Association between Dynapenia and Multimorbidity in Community-Dwelling Older Adults: A Systematic Review

Dynapenia and Multimorbidity

Article information

Ann Geriatr Med Res. 2024;28(3):238-246

Publication date (electronic) : 2024 April 24

doi : https://doi.org/10.4235/agmr.24.0007

Hironori Ohinata

, Shan Yun , Naoko Miyajima , Michiko Yuki

Faculty of Health Sciences, Hokkaido University, Sapporo, Japan

Corresponding Author Hironori Ohinata, PhD Faculty of Health Sciences, Hokkaido University, N12-W5, Kitaku, Sapporo 060-0812, Japan E-mail: hinata@hs.hokudai.ac.jp

Received 2024 January 10; Revised 2024 April 3; Accepted 2024 April 16.

Abstract

Dynapenia and multimorbidity are common health problems affecting older adults. However, few studies have systematically reviewed the association between dynapenia and multimorbidity. Therefore, this systematic review aimed to provide a comprehensive overview of studies on the association between these conditions. We searched four electronic databases for relevant articles published in July 2023. The main inclusion criteria were the following: a description of dynapenia, which indicates loss of muscle strength, and a description of multimorbidity with two or more chronic diseases. Five studies met these inclusion criteria. In all five of these studies, the participants were community-dwelling older adults. All the studies showed an association between dynapenia and multimorbidity. The prevalence of dynapenia and multimorbidity ranged from 16% to 25.9%. The results of our systematic review demonstrated that dynapenia in older adults increases the risk of multimorbidity. We propose that interventions and reversible changes in dynapenia can prevent multimorbidity. (PROSPERO Registration No. CRD42023443282)

Keywords: Dynapenia; Multimorbidity; Multi disease; Older adults; Systematic review

INTRODUCTION

The world's aging population is rapidly increasing, and it is expected to reach 16.4% by 2050, posing a societal challenge.1) The physical changes associated with aging are categorized into sarcopenia and dynapenia.2) Sarcopenia is defined as a decrease in skeletal muscle mass, muscle strength, or physical performance,3,4) whereas dynapenia is defined as a loss of muscle strength despite a normal skeletal muscle mass.5) Dynapenia impairs physical function, leading to reduced physical activity and impaired mobility.6) Dynapenia development involves the transmission of cerebral excitability and age-related changes, which suggests that sarcopenia and dynapenia may be conceptually distinct.7,8) Furthermore, dynapenia reduces quality of life and increases mortality risk.9,10) In some cases, dynapenia can also coexist with chronic diseases, such as diabetes, cancer, and dementia, affecting health outcomes and worsening symptoms.11-13)

The presence of two or more chronic diseases is commonly called multimorbidity.14) Multimorbidity increases with age and is associated with the increased use of inpatient and outpatient care and high mortality rates.15) A previous systematic review showed that the prevalence of multimorbidity in older adults ranges from 55% to 98%.16) Consequently, many older adults with multimorbidities have negative health outcomes. Additionally, although most healthcare provisions and medical research to date have focused on individual diseases, a multidimensional approach is essential for older adults with multimorbidities.17) As a multidimensional approach, healthcare providers should promote understanding and provide better support for diseases to reduce the burden of treatment, polypharmacy, and polyphysician.18,19)

However, to our knowledge, no systematic reviews have investigated the association between dynapenia and multimorbidity. The concept of dynapenia is similar to that of frailty. Dynapenia focuses on the loss of muscle strength with aging.2) whereas frailty describes the decline in physical, cognitive, and social functions with aging, indicating overall physical and psychological vulnerability.20) A review of frailty and multimorbidity in older adults found that 70% of frail older adults have multimorbidity, suggesting an interaction between the two factors.21) In their review of sarcopenia and comorbidity, Pacifico et al.22) reported that patients with cardiovascular and respiratory diseases, dementia, and diabetes developed sarcopenia more frequently, compared with patients without these conditions. Thus, the relationships and characteristics of age-related conditions and multimorbidity in older adults have been demonstrated.21,22) Therefore, we aimed to review the association between dynapenia and multimorbidity and consider potential medical interventions for adults with these two conditions.

MATERIALS AND METHODS

This systematic review was guided by an a priori defined protocol consistent with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.23) The protocol for this systematic review was registered with PROSPERO (ID: CRD42023443282). The electronic databases searched included PubMed, EBSCO CINAHL, Cochrane Library (Wiley), and Web of Science for relevant articles published through July 7, 2023. The search strategy was created in consultation with a medical librarian, using search terms that primarily included derivatives of the terms: dynapenia and multimorbidity. Supplementary Table S1 presents the PubMed search strategy.

