Women with low-energy fracture should be investigated for osteoporosis

Figures & data

Figure 1. Flow chart of inclusions and dropouts.

Table 1.  Basic characteristics of the total fracture (F) and reference (R) groups

Variable	Group ^a	N	Mean	SD	p ^b
Age	R	209	67.3	4.57
	F	303	67.5	5.60	0.7
Height (cm)	R	209	161	5.10
	F	303	162	6.00	<0.01
Weight (kg)	R	209	68.7	10.92
	F	303	68.7	12.73	1
BMI	R	209	26.6	4.11
	F	303	26.1	4.20	0.1
HAL	R	123	11.4	0.58
	F	299	11.5	0.75	0.1
Z-spine	R	198	–0.36	1.71
	F	299	–0.24	1.33	<0.01
Z-total hip	R	202	0.28	1.09
	F	300	–0.29	0.97	<0.01
Z-Arm	R	209	0.23	1.16
	F	294	–0.08	1.29	<0.01

^aF = fracture group; R reference group

^bSignificance between R and F groups

Table 2.  Diagnostic classification of fracture cases and non-fracture controls using two cut-off levels of the T-score

Diagnosis	Hip		Forearm		Fracture site Humerus		Vertebral		Any fracture		Non-fracture group
	n	%	n	%	n	%	n	%	n	%	n	%
Normal	2	5	18	11	4	11	1	2	25	8	122	58
Osteopenia	18	45	89	52	14	38	19	35	140	46	54	26
Osteoporosis
(T<-2.5) ^a	20	50	64	37	19	51	35	64	138	46	33	16
(T<-2.0) ^b	26	65	90	53	20	54	37	67	173	57	38	18
Total group	40	100	171	100	37	100	55	100	303	100	209	100

^aWHO Technical Report, 1994

^bSuggestion from The Medical Products Agency of Sweden

Table 3.  Hip- and vertebral fracture groups compared to the age-matched references

Variabel		Hip		P-value	Vertebral		P-value
		Fracture	Reference		Fracture	Reference
n		40	161	–	55	173	–
Age		69	69	1	69	69	0.8
Height		163	161	<0.05	161	161	1
Weight		65.8	69.1	0.1	68.0	69.3	0.5
BMI		24.8	25.8	0.2	26.2	26.3	0.9
HAL		11.7	11.4	<0.05	11.3	11.4	0.7
Z-Lumb. Spine		–0.22	0.70	<0.01	–0.55	0.54	<0.01
Z-Hip Total		–0.69	0.32	<0.01	–0.67	0.33	<0.01
Z-Arm (1/3)		–0.05	0.26	0.2	–0.45	0.26	<0.01
Current smokers %		15.0	13.0	0.8	14.5	14.3	1
Number of previous fractures ^a	0	52	100 ^b		40	100 ^b
	1	20	0		36	0
	2	18	0		13	0
	≥3	10	0		11	0

^aPercent in respective group with specified number of previous fractures

^bIn the reference group by definition there were no previous fracture

Patients having one or more vertebral fractures are only counted as having one previous fracture.

Table 4.  Forearm- and humerus fracture groups compared to the age-matched references

Variabel		Forearm		P-value	Humerus		P-value
		Fracture	Reference		Fracture	Reference
n		171	209	–	37	209	–
Age		67	66	0.6	67	67	0.9
Height		162	161	<0.01	162	161	0.4
Weight		69	69	0.6	70	69	0.6
BMI		26	26	0.5	27	26	0.4
HAL		11.5	11.4	<0.05	11.4	11.4	0.8
Z-lumb spine		–0.12	0.32	<0.01	–0.36	0.39	<0.01
Z-hip total		–0.10	0.28	<0.01	–0.19	0.29	<0.01
Z-arm (1/3)		0.02	0.21	0.1	–0.06	0.23	0.2
Current smokers %		13.0	13.0	1	8.1	11.0	0.6
Number of previous rractures ^a	0	54	100 ^b		54	100 ^b
	1	31	0		27	0
	2	10	0		16	0
	≥3	5	0		3	0

^aPercent in respective group with specified number of previous fractures

^bIn the reference group by definition there were no previous fracture

Patients having one or more vertebral fractures are only counted as having one previous fracture.

Table 5.  Odd ratio of osteopenia and osteoporosis in different fracture groups (95% confidence limits for OR)

Diagnosis/Fracture type	Hip			Forearm			Humerus			Vertebral			All fractures			No fracture
	n	%	OR	n	%	OR	n	%	OR	n	%	OR	n	%	OR	n	%
Normal
(T <–1)	2	5		18	11		4	11		1	2		25	8		122	58
Osteopenia
(T< –1 to –2.5)	18	45	20	89	58	11	14	38	7.9	19	35	43	140	46	13	54	26
Upper 95% CL			91			20			25			329			22
Lower 95% CL			4.6			6.1			2.5			5.6			7.4
Osteoporosis I ^a
(T <–2.0)	26	65	42	90	53	16	20	54	16	37	67	119	173	57	22	38	18
Upper 95% CL			184			30			50			895			39
Lower 95% CL			9.5			8.6			5.2			16			13
Osteoporosis II ^b
(T<–2.5)	20	50	37	64	37	13	19	51	18	35	64	129	138	46	20	33	16
Upper 95% CL			166			25			55			980			36
Lower 95% CL			8.2			6.9			5.6			17			12
Osteopenia +
Osteoporosis ^c	38	95	27	153	89	12	33	89	12	54	98	76	278	92	16	87	42
Upper 95% CL			113			21			34			558			26
Lower 95% CL			6.3			6.8			4.0			10			9.5
Total	40			171			37			55			303			209

^aAccording to suggestion for fractured subjects from The Medical Products Agency of Sweden

^bAccording to WHO Guidelines (WHO Technical report, 1994)

^c(T<–1)

Figure 2. Number of previous fractures in relation to Zscore of BMD at various sites. Error bars depict CI_low.

Figure 3. Bone mineral density (T-score, total hip) in reference and fracture groups, and in subgroups with risk factors. Mean and SD.