The association between handgrip strength and depression in cancer survivors: a cross-section study

DOI: https://doi.org/10.21203/rs.3.rs-911912/v1

Abstract

Background

The association between handgrip strength and depression in cancer survivors was unknown. We aim to examine the associations of handgrip strength and depression in cancer survivors by using public data (National Health and Nutrition Examination Survey).

Methods

We combined two waves of the data of the National Health and Nutrition Examination Survey during 2011-2014 to explore this important issue. The variable of handgrip strength was extracted by the maximum value of each hand. The depressive symptom was assessed by the Patient Health Questionnaire (PHQ-9) with the cut-off >=10 points indicating depressive symptoms. Other characteristics and health-related variables were evaluated. Multivariable logistic regression models were adopted to explore the associations between handgrip strength or low handgrip strength and depressive symptoms by adjusting for potential confounding factors.

Results

There were 992 cancer survivors in our final analysis, with 456 (45.97%) male and the mean (SD) age of this whole group being 64.75 (14.02) years. The prevalence of low handgrip strength and depression was 20.36% and 13.31%, respectively. The results showed that handgrip strength was negatively associated with depression (OR=0.97,95%CI:0.96-0.99; P=0.01). In addition, after adjusting age, race, education, marital status, sleep disorder, history of stroke, polypharmacy and BMI, cancer survivors with low handgrip strength had a 2.11-fold risk of depression, compared to those with normal handgrip strength (OR=2.11,95%CI:1.19-3.73; P=0.01).  

Conclusions

Low handgrip strength, simple and modifiable parameter, is associated with a higher risk of depression in cancer survivors. Prospective cohort studies are warranted to confirm this association in the future. 

Introduction

The number of cancer survivors is increasing thanks to the variety of multiple advances of technology and medicine and the aging society1. Meanwhile, cancer survivors were often suffering depression symptoms, with an estimated figure of 20%, as compared to 5% in the general population2. A meta-analysis reported that the prevalence of major depression and minor depression was 15% and 20%, respectively3. Cancer patients with depression could have an increased risk of adverse outcomes, such as poor adherence to medical treatment4, lower survival time5, even more likely to suicide6, bringing tremendous attention to clinicians and society. Therefore, early identification of risk and corresponding management for depression among cancer patients was essential.

Several factors, serious illness, female gender, social deprivation, and other health-related factors, are associated with depression7. Apart from these abovementioned factors, functional limitations such as low handgrip strength are becoming the hotpot topic for the researcher to explore with depression810. A previous study indicated that muscle mass could influence depression by secreting myokines11 and muscle mass as the main component of organ to maintain the function of physical activity. Apparently, regular physical activity was associated with decreased risk of depression12. Handgrip strength, as an indicator of the function of muscle mass, can be easily obtained by dynamometer, widely applied in different settings. In addition, handgrip also used a parameter to assess the nutritional status of patients.

The association between handgrip and depression has been widely explored among community-dwelling older adults, with the results being that older adults with high handgrip strength had a lower risk of depression symptom13, 14. Furthermore, in a recent meta-analysis, handgrip strength was associated with depression (Pooling OR = 0.85,95%CI:0.80,0.89), indicating handgrip strength as a protective factor for depression15. However, most of the including studies for meta-analysis were conducted among community or nursing home settings where participants were relatively healthy. In contrast, the association between handgrip strength and depression among cancer patients was unknown.

Therefore, the aim of this present study was to explore the association between handgrip strength and depression among cancer patients and examine the association of low handgrip strength based on the definition of sarcopenia with depression by using the public internet database of the National Health and Nutrition Examination Survey.

Methods

Study design and participants.

This cross-sectional study of National Health and Nutrition Examination Survey (NHANES) was to explore the overall picture of nutrition, health, and risk factors among residents in various states across the USA (Centers for Disease Control and Prevention-http://www.cdc.gov/nchs/nhanes.htm). This survey is based on national-scale adopting multistage and clustered sample methods with the figure of being 5000 participants each year. Voluntary participants were asked to finish physical examination and this study was approved by Health Statistics Research Ethics Review Board from national center. All the participants have signed the written consent.