H.O. searched for articles, and all results from the complete search were imported into Rayyan online software for screening and reading.24) H.O. and S.Y. independently assessed the titles and abstracts of the studies identified through the search of electronic databases. If the title and abstract did not provide sufficient information to determine the eligibility of a study, the full text of the article was reviewed. H.O. and S.Y. then independently assessed the full texts of the articles to arrive at a final list of eligible articles. In case of any disagreement regarding inclusion during the screening of titles and abstracts or full-text evaluation of the articles, a third reviewer was consulted for making the final decision.

Eligibility Criteria

We included studies that (1) described dynapenia; (2) described multimorbidity with two or more chronic diseases; (3) were original articles written in English; and (4) were randomized controlled trials, cohort studies, observational studies, qualitative studies, or systematic reviews. The exclusion criteria were the following: (1) studies not investigating the association between multimorbidity and dynapenia; (2) protocols and case reports; and (3) studies not including human participants.

Data Extraction

Following the PRISMA guidelines, we recorded the number of articles retrieved, number of articles excluded, reasons for their exclusion, and number of articles included.23) We also created a data form to extract data relevant to the research question. H.O. independently extracted the data and S.Y. checked the extracted data. Any disagreements regarding the extracted data were discussed and resolved. We planned to perform a meta-analysis if we identified three or more studies with similar definitions of dynapenia and multimorbidity.

Quality Assessment

We assessed the risk of bias in the included studies using the Critical Appraisal Checklist for Analytical Cross-Sectional Studies from the Joanna Briggs Institute (JBI).25) The checklist comprised eight items with possible reviewer responses of "yes," "no," or "unclear." The sum of the number of "yes" responses was defined as the overall score for each study, which ranged from 0 to 8. We assigned the studies as having low, moderate, and high risk of bias based on "yes" scores >70%, between 50% and 69%, and <49%, respectively. We used RevMan 5.4 (The Cochrane Collaboration, https://training.cochrane.org/online-learning/core-software/revman) to generate our quality assessment results. The two reviewers independently examined the quality assessment process, checked the collected information, and discussed cases of disagreement.

RESULTS

The results of screening of the studies based on the eligibility criteria are shown in Fig. 1. This review included five studies.26-30) A summary of these five eligible studies is presented in Table 1. Four studies were conducted in Brazil26-29) and one in the United Kingdom.30) In all the included studies, the target population consisted of older community-dwelling adults.26-30) The number of participants differed between studies, ranging from 247 to 8,396.

Fig. 1.

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 flow diagram for dynapenia and multimorbidity.

Table 1.

Characteristics of included studies

A summary of the risk of bias assessment is shown in Fig. 2. Based on the criteria of the JBI Critical Appraisal Checklist for Analytical Cross-Sectional Studies, we ranked four of the five eligible studies as having a low risk of bias.26,28-30) One study was ranked as medium quality ("yes" score of 62.5%).27)

Fig. 2.

Assessment of risk of bias.

Table 2 summarizes the relationship between dynapenia and multimorbidity reported in the eligible studies. The criteria for dynapenia were mainly measured and assessed based on grip strength; however, the values differed between studies. For example, the grip strength of participants was classified into tertiles, with the lower third of ≤18 kg classified as dynapenia,29) or cutoffs of ≤27 kg for men and ≤16 kg for women.27,30) The prevalence of dynapenia tended to increase with age, with overall rates ranging from 11.1% to 17.2% in studies of participants aged ≥50 years and from 25.9% to 33.2% in studies of participants aged ≥60 years.

Table 2.

Criteria for dynapenia and multimorbidity and their associations

The multimorbidity criteria included studies that selected participants with hypertension and diabetes29) with two or more chronic diseases,26,27,30) including heart disease, stroke, and cancer, and five or more chronic diseases.28) The prevalence of multimorbidity ranged from 35.4% to 64.6%, depending on the age of the participants.

