Introduction

Have you ever heard of metabolic syndrome? If not, this is understandable since it has been under-recognized. Metabolic syndrome is a term to describe the presence of metabolic risk factors that raise the risk of chronic diseases. It causes chronic low-grade inflammation and can therefore be linked to many chronic diseases such as osteoarthritis, back pain, and tendinopathy. People with metabolic syndrome are twice at risk of developing cardiovascular disease and fivefold the risk of developing diabetes. Primary care practitioners should be able to recognize this condition since it has been linked to the development of chronic health problems. When identified, a treatment plan can be established to prevent chronic illnesses and lower the co-existing low-grade inflammation, thereby contributing to improved musculoskeletal conditions frequently encountered in physiotherapy practice. This study wanted to investigate the presence of metabolic syndrome in primary care physiotherapy practice.

Methods

In this observational study, clients presenting for physiotherapy were recruited in Australia. They had to be at least 18 years of age. The participants were screened for the presence of metabolic syndrome, which was the primary outcome of this study. This was defined as having at least 3 out of 5 risk factors:

1. Abdominal obesity, defined by waist circumference
   • Waist circumference measurements were obtained from the narrowest point between the lower ribs and the iliac crest while the patient was standing with the abdomen relaxed.
     • Caucasian ≥ 94cm (males), ≥ 80cm (females)
     • European ≥ 102cm (males), ≥ 88cm (females)
     • Asian ≥ 90cm (males), ≥ 80cm (females)
   • Elevated triglycerides
     • Serum triglyceride ≥ 2.0 mmol/L
     • Or taking medication for elevated triglycerides
   • Reduced HDL-cholesterol
     • Serum HDL-cholesterol < 1.0 mmol/L (males) or <1.3 mmol/L (females)
     • Or taking medications for reduced HDL-cholesterol
   • Elevated blood pressure
     • Systolic ≥ 130 mmHg and/or diastolic ≥ 85 mmHg
     • Or taking medication for hypertension
   • Elevated random blood glucose
     • < 7.8 mmol/L
     • Or diagnosed (pre-)diabetes
     • Or taking medication for elevated glucose

Secondary outcomes included physical activity, diet, and the importance of lifestyle change to manage chronic disease.

• Physical activity was measured using the 7-item Physical Activity Questionnaire Short Form (IPAQ-SF). This is a self-report measure that assesses physical activity over the last week. The patients respond to the questions and can be classified as high, moderate, and low physical activity. The metabolic equivalents of tasks (METs) can be derived from this assessment as well.
• Diet was measured using the 38-item Commonwealth Scientific and Industrial Research Organisation (CSIRO) Healthy Diet Score Survey. The total score ranges between 0 and 100 with a higher score reflecting better adherence to the Australian Dietary Guidelines.
• The importance of making lifestyle changes according to the participants was rated on a visual analogue scale from 0-100. Their confidence to make lifestyle changes and their interest in participating in a lifestyle change program were also rated. 0 indicated no importance/confidence/interest.
• Further information on socio-demographic status, lifestyle factors, personal medical history, and their diagnosis requiring physiotherapy treatment was also collected.
• Anthropometric measurements included height and weight to calculate the body mass index (BMI).

Results

Two hundred and thirty participants were included in the study. 63 percent of the participants were female. Their mean age was 54 years and 71% were overweight or obese since their BMI was ≥ 25 kg/m2. Ninety-four participants presented for physiotherapy for musculoskeletal or orthopedic conditions.

84 (37%) of the 230 participants were positive for the presence of metabolic syndrome. Importantly, none of the participants were aware. The most common risk factor was the presence of hypertension in 89% of the participants. More than half of the participants did not know they had elevated blood pressure and were thus not taking any medications. Of those categorized as having metabolic syndrome, 88% had an elevated waist circumference and 81% had high triglycerides and low HDL cholesterol.

The presence of metabolic syndrome was higher in people living in areas of greater socio-economic disadvantage, in older people, and in people not employed. The people with metabolic syndrome were less physically active.

The logistic regression revealed that age and socioeconomic status were related to the model. Every year increasing age increases the odds of developing metabolic syndrome by 6%. When a participant was living in a socioeconomically advantaged area, the risk of having metabolic syndrome was 72 to 88% less likely compared to a participant living in a socioeconomically disadvantaged region.

