The Impact of Comorbid Depression on Adherence to Therapy for Multiple Sclerosis

Table 4

Ordinary least squares regression results dependent variable: MPR.

Variable	MS Only versus MS & Depression		Dx Depression versus Dx & Rx Depression		Rx Depression- ≥6 Mo Antidepressants versus <6 Mo
	Coeff	𝑃 value	Coeff	𝑃 value	Coeff	𝑃 value
Intercept	0.71	<0.001	0.64	0.047	0.47	<0.001
Insurance type^a
HMO	−0.10	0.022	−0.14	0.509	-0.16	0.200
POS	−0.02	0.665	−0.07	0.731	0.02	0.901
PPO	0.01	0.890	0.12	0.491	0.02	0.860
Other	−0.002	0.974	−0.27	0.523	0.08	0.693
Medication dispensing
Copayment	0.06	0.047	−0.06	0.680	0.10	0.213
Mail order	0.05	0.051	0.02	0.909	0.08	0.216
Preperiod Charlson score^b
1-2	0.01	0.738	0.09	0.521	0.06	0.379
3+	−0.04	0.467	0.04	0.853	0.09	0.422
Preperiod ADL proxies
Musculoskeletal	0.02	0.440	−0.03	0.828	0.06	0.294
Medical	0.02	0.448	0.10	0.419	−0.01	0.889
Preperiod depression
Any	−0.10^c	<0.001	—	—	—	—
Dx & Rx	—	—	0.07^d	0.518	—	—
Rx for at least 6 months	—	—	—	—	0.12^e	0.049
Adjusted 𝑅^2	0.05		0.08		0.06

^aReference group: Comprehensive insurance.
^bReference group: Charlson score of 0.
^cReference group: patients with MS and no diagnosis of depression or receipt of an antidepressant.
^dReference group: patients diagnosed with depression who did not receive an antidepressant.
^eReference group: patients diagnosed with depression who were treated with an antidepressant for less than 6 months.