J Clin Med Res

Journal of Clinical Medicine Research, ISSN 1918-3003 print, 1918-3011 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Med Res and Elmer Press Inc

Journal website https://jocmr.elmerjournals.com

Original Article

Volume 18, Number 11, November 2026, pages 850-858

Usefulness of Phase Angle as an Overall Marker of Muscle Health in Older Patients With Type 2 Diabetes

↓ Figure 1. Annual rate of changes in muscle mass and strength. Data are expressed as mean ± SE. *P < 0.05, **P < 0.01, ***P < 0.001 vs. SMI. ^###P < 0.001 vs. ipsilateral handgrip strength. SMI: skeletal muscle index; Rt- and Lt-HG: right and left handgrip strength, respectively; Rt- and Lt-Leg Ex: right and left leg extension strength, respectively.

↓ **Table 1.** Clinical Characteristics of the Patients at Baseline and 3 Years
	Baseline	3 years	P
N = 101 (male 61, female 40). Data are expressed as mean ± SD. SD: standard deviation; BMI: body mass index; HbA1c: glycated hemoglobin; eGFR: estimated glomerular filtration rate; DPP-4: dipeptidyl peptidase-4; SGLT-2: sodium-glucose cotransporter-2; α-GI: α-glucosidase inhibitor; GLP-1: glucagon-like peptide-1; GIP: glucose-dependent insulinotropic polypeptide
Variables
Age, years	69.77 ± 8.231	72.91 ± 8.271	< 0.0001
BMI, kg/m²	25.32 ± 4.136	24.90 ± 4.090	< 0.0001
HbA1c, %	7.468 ± 0.9375	7.366 ± 1.064	0.2733
eGFR, mL/min/1.73 m²	62.68 ± 14.90	61.28 ± 15.18	0.2271
Serum albumin, g/dL	4.255 ± 0.2622	4.333 ± 0.3293	0.1607
Medication of anti-diabetic agent usage
No medication, n (%)	17 (16.9)	15 (14.9)
Metformin, n (%)	36 (35.6)	39 (38.6)
DPP-4 inhibitor, n (%)	68 (67.3)	63 (62.4)
SGLT-2 inhibitor, n (%)	17 (16.8)	28 (27.7)
Glinide, n (%)	21 (20.8)	7 (6.9)
α-GI, n (%)	8 (7.9)	10 (9.9)
Sulfonylurea, n (%)	28 (27.7)	28 (27.7)
GLP-1 receptor agonist (oral), n (%)	3 (3.9)	8 (7.9)
GLP-1 receptor agonist (injection), n (%)	6 (5.9)	2 (2.0)
GIP/GLP-1 receptor agonist, n (%)	0 (0.0)	3 (3.0)
Insulin, n (%)	10 (9.9)	5 (5.0)

↓ Table 1. Clinical Characteristics of the Patients at Baseline and 3 Years

Baseline

3 years

N = 101 (male 61, female 40). Data are expressed as mean ± SD. SD: standard deviation; BMI: body mass index; HbA1c: glycated hemoglobin; eGFR: estimated glomerular filtration rate; DPP-4: dipeptidyl peptidase-4; SGLT-2: sodium-glucose cotransporter-2; α-GI: α-glucosidase inhibitor; GLP-1: glucagon-like peptide-1; GIP: glucose-dependent insulinotropic polypeptide

Variables

Age, years

69.77 ± 8.231

72.91 ± 8.271

< 0.0001

BMI, kg/m²

25.32 ± 4.136

24.90 ± 4.090

< 0.0001

HbA1c, %

7.468 ± 0.9375

7.366 ± 1.064

0.2733

eGFR, mL/min/1.73 m²

62.68 ± 14.90

61.28 ± 15.18

0.2271

Serum albumin, g/dL

4.255 ± 0.2622

4.333 ± 0.3293

0.1607

Medication of anti-diabetic agent usage

No medication, n (%)

17 (16.9)

15 (14.9)

Metformin, n (%)

36 (35.6)

39 (38.6)

DPP-4 inhibitor, n (%)

68 (67.3)

63 (62.4)

SGLT-2 inhibitor, n (%)

17 (16.8)

28 (27.7)

Glinide, n (%)

21 (20.8)

7 (6.9)

α-GI, n (%)

8 (7.9)

10 (9.9)

Sulfonylurea, n (%)

28 (27.7)

GLP-1 receptor agonist (oral), n (%)

3 (3.9)

8 (7.9)

GLP-1 receptor agonist (injection), n (%)

6 (5.9)

2 (2.0)

GIP/GLP-1 receptor agonist, n (%)

0 (0.0)

3 (3.0)

Insulin, n (%)

10 (9.9)

5 (5.0)