The association between dynapenia and multimorbidity was relevant in all five included studies.26-30) The prevalence of multimorbidity among participants with dynapenia ranged from 16% to 25.9%. Similarly, Borges et al.27) showed that the odds ratio for multimorbidity was 1.2-fold higher in participants with dynapenia than in those without dynapenia. Additionally, Montes et al.28) measured handgrip strength and the quartile criteria for dynapenia and showed that the prevalence of multimorbidity increased with decreasing handgrip strength. Komatsu et al.26) also showed that dynapenia, which indicates low muscle strength, is a mediating variable that leads to increased mortality in association with multimorbidity. To successfully conduct a meta-analysis, we required at least three studies with the same definitions for dynapenia and multimorbidity, respectively. Among the included studies, only two—those by Borges et al.27) and Veronese et al.30)—met this criteria; therefore, we could not perform a meta-analysis.

DISCUSSION

Our findings were as follows: (1) studies on dynapenia and multimorbidity were mainly cross-sectional studies in community settings; (2) participants with dynapenia were at a higher risk of multimorbidity; and (3) intervention studies on dynapenia and multimorbidity have not been reported.

Studies on dynapenia and multimorbidity have primarily been conducted in Brazil. In a study by Borges et al.27) on community-dwelling adults aged ≥50 years, almost one-fifth of them were found to have dynapenia. In recent years, the Brazilian Government has developed the Financial and Family Health Program as a strategy to address health promotion and disease prevention.31) The increasing prevalence of age-related disabilities and diseases is a global challenge and a topic of health promotion.32) Thus, research on dynapenia and multimorbidity is important in the current aging society. In their review, Komatsu et al.26) found that dynapenia increased the prevalence of multimorbidity, in a path analysis. In contrast, diseases found in older adults, such as dementia and cancer, can influence the prevalence of dynapenia.12,13) Therefore, future studies should longitudinally examine the changes in risk and the interactions between dynapenia and multimorbidity.

Interventions for patients with dynapenia and multimorbidity should include preventive measures. Dynapenia is a risk factor for multimorbidity.26) In our review, cross-sectional studies reported an increased risk of multimorbidity associated with dynapenia.26-28) Komatsu et al.26) demonstrated that dynapenia was a mediating variable in the increase in multimorbidity and subsequent mortality. Therefore, early medical interventions for dynapenia may prevent multimorbidity. Such interventions improve physical activity and muscle strength.33,34) For example, in an intervention study on dynapenia, a combined intervention of low-impact resistance training and protein intake improved muscle strength and homogeneity.34) Similarly, systematic reviews of interventions for sarcopenia and dynapenia have demonstrated the benefits of resistance training.33) We propose that dynapenia is a reversible condition and that medical interventions are likely to prevent the worsening of multimorbidity. Aoki et al.35) reported five patterns of multimorbidity, including the combination of skeletal and gastrointestinal diseases. For example, the loss of muscle mass in dynapenia can lead to knee osteoarthritis, and the use of nonsteroidal anti-inflammatory drugs for pain can lead to gastric ulcers.36) Thus, the treatment of musculoskeletal disorders may allow symptom control; however, the side effects of these drugs may lead to the occurrence of new comorbidities, resulting in multimorbidity. Additionally, muscle weakness in dynapenia can cause a negative cycle of poor physical function and nutrition.20) The key to breaking this negative cycle is a reversible change through interventions for muscle weakness in dynapenia.37) Improved muscle strength through medical interventions may contribute to the maintenance or improvement of physical activity. Therefore, screening for dynapenia among community-dwelling older adults to select those in need of intervention may prevent the risk of developing multimorbidity due to muscle weakness and maintain physical function.38) In the future, we must continue to evaluate the effects of early assessment and intervention on dynapenia in older adults.

However, a balancing model has been proposed as a useful way to intervene in multimorbidity.17,19) The balancing model aims to increase the understanding of the disease, social support, and resilience of the patient, as well as to reduce the multiple challenges of polypharmacy, polyphysician, and lifestyle, which can be burdens to treatment.18) Thus, medical interventions for adults with dynapenia and multimorbidity should include not only resistance training for dynapenia but also multimodal interventions. Additionally, multidisciplinary interventions can improve outcomes in older adults.39) However, none of the studies included in our systematic review involved medical interventions. Further research is warranted to investigate the effects of multidisciplinary interventions in communities.

