Cost-related nonadherence to prescription medications in Canada: a scoping review

Figures & data

Figure 1 PRISMA flowchart.

Note: *Focused on generic vs branded pricing and prescribing, formulary of public drug programs, prescription auditing, and polypharmacy.

Table 1 Descriptive summary of the studies included in review

Study	Province/country	Population characteristic	Sample size	Study design	Focus of the study	Outcome measurement
Campbell et al^Citation35	Manitoba, Saskatchewan, Alberta, and British Columbia	Adults with chronic conditions	N=1,849	Population-based survey	Financial barriers to care including prescriptions	CRNA defined as stopped taking one or more medications for at least a week in last 12 months due to cost
Hennessy et al^Citation26	Manitoba, Saskatchewan, Alberta, and British Columbia	Adults with chronic conditions	N=1,849	Population-based survey	OOP spending on prescriptions and CRNA	CRNA defined if patients did not get drugs needed due to cost in the past 12 months
Tamblyn et al^Citation29	Quebec	Patients accessing primary care	N=15,961	Retrospective cohort study	Medication nonadherence with CRNA as one of the elements	Nonadherence defined as not filling incident prescription within 9 months
Hunter et al^Citation36	Ontario and British Columbia	Homeless and vulnerably housed adults	N=716	Prospective cohort study	Medication nonadherence with CRNA as one of the elements	CRNA defined as not taking medication prescribed by a doctor because it is too expensive
Kratzer et al^Citation51	Ontario	Adults with chronic conditions	N=2,161,311	Population-based survey	Effects of private drug coverage on prescription use	Drug use was defined as having drugs in the past month, and drug coverage was defined if private insurance covered all or part of the prescription medication cost
Ungar et al^Citation28	Ontario	Children with asthma	N=17,046	Retrospective cohort study using administrative database	Effect of cost-sharing on prescription use	Cost-sharing levels were categorized as: zero cost-sharing, <20% (low cost-sharing), and ≥20% (high cost-sharing)
McLeod et al^Citation58	Pan-Canada	General Canadian population	N=14,430	Population-based survey	Financial burden of prescription drug spending	Catastrophic OOP drug expenditure defined as HHs with drug budget share ≥10%
Després et al^Citation37	Quebec	Non-senior adults with chronic conditions	N=2,872	Retrospective cohort study	Effects of OOP costs on adherence in privately insured patients	Adherence defined as proportion of days covered over 1 year−the number of days supply of the medication during the follow-up period divided by the number of days of follow-up
Després et al^Citation34	Quebec	Non-senior adults with chronic conditions	N=1,933	Retrospective cohort study	Effects of OOP costs on adherence in publicly and privately insured patients	Adherence defined as proportion of days covered over 1 year
Kennedy and Morgan^Citation27	Canada and the USA	Adult American and Canadian population	N=2,980 Canadians and 2,486 Americans	Population-based survey	Compare rates of CRNA for prescription drugs in the USA and Canada	CRNA identified if participant responded yes to “During the past 12 months, was there a time when you did not fill a prescription, or you skipped doses of your medicine, due to cost?”
Thanassoulis et al^Citation38	Quebec, Ontario, and British Columbia	Seniors with chronic conditions	N=67,040	Cohort study using administrative data	Impact of type of drug coverage on medication use	Drug use was determined at 30 days of discharge, stratified by prescription plan in each province
Sanmartin et al^Citation6	Pan-Canada	General population	N=98% Canadians	Population-based survey	Trends in health care expenditure including OOP expenditure on prescription medications	Direct expenditures and insurance premiums for prescription medications Direct expenditures defined as those not covered by insurance, such as exclusions, deductibles, and expenses over limits, and exclude payments for which individuals have been or will be reimbursed
Rotermann et al^Citation33	Pan-Canada	General population	N=11,386	Population-based survey	Determinants of prescription medication use including HH income	Drug use was determined if respondents had taken at least one prescription medication within 2 days of their HH interview
Allin and Hurley^Citation54	Pan-Canada	General population	N=33,161	Population-based survey	Impact of drug coverage on physician utilization	Physician utilization measured by asking if person has seen a family doctor or specialist in last 12 months
Kapur and Basu^Citation56	Pan-Canada	General population	N=n/a	Population-based survey	Extent of drug coverage and financial burden of prescription drugs	Financial burden of prescription drugs calculated as OOP drug expenses of HHs as a proportion of HH income
Law et al^Citation25	Pan-Canada	General population	N=5,732	Population-based survey	Extent and determinants of CRNA	CRNA defined as if costs led people who reported taking medication in past year to do anything to make their prescription last longer, not fill a new prescription or not renew a prescription
Zhong^Citation53	Ontario	General senior and non-senior population	N≥60,000	Population-based survey	Inequality in drug use with respect to income	Drug utilization was determined by asking the participants: “How many different numbers of prescription drugs have you taken in the last 4 weeks?”
Millar^Citation50	Pan-Canada	Senior and non- senior population diagnosed with a chronic disease	N=70,884	Population-based survey	Availability of drug insurance and its effect on prescription drug use	Number of drugs taken in the past month used as an indicator of the influence of drug insurance coverage on medication use
Luffman^Citation57	Pan-Canada	General senior and non-senior population	N≥20,000 HHs	Population-based survey	OOP prescription drug spending across various provinces	OOP drug spending referred to expenditures for medicines, drugs, and pharmaceutical products prescribed by a doctor such as exclusions, deductibles, and expenses over limits
