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| ORIGINAL ARTICLE |
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| Year : 2023 | Volume
: 2
| Issue : 2 | Page : 72-78 |
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The association of visceral adiposity with handgrip strength in community dwellers of the United Arab Emirates
Ahmad Alli Alshouraa1, Ahmed Mohammad Darweesh1, Yazan Mazen Yaser1, Eelaf Wael Abazid1, Alya Kattarah Alshamsi1, Samah Mohamed Kannas1, Mohamad Abbara1, Ahmad Haitham Otour1, Rizwan Qaisar2, Amna Khalid3
1 Department of Basic Medicine, Basic Medical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
2 Department of Basic Medicine, Basic Medical Sciences, College of Medicine, University of Sharjah; Department of Family and Community Medicine and Behavioral Sciences, Sharjah Institute for Medical Research, University of Sharjah, Sharjah, United Arab Emirates
3 Department of Family and Community Medicine and Behavioral Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
| Date of Submission | 06-Oct-2022 |
| Date of Decision | 20-Dec-2022 |
| Date of Acceptance | 22-Dec-2022 |
| Date of Web Publication | 21-Feb-2023 |
Correspondence Address:
Dr. Amna Khalid
Department of Family and Community Medicine and Behavioral Sciences, College of Medicine, University of Sharjah, Sharjah
United Arab Emirates
 Source of Support: None, Conflict of Interest: None
DOI: 10.4103/abhs.abhs_54_22
Background: Handgrip strength (HGS) is a powerful tool to assess generalized body health; however, its association with visceral adipose tissues (VATs) in the community dwellers of the United Arab Emirates (UAE) is not known. The objectives of this study were to investigate the association between HGS and VATs in the UAE population of both genders, 18–65 years of age (n = 1146).
Methods: This is a cross-sectional study conducted in various community centers of the UAE from June to October 2021. We used a handgrip dynamometer to measure HGS and a bioelectrical impedance scale to measure body composition, including VAT content. VAT was categorized into low (1–9), optimal (10–14), and high (15–30) levels. We used t-test and ANOVA analyses to measure differences in HGS and VAT across gender and age groups.
Results: The peak HGS was found in the third and fourth decades of life, followed by an age-associated decline. We report that the highest HGS for dominant was found in people with the optimal VATs content irrespective of gender and age. Conversely, having low or high VATs was associated with lower HGS. However, there were no differences between the HGS of dominant versus nondominant hands in men and women.
Conclusion: Altogether, we report an association of an optimal VAT content with peak HGS, so that having low or high VATs were associated with reduced HGS. Taken together, the measurements of VAT and HGS may be helpful in assessing generalized health in preclinical settings.
Keywords: Gait speed, handgrip strength, skeletal muscle, visceral adipose tissue
How to cite this article:
Alshouraa AA, Darweesh AM, Yaser YM, Abazid EW, Alshamsi AK, Kannas SM, Abbara M, Otour AH, Qaisar R, Khalid A. The association of visceral adiposity with handgrip strength in community dwellers of the United Arab Emirates. Adv Biomed Health Sci 2023;2:72-8 |
How to cite this URL:
Alshouraa AA, Darweesh AM, Yaser YM, Abazid EW, Alshamsi AK, Kannas SM, Abbara M, Otour AH, Qaisar R, Khalid A. The association of visceral adiposity with handgrip strength in community dwellers of the United Arab Emirates. Adv Biomed Health Sci [serial online] 2023 [cited 2023 Jun 9];2:72-8. Available from: http://www.abhsjournal.net/text.asp?2023/2/2/72/370105 |
| Background | |  |
Muscle strength is a critical predictor of systemic health and is associated with mortality and morbidity due to multiple diseases.[1] The predictive potential of muscle strength is independent of muscle mass, comorbidities, and systemic inflammation.[2] Handgrip strength (HGS) is a standard tool to assess muscle quality.[3] Multiple studies indicate that a greater HGS is associated with improved health and a lower risk of all-cause mortality.[1] In this context, HGS has been proposed as a screening tool to evaluate functional independence and systemic health before more specified tools are applied. HGS of the dominant hand is usually stronger than the nondominant hands, although the literature is not very consistent on this.[4] Since HGS may partly be dictated by ethnicity, normative values of HGS are suggested for various populations.[5] However, such values for the United Arab Emirates (UAE) population of young to middle age are lacking.
