The Effect of Osteoporosis Medication on Risk Attenuation of Non-Trauma Fracture Among Adults with Cerebral Palsy: A Propensity Score-Matched Observational Study

Figures & data

Table 1 Baseline Descriptive Characteristics of Propensity-Matched Participants (1:6) by Status of Cerebral Palsy (CP) and Prescribed Osteoporosis Medication (Meds)

	CPMeds+ (n=306)	CPMeds- (n=1836)	Non-CPMeds+ (n=1836)
	% (n)	% (n)	% (n)
Age, mean (SD)	61.6 (14.9)	61.5 (16.2)	71.6 (10.7)
18–40 years	9.5 (29)	10.7 (196)	0.9 (16)
41–64 years	45.4 (139)	41.8 (767)	22.8 (418)
≥65 years	45.1 (138)	47.6 (873)	76.4 (1402)
Sex
Women	75.8 (232)	76.3 (1401)	75.4 (1384)
Men	24.2 (74)	23.7 (435)	24.6 (452)
Race
White	70.3 (215)	69.4 (1274)	72.3 (1327)
Black	8.8 (27)	9.2 (169)	7.5 (138)
Hispanic	5.2 (16)	7.1 (131)	7.9 (145)
Asian	4.3 (13)	2.3 (42)	3.6 (66)
Unknown/missing	11.4 (35)	12.0 (220)	8.7 (160)
US region
West	28.1 (86)	28.4 (522)	28.0 (514)
Midwest	21.2 (65)	22.9 (421)	19.8 (364)
South	37.3 (114)	32.7 (600)	38.7 (711)
Northeast	13.4 (41)	16.0 (293)	13.5 (247)
Insurance type
Commercial	23.5 (72)	23.7 (435)	22.6 (415)
Medicare Advantage	76.5 (234)	76.3 (1401)	77.4 (1421)
Comorbid neurodevelopmental disabilities	40.2 (123)	38.3 (703)	5.7 (105)
Elixhauser comorbidity index
Mean (SD)	2.4 (2.1)	2.4 (2.4)	2.5 (2.2)
Median (IQR)	2.0 (1.0–4.0)	2.0 (1.0–4.0)	2.0 (1.0–4.0)
Osteoporosis medication
New med users	34.3 (105)	0 (0)	35.0 (642)
Consistent med users	65.7 (201)	0 (0)	65.0 (1194)
Glucocorticoid medications	16.0 (49)	15.5 (285)	14.6 (268)
Anti-epileptic medications	32.7 (100)	31.6 (580)	32.0 (588)

Abbreviations: SD, standard deviation; IQR, interquartile range.

Table 2 Prevalence and Unadjusted Risk Ratio (RR) of Pre- and Post-Index Non-Trauma Fracture (NTFx) Among Propensity-Matched Participants (1:6) by Status of Cerebral Palsy (CP) and Prescribed Osteoporosis Medication (Meds)

	CPMeds+ (n=306)	CPMeds- (n=1836)	Non-CPMeds+ (n=1836)
Pre-index period	% (n)	% (n)	% (n)
Any NTFx	12.1 (37)	4.1 (76)	12.0 (221)
Vertebral column or hip	7.8 (24)	2.5 (45)	9.53 (175)
Lower extremities	4.6 (14)	1.3 (23)	2.6 (47)
Upper extremities	2.3 (7)	0.6 (11)	1.1 (21)
Post-index period	% (n)	% (n)	% (n)
Any NTFx	12.8 (39)	6.8 (124)	10.6 (195)
Vertebral column or hip	4.3 (13)	3.7 (67)	6.8 (125)
Lower extremities	4.6 (14)	1.6 (30)	1.4 (25)
Upper extremities	3.3 (10)	1.5 (28)	1.9 (35)
RR (pre- to post-index)	RR (95% CI)	RR (95% CI)	RR (95% CI)
Any NTFx	1.05 (0.69, 1.61)	1.63 (1.24, 2.16)	0.88 (0.74, 1.06)
Vertebral column or hip	0.54 (0.28, 1.04)	1.49 (1.03, 2.16)	0.71 (0.57, 0.89)
Lower extremities	1.00 (0.49, 2.06)	1.30 (0.76, 2.24)	0.53 (0.33, 0.86)
Upper extremities	1.43 (0.55, 3.70)	2.55 (1.27, 5.10)	1.67 (0.97, 2.85)

Abbreviation: CI, confidence interval.

Table 3 Odds Ratio (OR) of Non-Trauma Fracture (NTFx) Among Propensity-Matched Participants (1:6) by Status of Cerebral Palsy (CP) and Prescribed Osteoporosis Medication (Meds)

	Unadjusted OR (CPMeds+ vs CPMeds-)	Unadjusted OR (CPMeds+ vs Non-CPMeds+)	Adjusted* OR (CPMeds+ vs CPMeds-)	Adjusted** OR (CPMeds+ vs Non-CPMeds+)
Pre-index period	OR (95% CI)	OR (95% CI)	OR (95% CI)	OR (95% CI)
Any NTFx	3.19 (2.11, 4.82)	1.01 (0.69, 1.46)		1.01 (0.68, 1.51)
NTFx of vertebral column or hip	3.39 (2.03, 5.65)	0.81 (0.52, 1.26)		0.93 (0.58, 1.49)
NTFx of lower extremities	3.78 (1.92, 7.43)	1.83 (0.99, 3.36)		1.27 (0.65, 2.50)
NTFx of the upper extremities	3.88 (1.49, 10.10)	2.02 (0.85, 4.80)		***
Post-index period
Any NTFx	2.02 (1.38, 2.96)	1.23 (0.85, 1.78)	1.78 (1.20, 2.64)	1.43 (0.97, 2.13)
NTFx of vertebral column or hip	1.17 (0.64, 2.15)	0.61 (0.34, 1.09)	1.00 (0.54, 1.87)	0.82 (0.45, 1.52)
NTFx of lower extremities	2.89 (1.51, 5.51)	3.47 (1.79, 6.76)	2.56 (1.33, 4.94)	2.86 (1.39, 5.88)
NTFx of the upper extremities	2.18 (1.05, 4.54)	1.74 (0.85, 3.55)	***	***