Lee and Morgan^Citation31	Pan-Canada	Senior population	N=5,269	Population-based survey	CRNA and its determinants	CRNA defined as not filling a prescription or skipping doses within the last 12 months because of OOP costs, among those who reported taking at least one prescription
Kemp et al^Citation30	Australia, Canada, the UK, the USA, the Netherlands, New Zealand, Germany	General population	N=8,898	Population-based survey	CRNA and its determinants across countries	Cost-related medication underuse assessed if there was a time in the last 12 months when respondent did not collect a prescription or skipped doses because of the cost? (yes/no)
Hanley^Citation52	Ontario	Non-senior population	N=31,630	Population-based survey	Impact of prescription drug insurance on unmet health care needs	Unmet health care need was identified if participants decided not to seek care because he or she anticipated that a visit to a physician would result in a prescription
Dhaliwal et al^Citation45	Alberta	Individuals with heart disease	N=13	Qualitative study	Experiences of patients who reported financial barriers to care including prescriptions	CRNA was identified if participants shared that they forgo their pills if they cannot afford it
Dewa et al^Citation7	Pan-Canada	Senior and non-senior community- dwelling Canadians	N=33,000	Population-based survey	Characteristics of people covered or not covered for public prescription drug insurance	Having a drug insurance was identified if participant said yes to “Do you have insurance that covers all or part of the costs of your prescription medications?”
Demers et al^Citation10	Pan-Canada	Senior and non-senior individuals including social assistance recipients	N=32* scenarios	Policy analysis	To examine the impact of variation in provincially funded public drug benefits on patients’ prescription drug costs having similar prescription needs	Cost-sharing strategies were examined in the form of premium, deductible, co-payment, and maximum annual contribution by the beneficiary, and pharmacists’ dispensing fees
Kennedy and Morgan^Citation32	Canada and the USA	Adult American and Canadian population	N=8,688	Population-based survey	Extent and determinants of CRNA in two countries	CRNA was measured as failure to obtain prescribed medication due to cost in the prior month
Guilcher et al^Citation43	Pan-Canada	Health care professional, non-health professionals, and policymakers	N=180	Qualitative study	Perspectives of key stakeholders about the availability and use of prescription drugs for neurological conditions	n/a
Wang et al^Citation46	Pan-Canada (Quebec vs rest of Canada)	Canadians between age of 12 and 64	N=10,653	Experimental study	Impact of universal prescription drug insurance on health care utilization and health outcomes	Drug insurance status was determined if a person reported having drug insurance. Measures of health care utilization include drug utilization, physician visits, and hospitalization. Drug utilization measures the number of distinct medications taken in the previous month
Zheng et al^Citation49	Ontario	Patients visiting an outpatient clinic	N=60	Small survey	Predictors leading to CRNA	CRNA was assessed by asking patients to think for last 12 months and describe how frequently they left prescriptions unfilled, delayed filling prescriptions, took prescriptions with reduced frequency, and lowered dosages because of the cost
Goldsmith et al^Citation44	Ontario and British Columbia	Adults engaging in CRNA in past or currently	N=35	Qualitative study	Understand patients’ experiences of CRNA through typology development	CRNA was explored by asking participants’ most recent experience with stopping, reducing, or not filling a prescription medication due to OOP costs
Yao et al^Citation39	Saskatchewan	Seniors with chronic illnesses	N=188,109	Retrospective cohort study	Quantify the impact of drug benefit plan on medication adherence that capped OOP costs at $15 per prescriptions	Adherence was measured over 365 days using medication possession ratio
Assayag et al^Citation40	Quebec	Non-senior patients with depression	N=2,249	Matched cohort study	Adherence between privately and publicly insured patients	Adherence over 1 year was estimated using the proportion of prescribed days covered
Daw and Morgan^Citation42	Pan-Canada	n/a	N=n/a	Analyses of administrative database	Review of provincial drug benefit programs to find factors leading to catastrophic drug expenditures	Assessed premiums and cost-sharing mechanisms in the form of the expenses borne by the patient (or via supplementary private insurance): deductibles, co-payments/co-insurance, and OOP limits to find catastrophic drug expenditures
Anis et al^Citation41	British Columbia	Elderly patients with rheumatoid arthritis	N=2,968	Retrospective cohort study using administrative database	Effect of prescription drug cost-sharing on overall health care utilization	In people who reached the annual maximum co- payment of $200 for any calendar year from 1997 to 2000, the outcomes assessed were number of hospital admissions, the number of physician visits, and the total number of prescriptions filled
Tamblyn et al^Citation47	Quebec	Elderly and welfare recipients	N=93,950 elderly persons and 55,333 adults on welfare	Interrupted time series analysis	Adverse effects of prescription drug cost- sharing on overall health care utilization	Mean number of drugs used per month, ED visits, and hospitalization, nursing home admission, and mortality before and after policy introduction
Lexchin and Grootendorst^Citation48	Industrialized countries including Canada	Vulnerable population	N=25 studies	Systematic review of literature	Effects of user fees for prescription drugs on drug use, other health services use, and overall health status	User fee included costs that patients pay OOP for prescriptions such as in the form of co-payment, deductibles, reimbursement limits, etc.
Law et al^Citation55	Pan-Canada	General population	N=28,091	Population-based survey	Consequences for prescription drug costs	Health consequences that led to use of additional health care services such as a doctor visit or ER visit, and other consequences leading to trade-offs between prescriptions and other basic needs

