Before starting

Required

• Baseline
  • ALT or AST
  • Blood pressure
  • Body mass index
  • HDL cholesterol (non fasting)
  • non-HDL cholesterol (non-fasting)
  • Serum creatinine (for creatinine clearance) or Estimated glomerular filtration rate
  • Thyroid stimulating hormone
  • Total cholesterol (non-fasting)
  • Triglycerides (non-fasting)

Consider

• Baseline
  • HbA1c or Blood glucose · If high risk of diabetes mellitus
  • Full blood count
  • Creatine kinase

When to measure creatine kinase

Consider for patients with any of:

• renal impairment
• hypothyroidism
• personal or familial history of hereditary muscular disorders
• previous history of unexplained muscle pain (whether associated or not with previous lipid-regulating drugs)
• previous history of liver disease or where substantial quantities of alcohol are consumed
• elderly (aged over 70 years)
• interactions with other medicines where plasma levels may be increased

Creatinine kinase and exercise

Do not measure following strenuous exercise or in the presence of any plausible alternative cause of an increase since value interpretation is difficult.

Consider specialist advice if baseline CK level extremely elevated (e.g. because of physical occupation or rigorous exercise).

Continued until stable

Required

• At 3 months
  • ALT or AST

High intensity statins

• At 3 months
  • HDL cholesterol (non fasting)
  • non-HDL cholesterol (non-fasting)
  • Total cholesterol (non-fasting)
  • Triglycerides (non-fasting)

Definition of high intensity statins

High intensity statins include:

• Atorvastatin at doses of or greater than 20mg daily
• Rosuvastatin at doses of or greater than 10mg daily
• Simvastatin at doses of 80mg daily

Consider

• At 3 months
  • Full blood count · ask patient if experiencing muscle symptoms first
  • HbA1c or Blood glucose · if high risk of diabetes mellitus
  • Creatine kinase

Ongoing once stable

Consider

• Annually
  • ALT or AST · repeat after first year only if indicated
  • Full blood count · ask patient if experiencing muscle symptoms first; if statin tolerated for greater than 3 months explore other causes
  • non-HDL cholesterol (non-fasting)

Abnormal results

Transaminases

Do not initiate statins or stop existing if ALT or AST are greater than 3 times upper limit of normal (ULN).

Creatine kinase

Do not initiate statins or stop existing if CK greater than 5 times upper limit of normal (ULN).

Re-measure after 7 days: if CK still greater than 5 times ULN do not re-start; if CK less than 5 times ULN, re-start statin at lower dose.

Renal impairment

If eGFR less than 30mL/min/1.73m² check dose with renal specialist.

Rosuvastatin in renal impairment

Rosuvastatin contra-indicated if CrCl less than 30mL/min; 40mg dose contraindicated if CrCl less than 60ml/min.

Hypothyroidism

Manage hypothyroidism adequately before starting a statin.

Rosuvastatin in hypothyroidism

Rosuvastatin 40mg is contraindicated in hypothyroidism.

Notes

Advice to patients

Advise patients to report any unexplained muscle pain.

Bibliography

• National Institute for Health and Care Excellence (NICE). Cardiovascular disease: risk assessment and reduction, including lipid modification [CG181]. Jul 2014 [updated Sep 2016; cited 12/02/2020]
• Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press [cited 30/06/2020]
• NICE Clinical Knowledge Summaries (CKS). Lipid modification – CVD prevention. Updated Aug 2019 [cited 01/09/2020]
• AstraZeneca UK Ltd. Summary of Product Characteristics – Crestor 40mg film-coated tablets. Last revised 07/2019 [cited 30/07/2020]
• The Association of Clinical Biochemistry, British Thyroid Association and British Thyroid Foundation. UK Guidelines for the Use of Thyroid Function Tests July 2006 [cited 30/07/2020]