The Inverse Association of Leg Fat Mass and Osteoporosis in Individuals with Type 2 Diabetes Independent of Lean Mass

Figures & data

Table 1 Characteristics of Study Participants

	Total	Female	Male	P-value
N	1,259	536	723
Age (years)	59 (55–64)	60 (55–64)	58 (54–63)	<0.001
Diabetes duration (months)	123.00 (53.0–185.0)	124.5 (62.0–188.0)	116.0 (45.8–174.5)	0.014
BMI (kg/m^2)	24.47±3.27	24.64±3.60	24.34±2.99	0.109
WC (cm)	89 (83–95)	88.00 (82.00–94.00)	89.00 (84.00–95.00)	0.030
HbA1c (%)	9.4 (7.9–11.2)	9.5 (7.9–11.2)	9.4 (7.9–11.2)	0.885
HOMA-IR	2.18 (1.30–3.68)	2.38 (1.52–4.09)	2.00 (1.17–3.36)	<0.001
TG (mmol/L)	1.45 (1.04–2.18)	1.53 (1.10–2.22)	1.39 (0.99–2.14)	0.010
TC (mmol/L)	4.55 (3.80–5.51)	4.90 (3.92–5.77)	4.40 (3.76–5.22)	<0.001
HDL-c (mmol/L)	1.00 (0.85–1.20)	1.04 (0.89–1.25)	0.96 (0.82–1.14)	<0.001
LDL-c (mmol/L)	2.44 (1.91–3.16)	2.56 (1.93–3.32)	2.38 (1.90–3.02)	0.002
Arm LM (kg)	5.47 (4.49–6.37)	5.09 (4.17–6.08)	5.80 (4.81–6.55)	<0.001
Leg LM (kg)	13.93 (12.24–15.48)	13.43 (11.56–15.08)	14.31 (12.78–15.75)	<0.001
Truncal LM (kg)	22.50 (19.40–25.10)	21.10 (18.40–24.30)	23.50 (20.50–25.70)	<0.001
Arm FM (kg)	1.90 (1.40–2.70)	2.00 (1.38–2.90)	1.90 (1.40–2.58)	0.037
Leg FM (kg)	4.60 (3.70–5.60)	4.60 (3.60–5.80)	4.60 (3.80–5.60)	0.405
Truncal FM (kg)	8.70 (6.40–11.10)	8.80 (6.40–11.70)	8.60 (6.40–10.80)	0.075
Total FLR	0.36 (0.26–0.48)	0.39 (0.29–0.53)	0.35 (0.27–0.45)	<0.001
Total LM	42.12 (35.87–47.62)	39.18 (33.69–45.54)	44.24 (38.25–48.76)	<0.001
Lumbar spine BMD	1.100 (0.963–1.225)	1.058 (0.929–1.199)	1.125 (0.992–1.237)	<0.001
Femoral neck BMD	0.902 (0.796–1.003)	0.882 (0.778–0.981)	0.941 (0.818–1.020)	<0.001
Total hip BMD	0.956 (0.859–1.061)	0.941 (0.833–1.045)	0.970 (0.873–1.072)	0.001
Current smoker (yes, %)	296 (23.51)	6 (1.12)	289 (22.95)	<0.001
Current drinker (yes, %)	445 (35.35)	22 (4.10)	423 (39.97)	<0.001
Fish intake (yes, %)	715 (56.79)	280 (52.24)	435 (60.17)	0.006

Notes: Data are the mean±standard deviation, median (interquartile range), and n (%). The t-test and Chi-squared test were used to compare female and male groups.

Abbreviations: BMI, body mass index; WC, waist circumference; HbA1c, glycated hemoglobin A1c; HOMA-IR, homeostasis model assessment-insulin resistance; TG, triglyceride; TC, total cholesterol; HDL-c, high-density lipoprotein cholesterol; LDL-c, low-density lipoprotein cholesterol; LM, lean mass; FM, fat mass; total FLR, total fat mass/lean mass ratio.

Table 2 Univariate and Multivariate Analyses for Associations Between Body Composition and BMD Value at Various Skeletal Sites for Females and Males

Variable	Lumbar Spine BMD						Femoral Neck BMD						Total Hip BMD
	Univariate Model^a			Multivariate Model^b			Univariate Model^a			Multivariate Model^b			Univariate Model ^a			Multivariate Model^b
	ß	SE	P-value	ß	SE	P-value	ß	SE	P-value	ß	SE	P-value	ß	SE	P-value	ß	SE	P-value
Female
Arm FM	0.011	0.006	0.084	−0.044	0.024	0.065	0.008	0.005	0.122	−0.004	0.020	0.834	0.015	0.005	0.005	−0.028	0.020	0.152
Leg FM	0.015	0.005	0.003	0.010	0.005	0.045	0.010	0.004	0.013	0.008	0.004	0.037	0.017	0.004	<0.001	0.016	0.004	<0.001
Trunk FM	0.008	0.002	<0.001	0.003	0.006	0.611	0.006	0.002	0.001	0.001	0.005	0.909	0.008	0.002	<0.001	0.005	0.005	0.342
Total LM	0.012	0.001	<0.001	0.012	0.001	<0.001	0.010	0.001	<0.001	0.010	0.001	<0.001	0.010	0.001	<0.001	0.010	0.001	<0.001
Male
Arm FM	−0.466	1.920	0.809	0.469	8.864	0.958	0.010	0.005	0.060	0.001	0.019	0.978	0.013	0.006	0.020	−0.020	0.021	0.331
Leg FM	−0.455	1.342	0.735	−0.062	4.581	0.602	0.015	0.004	<0.001	0.013	0.004	0.001	0.018	0.004	<0.001	0.015	0.004	<0.001
Trunk FM	0.071	0.571	0.902	0.699	1.887	0.711	0.007	0.002	<0.001	−0.003	0.004	0.513	0.008	0.002	<0.001	0.003	0.005	0.549
Total LM	0.152	0.274	0.580	0.161	0.441	0.715	0.009	0.001	<0.001	0.008	0.001	<0.001	0.008	0.001	<0.001	0.008	0.001	<0.001

Notes: ^aP-values were generated using a simple regression analysis. ^bP-values were generated using a multiple linear regression analysis after adjusting for age, diabetes duration, glucose, and lipid metabolism indexes (HbA1c, HOMA-IR, TG, HDL-c, LDL-c), and lifestyle (smoking, alcohol, fish intake).

Abbreviation: ß, regression coefficient.

Figure 1 Comparison of leg fat mass between normal bone mineral density, osteopenia, and osteoporosis in different waist circumference groups. (A) Comparison of leg fat mass in females; (B) comparison of leg fat mass in males. *P<0.05 versus normal bone mineral density, **P<0.001 versus normal bone mineral density.

Figure 2 Adjusted odds ratio of osteoporosis according to tertiles of leg fat mass. The odds ratio with corresponding 95% confidence interval were adjusted for age, lifestyles (intake of fish, smoking, alcohol), glucose and lipid metabolism indexes (HbA1c, HOMA-IR, TG, HDL-c, LDL-c), diabetes duration, and total lean mass. T1 is the reference group.