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Prepared for EvidenceNetwork.ca by Neeta das McMurtry

Can too much healthcare be bad for your health?

Does more healthcare create better outcomes?  In other words, do more medications, tests and interventions necessarily result in healthier patients?

It turns out more care is, all too often, unnecessary care.  For example, appropriate care would be getting antibiotics for an infection caused by bacteria. Getting antibiotics for a viral infection that is not helped by antibiotics — such as the common cold — would be unnecessary care.

A variety of factors determine whether a patient receives more health services, such as patient illness severity and physician clinical judgment. But non-medical factors also play a role including: a medical culture that promotes testing and interventions regardless of necessity; fee-for-service structures that reward volume rather than quality; and availability of healthcare resources such as hospital beds and specialists.  Patient demand, often influenced by the internet and advertising, is also important.

Until recently, there has not been a lot of Canadian-based research examining the possible over-use of healthcare, but this is changing:

  • Findings from long-term U.S. studies on healthcare distribution are stimulating Canadians to look at similarities and differences in our own clinics and hospitals.
  • International work on medical screening is informing our cancer screening debate.
  • Provincial economic pressures are precipitating a closer examination of where diagnostic tests are over-prescribed.

It is counter-intuitive to discover that less healthcare is sometimes better when, for so long, our medical culture has largely assumed that more care is always better.  Patients generally overestimate the benefits, underestimate the harms, and undergo more medical treatments as a result.  But more and more professional organizations across Canada are clearly stating too much healthcare can indeed be bad for your health — and the evidence is mounting.

Hospitals and Clinics

For more than 20 years, the Dartmouth Atlas Project has tracked huge variations in the distribution and use of healthcare resources in the U.S.  These studies consistently show that deploying more resources (e.g., specialist visits, diagnostic tests, hospital care) for similar patients does not necessarily lead to better care.  In fact, insisting on more healthcare can lead to harm. Instead, safely adopting more conservative practices could save the U.S. 30% of Medicare costs, with patient outcomes remaining at least as good or better.

While these findings can inform Canada’s healthcare discussion, direct comparisons are limited because Canada spends one half to one third less on healthcare than the U.S. and our funding models are quite different.

When it comes to comparing hospitals, some Canadian hospitals do spend more than their U.S. counterparts, but they are typically large, teaching hospitals offering specialized cardiac services or associated with regional cancer centres. Also, research shows Canadians may be using hospital funds more efficiently than American hospitals for acute illnesses requiring specialized care and technology.

But that doesn’t mean the Canadian health system doesn’t have problems with unnecessary care as well.

We know that Canadian patients experience large regional variations in the provision of healthcare for conditions such as cardiac disease, stroke, arthritis, asthma and diabetes.  Also, there are a significant number of Canadians using multiple physicians, being referred to multiple specialists, undergoing unnecessary tests or experiencing poorly-coordinated care.  One study has quantified patients’ use of multiple physicians in British Columbia and another study has examined the costs associated with family physicians requesting more diagnostic procedures.  What these studies, and other research has indicated, is that the replication of services and potentially unnecessary care is costing Canadians millions of dollars.

Whether driven by patient well-being or a desire for sustainable economics, the movement to reduce unnecessary medical interventions is gaining momentum, particularly in the areas of screening and testing.  For example, Choosing Wisely Canada partners with professional medical associations across the country in an on-going campaign to “reduce unnecessary medical tests, treatments and procedures.”  They offer online resources on a variety of medical topics to inform both doctors and patients. (See more below in Medical Screening, The PSA Test and Medical Tests.)

Other initiatives include the IMPROVE program, which was piloted in Manitoba and has shown measurable success in improving physicians’ prescribing behaviours.  The program takes advantage of Manitoba’s centralized prescribing database that records prescriptions from community pharmacies.  If an unsafe pattern of medications is spotted in the database, the program summarizes current medical evidence related to the case and sends it to the doctor to help inform his or her practice.  Doctors who received these educational packages significantly reduced potentially inappropriate prescriptions such as sleeping pills and sedatives.

Last year, the Good Stewardship Working Group published ‘Top Five’ lists of potentially unnecessary care for doctors practicing family, internal and paediatric medicine to promote the concept “Less is More.”  They list the top five tests, medications or actions a doctor may view as routine, but actually should be avoided unless special circumstances arise.  For example, family practitioners are provided with guidelines for minimizing the use of imaging and screening tests, and are reminded not to routinely prescribe antibiotics.  Pediatricians are reminded to minimize radiation exposure in children by avoiding head scans and asked to discourage the use of cough and cold medications because they may have significant risks for children. Internists are given guidelines for reducing lower-back imaging and are reminded to only prescribe the more expensive brand-name drugs for managing cholesterol if the generic brands are unsuccessful.

These ‘Top Five’ lists aim to conserve healthcare resources in areas that are known to be consistently over used.  Family physicians, internists and paediatricians are important to target because they are often a patient’s first healthcare contact, a principal point of continuing care and a potential gateway to other specialist care.  Two of the areas highlighted where healthcare services could be reduced in order to both benefit patients and save healthcare costs, are medical screening and diagnostic tests.