Questions and thoughts

What should you remember about this study? As a physiotherapist, you will encounter people presenting with musculoskeletal complaints. Some of them will have a clear mechanism of onset and may be treated accordingly. Others will present with more chronic complaints that may be partially driven by the presence of metabolic syndrome and the associated underlying low-grade inflammation. This was shown by this study since the prevalence of metabolic syndrome in this population was 37% compared to 25% in the general population. For example, people with osteoarthritis can benefit from your treatment approach but may achieve better results when the underlying cause is addressed too. Considering the spine, Guo et al. (2024) demonstrated that metabolic disturbances significantly impacted spinal intervertebral disc disease more than biomechanical alterations. This further supports the theory that your spine (and possibly other joints) doesn’t wear and tear from excessive loads, movement faults, or bad postures. Maybe these conditions become painful because of low-grade inflammation sensitizing your tissues. Especially, since many people without back pain have disk bulges or protrusions, which was already demonstrated 30 years ago by Jensen et al., in 1994!

You can easily make a judgment by the presence of these metabolic risk factors. You can already make a first screen by taking people’s waist circumference, blood pressure, and a capillary blood test for blood glucose. If 3 out of 3 are positive, this confirms the presence of metabolic syndrome. With only 1 or 2 positives, you should further test for triglycerides and HDL-cholesterol. In Belgium, where I practice, physiotherapy is secondary care, meaning we rely on a referral from people’s general practitioner for physiotherapy. Instead of taking these blood measurements myself, I would make a telephone call to the general practitioner to learn more about these blood tests in my patient. Yet, in many countries direct access to physiotherapy is possible and you can obtain the blood glucose measure easily with a nonexpensive AccuCheck device. For obtaining the triglycerides and the HDL-cholesterol, a more expensive device was used, for which you can maybe rely on the general practitioner to assess it.

One of the primary causes of the development of metabolic syndrome is an inadequate energy balance caused by excessive calorie intake and insufficient physical activity (PA). Besides lifestyle adjustments (including dietary modifications, better sleep, quitting smoking, and limiting alcohol intake), increasing physical activity seems of utmost importance. Here your role as a physiotherapy practitioner is of extreme importance. “Achieving or exceeding physical activity requirements reduces the risk of metabolic syndrome while improving parameters in those who have already developed metabolic syndrome or its components.” Chomiuk et al., (2024) When the participants of the current study were asked about it, those with metabolic syndrome were less confident about their abilities to change their lifestyle. That is where you may provide guidance and make a difference!

Talk nerdy to me

Participants could also be positively classified as having metabolic syndrome when they took medications to control their metabolic risk factors. For example, someone who took anti-hypertensive medication was classified as positive for high blood pressure. Yet, when taking these medications, I would assume that the blood pressure is treated and within normal ranges.

This analysis showed that people from socio-economically disadvantaged regions were at higher risk for metabolic syndrome. Equally, older people were more likely to develop or have metabolic syndrome. These factors cannot be addressed by physiotherapy, so the importance of addressing the modifiable risk factors arises even more.

A strength of the current study was the use of objective criteria to determine the presence of metabolic syndrome. This was done according to the criteria of the International Diabetes Federation (IDF) the American Heart Association, and the National Heart, Lung, and Blood Institute (AHA/NHLBI).

The model of the regression analysis with the significant variables age and socioeconomic disadvantage showed a good fit, yet could only explain 27% of the variance in the presence of metabolic syndrome. That would mean that more than these two variables explain the presence of metabolic syndrome. Yet, lifestyle-related factors such as physical activity, smoking status, alcohol intake, and diet remained insignificant in the regression model.

A limitation of the current study is that diet and physical activity were assessed by self-report questionnaires which may be subject to under- and overestimation of physical activity, or recall bias.

Take-home messages

As a physiotherapist, you can play an important role in the prevention and treatment of metabolic syndrome. As this study showed that the prevalence of metabolic syndrome is higher in people presenting in physiotherapy practice compared to the general population, this is especially important since the presence of metabolic syndrome increases the risk of severe health conditions in the future (including diabetes, heart disease, and stroke), but can be implied in sensitizing more common musculoskeletal conditions as well. By increasing the physical activity of a person with metabolic syndrome you can already make a huge difference if this is combined with lifestyle modifications.

Reference

Mastwyk, S., Taylor, N. F., Lowe, A., Dalton, C., & Peiris, C. L. (2024). Metabolic syndrome is prevalent and undiagnosed in clients attending private practice physiotherapy: A cross-sectional study. Physiotherapy.