Comparative Risk of Harm Associated with Zopiclone or Trazodone Use in Nursing Home Residents: a Retrospective Cohort Study in Alberta, Canada

. 2023 Mar 1;26(1):9–22. doi: 10.5770/cgj.26.622

Variable	Database Source	Codes	Algorithm
DEMOGRAPHICS

Age	Provincial Registry	NA	patient’s age at index date

Sex	Provincial Registry	NA	patient’s sex at index date

Year of cohort entry	PIN	NA	year of index date

Weight	Alberta CCIS	K2B	from most recent non-missing RAI assessment prior to index date

Receiving palliative care	CIHI-DAD	ICD10: Z515 or patserv=58	any code in past 180 days prior to index date
	Practitioner Registry	03.05I, 03.05T, 03.05U
	Alberta CCIS	P1AO=1

Wheelchair ambulation	Alberta CCIS	G5B=1, G5C=1, G5D=1	any 1 code from RAI assessment ≤45 days prior to index date

MEDICAL HISTORY

Alcohol use	CIHI-DAD	ICD9: 303,305	any 1 code
	CIHI-DAD	ICD10: E244, E512, F10, G312, G621, G721, I426, K292, K70, K860, T510, X45, X65, Y15, Y573, Z502, Z714, Z721	any 1 code
	Practitioner Registry	291, 303	any 2 codes

Atrial fibrillation/flutter	CIHI-DAD or NACRS	ICD9: 427.31, 427.32	1 CIHI-DAD/NACRS code OR 1 PIN claim for “Antiarrhythmics” (****correction: instead of 1 PIN claim) OR 1 practitioner registry claim for cardioversion [Z437] OR (PIN claim for anticoagulant + 1 practitioner registry code)
	CIHI-DAD or NACRS	ICD10: I48
	Practitioner Registry	427, 49.98X
	PIN	see “Antiarrhythmics” and “Anticoagulants”

Cerebrovascular disease	CIHI-DAD	ICD10: 160.x (exclude 160.8), 161.x, 163.x (exclude 163.6), H34.1, 164.x, H34.0, G45.x (exclude G45.4)	any 1 code in DAD most responsible diagnosis position
Cerebrovascular disease	Alberta CCIS	I1U	any 1 code

Delusions/hallucinations	Alberta CCIS	J1E=1, J1I=1	any 1 code (from most immediately antecedent RAI assessment prior to index date)

Dementia	CIHI-DAD	ICD9: 46.1, 290.0, 290.1, 290.2, 290.3, 290.4, 294.x, 331.0, 331.1, 331.5, 331.82	3 Practitioner registry codes at least 30 days apart in a 2 year period OR 1 PIN claim OR 1 CIHI-DAD code
	CIHI-DAD	ICD10: F00x, F01x, F02x, F03x, G30x
	Practitioner Registry	290, 331
	PIN	see “Cholinesterase Inhibitors”
	Alberta CCIS	I1V=1, I1R=1, P1AN=1	any 1 code

Depression	CIHI-DAD	ICD10: F32.0, F32.1, F32.2, F32.3, F32.4, F32.5, F32.8, F32.9, F33.0, F33.1, F33.2, F33.3, F33.41, F33.42, F33.8, F33.9, F34.1, F34.8, F34.9, F38.0, F38.1, F38.8, F39, F41.2	any 1 code
	Practitioner Registry	311	≥1 psychiatrist codes OR ≥2 family physician codes within 2 years for any ICD10 depression diagnoses in CIHI-DAD (see above)
	Alberta CCIS	I1GG=1	any 1 code

Diabetes mellitus	CIHI-DAD	ICD9: 250.x	any 1 code
	Practitioner Registry	250	any 2 codes in a 2-year period
	Alberta CCIS	I1a=1	any 1 code

Injurious falls	NACRS or CIHI-DAD	ICD10: W00-W19	Any 1 code in last year prior to index date

Hearing impairment	Alberta CCIS	C1=1,2,or3; C2A=1;C2B=1;C2C=1	Any 1 code

Heart failure	CIHI-DAD	ICD9: 428	Any 1 code
	CIHI-DAD	ICD10: I500, I501, I509	Any 1 code
	Practitioner Registry	428	Any 1 code + 2nd claim from CIHI-DAD or practitioner registry in 1 year
	Alberta CCIS	I1f=1	Any 1 code

Hypertension	Practitioner Registry	ICD9: 401x, 402x, 403x, 404x, 405x	Any 2 outpatient codes within 3 years
	Practitioner Registry	ICD10: I10x, I11x, I12x, I13x, I15x
	CIHI-DAD	ICD9: 401x, 402x, 403x, 404x, 405x
	CIHI-DAD	ICD10: I10x, I11x, I12x, I13x, I15x
	Alberta CCIS	I1i=1	Any 1 code

