Low metacarpal index predicts hip fracture: A prospective population study of 3,561 subjects with 15 years of follow-up

Figures & data

Table 1.  Metacarpal index (MCI) by age, sex, body mass index, body height, educational level, smoking status, alcohol intake, physical activity at leisure, and selfrated general health, adjusted independently of each other (n=3,561)

Determinant	n	Adjusted mean of MCI	SD^a	P-value^b
Age (years)
30–44	979	0.63	0.09
45–54	831	0.61	0.09
55–64	817	0.55	0.09	<0.001
65–74	650	0.50	0.09
>75	284	0.45	0.09
Sex
Male	1,547	0.57	0.09	0.9
Female	2,014	0.57	0.12
Body mass index
(kg/m^2)
<20	136	0.57	0.13
20–24.9	1,305	0.56	0.11
25–29.9	1,468	0.57	0.10	<0.001
30–34.9	540	0.59	0.11
≥35.0	112	0.57	0.09
Body height (cm)
<160	1,672	0.57	0.11
160–180	1,593	0.57	0.10	0.01
>180	296	0.56	0.09
Educational level (yr)
<8	2,623	0.57	0.10
8–12	653	0.57	0.10	0.9
>12	285	0.57	0.10
Smoking status
Never smoked	2,013	0.57	0.11
Ex-smoker	782	0.57	0.09
Pipe, cigars or	484	0.56	0.10	0.001
<20 cigarettes/day
>20 cigarettes/day	282	0.56	0.10
Alcohol intake
(grams of ethanol/week)
0	1,799	0.57	0.11
1–49	1,399	0.57	0.10
50–249	122	0.57	0.09	0.3
≥249	241	0.56	0.09
Physical activity at leisure
low	1,426	0.57	0.11
moderate	1,686	0.57	0.10	0.3
high	449	0.57	0.10
Self-rated general health
good	258	0.56	0.09
fairly good	924	0.57	0.11
moderate	1,591	0.57	0.10	0.7
rather poor	648	0.57	0.11
poor	140	0.58	0.10

n=number of subjects.

^a SD=unadjusted standard deviation.

^b P-value for heterogeneity of the adjusted means of metacarpal index.

Table 2.  Adjusted relative risk (RR) and its 95% confidence interval (CI) of hip fracture by metacarpal index, age, sex, body mass index, height, level of education, smoking, alcohol intake, physical activity at leisure and self reported general health, adjusted independently of each other (n=3,561)

	Number of subjects with hip fracture	Numbers of subjects examined	RR	95% CI
MCI decile: ≥0.70	1	357	1.0
<0.70	3	365	1.9	0.2–19
<0.66	2	356	1.3	0.1–14
<0.63	7	349	2.5	0.3–21
<0.60	7	357	3.1	0.4–26
<0.57	11	357	4.1	0.5–32
<0.54	10	359	3.4	0.4–28
<0.52	14	355	3.7	0.5–29
<0.49	21	358	3.9	0.5–31
<0.44	42	356	6.3	0.8–49
Age (years): 30–44	1	979	1.0
45–54	6	831	6.9	0.8–59
55–64	27	817	28.2	3.6–220
65–74	51	650	79.8	10–631
>75	32	284	158.9	19–1311
Sex: male	28	1,547	1.0
female	89	2,014	2.0	1.1–3.7
Body mass index (kg/m^2)
≤20.0	6	136	1.4	0.6–3.5
20.0–24.9	37	1,305	1.0
25.0–29.9	48	1,496	0.9	0.6–1.4
30.0–34.9	23	540	0.9	0.5–1.6
≥35.0	3	112	0.6	0.2–2.1
Height a: short	75	1,672	1.0
average	37	1,593	1.2	0.8–1.7
tall	5	296	2.7	1.0–7.4
Level of education
<8 years	98	2,623	1.0
8–12 years	14	653	1.0	0.6–1.8
>12 years	5	285	1.4	0.5–3.7
Smoking status
Never smoked	81	2,013	1.0
Ex-smoker	20	782	1.5	0.8–2.8
Pipe, cigars or
<20 cigarettes/day	11	484	1.3	0.6–2.7
≥20 cigarettes/day	5	282	1.6	0.6–4.8
Alcohol intake
(grams of ethanol/week)
0	88	1,799	1.0
1–49	21	1,399	0.7	0.4–1.3
50–249	3	122	2.2	0.6–7.8
≥249	5	241	2.1	0.7–5.8
Physical activity at leisure
low	73	1,426	1.0
moderate	35	1,686	0.7	0.5–1.1
high	9	449	1.1	0.5–2.2
Self–rated general health
good	2	258	1.0
fairly good	14	924	1.3	0.3–5.9
middling	49	1,591	2.0	0.5–8.3
rather poor	36	648	3.3	0.8–14
poor	16	140	6.8	1.5–31

^a The criteria of shortness for men and women were < 170 and < 160 cm, respectively; and for tallness, ≥ 180 and ≥ 170 cm, respectively.

Table 3.  Relative risk of hip fracture and its 95% confidence interval (CI) per decrement of metacarpal index by 1 standard deviation (0.1)

Model	Relative risk	95% CI	P-value for trend
Unadjusted	2.8	2.4–3.3	<0.001
Adjusted for age and sex	1.5	1.2–1.9	<0.001
	1.5	1.2–1.8	0.001

^a Adjusted for age, sex, body mass index, height, level of education, smoking, alcohol intake, physical activity at leisure and self-reported general health.