In this present study, data including handgrip strength, depression, sleep disorder, cancer type, baseline characteristics, and other health-related variables were extracted from NHANES ranging from 2011 to 2012 and 2013 to 2014, aggregating for final analysis.      

Cancer diagnosis

Cancer patients was confirmed by asking about the question (Have you even been told by the doctor that you had been diagnosed with any type of cancer). We selected the patients whose answer is “YES.”

Handgrip strength

The detail of muscle strength measurement was depicted in NHANES Procedure Manual. Briefly, those participants who are able to finish the test obeyed the standard procedure. Investigators explained the detailed information and asked participants to squeeze the dynamometer as hard as possible for three times, recording the maximum value as the participant’s final handgrip strength. In our present study, the definition of low handgrip strength was <27kg for males and <16kg for females16

Depressive symptoms

According to the Questionnaire Instruments, Patient Health Questionnaire (PHQ-9) was used to assess the depressive symptoms of participants, consisting of 9-items with each item ranging from 0 to 3 points17. The total points of PHQ-9 ranged from 0 to 27. We categorized participants into depression and non-depression, with the cut-off being 10 points based on the previous study, which was reported good sensitivity (88%) and specificity (88%) for identifying major depression18.     

Covariates definition

We extracted demographic characteristics including age, gender, education, race, marital status, and smoking. Of which, the race was defined as Non-Hispanic Black, Non-Hispanic White, and others; marital status was classified as married, widowed or divorced, and others. Regarding of education, four categories including less than 12 grades, high school, some college, and college graduated above were confirmed. Other covariates such as BMI, cancer diagnosis, sleep disorder, history of stroke, and history of Congestive Heart Failure (CHF) were also extracted. In addition, Leisure-time physical activity was assessed by Global Physical Activity Questionnaire19. The detailed calculation method was reported the previous study. In brief, we combined the vigorous and moderate intensities of physical activity each week, and we defined it as inactive and physical activity, respectively, with the cut-off of zero min/week.

Statistical analysis       

Continuous variables including age, BMI, Depression score were present as means and SD, and categorical variables including diagnosis, gender, race, education, marital status, sleep disorder, and other health-related variables were displayed as frequency (%). Comparisons for low handgrip strength versus normal handgrip strength and depression versus non-depression were conducted by Student’s-test and chi-squared test or Fisher’s Exact Test and Mann–Whitney tests, for appropriate. In addition, the generalized additive model (GAM) analysis was used to detect whether there is a non-linear relationship between handgrip strength and depression20. Before performing multivariable logistic regression analysis, we used Least Absolute Shrinkage and Selection Operator (LASSO) regression to select variables for the final regression model. The results indicated that these variables (age, race, education, marital status, sleep disorder, history of stroke, polypharmacy, BMI, handgrip strength) were selected. Finally, Multivariable logistic regression analysis was adopted to identify the independent association between handgrip strength and depression after controlling for potential confounding factors including age, race, education, marital status, sleep disorder, history of stroke, polypharmacy, BMI. We also categorized handgrip strength into low handgrip and normal handgrip according to the sarcopenia of the revised European consensus on definition and diagnosis, with the cut-off value being <16kg for females and <27kg for males. The association between low handgrip strength and depression was also detected by multivariable logistic regression analysis with adjustment of the same variables. Unadjusted subgroup analysis between low handgrip strength and depression was performed in terms of different variables( inactive versus active, >=65 versus <65, sleep disorder, congestive heart failure, polypharmacy, history of stroke, marital status, race, and education.) All the statistics were conducted by software packages R and Empowerstats, with the significant P-value being <0.05. 

Results

Baseline Clinical Characteristics

There were 992 cancer cases in this present study. Cancer patients include 222 Skin cancers (22.52%), 138 prostate cancers (14.00%), 64 melanoma cancers (6.49%),27 lung cancers (2.74%),117 gynecological cancers (11.87%),55 colon cancers (5.58%),157 breast cancers (15.92%) and 206 other cancers (20.89%). The mean (SD) age of this whole group was 64.75 (14.02) years, with 456 (45.97%) male. The prevalence of low handgrip strength and depression was 20.36% and 13.31%, respectively. Of these patients, 383(43.37%) participants experienced polypharmacy and 663 patients did not participate physical activity. Other detailed information was shown in Table 1.

