Sarcopenia & diet

Introduction

Many thanks to Pam Schoenfeld for this week’s note. Pam sent this week’s paper to me in February 2019 and I’ve kept it as one to look at since. I had the privilege of seeing Pam present at a conference in Minneapolis in 2017. She is a dietitian and nutritionist and specialises in women’s health (Ref 3).

The particular paper that caught Pam’s eye was about sarcopenia and diet in very elderly people – participants in the Newcastle 85+ study in this case (Ref 4). Sarcopenia is a progressive and age-related loss of muscle mass and strength, which usually starts in the fifth decade of life and increases in prevalence to approximately 12.5% to 50% in adults aged over 80 (Ref 5). The Newcastle 85+ study is a population study involving over 1,000 participants (birth cohort 1921) who were registered with general practices in Newcastle and North Tyneside, UK.

By the way

Before I get to the subject of this week’s note, some of you may have seen a story in the newspapers last week: “Taking statins won’t lead to a loss of memory.” The headlines came from a paper in the Journal of the American College of Cardiology (Ref 1). The paper isn’t on open view, but I’ve got a copy. The study was conducted in Australia and it used participants in an ongoing observational study called the Sydney Memory and Ageing Study. This involves appropriately 1,000 Australians aged 70-90 years old.

From this group of participants, 395 people (58% male) who had never taken statins were compared with 642 people (72% male) who had taken statins. The statin takers had been taking statins for an average of nine years. Both groups were then given several memory and cognitive function tests over the following six years. The study essentially found no significant difference between people who had never taken statins & people who had taken them. The researchers thus claimed that the widespread consumer concern that statin use may be associated with impaired memory is unfounded.

The key flaw in the study is that we know that almost half of people stop taking statins within a few months of starting them. A 2017 paper reported that only 61% of those who were prescribed a statin were still using the drug after 3 months; and only 55% remained on the drug after 6 months (Ref 2). What if those people who suffered cognitive impairment stopped statins soon after starting them? These people weren't studied.