Medical Screening 

Medical screening is used to identify disease in populations before they have shown any signs or symptoms.  Some medical screening is supported by strong evidence, such as testing for colon or cervical cancer in recommended populations.  But many other types of medical screening lead to false alarms and potentially risky interventions.

Choosing Wisely Canada, along with experts in oncology, has compiled four top-ten lists to help doctors and patients re-evaluate cancer screening and cancer care protocols together.  Recommendations include restricting pap smears and mammography to certain ages and populations and re-evaluating screening in asymptomatic patients.

The PSA Test

The PSA screen tests a man’s blood looking for risks of prostate cancer.  A high PSA score could mean cancer, but could also be caused by many other things and cannot identify what type of cancer may be present.  This latter point is important because the slow-growing type of prostate cancer is something most men eventually get and won’t die from, but the fast-growing type of cancer can be quickly lethal.

A study published in the New England Journal of Medicine shows that if 1,410 men were screened, only one man would be saved from lethal prostate cancer, 48 men would undergo treatment (with chemotherapy, surgery or drugs) and about 30 men would end up impotent or incontinent as a consequence of treatment.  Research like this prompted the American Urological Association (AUA) to recommend against PSA screening in men aged 40 to 54 years who are at average risk for the disease, which is a reversal of its previous position.

A 2014 review of current evidence advises clinicians to discuss the pros and cons of PSA screening with average-risk men aged 55 to 69 years so that patients can make an informed decision about PSA testing. Other strategies to mitigate the potential harms of screening include considering less-frequent screening, a higher PSA threshold for biopsy and opting for less-invasive therapies for men with a first-time diagnosis of prostate cancer.

Choosing Wisely Canada explains the side-effects of treating prostate cancer and why some types of prostate cancer are better left aloneThey also offer guidelines under “Urology Top 5” that discourage routine bone and pelvic scans for low-risk prostate cancers. 


Screening for some breast cancers is another example where health benefits may have been exaggerated. The Canadian Breast Cancer Foundation and the Canadian Association of Radiologists still advocate population-wide screening of women for breast cancer even though the recent Canadian Task Force on Preventive Health Care recommends not routinely screening women aged 40-49 with mammography.  The Task Force also states that screening the 50-69 year age group is “weak based on moderate-quality evidence.” Their recommendation for screening women aged 70-74 is “weak based on low-quality evidence.”

Population screening refers to routine mammography for healthy women who show no reason for concern (no symptoms or family history of the cancer), so that any early signs may be detected.  This is distinct from diagnostic mammography for women with symptoms of breast cancer or for those who have other high risk factors such as a genetic or familial predisposition.  More specifically, the Canadian Task Force guidelines say individuals who have a personal history of breast cancer, a history of premenopausal breast cancer in their first degree relative (mother or sister), those with a known BRCA1/BRCA2 gene mutation, or prior chest wall radiation should have regular diagnostic mammography.

The two main problems with mammography screening are:

  • A large number of false positives.

(This inevitably leads to further imaging — more mammography, ultrasounds and even MRIs — and, in many cases, surgical biopsy.)

(This typically includes chemotherapy, radiotherapy and may include breast removal.  Besides discomfort, well-established consequences of radiation treatment include the increased risk of other cancers and myocardial damage.)

A review by the Cochrane Collaboration shows that screening 2,000 women regularly for 10 years may prolong one woman’s life. Of the other 1,999 women, at least 200 will have false-positive mammograms leading to biopsies (which turn out not to detect cancer), and at least 10 women will be falsely diagnosed with breast cancer and consequently subjected to unnecessary surgery, radiotherapy and chemotherapy.

A recent Norwegian study shows 15-20 per cent of breast cancer cases are over-diagnosed through routine mammography screening (that is 6-10 women were over-diagnosed and treated for breast cancer which they didn’t have, for every 2500 women screened).  Furthermore, authors of this study call for serious efforts to reduce the frequency of over-diagnosis.

The Canadian National Breast Cancer Screening Study tracked 90,000 women aged 40-59 for 25 years, who were randomly allocated to either the mammography screening program, or to annual physical examination only.  The mortality rate from breast cancer was the same in both groups, confirming no benefit to breast screening in healthy women.

The Canadian Task Force on Preventive Care notes that if 720 women between the ages of 50 to 69 were screened every two to three years over an 11 year period, 204 women would experience a false-positive result on a mammogram, 26 would have an unnecessary biopsy of their breast and one death from breast cancer would be prevented.  The Task Force reiterates that over-diagnosis can lead to additional imaging, biopsies, procedures, psychological distress and additional radiation exposure from mammograms.

HealthyDebate.ca’s article on decision aids includes a polka-dot graphic that illustrates some of the Canadian Task Force data.  This graphic draws attention to three different types of false-positive mammography results in women ages 40-49:  those who are only brought back for additional imaging (625 out of 2500 women); those who also undergo needle or surgical biopsy (75 out of 2500 women); and those who undergo unnecessary partial or full mastectomy (10 out of 2500 women).  The associated article emphasizes the need for healthcare providers to discuss benefits and harms associated, as well as the patient’s values and preferences, when considering treatment option.

