Association between Anticholinergic Burden and Constipation: A Systematic Review

The human colon: Evidence for degenerative changes during aging and the physiological consequences

BACKGROUND

The incidence of constipation increases among the elderly (>65 years), while abdominal pain decreases. Causes include changes in lifestyle (e.g., diet and reduced exercise), disease and medications affecting gastrointestinal functions. Degenerative changes may also occur within the colo-rectum. However, most evidence is from rodents, animals with relatively high rates of metabolism and accelerated aging, with considerable variation in time course. In humans, cellular and non-cellular changes in the aging intestine are poorly investigated.

PURPOSE

To examine all available studies which reported the effects of aging on cellular and tissue functions of human isolated colon, noting the region studied, sex and age of tissue donors and study size. The focus on human colon reflects the ability to access full-thickness tissue over a wide age range, compared with other gastrointestinal regions. Details are important because of natural human variability. We found age-related changes within the muscle, in the enteric and nociceptor innervation, and in the submucosa. Some involve all regions of colon, but the ascending colon appears more vulnerable. Changes can be cell- and sublayer-dependent. Mechanisms are unclear but may include development of "senescent-like" and associated inflammaging, perhaps associated with increased mucosal permeability to harmful luminal contents. In summary, reduced nociceptor innervation can explain diminished abdominal pain among the elderly. Degenerative changes within the colon wall may have little impact on symptoms and colonic functions, because of high "functional reserve," but are likely to facilitate the development of constipation during age-related challenges (e.g., lifestyle, disease, and medications), now operating against a reduced functional reserve.

Anticholinergic action is rarely a good thing

The evidence for the risks associated with anticholinergic agents has grown considerably in the last two decades. Not only are they associated with causing peripheral side effects such as dry mouth, blurred vision and constipation, but they can also cause central effects such as cognitive impairment; and more recently, they have consistently been linked with an increased risk of dementia and death in older people. This paper reviews the evidence for the associations of anticholinergic agents and the risk of dementia and increased mortality in dementia.

Poo Matters! A scoping review of impact of constipation on epilepsy

BACKGROUND

Epilepsy is a common neurological disorder which frequently presents with co-morbid physical health conditions, including constipation. However, the nature of the relationship between the two conditions has not been well defined.

AIM

To quantify constipation's relationship with epilepsy and anti-seizure medication (ASM).

METHOD

A scoping review registered on PROSPERO (CRD42022320079) with suitable search terms was conducted and reported in accordance with PRISMA guidance. CINAHL, Embase, PsycInfo and MEDLINE electronic databases were searched by an information specialist. The Joanna Briggs Institute (JBI) critical appraisal tools alongside the Oxford Centre for Evidence Based Medicine (OCEBM) levels of evidence were used to assist in assessing relevance, quality, and results of the included publications.

RESULTS

Nine articles selected for inclusion in the review. The prevalence of irritable bowel syndrome (including constipation) was reported to be up to five times more frequent in people with epilepsy (PWE). Functional constipation was reported in 36% of PWE. Constipation was found to be the second most common co-morbid condition in children with epilepsy. Two studies found constipation to precede seizures. Constipation was reported as a common side effect of ASMs in PWE. Two studies rated OCEBM level 2 the remaining level 3.

CONCLUSION

Our findings suggest a higher prevalence of constipation in PWE. Co-occurring multimorbidity and resulting polypharmacy adds further complexity to the process of establishing aetiology of constipation in PWE. Potential contributory aetiological factors for constipation such as neurodevelopmental and genetic disorders, ASM side effects and the epilepsy itself require better understanding and research.