Obesity is considered a risk factor for several systemic diseases, including metabolic syndrome.[6] There is also increasing evidence of increased mortality and morbidity in patients with increased body fat content.[6] Body mass index (BMI) is a routinely used tool for measuring obesity. However, it ignores body fat distribution and may not accurately assess the obesity phenotype. In addition, people are not homogeneous in their body fat distribution, and the amount of subcutaneous and visceral adipose tissues (VATs) may differ across people with the same BMI.[7] Among different body fats, VATs have emerged as an important risk factor for multiple diseases.[8] VATs are metabolically highly active, and their overproduction is associated with insulin resistance, hypertension, atherosclerosis, and other diseases in the community-dwelling adult population. However, recent evidence suggests that not all obese individuals develop a metabolic phenotype. A “healthy obesity'' phenotype has been suggested so that an optimal amount of body fat may be protective against systemic diseases.[2] However, the amount of VATs driving the obesity paradox is not well defined. In addition, the amount of VATs is sexually dimorphic and varies with age.[7] Therefore, an age- and gender-specific characterization of optimal VATs is required to maintain normal health.
An inverse interface between HGS and abdominal fat content has been suggested so that higher abdominal fat is associated with lower HGS.[8] In addition, sexual dimorphism is suggested, with men having more VATs than women.[9] Aging is also associated with the gradual accumulation of VATs.[10] These factors may partly dictate the association between VATs and HGS. In addition, the “healthy obesity'' phenotype suggests an optimal amount of VATs maintain normal HGS and adequate body health. However, the quantification of VATs and their association with HGS in an age- and gender-specific manner is lacking. In addition, the normative values for HGS vary across countries,[11] necessitating the studies focusing on distinct geographical regions. To our knowledge, only one study has evaluated HGS in the UAE population.[12] However, this study did not investigate the body composition, including VAT content, among the recruited participants. Therefore, it remains to be seen if VAT and HGS exhibit a potential interface among the residents of the UAE.
The purpose of this study is multifold: (1) To define the reference HGS values of young- and middle-aged community dwellers of the UAE in an age- and gender-specific manner, (2) To compare the HGS of dominant versus nondominant hands in the same population. (3) To investigate the potential association between VATs and HGS in the UAE population. We hypothesize that HGS is partly affected by the age, gender, and dominance of hands. In addition, a potential association between HGS and VATs may exist so that a greater HGS is associated with an optimal amount of VATs. Considering that HGS and VAT can be measured in any clinical setting cost-effectively without requiring technical expertise, our study may have been useful as an early evaluation tool of generalized health before the more rigorous and detailed clinical assessment is applied.
| Materials and Methods | | |
A cross-sectional design was used to recruit a sample of 1146 participants. The UAE population was recruited through a convenience sampling technique. Ethics approval was taken from the University of Sharjah (Reference number: REC-21-06-14-02-S). Only participants who could speak English or Arabic were included in the study sample. People with disabilities/deformities or those who practice HGS exercise regularly were excluded. The data were collected at public places, and the participation was completely voluntary. All participants provided written informed consent, after obtaining information about the study protocol, data handling, privacy, and the research investigators. The study was conducted from June to October 2021. All participants were of Arab or South Asian ethnicities. Participants were either UAE citizens or residents with adequate literacy to understand the study. Most participants in the youth age group were medical students at the University of Sharjah. Kaptein's guidelines were followed to calculate the sample size used for fixed populations.[13]
Demographics characteristics
A self-report questionnaire was provided to the participants asking for information about demographics. The age of the participants was categorized into youth (18–29 years), young adults (30–39 years), middle adults (40–49 years), and late adults (50+).
Handgrip strength measurement
A digital handgrip dynamometer (CAMRY, South El Monte, CA, USA) was used to measure HGS as described elsewhere.[14],[15] The participants were asked to flex their elbows at a 90° angle while seated while holding the digital dynamometer in the supine position. They were then instructed to squeeze the dynamometer with all their strength smoothly. Rapid jerking or wrenching was avoided. Participants were asked not to move otherwise during the process. The procedure was repeated thrice for each hand with a 1-min resting interval. The highest value observed was taken as the final measure of HGS.
