22. Why you need to grow your muscles: Sarcopenia Explained

What if I told you that having less muscular strength is in fact an established disease now?

Well…. There’s a bit more to it than this but definitely something you should think about.

The tenth revision of the International Classification of Diseases (or ICD-10) identifies this condition named Sarcopenia as a state of low muscle mass together with low muscle function (strength or performance). *(ICD-10-CM (M62. 84))

Experts on the matter (EWGSOP & EWGSOP2) defines it as:

But It doesn’t have that ‘ominous’ or ‘doomful’ ring to it, right?

Don’t let it fool you though, emerging research and good-quality evidence suggest that it’s one of the major factors in disease, disability, and disease/pain-related suffering later on.

Let’s begin by redefining and explaining what it is before we go on to the fact that it’s extremely overlooked and undertreated.

Sarcopenia for those who are unfamiliar with how scientific nomenclature works is made up of two obviously Greek words,

'sarx' – the flesh and 'penia' – loss 

I.e., loss/poverty of flesh or loss of muscle tissue to be specific. Based on this; researchers have previously emphasized a lot on the importance of the quantity of muscle loss and the quality of muscle tissues in sarcopenic populations,

It sounds easy enough though, 1. get a person 2. find out how much muscle and 3. what quality of muscle do they have

And BAM! sarcopenified! (Or something to that effect)

In reality, it’s a bit more difficult than that, clinically we don't have enough reliable and validated measures, enough normative data, or easy access to those tests & methods available to researchers to be able to identify and manage the disease effectively in this way.

Thus, presently we use the most reliable measure of muscle function: Muscle Strength, as a primary parameter of sarcopenia. (And when low muscle strength, low muscle quantity/quality, and low physical performance are all detected, sarcopenia is considered severe.)

I won’t go into much detail on the diagnosis of sarcopenia and how to go about it, but we’ll touch upon a few key details about it in the following sections.

Key Detail 1: There is more to it than being ‘age-related’

Advanced age is when Sarcopenia is ‘seen’, it begins a lot earlier.

When first used, the term sarcopenia referred to an age-related loss of muscle mass and function, and since then the fact it’s age-related (seen in people 40-50 Years or older) has stuck with us, for a while clinicians and scientists didn’t seem to consider that manifestation of disease at an advanced age doesn’t discount the fact that something somewhere in the lines of early development and young-adulthood could affect the disease process.

Muscle mass and strength are not constant, they naturally vary through our lifetime, generally increasing with the growth in youth and young adulthood, being maintained in midlife, and then decreasing with aging.

We (non-athletic people) usually attain our peak muscle mass somewhere around 30-40 years of age and at age 50 and beyond our body begins to lose strength and muscle mass (1-2% per year). (This is when sarcopenia supposedly becomes evident as previously thought)

Thus, being deconditioned and having low muscle mass and strength at ~40 years could mean that loss would likely be more noticeable and impactful to one’s future health) But, the authors also state that if at this age you are above the threshold of low physical activity (i.e., you are physically active and moving around well) you are likely to be above the risk of disability

And,

Interestingly some authors have also demonstrated that; “birth weight and weight at 1 year are significantly positively associated with adult grip strength” which is a primary parameter in clinical assessment and diagnosis of the condition in the community. (Here, here)

We might have to reconsider whether sarcopenia is only an aging-related disease.

Key Detail 2: Quick Identification is important.

Sarcopenia is so underrated that many clinicians often assume that sarcopenia is a diagnosis of exclusion,

For those who are unfamiliar if disease X is a ‘diagnosis of exclusion’ we can only say that a person has disease X if we have ruled out other possible ‘similar’ conditions successfully.

But that’s not the case for sarcopenia, it often presents with underlying malignancies

(cancer), organ failures or other systemic conditions.

Which makes diagnosing this already undertreated issue more complicated and vague.

Recent developments and a simplified approach have reduced it into 3 relatively easy steps.

1) Check for strength (Grip strength is commonly used): If weak- Probably Sarcopenia

2) Check for muscle mass (ASMM(skeletal muscle mass) by DEXA/MRI, Mid-thigh or L3 CSA(Cross-sectional area) by CT)

If less- Definitely Sarcopenia

3) Check for functions (TUG(timed up and go), SPPB(Short physical performance battery), Gait velocity @ 4m walk) If impaired- Severe Sarcopenia

Now, this is still complicated for regular folks.

So, to simplify it more,

Step one is sufficient for us to start working on sarcopenia and its primary management (Resistance exercise and Dietary modifications),

You can also use the following 5-part questionnaire to self-administer a screening for sarcopenia,

If you score 4 or more, you should get evaluated.

Or, if you get a chance to measure and you find that your grip strength is:

Get on it! consult a clinician.

Key Detail 3: If not sarcopenia then what?

Usually, a visual inspection isn’t enough to ascertain almost anything, let alone something complex such as sarcopenia.

Even then a simple observation could be a crude marker of progress (reduction of muscle mass or general body mass) in the elderly, for example, note how elderly people seem to get leaner through the years, even though they may have put on some body fat.