Table 1

Baseline Clinical Characteristics

Variables

Total sample

Low handgrip strength

 

Standardize diff.

P-value

   

No

Yes

   

N

 

790(79.64%)

202(20.36%)

   

Age (years)(mean, SD)

64.75 ± 14.02

63.21 ± 14.09

70.77 ± 12.00

0.58 (0.42, 0.73)

< 0.001

BMI (kg/m2) (mean, SD)

28.95 ± 6.72

29.11 ± 6.65

28.29 ± 7.00

0.12(-0.04,0.28)

0.171

Diagnosis (n,%)

     

0.29 (0.13, 0.44)

0.070

Skin

222(22.52%)

185 (23.54%)

37 (18.50%)

   

Prostate

138(14.00%)

101 (12.85%)

37 (18.50%)

   

Melanoma

64(6.49%)

55 (7.00%)

9 (4.50%)

   

Lung

27(2.74%)

23 (2.93%)

4 (2.00%)

   

Gynecological

117(11.87%)

98 (12.47%)

19 (9.50%)

   

Colon

55(5.58%)

41 (5.22%)

14 (7.00%)

   

Breast

157(15.92%)

116 (14.76%)

41 (20.50%)

   

Others

206(20.89%)

167 (21.25%)

39 (19.50%)

   

Depression score (mean, SD)

3.94 ± 5.56

3.70 ± 4.92

4.96 ± 7.65

0.20 (0.03, 0.36)

0.006

Gender (n, %)

     

0.04 (-0.12, 0.19)

0.619

Male

456 (45.97%)

360 (45.57%)

96 (47.52%)

   

Female

536 (54.03%)

430 (54.43%)

106 (52.48%)

   

Race (n, %)

     

0.16 (0.01, 0.32)

0.109

Other

185 (18.65%)

138 (17.47%)

47 (23.27%)

   

Non-Hispanic White

642 (64.72%)

523 (66.20%)

119 (58.91%)

   

Non-Hispanic Black

165 (16.63%)

129 (16.33%)

36 (17.82%)

   

Education (n, %)

     

0.36 (0.21, 0.52)

< 0.001

Less than 12 grades

200 (20.18%)

136 (17.22%)

64 (31.84%)

   

High school graduate

198 (19.98%)

158 (20.00%)

40 (19.90%)

   

Some college

302 (30.47%)

255 (32.28%)

47 (23.38%)

   

College graduate above

291 (29.36%)

241 (30.51%)

50 (24.88%)

   

Marital status (n, %)

     

0.27 (0.11, 0.43)

0.003

Married

555 (56.17%)

462 (58.56%)

93 (46.73%)

   

Widowed or divorced

300 (30.36%)

220 (27.88%)

80 (40.20%)

   

Other

133 (13.46%)

107 (13.56%)

26 (13.07%)

   

Sleep disorder (n, %)

     

0.16 (0.03, 0.34)

0.046

Yes

371 (37.40%)

308 (38.99%)

63 (31.19%)

   

No

620 (62.50%)

482 (61.01%)

138 (68.32%)

   

History of stroke (n, %)

     

0.24 (0.09, 0.40)

< 0.001

Yes

84 (8.48%)

55 (6.97%)

29 (14.43%)

   

No

906 (91.52%)

734 (93.03%)

172 (85.57%)

   

CHF (n, %)

     

0.30 (0.14, 0.46)

< 0.001

Yes

69 (6.98%)

41 (5.20%)

28 (13.93%)

   

No

920 (93.02%)

747 (94.80%)

173 (86.07%)

   

Leisure time physical activity (n, %)

     

0.56 (0.40, 0.71)

< 0.001

Inactive

663 (66.83%)

490 (62.03%)