Efficacy and safety of probiotics in Parkinson's constipation: A systematic review and meta-analysis

Background: Parkinson's disease (PD) is the most common neurodegenerative disease closely related to the immune system, among whose prodromes constipation is a representative symptom. Recent Randomized Controlled Trials (RCTs) have proved that probiotics can be used to effectively treat PD constipation, but the results are inconsistent. We performed a meta-analysis to assess the efficacy and safety of probiotic therapy on Parkinson's constipation. Methods: Questions about the research focus were constructed based on the Participants, Intervention, Comparison and Outcomes (PICO) Criteria. We searched electronic databases such as PubMed, Web of Science, EMBASE, Scopus, EBSCO, Cochrane and Google Scholar until March 2022 for eligible literatures. Our primary endpoints were stool frequency, stool consistency, the number of laxatives uses, UPDRS-III scores and adverse events. Results: 12 eligible studies (n = 818 patients) met the inclusion and endpoint criteria. Meta-analysis results showed that constipation symptoms were improved after probiotic treatment, including an increased stool frequency (WMD = 0.94, 95% CI:0.53 to 1.34; OR = 3.22, 95% CI:1.97-5.29), an improved stool consistency (WMD = 1.46, 95% CI:0.54-2.37), a reduced use of laxatives (WMD = -0.72, 95%CI: -1.04 to-0.41), and also a reduced Parkinson's UPDRS-III score (WMD = -6.58, 95%CI: -12.02 to -1.14); there was no significant difference in total adverse events (OR = 0.82, 95%CI:0.39-1.72). Conclusion: Our analysis suggests that probiotics can be used to improve the constipation and motor symptoms for patients with Parkinson's constipation, possibly by reducing the inflammatory response and improving gut-brain axis neuron function, whose safety also proved to be good.

Prescribing Trends for the Same Patients with Schizophrenia Over 20 Years

Background

Recent pharmacoepidemiology data show an increase in the proportion of patients receiving second-generation antipsychotic (SGA) monotherapy, but no studies have analyzed the same patients over a long period of time. Therefore, in this study, we retrospectively evaluated schizophrenia patients with available data for 20 years to determine whether the drug treatments in the same patients have changed in the past 20 years.

Methods

The study began in April 2021 and was conducted in 15 psychiatric hospitals in Japan. Schizophrenia patients treated in the same hospital for 20 years were retrospectively examined for all prescriptions in 2016, 2011, 2006, and 2001 (ie, every 5 years).

Results

The mean age of the 716 patients surveyed in 2021 was 61.7 years, with 49.0% being female. The rate of antipsychotic monotherapy use showed a slight increasing trend over the past 20 years; the rate of SGA use showed a marked increasing trend from 28.9% to 70.3% over the past 20 years, while the rate of SGA monotherapy use showed a gradual increasing trend over the past 20 years. The rates of concomitant use of anticholinergics, antidepressants, anxiolytics/sleep medications, and mood stabilizers showed decreasing, flat, flat, and flat trends over the past 20 years, respectively.

Conclusion

The results of this study showed a slow but steady substitution of SGAs for first-generation antipsychotics (FGAs) over time, even in the same patients.

Pharmacotherapy and the Role of Pharmacists in Rehabilitation Medicine

Pharmacotherapy is important in older patients undergoing rehabilitation because such patients, especially those with frailty and physical disabilities, are susceptible to drug-related functional impairment. Drug-related problems include polypharmacy, potentially inappropriate medications (PIMs), and potential prescription omissions. These problems are associated with adverse drug events such as dysphagia, depression, drowsiness, falls and fractures, incontinence, decreased appetite, and Parkinson's syndrome, leading to impaired improvement in activities of daily living (ADL), quality of life (QOL), and nutritional status. Moreover, the anticholinergic burden is associated with impaired physical and cognitive functions. Therefore, pharmacist-centered multidisciplinary pharmacotherapy should be performed to maximize rehabilitation outcomes. Pharmacotherapy includes a review of all medications, the assessment of drug-related problems, goal setting, correction of polypharmacy and PIMs, monitoring of drug prescriptions, and reassessment of drug-related problems. The goal of pharmacotherapy in rehabilitation medicine is to optimize drug prescribing and to maximize the improvement of ADL and QOL as patient outcomes. The role of pharmacists during rehabilitation is to treat patients as part of multidisciplinary teams and as key members of nutritional support teams. In this review, we aim to highlight existing evidence regarding pharmacotherapy in older adults, including drug-related functional impairment and the association between pharmacotherapy and functional, cognitive, and nutritional outcomes among patients undergoing rehabilitation. In addition, we highlight the important role of pharmacists in maximizing improvements in rehabilitation outcomes and minimizing drug-related adverse effects.