Two pamphlets to inform patients who are debating mammograms are available online from The Public Health Agency of Canada and The Nordic Cochrane Centre.  And to help patients make sense of the numbers, this infographic and this article explain the difference between relative and absolute benefits of breast cancer screening.

Despite the weak data supporting mammography screening, in Ontario there are still financial incentives in place to enroll women in screening: Family doctors are eligible for a $2,000 bonus if they enroll 80% of their female patients aged 50 to 69 in a biannual mammography screening program.

CT scans and MRIs

CT or CAT scans produce cross-sectional images of the body using strong X-rays and a computer.  They are useful for things like assessing internal injuries or planning radiotherapy, but they can also highlight details that have no clinical significanceCT scans are routinely over-prescribed to asymptomatic patients, even though they are a significant source of ionizing radiation — which means they can increase patients’ risk of cancers in the future.

A study published in Radiology shows when 1,000 symptom-free people underwent full body CT scans, 86% had an abnormality detected.  The average person had 2.8 abnormalities or incidentalomas revealed by the CT scan — items which appeared unusual, but either disappeared on their own or were so slow-growing that they never went on to threaten the individual.

A spiral scan of the abdomen or pelvis exposes a patient to about 10 mSv of radiation.  The risk of one or two of these procedures is negligible. But in young patients, five of these tests exposes patients to the same amount of radiation that produced carcinogenic effects in the atom bomb survivors of Hiroshima and Nagasaki.

More than 80 million CT scans are performed in the U.S. every year, yet many doctors — including radiologists — have limited knowledge of the doses and of the potential consequences of diagnostic medical radiation exposure.  For example, just one CT scan can expose you to as much radiation as 200 chest X-rays.

Magnetic Resonance Imaging, or MRI, uses magnetic fields and radio wave energy to make detailed pictures of organs and tissues inside the body.  Most MRI requisitions come from family doctors and there are typically lengthy wait times for this procedure.  For example, according to the Canadian Institute for Health Information, patients in Alberta wait from 87-247 days for an MRI.  These wait times exist despite Alberta having the second highest number of scanners per capita in the country, suggesting that overuse may be a problem.

A recent study of MRI requests from Edmonton and Ottawa hospitals found that two thirds of MRI requests do not meet evidence-based guidelines for usage.  The same study found that  more than half of MRIs on low back pain patients were inappropriate or of questionable value. A 2013 study of MRI use in Alberta showed that over half of low back MRI scans in an Alberta hospital were not appropriate.  Research at the Acute Knee Injury Clinic in Calgary found almost two-thirds of the knee-injured patients who had an MRI could have been accurately diagnosed using other more readily available and significantly less expensive techniques and tools.

Knee injuries, low back pain and other common bone and joint conditions can be accurately diagnosed without expensive tests.  Training family physicians in diagnostic techniques for musculoskeletal conditions and having them apply MRI guidelines routinely could eliminate the majority of the inappropriate MRIs.  For instance, instead of an unnecessary MRI, a patient with lower back pain would receive a proper evaluation by a family physician, a discussion about the nature of back pain and the unlikelihood of a surgical option, and then other proactive approaches such as physiotherapy, exercise, acupuncture and/or medication.

One way to motivate health professionals to upgrade their training in these effective diagnostic techniques and patient counselling would be to introduce incentives for using evidence-based guidelines. In 2012, Canadians had 1.7 million MRIs — double the number in 2004. The savings could be huge given that Alberta data shows a lower back MRI costs the public health system approximately $1,000 while a knee MRI costs around $550.

Choosing Wisely Canada along with The Canadian Association of Radiologists has put together this list of five things a physician should question before ordering any imaging (e.g., CT scan, MRI).

Experts available for interview

Alan Cassels, CD, MPA
University of Victoria
Drug Policy, Ethics and Marketing
250-361-3120 | cassels@uvic.ca | @AKECassels

Irfan Dhalla, MD, MSc, FRCPC
University of Toronto
Organization/Financing of Health Care
416-864-6060 ext. 7113 | dhallai@smh.ca | @IrfanDhalla

Scottish Collaboration for Public Health Research and Policy, University of Edinburgh
UK Healthcare System, Health Inequalities, Prevention, and Public Health
011-44-131-651-1593 | john.frank@ed.ac.uk

David Henry, MBChB, MRCP, FRCP (Edin)
University of Toronto
Australian Healthcare System and What Drugs Should We Pay For and Why?
416-480-4297 | david.henry@ices.on.ca

James McCormack, PharmD
University of British Columbia
Appropriate/Rational Drug Therapy
604-603-7898 | jmccorma@interchange.ubc.ca | @medmyths

Kimberlyn McGrail, PhD

University of British Columbia
Variations, Aging, Outcomes
778-998-3821 | kmcgrail@chspr.ubc.ca

Thérèse Stukel, PhD
ICES/University of Toronto
Health Systems Research
416-480-6100 ext. 3928 | stukel@ices.on.ca

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