Table 3.

Hazard Ratios from Cox Regression Models with Time Since Loss of Ambulation, Muscular Dystrophy Surveillance, Tracking, and Research Network, 1982-2011

Variable	Unadjusted Hazard Ratio (95% Confidence Interval)	Adjusted a Hazard Ratio (95% Confidence Interval)
Race/Ethnicity
White, Non-Hispanic	Referent	Referent
Black, Non-Hispanic	1.68 (0.86 – 3.29)	1.76 (0.84 – 3.67)
Hispanic	0.98 (0.63 – 1.52)	1.03 (0.63 – 1.67)
Others b	0.81 (0.41 – 1.58)	0.64 (0.31 – 1.31)
Surveillance Site
Arizona	Referent	Referent
Colorado	1.01 (0.60 – 1.70)	0.97 (0.56 – 1.68)
Georgia	1.45 (0.85 – 2.49)	1.07 (0.58 – 1.98)
Iowa	1.08 (0.59 – 1.96)	1.43 (0.73 – 2.81)
Western New York c	1.21 (0.65 – 2.25)	1.33 (0.68 – 2.63)
Age of First Signs and Symptoms
<1.5 years	Referent	Referent
1.5 - < 3.0 years	0.79 (0.45 – 1.37)	0.68 (0.38 – 1.22)
3.0 - <5.0 years	1.42 (0.83 – 2.45)	1.40 (0.80 – 2.45)
5.0+ years	0.92 (0.53 – 1.62)	0.82 (0.45 – 1.48)
Ever Used Cardiac Medicationsd	0.77 (0.52 – 1.16)	1.04 (0.66 – 1.62)
Ever Used Cough Assist Machine d	0.46 (0.28 – 0.75)	0.46 (0.26 – 0.80)
Ever Had Scoliosis Surgery d	0.60 (0.41 – 0.88)	0.47 (0.31 – 0.72)
Ever Used BiPAP Machine d,e	0.76 (0.50 – 1.14)	1.15 (0.71 – 1.86)
Current Glucocorticoid Use d	0.28 (0.11 – 0.69)	0.23 (0.09 – 0.57)

^aAdjusted models were adjusted for all variables listed.

^bOther category includes individuals who were Asian, Native Hawaiian, Pacific Islander, Native American, Alaskan Native, of multiple races or whose race and ethnicity was not documented

^cWestern New York surveillance site included 12 counties

^dTreatment variables were included as time-varying covariates in one-year increments

^eBilevel positive airway pressure