Impulsive-compulsive behaviors in parkin-associated Parkinson disease

Another slow week updating the blog... but this is important work. Really interesting to see that the ICB predated the diagnosis of PD in a number of the cases. As well has further characterising parkin clinical features, I think this has the potential to tell us more about the pathological substrate of ICBs given that parkin cases tend to have restricted pathology compared with idiopathic PD...

Neurology. 2016 Sep 2. pii: 10.1212/WNL.0000000000003177. [Epub ahead of print]

Morgante F, Fasano A, Ginevrino M, Petrucci S, Ricciardi L, Bove F, Criscuolo C, Moccia M, De Rosa A, Sorbera C, Bentivoglio AR, Barone P, De Michele G, Pellecchia MT, Valente EM.

OBJECTIVE:

The aim of this multicenter, case-control study was to investigate the prevalence and severity of impulsive-compulsive behaviors (ICBs) in a cohort of patients with parkin-associated Parkinson disease (PD) compared to a group of patients without the mutation.

METHODS:

We compared 22 patients with biallelic parkin mutations (parkin-PD) and 26 patients negative for parkin, PINK1, DJ-1, and GBA mutations (PD-NM), matched for age at onset, disease duration, levodopa, and dopamine agonist equivalent daily dose. A semistructured interview was used to diagnose each of the following ICBs: compulsive sexual behavior, compulsive buying, binge eating, punding, hobbyism, and compulsive medication use. The Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease-Rating Scale (QUIP-RS) was adopted to rate ICB severity.

RESULTS:

Frequency of patients with at least one ICB was comparable between parkin-PD and PD-NM. Nevertheless, when analyzing the distribution of specific ICBs, a higher frequency of compulsive shopping, binge eating, and punding/hobbyism was found in the parkin-PD group. Compared to PD-NM, parkin-PD patients with ICB had younger onset age and higher frequency of smokers; in 5 patients, ICB had predated PD onset. Total and partial (compulsive buying, compulsive sexual behavior, binge eating, hobbyism/punding) QUIP-RS scores were higher in patients with parkin-PD compared to patients with PD-NM. Logistic regression analysis showed that the presence of parkin mutations was associated with smoking status and higher QUIP-RS total score.

CONCLUSIONS:

Our data expand the parkin-associated phenotypic spectrum demonstrating higher frequency and severity of specific ICBs, and suggesting an association between the parkin genotype, smoking status, and ICB severity.