173 (85.64%)

   

Active

329(33.17%)

300(37.97%)

29 (14.36%)

   

Depression (n, %)

     

0.22 (0.06, 0.38)

0.004

No

827 (86.69%)

681 (88.21%)

146 (80.22%)

   

Yes

127 (13.31%)

91 (11.79%)

36 (19.78%)

   

Polypharmacy (n, %)

     

0.37 (0.21, 0.53)

< 0.001

< 5

500 (56.63%)

421 (60.49%)

79 (42.25%)

   

>=5

383 (43.37%)

275 (39.51%)

108 (57.75%)

   
CHF: Congestive Heart Failure

Baseline characteristics between low handgrip strength and normal handgrip strength.

Overall, cancer patients with low handgrip strength were more likely older, had poor sleep, and were less likely to participate in physical activity. In addition, the proportions of depression and polypharmacy were higher in cancer patients with low handgrip strength as compared to those with normal handgrip strength. Those patients who suffered a history of stroke or congestive heart failure tended to have low handgrip strength.(Table 1)

Univariate Analysis For The Factors Related To Depression

The results of univariate analysis showed that female, low handgrip strength, sleep disorder, stroke, and polypharmacy were associated with depression. In addition, cancer patients who were not married were more likely to have a risk of depression. Other related variables with depression were displayed in Table 2.

Table 2

Comparison between depression and non-depression.

Variables

Statistics

Depression

P-value

Gender (n,%)

     

Male

456 (45.97%)

1.0

 

Female

536 (54.03%)

1.64 (1.11, 2.42)

0.0123

AGE

64.75 ± 14.02

0.97 (0.96, 0.98)

< 0.0001

Race (n,%)

     

Other

185 (18.65%)

1.0

 

Non-Hispanic White

642 (64.72%)

0.60 (0.37, 0.95) 0.0309

0.0309

Non-Hispanic Black

165 (16.63%)

1.17 (0.67, 2.05) 0.5726

0.5726

Diagnosis (n,%)

     

Others

206(20.89%)

1.0

 

Skin

222(22.52%)

0.84 (0.46, 1.55)

0.5834

Prostate

138(14.00%)

0.84 (0.41, 1.68)

0.6146

Melanoma

64(6.49%)

1.04 (0.44, 2.46)

0.9229

Lung

27(2.74%)

0.28 (0.04, 2.17)

0.2242

Gynecological

117(11.87%)

1.82 (0.98, 3.38)

0.0589

Colon

55(5.58%)

1.25 (0.53, 2.97)

0.6108

Breast

157(15.92%)

1.28 (0.69, 2.36)

0.4395

Low handgrip strength (n,%)

     

No

790 (79.64%)

1.0

 

Yes

202 (20.36%)

1.85 (1.21, 2.82)

0.0048

Education (n,%)

     

Less than 12 grades

200 (20.18%)

1.0

 

High school graduate

198 (19.98%)

0.69 (0.40, 1.18)

0.1766

Some college

302 (30.47%)

0.68 (0.42, 1.09)

0.1109

College graduate above

291 (29.36%)

0.27 (0.15, 0.49)

< 0.0001

Marital status (n,%)

     

Married

555 (56.17%)

1.0

 

Widowed or divorced

300 (30.36%)

2.30 (1.51, 3.52)

0.0001

Other

133 (13.46%)

3.02 (1.80, 5.05)

< 0.0001

Sleep disorder (n,%)

     

Yes

371 (37.40%)

1.0

 

No

620 (62.50%)

0.27 (0.18, 0.40)

< 0.0001

History of stroke (n,%)

     

Yes

84 (8.48%)

1.0

 

No

906 (91.52%)

0.40 (0.23, 0.68)

0.0008

CHF (n,%)

     

Yes

69 (6.98%)

1.0

 

No

920 (93.02%)

0.59 (0.31, 1.12)

0.1051

Leisure time physical activity (n,%)

     

Inactive

744 (75.00%)

1.0

 

Active

248 (25.00%)

0.85 (0.55, 1.33)

0.4815

Polypharmacy (n,%)

     

<5

500 (56.63%)

1.0

 

>=5

383 (43.37%)

2.43 (1.62, 3.64)

< 0.0001

CHF: Congestive Heart Failure

The association between handgrip strength or low handgrip strength and the risk of depression.