Inhibition of TRPC4 channel activity in colonic myocytes by tricyclic antidepressants disrupts colonic motility causing constipation

Tricyclic antidepressants (TCAs) have been used to treat depression and were recently approved for treating irritable bowel syndrome (IBS) patients with severe or refractory IBS symptoms. However, the molecular mechanism of TCA action in the gastrointestinal (GI) tract remains poorly understood. Transient receptor potential channel canonical type 4 (TRPC4), which is a Ca²⁺‐permeable nonselective cation channel, is a critical regulator of GI excitability. Herein, we investigated whether TCA modulates TRPC4 channel activity and which mechanism in colonic myocytes consequently causes constipation. To prove the clinical benefit in patients with diarrhoea caused by TCA treatment, we performed mechanical tension recording of repetitive motor pattern (RMP) in segment, electric field stimulation (EFS)‐induced and spontaneous contractions in isolated muscle strips. From these recordings, we observed that all TCA compounds significantly inhibited contractions of colonic motility in human. To determine the contribution of TRPC4 to colonic motility, we measured the electrical activity of heterologous or endogenous TRPC4 by TCAs using the patch clamp technique in HEK293 cells and murine colonic myocytes. In TRPC4‐overexpressed HEK cells, we observed TCA‐evoked direct inhibition of TRPC4. Compared with TRPC4‐knockout mice, we identified that muscarinic cationic current (mI_cat) was suppressed through TRPC4 inhibition by TCA in isolated murine colonic myocytes. Collectively, we suggest that TCA action is responsible for the inhibition of TRPC4 channels in colonic myocytes, ultimately causing constipation. These findings provide clinical insights into abnormal intestinal motility and medical interventions aimed at IBS therapy.

Gastrointestinal Dysfunction in Parkinson’s Disease: Current and Potential Therapeutics

Abnormalities in the gastrointestinal (GI) tract of Parkinson’s disease (PD) sufferers were first reported over 200 years ago; however, the extent and role of GI dysfunction in PD disease progression is still unknown. GI dysfunctions, including dysphagia, gastroparesis, and constipation, are amongst the most prevalent non-motor symptoms in PD. These symptoms not only impact patient quality of life, but also complicate disease management. Conventional treatment pathways for GI dysfunctions (i.e., constipation), such as increasing fibre and fluid intake, and the use of over-the-counter laxatives, are generally ineffective in PD patients, and approved compounds such as guanylate cyclase C agonists and selective 5-hyroxytryptamine 4 receptor agonists have demonstrated limited efficacy. Thus, identification of potential targets for novel therapies to alleviate PD-induced GI dysfunctions are essential to improve clinical outcomes and quality of life in people with PD. Unlike the central nervous system (CNS), where PD pathology and the mechanisms involved in CNS damage are relatively well characterised, the effect of PD at the cellular and tissue level in the enteric nervous system (ENS) remains unclear, making it difficult to alleviate or reverse GI symptoms. However, the resurgence of interest in understanding how the GI tract is involved in various disease states, such as PD, has resulted in the identification of novel therapeutic avenues. This review focuses on common PD-related GI symptoms, and summarizes the current treatments available and their limitations. We propose that by targeting the intestinal barrier, ENS, and/or the gut microbiome, may prove successful in alleviating PD-related GI symptoms, and discuss emerging therapies and potential drugs that could be repurposed to target these areas.