Noticing this could be a step in the right direction, as sarcopenia, if present and severe, could be detrimental to their health via’ falls, fractures, functional disability, and even mortality.

But it’s not always sarcopenia,

It could be either frailty, cachexia, or malnutrition that’s mimicking/accompanying the disease.

1. Frailty is unintentional weight loss, self-reported exhaustion, weakness (Low grip strength), slow walking speed, and low physical activity. Overall, a state of poor tolerance to stressors and impaired resolution of homeostasis after a stressful event. Simply put, a ‘frail’ person’s body would be relatively less likely to recover or normalize its ‘balance’ after significant stress like a chronic disease, surgery, etc.

2. Cachexia is a complex disorder of excess catabolism and inflammation, endocrine changes, and neurological changes associated often (historically even) with system conditions like cancer, HIV and AIDS, or end-stage organ failure.

It does seem precisely like sarcopenia with severe weight loss and muscle wasting, but the mechanism of both differ quite significantly, often the two conditions can overlap making the implications even more severe.

3. Malnutrition as we all know is where nutritional factors like • Low protein intake

• Low energy intake

• Micronutrient deficiency

• Malabsorption and other gastrointestinal conditions

• Anorexia • Ageing and oral problems

This could lead to a state of reduced muscle mass but with relatively normal muscle strength, which on an initial sighting could seem like sarcopenia but isn’t.

All of these conditions closely resemble sarcopenia in the way they affect our bodies and the way they mimic identifiable parameters of sarcopenia, and they can be seen often with sarcopenia as well.

So, when you suspect sarcopenia in your patients, close ones, or even yourself; watch out for these mimickers as they might require immediate and priority care. (Here)

Moving on.

Key Detail 4: What to do about it?

The sixty-four-thousand-dollar question, What can we do about sarcopenia? Or malnutrition, low functional capacity, sarcopenic obesity, etc. (More details on types of sarcopenia in future blogs)

For the scope of this blog and context, I’ll discuss only the extremely simplified answer to this complex question, which is

1. RESISTANCE TRAINING

Experts and clinicians across different fields and specializations of healthcare seem to agree that resistance training is fundamental in the management & prevention of sarcopenia and its impact on general health and otherwise.

Evidence-based clinical guidelines strongly recommend;

Literature and evidence for progressive resistance training (PRT) is compelling enough by itself for muscle mass and strength, and emerging evidence of the positive effects of PRT specifically for sarcopenia is steadily growing as well.

Even though it might not be ‘THE’ intervention for sarcopenia, resistance-based exercise and its overall benefit in the elderly (as a vague extension; sarcopenic) population makes it a logical ‘safe bet’ and primary care for sarcopenia management.

Keep in mind that even if (≤50 RM) is enough to develop muscle mass, for MAX GAINZZ try and program high-intensity RT (~80% 1RM). (here) You can also use BFR (blood flow restriction) and multimodal exercises as well if you are up to it. (Here, here)

2. NUTRITION

Adequate protein intake and physical activity are the main constructive stimuli for muscle protein synthesis. Along with Total energy intake which

(although inconclusively) determines factors like sarcopenic obesity (more fat mass & less muscle mass).

I am no expert in nutrition, but I can crudely explain a few things the guidelines, researchers, and clinical experts seem to agree upon. (here, here)

A. Adequate protein intake:

• Adults should take 25 - 30 g of high-quality protein per meal daily (emphasis on “high quality”). *Presence of any underlying condition can alter this advice.

B. Total energy intake:

• Total energy intake (in calories) if significantly reduced could even produce muscle loss (fat-free mass to be precise) in obese individuals, *A crucial detail in people with sarcopenic obesity.

C. Vitamin D supplementation:

• By itself, it doesn’t mean much for the management. *Adjusted (to ethnicity) amount of supplementation can be given in people with low Vit-D levels.

D. Anabolic Hormones and Drugs:

• No reason to take or prescribe anabolic hormones for sarcopenia.

• Although a few promising drugs are under development, currently there isn’t any medication that directly corresponds to this condition.

So, to conclude.

Sarcopenia as a ‘musculoskeletal’ sounding disease, doesn’t have that usual gloomy or deadly ring to it, but it is in fact an actual ‘silent killer’ of sorts.

Often seen in the elderly, this condition has potentially serious and devastating implications depending on the age, stressors, and other contextual factors that are at play.

From increased mortality post emergency surgery in the elderly to increased risk of falls & fractures in people with sarcopenia and additional disability in pre-existing systemic conditions like multiple organ failure, malignancies (cancer) & potentially pain experiences as well, Sarcopenia is but a dreaded little goblin, sucking away any chances of uneventful survival a person might have.

It is not to be taken lightly. And with simple positive lifestyle behaviors (like regular exercise and proper nutrition) as preventative measures and treatment alike, it may as well be the modifiable factor we cater to for a better and hopeful life later.

(Here, here, here, here, here, here, here)

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Disclaimer: This blog is for educational purposes only. Cover Photo by Michael Scott from Pexels