Multivariable logistic regression analysis was used to identify the association between handgrip strength or low handgrip strength and depression among cancer patients. the results showed that handgrip strength was a protective factor for depression in an unadjusted model, the OR being 0.979(95%CI:0.966–0.992; P = 0.005). After adjusting potential confounding factors, this association was still exited (OR = 0.977,95%CI:0.960–0.994; P = 0.01). When handgrip strength was classified into low handgrip strength and normal handgrip strength, the multivariable logistic regression analysis also indicated that cancer patients with low handgrip strength had increased risk of depression after adjusting age, gender, marital status, sleep disorder, physical activity, history of stroke and polypharmacy (OR = 2.11,95%CI:1.19–3.73; P = 0.001).(Table 3)

Table 3

multivariable logistic regression analysis for the association between handgrip strength or low handgrip strength and the risk of depression.

Exposure

Non-adjusted

Adjust

Depression

   

Lower handgrip strength

   

NO

1.0

1.0

Yes

1.845 (1.206, 2.823)

0.0047

2.11 (1.19, 3.73) 0.01

Depression

   

Handgrip strength(kg)

0.979(0.966, 0.992)

0.005

0.977(0.960,0.994) 0.01

Restults: β (95%CI) Pvalue / OR (95%CI) P-value
Non-adjusted model adjust for: None
Adjust model adjust for: age, BMI, marital status, race, education, sleep disorder, history of stroke; pharmacology

Non-linear Relationship Analyses

The generalized additive model (GAM) analysis was adopted to detect whether there is a non-linear relationship between handgrip strength and depression and the results suggested the association between handgrip strength and the risk of depression was negative, meaning that with the increase of handgrip strength, the possibility of depression was decreased. (Shown in Fig. 1)

Subgroup analysis between low handgrip strength and depression in terms of different variables.

The subgroup analysis showed that the association between low handgrip strength and depression among cancer patients was almost unchanged in various stratum, indicating that this was reliable and stable (Fig. 2)

Discussion

This present study showed that cancer patients with low handgrip strength had an increased risk of depression as compared to those with normal handgrip strength, implying cancer patients need to take measures such as resistance training and nutritional program to improve handgrip strength, eventually reducing the risk of depression among cancer patients.

To the best of our knowledge, this is the first study to explore the association between handgrip strength and depression among cancer survivors. Many studies had examined the association between handgrip and depression among the community-dwelling population. In a cross-sectional study consisting of 24,109 Chinese adults (41. 5 ± 11.9 years), the authors found that participants with higher handgrip strength were associated with lower risk of depression and this association was particular in female21. Furthermore, another prospective cohort study conducted in rural Chinese populations, reporting the reversely association between handgrip and depression22. Our study was in line with these abovementioned previous studies. However, most of these studies were performed among relatively healthy people. Only a few studies focused on hospitalized patients. A study in 2020 was reported this association among participants suffering from different chronic diseases with inconsistent results23. The results found that those participants with high strength tertile had decreased depression both among people with no disease or metabolic diseases; however, this association was not observed in patients with arthritis diseases, which need more study for further exploration. Our study focused on a special population, cancer survivors, which are prevalent of suffering from depression24. Additionally, co-morbid depression had an adverse impact for treatment and recovery for cancer patients. Therefore, early prevention and treatment for depression were essential for cancer survivors.