Ischemic heart disease	Practitioner Registry	410, 412, 413, 48.12, 48.13, 48.14, 48.15, 51.61C, 51.59B, 51.59D, 51.59E, 51.59F	Any 2 codes (with 1 being in a hospital or emergency room setting) in a 1 year period
Ischemic heart disease	CIHI-DAD	CCI: 1IJ50, 1IJ57GQ, 1IJ76	Any 1 code

Kidney disease (chronic)	Alberta CCIS	P1AB=1	any 2 codes

Liver disease (chronic)	Alberta CCIS	I1TT=1	any 1 code

Major Osteoporotic Fracture	CIHI-DAD	ICD10: S321, S322, S323, S324, S325, S327, S328, S422, S432, S424, S720, S721; CCI 1VA53, 1VA73, 1VA74, 1VA80, 1VC73, 1VC74	any 1 code
	Practitioner Registry	91.00A-E, 91.01, 91.04A-C, 91.08L, 91.08J, 91.10, 91.14, 91.30, 91.31, 91.34	any 2 codes
	Alberta CCIS	J4C, I1M	any 1 code

Malignancy	Alberta CCIS	I1RR=1, P1AA=1, P1AH=1	any 1 code

Myocardial Infarction	CIHI-DAD or NACRS	ICD9: 410, 412	any 3 practitioner registry codes in 1 year (with at least one being by a specialist [i.e., not a family doctor] OR within a hospital or emergency room) + any one CIHI-DAD code
	CIHI-DAD or NACRS	ICD10: I21, I22, I25.2
	Practitioner Registry	ICD9: 410, 412
	Practitioner Registry	ICD10: I21, I22, I25.2

Osteoporosis	CIHI-DAD	ICD9: 733.01–733.09	any 1 code in 5 years prior to index date
	CIHI-DAD	ICD10: M80, M81, M82	any 1 code in 5 years prior to index date
	PIN	See “Osteoporosis Medications”	any 1 code
	Practitioner Registry	733	any 1 code in 5 years prior to index date
	Alberta CCIS	I1O=1	any 1 code

Parkinsonism	CIHI-DAD	ICD9: 332.0, 332.1	don’t use; algorithm is best with Practitioner Registry codes - many other algorithms if needed
	CIHI-DAD	ICD10: G20, G21.0, G21.1, G21.2, G21.3, G21.4, G21.8, G21.9, G22, F02.3
	Practitioner Registry	332	any 2 practitioner registry codes in 1 year separated by 30 days
	Alberta CCIS	I1AA=1	any 1 code

Peripheral vascular disease	Alberta CCIS	I1J=1	any 1 code

Psychoses (chronic)	CIHI DAD	ICD10: F20, F25, F29	any 1 CIHI-DAD code or 2 practitioner registry codes within 5 years
	Practitioner Registry	295, 298
	Alberta CCIS	I1II=1	any 1 code

Rheumatoid arthritis	CIHI-DAD	ICD9: 714	any 1 code
	CIHI-DAD	ICD10: M05-M06	any 1 code
	Practitioner Registry	714	any 3 codes with ≥1 by a specialist (specialist = rheumatologist, internist, or orthopedic surgeon) within 2 years

Seizure disorder	CIHI-DAD	ICD9: 345	any 1 code
	CIHI-DAD	ICD10: G40.x, G41.x	any 1 code
	Practitioner Registry	345	3 codes separated by 30 days
	Alberta CCIS	I1CC=1	any 1 code

Unsteady gait	Alberta CCIS	J1N=1, G5A=1, G6B=1, G6C=1, G6D=1, G6E=1	any 1 code

Visual impairment	Alberta CCIS	D1=1,2,3,or 4; D2A=1;D2B=1;D3=1	any 1 code

HEALTH-CARE UTILIZATION ^a

Number of inpatient hospitalizations	CIHI-DAD	NA	Use %getdadsds to pull all hospitalization admissions (parameter source = inpat; parameter refdate = admdate) in the year prior to index date. To exclude hospital transfers, only keep one hospitalization record for each unique hospitalization episode (variable epi). Count the number of inpatients admissions for each cohort member.

Number of drugs prescribed	PIN	NA	Use %getodb to pull all ODB records (including records without the LTC flag) in the year prior to index date. Count the number of unique dins for each cohort member.

Number of emergency room visits	NACRS	NA	Use %getnacrs to pull all unscheduled ED records (parameter inclscheduled = F) in the year prior to index date. Exclude records that constitute a transfer from one ED to another ED (where From_Type = ‘E’). Count the number of ED visits for each cohort member.

