Association between inherited CYP2D6/2C19 phenotypes and anticholinergic measures in elderly patients using anticholinergic drugs

Anticholinergic Medication and Caries Status Predict Xerostomia under 65

The use of anticholinergic medications is increasing in younger ages, yet information about xerostomia, the most common anticholinergic side effect, is limited. This case–control retrospective study examines the relationship between anticholinergic medication-induced xerostomia and caries status among adults between 18 and 65 years of age. The study sample comprised 649 cases with xerostomia and 649 age- and gender-matched controls. The anticholinergic burden was estimated using the anticholinergic drug scale (ADS). Caries experience was recorded by calculating the Decayed, Missing, Filled Tooth (DMFT) index. Individuals with xerostomia had a higher mean DMFT index (16.02 ± 9.50), which corresponded with a higher level of anticholinergic exposure from medications (3.26 ± 2.81) compared to their age and gender-matched controls without xerostomia (13.83 + 8.83 and 1.89 ± 2.45, respectively). Logistic regression analysis verified the effects of DMFT, the total number of AC medications, and the ADS burden on xerostomia status. Comparing adults with or without xerostomia revealed statistical differences in several risk factors, such as smoking, diabetes, sleep apnea, and the utilization of anticholinergic medications. A personalized dental care plan should include the evaluation of the anticholinergic burden from medications regardless of the patient’s age to prevent increased caries severity.

Delirium secondary to anticholinergics

We present a case of a young man who developed sudden deterioration in his physical and mental state whilst being treated as an inpatient for substance-induced psychosis. This deterioration was manifested by sudden disorientation, change in behaviour and visual hallucinations. It was only after excluding other potential causes that this presentation was attributed to the regular administration of procyclidine that was being used to counteract the extrapyramidal side effects from antipsychotics. The patient showed a dramatic improvement on stopping procyclidine. This case highlights the importance of awareness of rare adverse drug reactions and the resultant distressing effect for the patient himself.

Anticholinergic medication: Related dry mouth and effects on the salivary glands

OBJECTIVE

Salivary glands are among the most sensitive target organs of medications with anticholinergic (AC) properties, interrupting the neural stimulation of saliva secretion and reducing saliva flow. Hyposalivation results in dry mouth, leading to dental caries, intraoral infection, orofacial pain, problems with speaking and swallowing, and diminished oral health--related quality of life. Current understanding of the pharmacokinetics of AC medications and their effect on muscarinic receptors in the salivary glands were reviewed to assist clinicians in predicting salivary damage in patients with AC medication-induced dry mouth.

STUDY DESIGN

We summarized the literature related to the mechanisms and properties of AC medications, anticholinergic adverse effects, and their effect on salivary function and management strategies to prevent oral health damage.

RESULTS

Although a large number of studies reported on the frequencies of medication-induced dry mouth, we found very limited data on predicting individual susceptibility to AC medication--caused hyposalivation and no prospective clinical studies addressing this issue.

CONCLUSION

Dry mouth is most frequently caused by medications with AC properties, which interrupt the neural stimulation of saliva secretion. Interdisciplinary care should guide pharmacotherapeutics and dental interventions should aim in preventing AC salivary adverse effects and reducing the oral health burden from AC medication-induced dry mouth.

The role of sex, age and genetic polymorphisms of CYP enzymes on the pharmacokinetics of anticholinergic drugs

There is evidence that use of drugs with anticholinergic properties increases the risk of cognitive impairment, and increased exposure to these drugs potentiates this risk. Anticholinergic drugs are commonly used even with associated risk of adverse events. Aging, sex, and genetic polymorphisms of cytochrome P450 (CYP) enzymes are associated with alterations in pharmacokinetic processes, which increase drug exposure and may further increase the risk of adverse drug events. Due to the increasing burden of cognitive impairment in our aging population and the future of personalized medicine, the objective of this review was to provide a critical clinical perspective on age, sex, and CYP genetic polymorphisms and their role in the metabolism and exposure to anticholinergic drugs. Age-related changes that may increase anticholinergic drug exposure include pseudocapillarization of liver sinusoidal endothelial cells, an approximate 3.5% decline in CYP content for each decade of life, and a reduction in kidney function. Sex-related differences that may be influenced by anticholinergic drug exposure include women having delayed gastric and colonic emptying, higher gastric pH, reduced catechol-O-methyl transferase activity, reduced glucuronidation, and reduced renal clearance and men having larger stomachs which may affect medication absorption. The overlay of poor metabolism phenotypes for CYP2D6 and CYP2C19 may further modify anticholinergic drug exposure in a significant proportion of the population. These factors help explain findings of clinical trials that show older adults and specifically older women achieve higher plasma concentrations of anticholinergic drugs and that poor metabolizers of CYP2D6 experience increased drug exposure. Despite this knowledge neither age, sex nor CYP phenotype are routinely considered when making decisions about the use or dosing of anticholinergic medications. Future study of anticholinergic medication needs to account for age, sex and CYP polymorphisms so that we may better approach personalized medicine for optimal outcomes and avoidance of medication-related cognitive impairment.

Frequency of CYP450 enzyme gene polymorphisms in the Greek population: review of the literature, original findings and clinical significance

The cytochrome P450 (CYP450) enzyme family is involved in the oxidative metabolism of many therapeutic drugs and various endogenous substrates. These enzymes are highly polymorphic. Prevalence of CYP450 enzyme gene polymorphisms vary among different populations and substantial inter- and intra-ethnic variability in frequency of CYP450 enzyme gene polymorphisms has been reported. This paper provides an overview and investigation of CYP450 genotypic and phenotypic reports published in the Greek population.