Inception and deprescribing of statins in people aged over 80 years: cohort study.

Objective: statin use over the age of 80 years is weakly evidence-based. This study aimed to estimate rates of statin inception and deprescribing by frailty level in people aged 80 years or older.

Methods: a cohort of 212,566 participants aged ≥80 years was sampled from the UK Clinical Practice Research Datalink. Statin inception was defined as a first-ever prescription in a non-statin user; deprescribing was defined as a last ever statin prescription more than 6 months before the end of participant records. Rates were estimated in a time-to-event framework allowing for mortality as a competing risk. Co-variates were age, gender, frailty category and prevention type.

Results: prevalent statin use increased from 2001-5 (9.9%) to 2011-15 (49.3%). Inception of statins in never-users was low overall at 2.4% per year (95% confidence interval (CI) 2.2-2.6%) and declined with age. Deprescribing of statins in current users occurred at a rate of 5.6% (95% CI 5.4-5.9%) per year overall and increased with age, reaching 17.8% per year (95% CI 6.7-28.9%) among centenarians. Deprescribing was slightly higher for primary prevention (6.5% per year) than secondary prevention (5.2% per year) indications (P < 0.001). Deprescribing increased with frailty level being 5.0% per year in 'fit' participants and 7.1% in 'severe' frailty (P < 0.001).

Conclusions: statin use has increased in the over 80s but deprescribing is common and increases with age and frailty level. These paradoxical findings highlight a need for better evidence to inform statin use and discontinuation for people aged ≥80 years.