Body composition analysis
Body composition, including VATs content, was analyzed using a bioelectrical impedance scale (RENPHO, Dubai, UAE), as described previously.[16] VATs were categorized into low (1–9), optimal (10–14), and high (15–30), as described elsewhere.[17]
Data analysis
Data were analyzed using the Statistical Package for the Social Science SPSS, version 24 (IBM Corp., Armonk, NY, USA). Mean values, standard deviations, and percentages are presented for the data across genders and age groups. Data were analyzed for missing values and normal distribution. T-test and ANOVA analyses were used to measure differences in HGS and VAT across gender and age groups.
| Results | | |
Among the study participants, 740 (64.6%) participants were male, 372 (32.5%) were female, and 34 participants did not disclose their gender. Out of 1146 participants, 1080 (94.2%) had a dominant right hand. Three hundred (26.2%) participants were between ages 18 and 29 years, 328 (28.6%) were between ages 30 and 39, 300 (26.2%) were 40 and 49 years old, and 180 (15.7%) were 50 + years of age. The overall mean for HGS for the dominant hand was higher than for the nondominant hand. We performed t-test to measure gender differences in dominant and nondominant HGS. [Table 1] shows a statistically significant difference across gender, with higher mean scores in men versus women.
A Chi-square analysis was performed to estimate gender differences in VAT content. Significant differences were found in VAT between males and females [Table 2]. Most females had low VATs with χ2 = 134.87, P < 0.01.
[Figure 1] shows group differences in means of dominant and nondominate HGS across age groups and gender. Those between the ages of 30 and 39 years score highest on HGS, while 50+ years old score lowest [Figure 1]. The ANOVA analysis shows that overall group differences were statistically significant in males [Table 3]. Tukey's postanalysis reveals that males 50+ years old scored significantly lower than any other age category, followed by middle adults. In the female sample, age differences were insignificant for the dominant hand but significant for the nondominant hand grip strength. However, no statistically significant differences were observed between groups in Tukey post hoc comparisons. | Figure 1: HGS by age and gender (n = 1146). HGS: Handgrip strength. (a) dominant HGS by age in males, (b) non-dominant HGS by age in males, (c) dominant HGS by age in females, (d) non-dominant HGS by age in females.
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 | Table 3: Mean differences on handgrip strength across age groups and gender using ANOVA analysis (n=1146)
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[Figure 2] shows group differences in means of dominant and nondominate HGS across VAT levels and sexes. The ANOVA analysis shows that the overall group difference for dominant hand was statistically significant in males but insignificant in females [Table 4]. Tukey's postanalysis reveals that those with low visceral fat levels 1–9 showed a lower mean on dominant HGS than those with optimal (10–14) VAT levels. For the nondominant hand in males, the grip strength was lower for the low VAT group than the optimal group. Group difference with high VAT levels was statistically insignificant. | Figure 2: HGS by gender and VAT (n = 1146). HGS: Handgrip strength, VAT: Visceral adipose tissues. (a) dominant HGS by VAT in males, (b) dominant HGS by VAT in females, (c) non-dominant HGS by VAT in males, (d) non-dominant HGS by VAT in females.
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 | Table 4: Mean differences on handgrip strength across levels of VAT and gender using ANOVA analysis (n=1146)
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| Discussion | | |
In this cross-sectional study, we investigated the HGS and VAT content of the community-dwelling population of the UAE. We report that the highest HGS was found in people with the optimal VATs content irrespective of gender and age. Conversely, having low or high VATs was associated with lower HGS. The peak HGS was found in the third and fourth decades of life, followed by an age-associated decline. However, there was no significant difference between the HGS of dominant versus nondominant hands.
