Suboptimal health: An unmet need in public health

Do we need to manage symptoms that do not perfectly align with a specific disease?

Learn more about this challenging subclinical state that may be damaging to your patient’s overall health.

What is suboptimal health status?

Suboptimal health status (SHS) has become a growing health concern worldwide.1,2 It is a subclinical state (i.e. a physical state between health and disease) characterised by fatigue and a constellation of other physical symptoms, but with no diagnosable disease condition.3,4 SHS is also commonly referred to as medically unexplained symptoms (MUS) or functional somatic syndrome.5,6

The SHS concept was coined following an increased number of people with ambiguous health complaints in the absence of a disease.3 The World Health Organization (WHO) introduced a similar concept in Chapter XVIII of the International Statistical Classification of Diseases and Related Health Problems 10th revision (ICD-10) by listing various conditions of discomfort and physical signs, highlighting there was no clear disease classification.7

How does SHS impact those affected?

Individuals with SHS suffer from symptoms such as chronic fatigue, headaches, dizziness, depression, anxiety, non-specific pain and functional disorders which may progress to overt chronic diseases.8 These individuals often present with reduced organ function and physical functionality, energy loss, low cognitive and emotional performance or decline in social functioning – all of which cannot be diagnosed as a disease by modern medical diagnostic criteria.9 Therefore, SHS may be associated with substantial socioeconomic impact such as impairing quality of life, increasing frequency of hospital visits and increasing medical expenses to those comparable with major chronic disorders.

About one in every two individuals have SHS.8,10 Several cross-sectional studies have estimated SHS prevalence at 51%, 46% and 56% in college freshmen in Beijing,1 individuals aged 12 to 80 years old in Southern China2 and students in Guangdong,11 respectively. The importance of SHS as a growing health concern has driven multiple studies worldwide including the formulation of a diagnostic and treatment algorithm for SHS;12 applying SHS in the population as a risk assessment for chronic diseases such as diabetes,13 and as a predictor of job hopping behavious.14

Why is identifying SHS important?

Identifying SHS plays an important role in the early detection and prevention of non-communicable chronic diseases. SHS is associated with classical cardiovascular risk factors such as blood pressure, glucose, lipid levels and cortisol.15 An association between SHS prevalence and systolic blood pressure, diastolic blood pressure, plasma glucose, total cholesterol and HDL cholesterol was found in a cross-sectional study of urban Chinese workers.15

What are risk factors of SHS?

SHS prevalence was found to increase with age – a trend consistent with the prevalence of metabolic syndrome and cardiovascular disease in the general population.15 Indicators of endothelial dysfunction – contributing to the risk of developing cardiovascular disease – were correlated with SHS severity.16 Unhealthy lifestyle including poor dietary habits, smoking, sleep deprivation and physical inactivity that are associated with the development of cardiovascular disease has also been shown to be a risk factor for SHS.11,17

Furthermore, stress is a risk factor of SHS which could affect mental well-being.18-20 The impact of stress-related psychosocial work factors on an individual’s health has been well documented.18 Repetitive work, increasing job demands, irregular and long working hours, job insecurity, and low job satisfaction are important factors associated with the prevalence of SHS. An observation of higher level of plasma cortisol and decreased mRNA expression of glucocorticoid receptor α  in the lymphocyte supports the evidence of psychosocial stress being an important risk factor of SHS.19  An elevated plasma cortisol is often observed following an exposure to a stressor while glucocorticoid receptor α serves as a biomarker of exposure to chronic stressors.19 Another study among Chinese college students found that psychological symptoms such as somatisation, obsessive compulsive, interpersonal insensitivity, depression, sleep deprivation and dietary problems are positively correlated with SHS severity.20

The rapid economic progress across developed and developing countries is attributable to the increasing prevalence of SHS. Emerging evidence on the association between SHS and risk of developing chronic diseases as well as its impact on mental health suggest the importance to address SHS. Healthcare professionals can play a significant role in recommending holistic health interventions to manage SHS and avoid inappropriate treatments and progression to chronic disease.4,11


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