Note:

* Number of case scenarios.

Abbreviations: CRNA, cost-related nonadherence; OOP, out-of-pocket; HH, household; ED, emergency department; ER, emergency room; n/a, not available.

Table 2 Extent of cost-related nonadherence to prescription medications

	Extent	Population	Province	Study
1	9.6% reported CRNA to medications ranging from 3.6% (95% CI 2.4–4.5) to 35.6% (95% CI 26.1–44.9) depending on income and availability of insurance	General population	Pan-Canada	Law et al^Citation25
2	8.2% reported CRNA to medications who were prescribed at least one medication in last 12 months	General population	Pan-Canada	Law et al^Citation55
3	8.3% Canadians aged 55 years and older reported CRNA to medications	Senior population	Pan-Canada	Lee and Morgan^Citation31
4	15% reported CRNA to medications	Patients visiting outpatient clinic	Ontario	Zheng et al^Citation49
5	Prevalence of CRNA between privately and publicly insured individuals was 14% and 18%, respectively	Non-senior patients with depression	Quebec	Assayag et al^Citation40
6	4.1% reported CRNA to medications	Adults with chronic conditions	Manitoba, Saskatchewan, Alberta, and British Columbia	Hennessy et al^Citation26
7	13% reported stopped taking medications in last 12 months at least for a week due to cost	Adults with chronic conditions	Manitoba, Saskatchewan, Alberta, and British Columbia	Campbell et al^Citation35
8	31.3% of the incident prescriptions were not filled in the last 9 months	Patients accessing primary care	Quebec	Tamblyn et al^Citation29
9	26% reported nonadherence to prescriptions	Homeless and precariously housed adults	Ontario and British Columbia	Hunter et al^Citation36

Abbreviation: CRNA, cost-related non-adherence.