Several studies use muscle mass as an indicator of systemic health.[18] Although HGS is partly dictated by muscle mass, it has emerged as a superior prognostic marker of mortality and morbidity than muscle mass.[18],[19] In addition, the cost-effective and user-friendly nature of measuring HGS makes it a reliable tool for assessing generalized health in preclinical settings.[15] Consistent with previous studies, the peak HGS was found in the third and fourth decades of life.[20] However, this effect was more prominent in men, who maintained their HGS throughout the third and fourth decades of life. Conversely, the peak HGS was attained during the fourth decade of life only in women. These findings are generally consistent with the literature and indicate the onset of the sarcopenic process by the later years of the fourth decade of life.[21]
We did not find a significant difference between the HGS of dominant and nondominant hands, irrespective of age and gender. However, a slightly lower HGS of the nondominant hand agrees with previous findings and potentially reflects the reduced activity of the nondominant hand. This finding is supported by a plethora of literature showing a positive association between physical activity and muscle strength.[22],[23],[24],[25]
Our data indicate that the highest HGS was found in participants with optimal VATs. Conversely, the lower or higher than optimal VAT content was associated with reduced HGS in both genders. Visceral obesity and elevated VATs content has several pathological effects on multiple body organs, including skeletal muscle.[26] VATs release several pro-inflammatory cytokines into circulation, resulting in chronically elevated inflammation.[27] The detrimental effects of inflammation on skeletal muscle mass and strength are well recognized.[28] Specifically, the patients with elevated circulating inflammatory cytokines exhibit reduced muscle strength and mass.[29] Several mechanisms are suggested for inflammation-induced muscle loss. For example, inflammatory cytokines are associated with reduced muscle protein synthesis and elevated muscle protein degradation, which contribute to muscle atrophy.[30] In addition, inflammation also triggers the activation of apoptotic pathways, resulting in atrophy and degeneration of muscle fibers.[31] Consistent with these findings, an upregulation of markers of atrophy and downregulation of markers of protein synthesis are reported in skeletal muscle with heightened inflammation.[32] These findings are consistent with our reports of reduced HGS in participants with elevated VATs contents.[33] To our surprise, we also found reduced HGS in participants with lower than optimal VAT content. However, an optimal amount of body fat depots, including VATs, are required for the normal functioning of the body. Conversely, selective dysregulation of VATs can induce multiple pathologies, including skeletal muscle weakness and reduced HGS.[34]
Our study supports the notion that maintaining muscle strength is critical for avoiding physical and functional limitations in patients with obesity.[22] Specifically, obese patients with reduced HGS demonstrate functional limitations in the activities of daily living and progressively adopt a dependent lifestyle.[22] These findings indicate that the interventions aimed at preserving or boosting muscle strength may be critical in preventing the generalized decline in health in patients with obesity or reduced VAT content.
Our study may be helpful in preclinical settings to evaluate generalized health before the clinically relevant diseases set in. For example, the measurements of VATs and HGS can predict adverse cardiac outcomes, including coronary artery diseases in the community-dwelling population.[2] Similarly, HGS and VATs content are related to mortality and morbidity due to several diseases.[1],[35]
| Conclusion | | |
Altogether, we report an interface between optimal VAT content and peak HGS among the community dwellers of the UAE. Conversely, a higher or lower VAT content was associated with reduced HGS. Among different age groups, the peak HGS was observed in the fourth decade of life, followed by a decline with advancing age. The measurements of VAT and HGS may help assess generalized health in preclinical settings. Future studies should dissect the mechanistic associations between HGS and VAT content in an age-and gender-specific manner. In addition, it may be pertinent to investigate if the potential association between HGS and VAT is affected by age-associated chronic ailments. While HGS is a globally recognized measure of muscle strength, an evaluation of quadriceps strength may be more relevant to the activities of daily living and a dependent lifestyle.[36] Finally, the laboratory measurements of circulating markers of inflammation may establish a more direct association between HGS and VAT.
Study limitations
The strength of our study is the large population size and the detailed demographic profiling of the study cohort. The unique context of the UAE population also adds to the study. The study may also help define normative values of HGS for the UAE population. However, this study has certain limitations. We could not determine the causal relationship between VAT and HGS in the study population. The study is cross-sectional in nature, so the predictive potential of VAT in HGS should be cautiously interpreted. The study was conducted in public places, so nonambulant people were not included. It is possible that some study participants may have diagnosed or undiagnosed chronic diseases, which may affect our findings. We did not investigate the levels of physical activity of the study participants, which may affect HGS and VAT independently of each other.
Acknowledgments
We thank you the study participants for taking part in this research.
Authors' contributions
RQ and AK conceived the research concept, RQ and AK developed research design, AA, AD, YZ, EA, AA, SQ, MA, AH, performed field work and data analysis; RQ, AK, AA, AD, YZ, EA, AA, SQ, MA, AH, performed the formal analysis, AA, AD, YZ, EA, AA, SQ, MA, AH, RQ and AK, prepared the first draft and all reviewers reviewed and approved final draft of the manuscript. All authors are responsible for the contents and integrity of this manuscript.
Ethical statement
Ethics approval for this study (REC-21-06-14-02-S) was obtained from the research ethics committee at the College of Medicine, University of Sharjah.
Financial support and sponsorship
This work was supported by University of Sharjah Competitive Grants (2001090177 and 22010901121).
Conflict of interests
No conflict of interests declared.
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[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4]
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