Limitation

We conducted this systematic review to identify the relationship between dynapenia and multimorbidity and also considered medical interventions. However, this study has some limitations. First, most of the included studies used a cross-sectional design, and only one used a longitudinal design. Given this, we could not determine causal associations because of the lack of longitudinal evidence. Second, the definitions of dynapenia and multimorbidity were inconsistent across the included studies. Dynapenia is a condition in which both men and women experience age-related loss of muscle strength while maintaining muscle mass. The cutoff values for dynapenia were discussed and described using the cutoff values for sarcopenia. The European Working Group on Sarcopenia in Older People (EWGOSP2) criteria are a grip strength < 27 kg for men and < 16 kg for women and skeletal muscle mass < 7.0 kg/m² for men and < 5.5 kg/m² for women, based on bioelectrical impedance analysis.4) The Asian Working Group for Sarcopenia (AWGS 2019) criteria are a handgrip strength < 28.0 kg for men and < 18.0 kg for women and skeletal muscle mass < 7.0 kg/m² for men and < 5.7 kg/m² for women, based on bioelectrical impedance analysis.40) The studies included in this review used only the lower third of grip strength or loss of grip strength as the criteria for dynapenia, and the maintenance of muscle mass was unclear.26-30) Similarly, multimorbidity was often defined as the comorbidity of two or more chronic diseases27,29,30); however, one study defined it as the comorbidity of five or more chronic diseases.28) Therefore, although the impact of dynapenia may differ depending on the degree of multimorbidity, this relationship could not be considered in our review. The association between dynapenia and the degree of multimorbidity must be clarified in future studies. However, we systematically reviewed and defined the eligibility criteria and screened studies to clarify this relationship. Further research is warranted to establish a consensus definition of dynapenia and multimorbidity.

Conclusion

This systematic review identified an association between dynapenia and multimorbidity in five studies that met the eligibility criteria. All the selected studies involved community-dwelling older adults. Additionally, dynapenia increased the risk of multimorbidity in all the included studies. However, we found no intervention studies on dynapenia and multimorbidity. Further research is needed to establish the interaction between dynapenia and multimorbidity and the changes in prevalence with medical interventions.

Acknowledgements

The authors express their deepest gratitude to Moe Nemoto and Miyuki Sasaki of the Medical Sciences Group, Research Support Division, Hokkaido University Library for their help with the search strategy.

Notes

CONFLICT OF INTEREST

The researchers claim no conflicts of interest.

FUNDING

None.

AUTHOR CONTRIBUTIONS

Conceptualization, HO; Data curation, HO, SY; Investigation, HO, SY; Methodology, HO, SY; Writing_original draft, HO; Writing_review & editing, SY, NM, MY.

SUPPLEMENTARY MATERIALS

Supplementary materials can be found via https://doi.org/10.4235/agmr.24.0007.

Table S1.

Search strategies in PubMed

agmr-24-0007-Supplementary-Table-S1.pdf

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Table 1.

Characteristics of included studies

Author	Title	Year	Country	Study design	Objective	Location (e.g., hospital, community, etc.)	Number of participants	Inclusion and exclusion criteria
Komatsu et al.26)	Association of dynapenia, obesity and chronic diseases with all-cause mortality of community-dwelling older adults: a path analysis	2019	Brazil	Cross-sectional study	To evaluate the effect of dynapenia, central obesity and the presence of chronic diseases in 8-year mortality of community-dwelling older adults.	Community	610	Inclusion criteria: Seven thousand older adults over 65 years of age living in seventeen cities in five regions in Brazil.
Komatsu et al.26)		2019	Brazil	Cross-sectional study		Community	610	Exclusion criteria: Cognitive impairment with an mini-mental score of 17 or less, those who cannot be examined due to visual or hearing impairments, wheelchair users, and older adults with bedridden or terminal illnesses, those with missing physical measurement data, and those with external causes of the International Statistical Classification of Diseases and Related Health Problems 10th Revision.
Borges et al.27)	A nationwide study on prevalence and factors associated with dynapenia in older adults: ELSI-Brazil	2020	Brazil	Cross-sectional study	To assess the prevalence and factors associated with dynapenia in a nationally representative sample of Brazilians aged 50 years and older.	Community	8,396	Inclusion criteria: Persons over 50 years of age in 70 cities, towns, and villages in the five main regions in Brazil.
Montes et al.28)	Strength and multimorbidity among community-dwelling elderly from southern Brazil	2020	Brazil	Cross-sectional population-based study	To assess the association between multimorbidities and handgrip strength in older community-dwelling individuals from a city in southern Brazil, identifying potential differences according to sex and loss of muscle mass.	Community	1,336	Inclusion criteria: Persons 60 years of age or older residing in Pelotas in southern Brazil.
Montes et al.28)		2020	Brazil	Cross-sectional population-based study		Community	1,336	Exclusion criteria: Institutionalized individuals such as in hospitals, long-term institutions and prisons, or those with mental or physical disabilities.
Correa et al.29)	Association between dynapenic abdominal obesity and inflammatory profile in diabetic older community-dwelling patients with end-stage renal disease	2021	Brazil	Cross-sectional, analytical study	To investigate the association between dynapenic abdominal obesity and inflammatory markers in community-swelling elderly with end-stage renal disease.	Community	247	Inclusion criteria: 60 years, undergoing hemodialysis for at least 3 months, and three times per week, stable clinical condition in the last 3 months, and except for vascular access correction.
Correa et al.29)		2021	Brazil	Cross-sectional, analytical study		Community	247	Exclusion criteria: Recent acute myocardial infarction (within the past 3 months) or unstable angina, systemic lupus erythematosus, congenital kidney malformation or some autoimmune disease that affects the kidneys, and severe decompensated diabetes or severe neuropathy, retinopathy, or diabetic nephropathy.
Veronese et al.30)	Dynapenic abdominal obesity and incident multimorbidity: findings from the English longitudinal study on ageing	2023	Italy	Longitudinal study	To investigate the association between dynapenic abdominal obesity (DOA) at baseline and new onset multimorbidity over 10 years of follow-up.	Community	3,302	Inclusion criteria: Participants in Wave 2 and 7 of the Health Survey for England (HSE).
Veronese et al.30)		2023	Italy	Longitudinal study		Community	3,302	Exclusion criteria: Data on dynapenia were missing, data on waist circumference were missing, participants already had two or more diseases at baseline, and data on the onset of multimorbidity were not available.

