Figures from the National Diabetes Audit show that mortality rates are higher at the target guideline levels advised for people with diabetes by the NHS than at neighbouring higher cholesterol levels.
The data has particular implications for older people. Previous research, such as a study by Columbia University in 2005, has shown that people over 65 with the lowest cholesterol levels had twice the risk of mortality as over 65s with the highest levels.
The data from the National Diabetes Audit 2011-2012 shows the highest mortality rates at the lowest and highest cholesterol levels. The target total cholesterol level for people with diabetes is under 4 mmol/l and sits at a relatively low level.
The Audit shows that mortality rates are at their lowest between 4.0 and 6.0 mmol/l, with mortality rates are around 10% lower in this category than in the 3.0 to 4.0 mmol/l category. The Audit also shows that having very low cholesterol levels, below 3 mmol/l, is linked with even higher mortality than having high cholesterol levels above 6 mmol/l.
Whilst lower cholesterol levels earlier in life appear to have a protective effect, research indicates that the protective effect decreases the closer to old age people get. The data has significance as NICE is currently reviewing its draft recommendation on managing cholesterol (Lipid Modification), which would see a much greater number of people with diabetes offered statin treatment.