dates and claim types available in each province

1 Supplementary Tables

Table e-1| Health Administrative Data – dates and claim types available in each province Province Unique

Identifier

Physician Claims Hospital Claims Prescription Claims MS-specific Clinical Database

British Columbia

Personal Health Number (PHN)

 Dates only available from 1985/1986 onward

 ICD-9 4 digit code included in data file from 1991-92 onward

 One diagnosis

 Available from 1985/1986 onward

 ICD-9 coding changed to ICD-10 in 2001

 Up to 25 diagnosis codes

 PharmaNet: Available from 1996 onward

 Includes drug, quantity, dose, directions, days’

supply, dates for fills and physician specialty

 The BC MS database captured approximately 80% of MS patients in BC until the end of 2004; the last year all MS Clinics in the province participated.

Nova Scotia Medical Services Identification (MSI) Number

 Available from 1989 onward

 ICD-9 3-digit coding

 One diagnosis from 1989 to 1996

 Three diagnoses from 1997 to 2006

 Available from 1989 onward

 5 digit ICD-9 coding changed to ICD-10-CA coding in 2001

 Up to 5 diagnoses 1989-1991, 7 diagnoses 1992-1995, 16 diagnoses 1996 onward

 Use of a DMD, starting and stopping dates are included in the NS

MS-specific clinical data.

 (Outpatient prescription database is not available in NS)

 Database of the Dalhousie Multiple Sclerosis

Research Unit (DMSRU) was the sole specialized MS clinic and provider for provincially funded DMD in NS; data captured approximately 85% of the NS MS population and 100% of those taking DMT.

2 Table e-2 | Selection of study patients for the main analyses

aBritish Columbia (1991-2008),

n=1,861

Nova Scotia (1990-2010),

n=1,305

Total, n=3,166 Main analysis

Patients clinically definite MS,≥18 years at entry and onset date available 2,396 1,507 3,903 Exclusion criteria for main analysis

 Registered for <270 days during the baseline year 358 202 560

 EDSS and/or clinic visit date unavailable during follow-up 177 0 177

aThe BCMS clinical dataset for this study was available for those MS patients who were first registered with an MS clinic in BC by end/2004 (this population-based cohort was then followed to end/2008).

3 Table e-3 | Comorbidity diagnosis and drug treatments^22-24

Comorbidity First 3 digits of ICD-9 codes

First 3 digits of ICD-10 codes

ATC codes

Chronic lung disease 493, 491, 492, 496 J45, J46, J40, J42, J43, J44 R03 (oral and inhaled beta-adrenergic agonists, inhaled corticosteroids, leukotriene inhibitors, xanthine derivatives, ipratropium, and mast cell stabilizers)

Epilepsy 345 G40, G41 N03AA02 (Phenobarbital), N03AA03 (primidone),

N03AB02 (phenytoin), N03AD01 (ethosuximide), N03AF01 (carbamazepine), N03AF02 (oxcarbazepine),

N03AG01 (valproic acid), vigabatrin (N03AG04), N03AX09 (lamotrigine), N03AX12 (gabapentin), N03AX14 (levetiracetam), N03AX15 (pregabalin),

4 N05BA09 (clobazam)

Diabetes 250 E10-E14 A10 (drugs used in diabetes)

Hypertension 401-405 I10-I13, I15 C02 (anti-hypertensives), C03 (diuretics), C07

(beta-blockers), C08 (calcium channel blockers), and C09 (agents acting on the rennin-angiotensin system)

Hyperlipidemia 272 E780, E782, E784, E785 C10 (lipid modifying agents)

Ischemic heart disease 410-414 I20-I25 C01 (cardiac therapy), C07 (beta-blockers), C08

(calcium channel blockers), and C09 (agents acting on renin-angiotensin system)

Abbreviation: ICD: International Classification of Diseases; ATC: the Anatomical Therapeutic Chemical Classification System

5 Table e-4 | The relationship between comorbidity, its drug treatment status and disability progression in British Columbia, Canada

Comorbidity by drug treatment status Unadjusted coefficients and 95% CI Adjusted coefficients and 95% CIs Chronic lung disease

Absent 1 1

Present, with treatment 0.54 (0.02, 1.06) 0.50 (-0.40, 1.03) Present, without treatment 0.18 (-0.18, 0.54) 0.17 (-0.19, 0.54) Diabetes

Absence 1 1

Present, with treatment 0.69 (0.05, 1.32) 0.33 (-0.36, 1.01) Present, with no treatment 0.02 (-0.41, 0.45) -0.20 (-0.70, 0.29) Epilepsy

Absence 1 1

Present, with treatment 0.73 (0.26, 1.20) 0.41 (-0.12, 0.94) Present, with no treatment 0.68 (0.19, 1.17) 0.39 (-0.16, 0.94) Hyperlipidemia

Absence 1 1

Present, with treatment 0.60 (-0.07, 0.28) -0.08 (-0.85, 0.69) Present, with no treatment 0.49 (0.08, 0.90) -0.02 (-0.47, 0.42) Hypertension

Absence 1 1

Present, with treatment 0.85 (0.54, 1.16) 0.20 (-0.12, 0.51) Present, with no treatment 0.55 (0.24, 0.86) 0.06 (-0.25, 0.37) Ischemic heart diseases

Absence 1 1

Present, with treatment 0.52 (-0.001, 1.03) 0.29 (-0.25, 0.83)

6 Present, with no treatment 0.74 (0.28, 1.19) 0.33 (-0.11, 0.77)

Note: Results were obtained from generalized estimate equation models. Sex, disease course, cohort entry year and SES were included in each of the adjusted models. Age was the time scale.