Notes: *Adjusted for pre-index NTFx corresponding to the same site (eg, pre-index NTFx of the lower extremities when post-index NTFx of lower extremities was the outcome). **For the pre-index period, the model was adjusted for age and comorbid neurodevelopmental disabilities. For the post-index period, the model was adjusted for age, comorbid neurodevelopmental disabilities, and pre-index NTFx corresponding to the same site. ***Too few outcome cases for adjusted analysis.

Abbreviation: CI, confidence interval.

Figure 1 Unadjusted prevalence of pre- and post-index non-trauma fracture (NTFx) as (A) any NTFx, (B) NTFx of the vertebral column or hip, (C) NTFx of the lower extremities, and (D) NTFx of the upper extremities for propensity-matched adults (1:6) by status of cerebral palsy (CP) as with CP (CP) or without CP (w/o CP), and prescribed osteoporosis medication (Meds).

Table 4 The Ratio of the Risk Ratio (RRR) of Pre- to Post-Index Non-Trauma Fracture (NTFx) Among Participants by Status of Cerebral Palsy (CP), Prescribed Osteoporosis Medication (Meds), and Whether the Medication Group Was a New or Consistent User

	Any NTFx	NTFx of the Vertebral Column or Hip	NTFx of the Lower Extremities
Propensity score matched groups	RRR (95% CI)	RRR (95% CI)	RRR (95% CI)
CPMeds+ vs CPMeds-	0.65 (0.41, 1.04)	0.36 (0.18, 0.74)	0.77 (0.33, 1.77)
CPMeds+ vs non-CPMeds+*	1.19 (0.78, 1.83)	0.76 (0.40, 1.45)	1.89 (0.84, 4.24)
New med and consistent med users
New users with CP vs CPMeds-**	0.39 (0.22, 0.71)	0.25 (0.10, 0.66)	0.39 (0.13, 1.11)
Consistent users with CP vs CPMeds-	1.17 (0.59, 2.34)	0.59 (0.23, 1.50)	1.73 (0.52, 5.76)
New vs consistent users with CP**	0.33 (0.15, 0.76)	0.43 (0.12, 1.49)	0.22 (0.05, 0.93)
New users with vs without CP	0.81 (0.45, 1.43)	0.62 (0.24, 1.58)	0.80 (0.26, 2.44)
Consistent users with vs without CP	1.94 (0.98, 3.81)	1.03 (0.41, 2.58)	5.19 (1.42, 18.85)

Notes: *Adjusted for age and comorbid neurodevelopmental disabilities. **Adjusted for glucocorticoid medication for any NTFx.

Abbreviation: CI, confidence interval.

Figure 2 Unadjusted prevalence of pre- and post-index any non-trauma fracture (NTFx) for participants by status of cerebral palsy (CP) as with CP (CP) or without CP (w/o CP), prescribed osteoporosis medication (Meds), and whether the medication group was a new med or consistent med user.

Table 5 Prevalence and Unadjusted Risk Ratio (RR) of Pre- and Post-Index Non-Trauma Fracture (NTFx) Among Participants by Status of Cerebral Palsy (CP) and Whether the Osteoporosis Medication Group Was a New or Consistent User

	New Users with CP (n=105)	Consistent Users with CP (n=201)	New Users without CP (n=642)	Consistent Users without CP (n=1194)
Pre-index period	% (n)	% (n)	% (n)
Any NTFx	23.8 (25)	6.0 (12)	19.0 (122)	8.3 (99)
Vertebral column or hip	15.2 (16)	4.0 (8)	15.0 (96)	6.6 (79)
Lower extremities	9.5 (10)	2.0 (4)	3.7 (24)	1.9 (23)
Post-index period	% (n)	% (n)	% (n)
Any NTFx	15.2 (16)	11.4 (23)	15.1 (97)	8.2 (98)
Vertebral column or hip	5.7 (6)	3.5 (7)	9.0 (53)	5.6 (67)
Lower extremities	4.8 (5)	4.5 (9)	2.3 (15)	0.8 (10)
RR (pre- to post-index)	RR (95% CI)	RR (95% CI)	RR (95% CI)
Any NTFx	0.64 (0.36, 1.13)	1.92 (0.98, 3.75)	0.80 (0.62, 1.01)	0.99 (0.76, 1.29)
Vertebral column or hip	0.38 (0.15, 0.92)	0.88 (0.32, 2.37)	0.60 (0.44, 0.82)	0.86 (0.63, 1.17)
Lower extremities	0.50 (0.18, 1.41)	2.25 (0.70, 7.19)	0.63 (0.33, 1.18)	0.44 (0.21, 0.91)

Abbreviation: CI, confidence interval.