Prior studies mainly focused on other aspects of risk factors for depression, which consisting of social factors (family, social support, stressful life event), characteristic of cancer (type of cancer, recurrence, prognosis), cancer treatment (radiotherapy, chemotherapy, treatment burden), individual characteristics (age, gender, marital status) and psychological response to diagnosis. To the best of our knowledge, no study explores the handgrip strength, a modifiable parameter, with the association of depression. Obviously, handgrip strength had many merits, simple, convenient, and not time-consuming, compared to these abovementioned factors, which were widely used in clinical settings and other primary community healthcare25. The most significant merit is that handgrip strength can be modified by interventions. Given our study indicated that lower handgrip strength increased the risk of depression (OR = 2.31,95%CI:1.37–3.89; P = 0.001), it is reasonable that improvement of handgrip strength by multiple measures such as resistance training program and national intervention can had benefit for reducing the risk of depression, which had a positive impact for cancer treatment and recovery. In a randomized controlled trial, the author reported that aerobic exercise intervention increased the amount of muscle mass among patients with major depression, which was beneficial for improving depression26.

The mechanism between low handgrip strength and depression was complicated. First, low handgrip strength as the core component for defining sarcopenia, which was reported by multiple studies27, 28, was associated with a high risk of depression. Second, cancer patients with low handgrip strength are unlikely to participate in physical activity. In this present study, cancer survivors with low handgrip strength experienced a higher proportion of inactive than those with normal handgrip strength (85.64% versus 62.03%). Given recent meta-analysis covering 97 randomized controlled trials reporting that exercise program was associated with a lower level of depression with the pooled OR = 2.24(95%CI:1.77–2.84)29. Therefore, cancer patients with low handgrip strength, hardly participating in physical activity would not gain the beneficial effect for reducing depression producing by exercise. Third, some studies reported that a muscle–brain crosstalk can be medicated by myokines and metabolites, which were secreted by muscle, playing a role in regulating hippocampal function that was closely related to depression11, 30. Although there were some possible reasons for the association between low handgrip strength and depression, future studies were warranted to explore this underlying mechanism.

This study possessed strengths and drawbacks. First, based on our knowledge, this is the first study to examine the association of handgrip strength and depression among cancer survivors, which was a fundamental issue for the prevention and management of depression among oncology Patients. Second, our study suggests that by using a simple and convenient dynamometer to measure handgrip strength, clinicians can identify the high-risk group of depression. Given the characteristic of modification of handgrip strength, appropriate and personalized exercise and nutritional programs are beneficial for reducing the risk of depression. Third, our study used comprehensive statistical analysis such as Lasso regression, by using shrinkage, to better select variables for minimizing multicollinearity. However, some drawbacks need to be mentioned. First, the feature of cross-section study limited the ability to identify a completely causal association, which needs more prospective cohort study for further exploration. Secondly, the NHANES study database did not provide some other important information about cancer treatment (radiotherapy and chemotherapy), length of time of first cancer diagnosis, and advanced disease stages, which might overestimate or underestimate the association between low handgrip strength and depression. Our study indicated that cancer survivors with low handgrip strength had an about 2.1-fold risk of depression, implying that clinicians need to perform corresponding interventions (physical activity and nutrition) to improving handgrip strength with the benefit for reducing depression.

Abbreviations

LASSO: Least Absolute Shrinkage and Selection Operator; PHQ-9: Patient Health Questionnaire; HANES: National Health and Nutrition Examination Survey; CHF: Congestive Heart Failure

LASSO

Least Absolute Shrinkage and Selection Operator

PHQ-9

Patient Health Questionnaire

HANES

National Health and Nutrition Examination Survey

CHF

Congestive Heart Failure

Declarations

Ethics approval and consent to participate

This study included data from NHANES 2011-14, all the participants agreed with this study and signed written informed consent, approving by the National Center for Health Statistics research ethics review board.

Consent for publication

Not Applicable

Consent to participate 

Not applicable

Availability of data and materials

Data that support the findings of this study are available NHANES, https://www.cdc.gov/nchs/nhanes/index.htm 

Competing interests

The authors declare that they have no competing interests

Funding

This work was not supported by any funding.

Acknowledgments

The authors thank the support of staffs from Peking Union Medical College Hospital and Donghua Hospital of Dongguan.

Authors' contributions

XMZ and ZBZ were responsible for drafting the manuscript 

XJW and WC were responsible for the concept and design 

XMZ and ZBZ participated in data analysis. 

All the authors have read and approved the manuscript.

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