aged 16-64 years had cholesterol levels above 5.0 mmol/l in 2008. Excluding those taking lipid lowering medication prevalence was around 58% for both men and women.  In general, the percentage with a raised cholesterol level increases with age. In more recent years there is a suggestion in the data that this pattern is changing for men, possibly as a result of screening and targeted treatment.

There appears to be a general downward trend in the percentage with a raised cholesterol level. However the pattern is not stable and there could be effects from random variation or the way the test is carried out. It must also be remembered that there was a much smaller sample size in the 2008 Scottish Health Survey than in previous years.

Table 3: Estimated percentage of the population (%) with a raised cholesterol level (over 6.5 mmol/l), by age and sex, 1995, 1998, 2003 and 2008

	Including those taking lipid lowering medication								Excluding those taking lipid lowering medication
	Men				Women				Men				Women
Age	1995	1998	2003	2008	1995	1998	2003	2008	1995	1998	2003	2008	1995	1998	2003	2008
16 to 24 years	1.3	2.0	1.7	n/a	4.3	3.0	3.0	n/a	1.3	2.0	1.7	n/a	4.3	3.0	3.0	n/a
25 to 34 years	15.0	6.7	12.1	n/a	8.1	4.2	8.2	n/a	14.9	6.7	12.2	n/a	8.1	4.2	8.2	n/a
35 to 44 years	30.5	21.9	19.8	n/a	14.9	7.1	12.8	n/a	30.1	22.0	20.1	n/a	14.9	7.0	12.3	n/a
45 to 54 years	35.0	26.8	29.0	n/a	31.9	23.5	28.3	n/a	34.9	27.4	29.7	n/a	31.8	23.5	28.6	n/a
55 to 64 years	32.7	23.2	24.0	n/a	50.9	37.3	43.3	n/a	32.2	23.9	29.1	n/a	50.7	38.6	47.9	n/a
65 to 74 years	n/a	16.8	19.9	n/a	n/a	40.4	39.2	n/a	n/a	18.1	25.7	n/a	n/a	43.3	47.3	n/a
75+ years	n/a	n/a	11.6	n/a	n/a	n/a	35.8	n/a	n/a	n/a	13.8	n/a	n/a	n/a	41.3	n/a
16 to 64 years	22.9	16.6	17.8	11.4	21.5	14.7	19.0	14.5	22.6	16.7	18.5	12.1	21.3	14.6	19.2	14.6

Source: Scottish Health Survey.

Note: Unlike the 1995, 1998 and 2003 surveys, in 2008 only a sub-sample of adults in the main sample were eligible to take part in the Stage 2 nurse visit.  As a consequence results by age group for 2008 are unavailable due to small sample sizes.

The data show that 11% of men and 14% of women (including those taking lipid lowering medication) aged 16-64 years had cholesterol levels above 6.5 mmol/l in 2008. Excluding those taking lipid lowering medication prevalence was around 12% for men and 15% for women.  In general, the percentage with a raised cholesterol level increases with age initially and then often decreases in older age bands.

There appears to be a general downward trend in the percentage of men with a raised cholesterol level but a less consistent pattern for women. There could be effects from random variation or the way the test is carried out. It must also be remembered that there was a much smaller sample size in the 2008 Scottish Health Survey than in previous years.

Primary care activity

Data on patients seen in primary care in Scotland in 2007/08 estimates that 1% of the population (almost 51,000 people) consulted a member of the general practice team at least once over the previous year because of a high cholesterol level (see first worksheet in High Cholesterol PTI 2007/08  (54KB)). These figures are likely to underestimate the population being treated for high cholesterol either on its own or because of high overall cardiovascular risk.

The Scottish Health Survey shows that an estimated 56% of men and 58% of women aged 16-64 years have a cholesterol level above 5.0 mmol/l. However, this data is not directly comparable with the practice team data as patients may have their cholesterol level measured of treated even when the main recorded reason for consultation is a different condition.

The above Excel file includes three worksheets with detailed practice team information estimates for high cholesterol: patients by gender and age; patients by gender and deprivation category; and contacts per patient by gender and deprivation category.

Mortality estimates

The World Health Organization has estimated that worldwide about 8% of all deaths are attributable to a 'non-optimal' cholesterol level (mean cholesterol over 3.8 mmol/l) (Lawes et al, 2004). Applying this percentage to Scotland would give an estimate of around 4,450 deaths per year attributable to raised cholesterol levels.