Table 2.

Criteria for dynapenia and multimorbidity and their associations

Author	Title	Participant	Dynapenia criteria	Dynapenia prevalence	Multimorbidity criteria	Multimorbidity prevalence	Outcomes (association with multimorbidity/intervention effects)
Komatsu et al.26)	Association of dynapenia, obesity and chronic diseases with all-cause mortality of community-dwelling older adults: a path analysis	Older people aged ≥65 years living in urban areas	The “low muscle strength” (mean, 26 kg) category, or dynapenic, included participants whose average of three measurements for MS was among the 20% lowest distribution values of the sample, adjusted by sex and body mass index quartiles, as suggested by Fried et al.	-	Participants answered whether in the past year a doctor had diagnosed: heart disease (angina, myocardial infarction, heart attack); hypertension (high blood pressure); stroke; diabetes mellitus; cancer; arthritis; lung diseases (bronchitis, emphysema); depression; and osteoporosis. Answers were summarized as the total number of diseases, and categorized as none, 1–2 and ≥3.	The categories of number of diseases at baseline for 270 participants (44.3%) were 1–2 and for 269 participants (44.1%) were ≥3.	Mediator roles were "central obesity," "more disease" and dynapenia.
Komatsu et al.26)		Older people aged ≥65 years living in urban areas		-			Path analysis showed that muscle strength decreased with increasing age and less physical activity. It also showed that reduced muscle strength was associated with a number of more diseases, leading to increased mortality.
Borges et al.27)	A nationwide study on prevalence and factors associated with dynapenia in older adults: ELSI-Brazil	Participants aged 50 years and over living in five major regions	Dynapenia was defined as low muscle strength (<27 kg for men and <16 kg for women).	The overall prevalence of the target population was 17.2% (16.6% among men and 17.7% among women).	Multimorbidity was defined as the presence of two or more chronic diseases (versus one or none). The number of chronic diseases was defined through a history of medical diagnosis of the following diseases: hypertension, diabetes, chronic obstructive pulmonary disease, osteoarthritis, stroke, asthma, cancer, renal disease, or heart disease.	A total of 35.4% of all participants had multimorbidity.	In dynapenia, 22.4% (95% CI, 20.1–24.8) of participants had multimorbidity. The final logistic regression model results for factors associated with dynapenia showed that the odds ratio for dynapenia was higher when two or more diseases were associated with an odds ratio of 1.2.
Borges et al.27)				The prevalence in age 65 years and over was 28.2% (29.1% among men and 27.5% among women).		A total of 35.4% of all participants had multimorbidity.
Montes et al.28)	Strength and multimorbidity among community-dwelling elderly from southern Brazil	Participants who are ≥60 years and live in a medium-sized city	Two different definitions were used for dynapenia, which is the low muscle strength.	The overall dynapenia_E prevalence of the target population was 442 (33.2%) with 117 (23.7%) among men and 325 (38.8%) among women.	Multimorbidity was defined by self-report as the presence of at least five diseases diagnosed by a physician.	All participants had multimorbidity in 863 (64.6%) of the participants. In multimorbidity prevalence by sex, men accounted for 255 (51.7%) and women for 608 (72.1%).	The prevalence of multimorbidity was found to be 50% higher in men classified as dynapenia_Q than in men classified in the upper quartile (prevalence ratio, 1.50; 95% CI, 1.15–1.95), with the prevalence ratios increasing as grip strength decreased. Similarly, the prevalence of multimorbidity was higher in men with dynapenia_E (prevalence ratio, 1.32; 95% CI, 1.10–1.58).