↓ **Table 2.** Body Composition, Phase Angle, and Muscle Strength of the Participants at Baseline and 3 Years
Variables	Baseline	3 years	P
N = 101 (male 61, female 40). Data are expressed as mean ± SD. ECW: extracellular water; FI: fat index; PhA: phase angle; SD: standard deviation; SMI: skeletal muscle index; SPPB: Short Physical Performance Battery; TBW: total body water.
FI, kg/m²	7.857 ± 3.642	7.866 ± 3.781	0.9517
SMI, kg/m²	7.640 ± 0.8772	7.488 ± 0.9041	< 0.0001
ECW/TBW	0.4404 ± 0.0149	0.4499 ± 0.0950	0.3185
Right PhA	5.331 ± 0.6941	5.044 ± 0.5744	< 0.0001
Left PhA	5.273 ± 0.7370	4.961 ± 0.6395	< 0.0001
Right handgrip strength, kg	32.50 ± 8.632	30.96 ± 8.457	0.0003
Left handgrip strength, kg	30.18 ± 7.816	28.76 ± 8.258	< 0.0001
Right leg extension strength, kg	31.90 ± 11.54	28.06 ± 12.34	< 0.0001
Left leg extension strength, kg	31.04 ± 12.29	27.03 ± 12.21	< 0.0001
SPPB	11.80 ± 0.5318	11.66 ± 0.8317	0.1010

↓ Table 2. Body Composition, Phase Angle, and Muscle Strength of the Participants at Baseline and 3 Years

Variables

Baseline

3 years

N = 101 (male 61, female 40). Data are expressed as mean ± SD. ECW: extracellular water; FI: fat index; PhA: phase angle; SD: standard deviation; SMI: skeletal muscle index; SPPB: Short Physical Performance Battery; TBW: total body water.

FI, kg/m²

7.857 ± 3.642

7.866 ± 3.781

0.9517

SMI, kg/m²

7.640 ± 0.8772

7.488 ± 0.9041

< 0.0001

ECW/TBW

0.4404 ± 0.0149

0.4499 ± 0.0950

0.3185

Right PhA

5.331 ± 0.6941

5.044 ± 0.5744

< 0.0001

Left PhA

5.273 ± 0.7370

4.961 ± 0.6395

< 0.0001

Right handgrip strength, kg

32.50 ± 8.632

30.96 ± 8.457

0.0003

Left handgrip strength, kg

30.18 ± 7.816

28.76 ± 8.258

< 0.0001

Right leg extension strength, kg

31.90 ± 11.54

28.06 ± 12.34

< 0.0001

Left leg extension strength, kg

31.04 ± 12.29

27.03 ± 12.21

< 0.0001

SPPB

11.80 ± 0.5318

11.66 ± 0.8317

0.1010

↓ **Table 3.** Simple Correlation Analysis at Baseline
	Correlation coefficient with right PhA	P	Correlation coefficient with left PhA	P
ECW: extracellular water; eGFR: estimated glomerular filtration rate; FI: fat index; HbA1c: glycated hemoglobin; PhA: phase angle; SMI: skeletal muscle index; SPPB: Short Physical Performance Battery; TBW: total body water.
Age, years	−0.4027	< 0.0001	−0.3776	< 0.0001
Sex, female 1/male 2	0.3936	< 0.0001	0.3487	0.0003
HbA1c, %	0.0639	0.5264	0.0493	0.6254
eGFR, mL/min/1.73 m²	0.0692	0.4924	0.0381	0.7058
Serum albumin, g/dL	−0.0013	0.9915	0.2215	0.0762
FI, kg/m²	−0.2001	0.0439	−0.1124	0.2632
SMI, kg/m²	0.6813	< 0.0001	0.6927	< 0.0001
ECW/TBW	−0.3665	0.0002	−0.3352	0.0006
Right handgrip strength, kg	0.5633	< 0.0001	-	-
Left handgrip strength, kg	-	-	0.4419	< 0.001
Right leg extension strength, kg	0.5034	< 0.0001	-	-
Left leg extension strength, kg	-	-	0.3963	0.0002
SPPB	0.1589	0.1142	0.1609	0.1099

↓ Table 3. Simple Correlation Analysis at Baseline

Correlation coefficient with right PhA

Correlation coefficient with left PhA

ECW: extracellular water; eGFR: estimated glomerular filtration rate; FI: fat index; HbA1c: glycated hemoglobin; PhA: phase angle; SMI: skeletal muscle index; SPPB: Short Physical Performance Battery; TBW: total body water.

