Many patients requiring statin
therapy have conditions which predispose them to peripheral neuropathy,
particularly diabetes mellitus and chronic renal
failure.2 Thus the observation of an association is not
necessarily indicative of causation. However, recovery on withdrawal of the
statin was noted in approximately half of the ADRAC cases (see Table), including
cases where the patient also had diabetes, and some reports describe positive
rechallenge. In two cases, symptoms developed after an increase in dose.
Statin-associated peripheral
neuropathy may persist for months or years after withdrawal of the statin.2,3
In two ADRAC cases of persistent peripheral neuropathy, motor and sensory
conduction tests showed minimal recovery 4 and 12 months, respectively, after
discontinuation of simvastatin, despite clinical improvement.3 A
further 21 cases had not recovered at the time of reporting, between one and
eight months after discontinuation of the statin. In two other reports, the
problem was persisting after 3 and 5 years, respectively.
The incidence of statin-induced
peripheral neuropathy appears to be low. A study, which excluded patients with
predisposing disease, attributed 4.5 cases per 10,000 person-years to statin
use.4
Consideration should be given to
drug withdrawal if patients taking a statin develop sensory or motor
disturbances.
References
1.
Paraesthesia and neuropathy with hypolipidaemic agents. Aust
Adv Drug Reactions Bull 1993; 12:2
2.
Chong PH, Boskovich A, Stevkovic N, Bartt RE. Statin-associated
peripheral neuropathy: review of the literature. Pharmacotherapy
2004;24:1194-1203
3.
Phan T, McLeod JG, Pollard JD, Peiris O, Rohan A, Halperm J-P. Peripheral
neuropathy associated with simvastatin. J Neurol
Neurosurg Psychiatry 1995;58:625-8.
4.
Gaist D, Jeppesen U, Andersen M, Garcia Rodriguez LA, et al. Statins and
risk of polyneuropathy: a case-control study. Neurology
2002;58:1333-7.
