• Overall, the results show that more women (29,6%) than men (16,5%) had depression symptoms.
• The mean grip strength values for men and women were 44.6 kg and 27.9 kg.
• In total, being above specific grip strength cut-off values was associated with a lower probability of currently having depression (in 2011) and having depression four years later (in 2015) for men and women.
• Low grip strength values are connected to a potential depression risk and could be incorporated as an indicator and screening tool for depression.
• Overall, measuring grip strength could be an easy and inexpensive method in the diagnosis process to identify people at risk and to avoid negative health outcomes.

(December 2021) Depression is a severe mental health issue that has negative impacts on individuals’ general health. Although being a high burden for those affected, depression often remains underdiagnosed and poorly treated. Diagnosing depression is a complex process. Thus, finding a simple way to screen for depression symptoms could be helpful. As it is already confirmed that physical activity and muscle strength have an overall positive impact on depression, the question arises whether physical measurements such as grip strength could be used as a screening tool for diagnosing depression. Thus, the present study uses data from the Survey of Health, Ageing and Retirement in Europe (SHARE) to examine whether grip strength is as an indicator of depression as well as to explore grip strength cut-off points (threshold of muscle weakness) for depression by sex and age.

Exploring grip strength as an indicator of depression among Europeans aged 50+ with SHARE data

To assess the connection between grip strength and depression, the researchers analysed data from over 20,500 respondents aged 50+ from SHARE Wave 4 (2011) and Wave 6 (2015) from 14 European countries (Austria, Belgium, Czech Republic, Denmark, Estonia, France, Germany, Italy, Poland, Portugal, Slovenia, Spain, Sweden, and Switzerland). The authors focused on the age groups 50-64 years and ≥ 65 years, as elderly people are particularly at risk for developing depression symptoms.

Depression symptoms and grip strength were measured in 2011 and four years later (in 2015). Participants’ depression symptoms were rated by the EURO-D scale, a scale to assess depression prevalence by scores ranged between 0 and 12. Higher scores indicate higher levels of depression. Clinically significant depression can be defined as a EURO-D score greater than 4. Grip strength is an indicator of overall health and muscle strength. It was measured by using a dynamometer and asking participants to squeeze the dynamometer with their hands as hard as possible for 5 seconds. The specific threshold of muscle weakness that could lead to depression symptoms should be identified. 

Different threshold values for the presence of depression by sex and age

The researchers differentiated between sex and age group (50–64 years and ≥ 65 years) because grip strength varies strongly with both. Overall, the results show that more women (29,6%) than men (16,5%) had depression symptoms with score values ≥ 4. The mean grip strength for men were 44.6 kg and for women 27.9 kg. The following grip strength muscle thresholds for discriminating the presence of depression by sex and age groups could be identified: 43.5 kg for men and 29.5 kg for women aged 50–64 years, 39.5 kg for men and 22.5 kg for women aged ≥ 65 years. Those values were associated with the probability of currently having depression symptoms and having depression symptoms four years later.

Individuals with grip strengths values above the cut-offs have significant lower probability for depression for both sex and age groups

In general, being above the grip strength cut-off values was associated with a lower probability of currently having depression symptoms (in 2011) and having depression four years later (in 2015) for men and women from both age groups: men aged 50–64 years and ≥ 65 years above the cut-off value were 25% and 29% less likely for having depression in 2011 and 24% and 16% less likely for having depression four years later. Women aged 50–64 years old and ≥ 65 years above the cut-off values were 32% and 20% less likely in 2011 and 44% and 31% less likely in 2015 for having depression.

Low grip strengths cut-off values can be indicators of a potential depression risk

In total, the results show that having grip strength values above the cut-off represents a significant lower probability of currently having depression symptoms and of having depression symptoms four years later. The authors highlight the results as important knowledge to consider low grip strength cut-off values as potential depression risk. However, assessing grip strength is not enough to identify depression, but could be helpful as a first screening step to identify people at risk and to provide care.

Assessing depression as a priority of public health systems

To conclude, the study shows that grip strength should be incorporated as an indicator and screening tool for depression. According to the authors, healthcare practitioners should be alert to the potential of depression in patients below the grip strength cut-off values. Nevertheless, further diagnosis is required to identify depression. Due to the high burden of affected people, the results are important for exploring depression indicators and diagnosis tools. The authors suggest that research, diagnosis and treatment of depression as a mental health issue should be a priority of public health systems.

Depression is a complex mental disorder that requires early detection and individualised screening processes. Grip strength is an overall indicator of muscle strength and mental health. Therefore, measuring grip strength could be an easy and inexpensive method in the diagnosis process to identify people at risk and to avoid negative health outcomes.

Study by Adilson Marques, Duarte Henriques Neto, Miguel Peralta, Priscila Marconcin, Élvio R. Gouveia, Gerson Ferrari, João Martins and Andreas Ihle (2021). Exploring grip strength as a predictor of depression in middle‑aged and older adults. Scientific Reports 11. DOI: 10.1038/s41598-021-95566-7.

URL: https://doi.org/10.1038/s41598-021-95566-7

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