			1) The first was maximum strength, <30 kg for men and 20 kg for women (dynapenia_E), according to the European Working Group on Sarcopenia.		For the evaluation of multimorbidity, participants were questioned about the presence of the following diseases and conditions: systemic arterial hypertension, myocardial infarction, diabetes, heart failure, emphysema, asthma, bronchitis, arthritis, Parkinson’s disease, renal failure, seizure disorders, hypercholesterolemia, stomach ulcers, osteoporosis, urinary incontinence, constipation, fecal incontinence, depression, glaucoma, deafness, difficulty in swallowing, insomnia, fainting, rhinitis, difficulty in speaking, stroke, mental disorders, and cancer.		The same was true for women, with a 16% higher prevalence of multimorbidity in women with dynapenia_Q (prevalence ratio, 1.16; 95% CI, 1.03–1.32).
			2) The second was defined as the lowest quartile for each sex (dynapenia_Q). In addition to muscle strength, low muscle mass (myopathy) was considered as a calf circumference of <34 cm for men and 33 cm for women using a 2-m non-stretch measure tape.				An increased prevalence of multimorbidity was also found in dynapenia_E(prevalence ratio, 1.09; 95% CI, 1.00–1.18).
Correa et al.29)	Association between dynapenic abdominal obesity and inflammatory profile in diabetic older community-dwelling patients with end-stage renal disease	Participants aged ≥60 years living in the community undergoing maintenance phase hemodialysis	Dynapenic was the lowest tertile (≤18 kg) for both men and women in handgrip strength.	The prevalence of dynapenic and dynapenic abdominal obesity was 25.9% and 19.8%, respectively.	All patients presented hypertension and diabetes.	-	Proportions of control, abdominal obesity, dynapenic, and dynapenic abdominal obesity were 38.5% 15.8%, 25.9%, and 19.8%, respectively.
Correa et al.29)					All patients presented hypertension and diabetes.	-	Dynapenic and dynapenic abdominal obesity groups displayed lower handgrip strength (ε2=0.711; p<0.0001) and handgrip-waist ratio (ε2=0.717; p<0.0001) when compared to control and obesity groups.
Veronese et al.30)	Dynapenic abdominal obesity and incident multimorbidity: findings from the English longitudinal study on ageing	Participants of ≥50 years living in England	Dynapenia was defined as handgrip strength of <27 kg in men and <16 kg in women.	The overall prevalence of dynapenia in all target population was 11.1%. The prevalence of dynapenia was 6.9% in target population without multimorbidity.	Multimorbidity was defined as having two or more chronic conditions. Information on the presence of medical conditions was collected by self-report based on doctor-diagnosed high blood pressure, diabetes, cancer, lung disease, heart conditions, stroke, psychiatric conditions, arthritis, asthma, high cholesterol levels, cataracts, Parkinson’s disease, hip fracture, Alzheimer’s disease, and other dementias. The total number of chronic conditions was then summed and multimorbidity was defined as ≥2 chronic conditions.	During the 10-year follow-up, 1,810 (55.0% of the initial population) developed multimorbidity and these people were significantly older, less educated, more frequent smokers, and less likely to consume alcohol than those without multimorbidity.	Dynapenia, abdominal obesity, and having dynapenic abdominal obesity were associated with a higher risk of multimorbidity during follow-up. In a comparison of participants without dynapenia and abdominal obesity, participants with dynapenia only did not report a significant risk of multimorbidity during follow-up (p=0.806). Compared to those without dynapenia or abdominal obesity, the presence of dynapenia only significantly increased the risk of diabetes (OR=2.44; 95% CI, 1.21–4.91; p=0.001).
Veronese et al.30)		Participants of ≥50 years living in England					In contrast, the presence of abdominal obesity (OR=1.505; 95% CI, 1.272–1.780; p<0.0001) and dynapenia abdominal obesity (OR=1.671; 95% CI, 1.201–2.325; p=0.002) significantly increased the risk of multimorbidity.