Australian Prescriber最新文献

Established drug therapies for Alzheimer disease (cholinesterase inhibitors and memantine) do not modify the disease course and provide only modest clinical benefit. Biomarker measures of amyloid, tau and neurodegeneration have been integral to Alzheimer disease clinical trials for biologic drugs, for patient selection and efficacy monitoring. At the time of writing, two monoclonal antibodies targeting the amyloid-beta protein (aducanumab and lecanemab) have been approved in the USA, and two agents (lecanemab and donanemab) are under evaluation by the Therapeutic Goods Administration in Australia. Clinical trials have demonstrated that monoclonal antibodies are effective at removing amyloid from the brain in people with early Alzheimer disease. Cognitive benefits are statistically significant, but do not achieve the minimal clinically important difference. Amyloid-related imaging abnormalities of vasogenic oedema and microhaemorrhages occur more frequently on treatment; although these are usually asymptomatic or transient, in some people they are serious or fatal. Targeting amyloid as a unimodal strategy is unlikely to be sufficient and future therapies may need to be multimodal, targeting multiple pathogenic pathways. The burden of dementia is greatest in the older population where mixed dementia pathology dominates; the relationship between biomarkers, clinical phenotype and pathology attenuates; and frailty and comorbidity impact cognition. This creates challenges in identifying effective therapies for the group where dementia is most prevalent.

Community-acquired pneumonia (CAP) is a common infectious syndrome in Australia and a leading global cause of morbidity and mortality. It drives a significant amount of antimicrobial prescribing in Australia. Accurate assessment and stratification of CAP severity is important. However, adequate evaluation is challenging and controversy remains about the optimal method. Streptococcus pneumoniae is the most commonly identified bacterial pathogen causing CAP. As such, oral amoxicillin monotherapy is the mainstay of empirical therapy for low-severity CAP. The need to start empirical therapy for pathogens such as Mycoplasma pneumoniae and Legionella species in low-severity CAP remains controversial; evaluating the causative pathogen on clinical grounds alone is difficult. Oral antibiotics recommended for CAP (e.g. amoxicillin, doxycycline) have excellent bioavailability and may be used instead of intravenous therapy in some hospitalised patients. A duration of 5 days of antibiotic therapy is recommended in clinical practice guidelines for patients with uncomplicated CAP who meet stability criteria at follow-up.

Antihypertensive drugs are commonly used by older adults because of the high prevalence of cardiovascular disease and its risk factors, and the increased absolute benefit of blood pressure reduction with increasing age. Clinical trials of blood pressure reduction in older adults have generally excluded older adults with multimorbidity, frailty and limited life expectancy. In this population, the benefit-harm ratio of aggressive blood pressure lowering may become unfavourable; a more relaxed blood pressure target may be appropriate; and deprescribing (cessation or dose reduction) of one or more antihypertensive drugs can be considered. Before deprescribing an antihypertensive drug, it is important to consider other indications for which it may have been prescribed (e.g. heart failure with reduced ejection fraction, diabetic nephropathy, atrial fibrillation). Evidence from randomised controlled deprescribing trials indicates that it is possible to deprescribe antihypertensives in frail older people. However, some patients may experience an increase in blood pressure that warrants restarting the drug. There are limited data on long-term outcomes (follow-up in deprescribing trials ranged from 4 to 56 weeks). The risk of adverse outcomes associated with deprescribing, such as withdrawal effects, can be minimised through appropriate planning, patient engagement, dose tapering and monitoring.