Influence of benzodiazepines on antiparkinsonian drug treatment in levodopa users

Pneumonia Risk Associated with the Use of Individual Benzodiazepines and Benzodiazepine Related Drugs among the Elderly with Parkinson's Disease

Most patients with Parkinson's disease (PD) gradually develop oropharyngeal dysphagia which is often associated with pneumonia risk. The possible association of benzodiazepine (BZD) and benzodiazepine related drugs (BZRD) use with pneumonia risk has received increasing attention but remains controversial. We investigated pneumonia risk associated with the use of BZDs and BZRDs in older adult patients with PD. This case-control study analyzed data of 551,975 older adult patients with PD between 2001 and 2018 in Taiwan. To minimize potential confounding, we used 1:4 propensity score matching to include older adult patients without pneumonia as controls. Incident pneumonia risk was significantly higher in current (adjusted odds ratio (aOR) = 1.25, 95% CI = 1.23-1.27) and past (aOR = 1.13, 95% CI = 1.11-1.15) users of BZDs. Regarding BZRDs, recent (aOR = 1.08, 95% CI = 1.06-1.11) and past (aOR = 0.89, 95% CI = 0.88-0.91) users had higher and lower risks of incident pneumonia, respectively. Pneumonia risk varied based on their use of BZDs and BZRDs. In these individuals, incident pneumonia risk was high in users of BZDs, such as midazolam, lorazepam, flunitrazepam, estazolam, and clonazepam. Regarding the use of BZRDs, zopiclone increased incident pneumonia risk.

Levodopa availability improves with progression of Parkinson’s disease

BACKGROUND

Previous pharmacokinetic trials with standard levodopa formulations showed a different behaviour of levodopa degradation in plasma of patients with Parkinson's disease (PD) in various stages.

OBJECTIVES

To investigate associations between levodopa plasma levels in relation to the scored intensity of PD.

SUBJECTS AND METHODS

We administered water soluble 100 mg levodopa and 25 mg benserazide to 50 PD patients, taken off medication for at least 12 hours, and assessed the levodopa plasma concentrations during an 180 minutes period under standardised conditions.

RESULTS

The computed area under the curve (AUC) values of levodopa plasma levels were significant higher in advanced PD patients. PD rating scores significantly correlated to the AUC outcomes and the maximum levodopa plasma concentration.

CONCLUSIONS

Levodopa availability improves with progression of PD. This may result from deteriorated peripheral activity of levodopa metabolising enzymes or an increasing enteric dysfunction with subsequent better duodenal levodopa absorption or both.

Chronic levodopa intake increases levodopa plasma bioavailability in patients with Parkinson's disease

Previous pharmacokinetic trials with standard levodopa formulations showed a different behavior of levodopa degradation in plasma of patients with Parkinson's disease (PD) in various advanced stages. The objective of this trial was to compare levodopa plasma metabolism in PD patients with and without previous long-term levodopa intake after oral intake of a dispensable levodopa/benserazide formulation (DLB). The over a 150 min interval computed area under the curve values of levodopa plasma levels after DLB administration were significantly (ANCOVA: F(1,19) = 7.88, P = 0.01) higher in PD patients with chronic levodopa treatment compared to patients without prior levodopa treatment. The maximum plasma levodopa concentration did not differ (ANCOVA: F(1.19) = 1.17, P = 0.29). Long-term levodopa administration results in an increased levodopa plasma bioavailability in PD patients.