5th October 2018, Volume 131 Number 1483

Alzheimer’s disease research: the future of BACE inhibitors

The build-up of beta-amyloid proteins in the brain is a hallmark of Alzheimer’s disease. Beta-site amyloid precursor protein cleaving enzyme (BACE) inhibitors such as lanabecestat prevent the production of beta-amyloid.

However, trials using oral lanabecestat in patients with Alzheimer’s disease have recently been stopped as the treatment has not been shown to improve cognitive status in those treated. Two similar BACE inhibitors, atabecestat and verubecestat have also been trialled in Alzheimer patients. These trials have also been stopped as they have been unsuccessful.

Professor Vassar who co-discovered BACE-inhibitors opines that they are not going to be effective in subjects who already have signs of dementia.

Lancet 2018; 391:2486

Vitamin supplements for the healthy?

In this comprehensive review of the topic the author notes that complementary medicines are a multibillion-dollar industry of which vitamin supplements are an important component.

He reports that claims of benefit are not evidence-based. Adverse reactions may occur with some vitamins, particularly when high doses are taken.

It is concluded that there is no case for vitamin supplementation in normal healthy non-pregnant or lactating adults who are receiving the recommended daily intake of nutrients. The exception is folic acid and it is noted that folate supplementation has been undertaken in some foods in Australia and New Zealand since 1996 to decrease the incidence of neural tube defects.

Internal Medicine Journal 2018; 48:901–907

Platelet counts during pregnancy

Platelet counts of less than 150,000 per cubic millimetre during uncomplicated pregnancies are described as gestational thrombocytopenia if no alternative cause is identified. Platelet counts may be even lower in women with pregnancy-related complications.

This report concerns a study which compares platelet counts in pregnant women with those of non-pregnant women. The researchers found that the platelet count was significantly lower in the first trimester of pregnancy than in non-pregnant women.

It was concluded that platelet counts in all women decrease throughout pregnancy, beginning in the first trimester. Severe thrombocytopenia is rare, even in women with pregnancy-related complications. In women with platelet counts below 100,000 per cubic millimetre who do not have preeclampsia or a pre-existing disorder associated with thrombocytopenia, a cause other than pregnancy or its complications should be considered.

N Engl J Med 2018; 379:32–43