Age, years

−0.4027

< 0.0001

−0.3776

< 0.0001

Sex, female 1/male 2

0.3936

< 0.0001

0.3487

0.0003

HbA1c, %

0.0639

0.5264

0.0493

0.6254

eGFR, mL/min/1.73 m²

0.0692

0.4924

0.0381

0.7058

Serum albumin, g/dL

−0.0013

0.9915

0.2215

0.0762

FI, kg/m²

−0.2001

0.0439

−0.1124

0.2632

SMI, kg/m²

0.6813

< 0.0001

0.6927

< 0.0001

ECW/TBW

−0.3665

0.0002

−0.3352

0.0006

Right handgrip strength, kg

0.5633

< 0.0001

Left handgrip strength, kg

0.4419

< 0.001

Right leg extension strength, kg

0.5034

< 0.0001

Left leg extension strength, kg

0.3963

0.0002

SPPB

0.1589

0.1142

0.1609

0.1099

↓ **Table 4.** Simple Correlation Analysis at 3 Years
	Correlation coefficient with right PhA	P	Correlation coefficient with left PhA	P
ECW: extracellular water; eGFR: estimated glomerular filtration rate; FI: fat index; HbA1c: glycated hemoglobin; PhA: phase angle; SMI: skeletal muscle index; SPPB: Short Physical Performance Battery; TBW: total body water.
Age, years	−0.4292	< 0.0001	−0.3674	0.0001
Sex, female 1/male 2	0.2211	0.0268	0.2403	0.0152
HbA1c, %	0.0168	0.8677	0.0435	0.6665
eGFR, mL/min/1.73 m²	0.1209	0.2292	0.1112	0.2269
Serum albumin, g/dL	−0.0435	0.6657	−0.0269	0.7896
FI, kg/m²	−0.1485	0.4821	−0.1289	0.1987
SMI, kg/m²	0.5949	< 0.0001	0.6207	< 0.0001
ECW/TBW	−0.0286	0.7764	−0.0506	0.6153
Right handgrip strength, kg	0.4929	0.0005	-	-
Left handgrip strength, kg	-	-	0.4277	< 0.0001
Right leg extension strength, kg	0.4755	<0.0001	-	-
Left leg extension strength, kg	-	-	0.4134	< 0.0001
SPPB	0.2286	0.0215	0.2175	0.0289

↓ Table 4. Simple Correlation Analysis at 3 Years

Correlation coefficient with right PhA

Correlation coefficient with left PhA

Age, years

−0.4292

< 0.0001

−0.3674

0.0001

Sex, female 1/male 2

0.2211

0.0268

0.2403

0.0152

HbA1c, %

0.0168

0.8677

0.0435

0.6665

eGFR, mL/min/1.73 m²

0.1209

0.2292

0.1112

0.2269

Serum albumin, g/dL

−0.0435

0.6657

−0.0269

0.7896

FI, kg/m²

−0.1485

0.4821

−0.1289

0.1987

SMI, kg/m²

0.5949

< 0.0001

0.6207

< 0.0001

ECW/TBW

−0.0286

0.7764

−0.0506

0.6153

Right handgrip strength, kg

0.4929

0.0005

Left handgrip strength, kg

0.4277

< 0.0001

Right leg extension strength, kg

0.4755

<0.0001

Left leg extension strength, kg

0.4134

< 0.0001

SPPB

0.2286

0.0215

0.2175

0.0289

↓ **Table 5.** Association of Change in Each Variable of Body Composition and Muscle Strength With Change in Phase Angle From Baseline to 3 Years
	Coefficient of linkage (λ) with right PhA	P	Coefficient of linkage (λ) with left PhA	P
ECW: extracellular water; FI: fat index; PhA: phase angle; SMI: skeletal muscle index; SPPB: Short Physical Performance Battery; TBW: total body water.
FI, kg/m²	−0.0704	0.4822	−0.1290	0.1987
SMI, kg/m²	0.5866	< 0.0001	0.6525	< 0.0001
ECW/TBW	0.0042	0.9665	0.0069	0.9448
Right handgrip strength, kg	0.5346	0.0005	-	-
Left handgrip strength, kg	-	-	0.2498	0.0176
Right leg extension strength, kg	0.2569	0.0145	-	-
Left leg extension strength, kg	-	-	0.3449	0.0011
SPPB	0.2884	0.0035	0.2619	0.0082

↓ Table 5. Association of Change in Each Variable of Body Composition and Muscle Strength With Change in Phase Angle From Baseline to 3 Years

Coefficient of linkage (λ) with right PhA

Coefficient of linkage (λ) with left PhA

ECW: extracellular water; FI: fat index; PhA: phase angle; SMI: skeletal muscle index; SPPB: Short Physical Performance Battery; TBW: total body water.

FI, kg/m²

−0.0704

0.4822

−0.1290

0.1987

SMI, kg/m²

0.5866

< 0.0001

0.6525

< 0.0001

ECW/TBW

0.0042

0.9665

0.0069

0.9448

Right handgrip strength, kg

0.5346

0.0005

Left handgrip strength, kg

0.2498

0.0176

Right leg extension strength, kg

0.2569

0.0145

Left leg extension strength, kg

0.3449

0.0011

SPPB

0.2884

0.0035

0.2619

0.0082