Number of geriatrician visits	Practitioner Claims	SPECNAM = (“GERIATRICS”)	Count only one visit per person per day per physician. For each patient, sum the total number of visits made in the past year.

Number of psychiatrist visits	Practitioner Claims	SPECNAM = (“PSYCHIATRY”)	Count only one visit per person per day per physician. For each patient, sum the total number of visits made in the past year.

PERFORMANCE SCALES

Cognitive performance scale	Alberta CCIS	B1=0,1; B4=0,1,2,3; G1h=0,1,2; B2a=0,1; C4=0,1,2,3	from RAI assessment ≤45 days prior to index date

Dependency in ≥1 activities of daily living (ADL)	Alberta CCIS	G1a=1,2,3, or 4; G1b=1,2,3, or 4; G1c=1,2,3, or 4; G1d=1,2,3, or 4; G1e=1,2,3, or 4; G1f=1,2,3, or 4; G1g=1,2,3, or 4; G1h=1,2,3, or 4; G1i=1,2,3, or 4; G1j=1,2,3, or 4; G2=1,2,3 or 4	any 1 code equal to 1, 2, 3, or 4 from (one of G1a,G1b,G1c,G1d,G1e, G1f) OR G1g, G1h, G1i, G1j, G2 (from RAI assessment ≤30 days prior to index date)

Dependency in ADLs (mean, SD)	Alberta CCIS	G1a=1,2,3, or 4; G1b=1,2,3, or 4; G1c=1,2,3, or 4; G1d=1,2,3, or 4; G1e=1,2,3, or 4; G1f=1,2,3, or 4; G1g=1,2,3, or 4; G1h=1,2,3, or 4; G1i=1,2,3, or 4; G1j=1,2,3, or 4; G2=1,2,3 or 4	if (G1a=1,2,3, or 4) OR (G1b=1,2,3, or 4) OR (G1c=1,2,3, or 4) OR (G1d=1,2,3, or 4) OR (G1e=1,2,3, or 4) OR (G1f=1,2,3, or 4) then patient is dependent for mobility (mobility=1); if G1g=1,2,3, or 4 then dressing=1; if G1h=1,2,3, or 4 then eating=1; if G1i=1,2,3, or 4 then toilet=1; if G1j=1,2,3, or 4 then hygiene=1; if G2=1,2,3 or 4 then bathing=1; sum of mobility + dressing + eating + toilet + hygiene + bathing = dependency in ADLs (from RAI assessment ≤30 days prior to index date)

Depression symptom scale	Alberta CCIS	E1a=0,1,2; E1d=0,1,2; E1f=0,1,2; E1h=0,1,2; E1i=0,1,2; E1l=0,1,2; E1m=0,1,2	from RAI assessment ≤45 days prior to index date

Aggressive behaviour scale	Alberta CCIS	E4b=0,1,2,3; E4c=0,1,2,3; E4d=0,1,2,3; E4e=0,1,2,3	from RAI assessment ≤45 days prior to index date

OUTCOMES

Major osteoporotic fracture	NACRS or CIHI-DAD	ICD 10: S321, S322, S323, S324, S325, S327, S328, S422, S432, S424, S720, S721; CCI 1VA53, 1VA73, 1VA74, 1VA80, 1VC73, 1VC74	admission date (admdate) is within 180 days following index date; combine NACRS and DAD records and keep the record for the first (earliest) fracture within the 180 day follow-up period.
Major osteoporotic fracture	Practitioner Claims	91.00A-E, 91.01, 91.04A-C, 91.08L, 91.08J, 91.10, 91.14, 91.30, 91.31, 91.34	any 2 codes within the 180 day follow-up period

Injurious fall	NACRS or CIHI-DAD	ICD 10: W00-W19	admission date (admdate) is within 180 days following index date; combine NACRS and DAD records and keep the record for the first (earliest) fall within the 180 day follow-up period.

For all hospitalizations using DAD defined above, use:

DAD source: inpatient; Diagnosis type: All diagnosis types except where specifically indicated otherwise;

Exclude suspected diagnoses.

Data Sources

The Alberta Continuing Care Information System (CCIS) contains comprehensive information about residents of nursing homes, including their functional dependence, severity of cognitive impairment, and symptoms relating to depression and pain. Dispensed prescription medications were identified in the Pharmacy Information Network (PIN). The Canadian Institute for Health Information Discharge Abstract Database (CIHI-DAD) was used to identify all inpatient hospitalizations. The National Ambulatory Care Reporting System (NACRS) database was used to identify all emergency department visits. All information relating to physician payment claims was obtained from the Practitioner Claims database. All patient demographic information (including date of death, if appropriate) was obtained from the Provincial Registry.