Lipoproteins are mixtures of fats and proteins, made in the liver, and they are used to transport fats around the body.

WHAT IS LIPOPROTEIN (a)/ Lp(a)?

Lipoprotein (a), or Lp(a) is an low density lipoprotein (LDL) with an apolipoprotein (a), [apo (a)] tail bonded to it.

LDL is sometimes called bad cholesterol but this is a matter for a different post - how it behaves varies! Lipids are complicated.

The apo(a) tail on the LDL particle - Lp(a) - makes it more sticky, or prone to attach and be taken into the blood vessel wall. where it can contribute to narrowing by forming cholesterol plaques (athersclerosis) and inflammation at that site, the inflammation making these plaques prone to rupture, causing heart attacks and/ or stroke.

SHOULD I HAVE MY Lp(a) MEASURED?

Lp(a) should be measured:

• those who have had any cardiovascular disease (CVD), or any member of the family (1st and 2nd degree relatives) has had before 60 years of age. A first degree relative is a sibling, child or parent. A second degree relative is grandparents, grandchildren, aunts, uncles and 1st cousins)

• First degree relatives of those with raised Lp(a) levels (>250nmol/L)

• familial hypercholesterolaemia (FH) or other inherited lipid conditions

• calcific aortic valve disease (or a family history)

• a borderline increased (but <15%) 10 year risk of CVD.

I recommend patients have their Lp(a) measured if they have been specifically recommended, or referred because of a lipid abnormality.

HOW DOES Lp(a) AFFECT ME?

There is a relationship between Lp(a) and risk of heart attack and stroke, the higher the level of Lp(a) the higher the risk of, and occurence of heart attack and stroke. Lp(a) also contributes to calcific aortic stenosis, the narrowing of the valve as blood leaves the left ventricle.

WHAT IS THE TREATMENT?

There is no treatment to lower Lp(a) that is proven to reduce it AND reduce the harm from it; those studies are being conducted, but until they report their results we assume nothing.

We already have effective ways to reduce cardiovascular risk, the risk of heart attack and stroke, many or most of them are familiar to us all. As one reads down one starts to see consistent themes:

• Stop smoking tobacco

• Avoid/ treat high blood pressure this includes: - diagnosing the cause of hypertension accurately, and having the most effective treatment for it, - reducing sodium in the diet, this is in table salt and/or used in the preparation and storage of processed food, - increasing potassium in the diet; fresh fruits and vegetables - increasing physical activity - stopping smoking

• Reduce LDL cholesterol concentrations and increase HDL cholesterol concentrations - there are dietary measures for this, reducing land animal fat in the diet, and increasing the proportion of fruit, vegetables and fibre, and it can include increasing fats from sea food

• Avoid diabetes and if one has diabetes, control the blood glucose effectively - this is obviously a whole topic in iteself

• If one is overweight or obese, reduce ones weight, particularly reduce waist circumference, abdominal and visceral fat (fat stored around and in the organs where one cannot necessarily see it). - there are proven dietary modifications to reduce weight - there are proven medications that can help lose weight safely

• Reduce the fat in the diet from land animals, and necessarily increase the proportion of fat from vegetables and plant matter, and possibly increase fats from sea-food, e.g. eat oily fish twice weekly. Consider Recipes that are Good For Your Heart and eat less foods that might raise cholesterol - the pages are provided from the British Heart Foundation

• If you drink alcohol, do so in moderation and always less than 14 units per week

The list is not exhaustive. However for those patients with high Lp(a), if their risk of cardiovascular disease is high, it can be even more important to do what one can across ones health, to reduce the risk. For many patients this can include taking a tablet to reduce LDL cholesterol (LDLc), but equally it can include taking a blood pressure tablet, stopping smoking, losing weight etc.

With the proven benefit of statins to reduce heart attacks and strokes, this is my broad, personal guide to considering Lp(a) for my patients. It is not fixed in stone, but helps me, the patient and their GP focus on improving things.

If Lp(a) is 75 - 199 nmol/L:

Address all modifiable CVD risk factors, including healthy lifestyle advice (4). • In patients with a QRISK3 of less than 5%, offer lifestyle advice and suggest a lipid profile and CVD risk assessment in 5 years. • In patients with a QRISK3 of 5 to 10% offer high intensity statin to treat to primary prevention target, i.e. 40% reduction in non-HDL-cholesterol. This recognises the additional risk factor that raised Lp(a) contributes to CVD risk. • In patients with a QRISK3 of > 10%, treat to secondary prevention target, i.e. LDL-cholesterol less than 1.8 mmol/L (or nonHDL-cholesterol less than 2.5 mmol/L

If Lp(a) is equal to or greter than 200 nmol/L

Offer high intensity statin and up-titrate or add ezetimibe as necessary. • If QRISK3 is less than 5%, consider only treating to primary prevention target. • In all other patients, aim for secondary prevention target. • Add PCSK9 inhibitor if indicated (in accordance with NICE TA393/394/733). • Recommend Lp(a) testing of first degree relatives and referral to Lipid Clinic if relatives Lp(a) is greater than 250 nmol/L.

I make every effort for accuracy. This post is the personal view of Dr Philip Kelly and does not represent personal medical advice for any patient. If you would like to comment on the post please do make contact.

If you have a clinical question about your own Lp(a) then Dr Philip Kelly or Professor Martin Whyte would be happy to see you.

If you have a reason to check your own Lp(a) most GP practices cannot request it. Your GP might support a referral to an NHS Lipid Clinic - though you would have to meet the criteria for this, or you can be referred to a doctor with an interest in lipids like Dr Kelly or Professor Whyte, finally you can check your Lp(a) using a home finger prick testing kit, for instance with Medichecks. If you go via this link you can put 'LSM' as a discount code at checkout, you will receive a 10% discount and the Practice will receive a 10% referral fee.