Table 4 Impact of cost-related nonadherence to prescription medications

	Impact/consequences	Population	Province	Study
1	Relative to those with no drug insurance, the insured make more use of physician services after controlling for need of seeking care	General population	Pan-Canada	Allin and Hurley^Citation54
2	People without prescription drug insurance were more than twice as likely as those with insurance to report an unmet need for health care	Non-senior population	Pan-Canada	Hanley^Citation52
3	Introduction of the mandatory drug coverage program increased medication use and GP visits. No statistically significant effects were found for specialist visits and hospitalization	Canadians between age of 12 and 64	Pan-Canada	Wang et al^Citation46
4	Across the 4 years, there were 0.38 more physician visits per month, 0.50 fewer prescriptions filled per month, and 0.52 fewer prescriptions filled per physician visit, during the cost-sharing period than during the free period. Among patients who were admitted to the hospital at least once, there were 0.013 more admissions per month during the cost- sharing period than during the free period	Elderly patients with rheumatoid arthritis	British Columbia	Anis et al^Citation41
5	After co-payments were introduced, the number of prescription drugs used per day decreased by 9% among older people and by 16% among those receiving social assistance; these reductions were associated with an increased rate of emergency department visits by 14.2 and 54.2 events per 10,000 person-months, respectively	Elderly and welfare recipients	Quebec	Tamblyn et al^Citation47
6	Cost-sharing leads patients foregoing essential medications and to a decline in health care status. Co-payments or a cap on the monthly number of subsidized prescriptions lower drug costs for the payer, but any savings offset by increases in other health care areas	Vulnerable population	OECD countries including Canada	Lexchin and Grootendorst^Citation48
7	Many Canadians forewent basic needs such as food (about 730,000 people), heat (about 238,000), and other health care expenses (about 239,000) because of drug costs	General population	Pan-Canada	Law et al^Citation55
8	Some participants identified that their CRNA led to adverse clinical outcomes. Some of them also “separated” medications into essential and nonessential categories and prioritized medications over healthy food	Individuals with heart disease	Alberta	Dhaliwal et al^Citation45
9	Self-reported financial barriers to drugs were not found significantly associated with increased number of emergency department visits or hospitalizations, though patients facing financial barriers to take medications were 50% less likely to take medications	Adults with chronic conditions	Manitoba, Saskatchewan, Alberta, and British Columbia	Campbell et al^Citation35

Abbreviations: GP, general practitioner; OECD, Organisation for Economic Co-operation and Development; CRNA, cost-related non-adherence.

Table 3 Factors associated with cost-related nonadherence

	Factors	Studies
1	Low income or lack of regular employment (n=15)	Hennessy et al;^Citation26 Sanmartin et al;^Citation6 Rotermann et al;^Citation33 Kapur and Basu;^Citation56 Law et al;^Citation25,Citation55 Zhong;^Citation53 Millar;^Citation50 Lee and Morgan;^Citation31 Kemp et al;^Citation30 Dewa et al;^Citation7 Kennedy and Morgan;^Citation32 Guilcher et al;^Citation43 Goldsmith et al;^Citation44 Daw and Morgan^Citation42
2	Young age (non-senior) (n=12)	Tamblyn et al;^Citation29 Hunter et al;^Citation36 Kennedy and Morgan;^Citation27,Citation32 Kapur and Basu;^Citation56 Millar;^Citation50 Lee and Morgan;^Citation31 Kemp et al;^Citation30 Dewa et al;^Citation7 Guilcher et al;^Citation43 Yao et al;^Citation39 Law et al^Citation55
3	Multiple comorbidities, chronic illness, severe illness, or poor health status (n=10)	Hennessy et al;^Citation26 Tamblyn et al;^Citation29 Kratzer et al;^Citation51 Kennedy and Morgan;^Citation27,Citation32 Law et al;^Citation25,Citation55 Millar;^Citation50 Lee and Morgan;^Citation31 Kemp et al^Citation30
4	High out-of-pocket expenditure on drugs, and expensive or costly drugs (n=10)	Campbell et al;^Citation35 Hennessy et al;^Citation26 Tamblyn et al;^Citation29 Ungar et al;^Citation28 Després et al;^Citation37 Kemp et al;^Citation30 Zheng et al;^Citation49 Goldsmith et al;^Citation44 Daw and Morgan;^Citation42 Demers et al^Citation10
5	No drug insurance (n=9)	Rotermann et al;^Citation33 Law et al;^Citation25,Citation55 Zhong;^Citation53 Millar;^Citation50 Lee and Morgan;^Citation31 Kennedy and Morgan;^Citation32 Zheng et al;^Citation49 Goldsmith et al^Citation44
6	Province of residence (n=7)	McLeod et al;^Citation58 Thanassoulis et al;^Citation38 Kapur and Basu;^Citation56 Law et al;^Citation25,Citation55 Luffman;^Citation57 Daw and Morgan^Citation42
7	Having public drug insurance vs private insurance (n=5)	Kratzer et al;^Citation51 Després et al;^Citation34 Kemp et al;^Citation30 Lee and Morgan;^Citation31 Zheng et al^Citation49
8	Race and ethnicity: immigrant or aboriginal status, or being non-white (n=3)	Law et al;^Citation55 Dewa et al;^Citation7 Zhong^Citation53
9	Not having a primary physician (n=3)	Hunter et al;^Citation36 Tamblyn et al;^Citation29 Kennedy and Morgan^Citation32
10	Women (sex) (n=2)	Kennedy and Morgan;^Citation27 Law et al^Citation55
11	Less education (n=2)	Kapur and Basu;^Citation56 Zhong^Citation53
12	Living alone or not having spouse or partner (n=2)	Kapur and Basu;^Citation56 Dewa et al^Citation7
13	Living in a rural area (n=1)	Kapur and Basu^Citation56

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