University of Groningen The role of the general practitioner in the care for patients with colorectal cancer Brandenbarg, Daan

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The role of the general practitioner in the care for patients with colorectal cancer

Brandenbarg, Daan

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Brandenbarg, D. (2018). The role of the general practitioner in the care for patients with colorectal cancer.

Rijksuniversiteit Groningen.

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Due to the ageing of the population the number of people with cancer is expected to increase considerably in the foreseeable future, leading to an increased pressure on cancer care. This is also the case for colorectal cancer (CRC). As a result, optimal organization of care for patients with CRC is being debated. The Dutch cancer society (KWF kankerbestrijding) and the Dutch Society of General Practitioners (NHG) suggest substitution of follow-up care from secondary to primary care for the most prevalent cancer types, amongst which CRC. Practicing GPs, united in the National Union General Practitioners (Landelijke Huisartsenvereniging – LHV), resist because key conditions, such as time, support, and resources, should be met first.

The main goal of this thesis was to inform the debate about optimal care for patients with CRC. We presented data about the role of Dutch general practitioners (GPs) during all phases of care for CRC: role at time of diagnosis, provision of care during treatment and follow-up, and of care for long term health problems related to CRC. In this general discussion we will discuss the interpretations of our findings in the same order: the diagnostic trajectory, care during treatment, care during follow-up and long-term health care.

7.1 The diagnostic trajectory in primary care

GPs face the challenge to discriminate benign from malignant conditions in patients presenting with symptoms suggestive of CRC. The relatively low Dutch mortality figures compared to comparable countries such as the United Kingdom (1-3), might suggest that Dutch GPs appear to be doing well in this process. Given the expected increase in CRC incidence due to ageing of the population (4), an increased workload related to diagnostic management of patients with symptoms suggestive of CRC is to be expected. Whether the national screening program for CRC, implemented in 2014, attenuates this trend remains to be seen. Experiences from the UK suggest that the majority of patients is still being identified through symptomatic presentation in general practice (5-7). This, combined with the possibility of interval cancers occurring after a negative screening test, in patients outside the screening program or not partaking in it or its follow-up diagnostic tests, exemplifies the need for a thorough understanding of the diagnostic trajectory.

At the start of this PhD trajectory little was known about the diagnostic process for CRC in Dutch general practice, except for a comparison of diagnostic delays between the Netherlands and two other European countries. That study showed no significant difference in delay for a patient presenting in primary care and being referred to secondary care between the Netherlands, Sweden and Scotland (8). A recent Dutch study suggested that 10−25% of patients with cancer show substantially long diagnostic intervals, and delay appears to be especially long for CRC (9). However, when optimal care for patients with CRC is being debated, dominated by arguments concerning effectiveness in time and resources, it is important to further evaluate the current diagnostic process in Dutch general practice.

7.1.1 Rethinking alarm symptoms

The diagnostic work-up for the possibility of CRC is addressed in only one guideline for GPs; the Dutch guideline for rectal bleeding (10). In this guideline, rectal bleeding is considered as the most predictive alarm symptom for CRC. However, in a primary care setting this alarm symptom

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has been shown to have a positive predictive value of 2.4% (11). In other words, only 2.4% of patients presenting with this symptom is eventually diagnosed with CRC. This increases to 6.8% when reported twice in a two year period before diagnosis, and to 8.5% when combined with an abnormal finding on a rectal exam (11). Other alarm symptoms such as abdominal pain, constipation, diarrhea, or weight loss show even lower positive predictive values (12). If GPs would refer all patients with these symptoms to secondary care for diagnostic work-up, diagnostic facilities in secondary care would be overloaded, costs would increase drastically, and harm caused by diagnostic procedures would increase.

GPs are not merely guided by symptoms or warning signs when diagnosing illnesses. GPs also appear to respond to a “gut feeling”. This has been defined as “an uneasy feeling perceived by a GP when concerned about a possible adverse outcome, even though the specific indications are lacking” (13,14). A recent study showed that the positive predicted values for GPs having a gut feeling that there could be a malignancy was around 35%. The odds of a correct gut feeling increased with each year a GP knew the patient (15). This suggests that continuity of the relation between patient and GP is an important facilitator of the diagnostic process. It might enable a GP to pick up contextual cues suggestive of cancer. Changes in consultation patterns of patients, such as increased consultation frequencies for abdominal symptoms and general problems, might be one of these cues, and possibly more informative than guidance merely based on alarm symptoms.

7.1.2 Opportunities to improve the diagnostic process of CRC in Dutch

primary care

In this thesis (Chapter 2) we found that patients eventually diagnosed with CRC had a 41% higher consultation rate in the year prior to diagnosis compared to controls. These consultations were related to a variety of abdominal problems, not necessarily alarm symptoms, and a variety of more general complaints. This, combined with the expected increase in incidence of CRC, possibly leads to an increased workload for GPs in diagnosing CRC. We also observed (Chapter 2) that in the diagnostic trajectory of CRC in primary care there were possible diagnostic opportunities that were not employed. These opportunities for diagnostic improvement were related to patient and doctor factors. Both patient and doctor factors are in turn influenced by characteristics of the health care system in which they operate (16). It is therefore interesting to unravel the patient and doctor factors, and to theorize which characteristics of the health care system in the Netherlands might be of influence.

7.1.3 Diagnostic opportunities: patient factors and the health care

system

From our qualitative study it appeared that some patients seem to wait a long period before they presented bowel problems to their GP (Chapter 2). Non-recognition of serious symptoms, or the shameful nature of complaints has been identified as an explanation for this (17,18). Also, it has been shown that fear for what the doctor might find is a prominent barrier for help-seeking (18,19). Besides, a relationship exists between lower socio-economic status and longer patient delays

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(18,20). It might be that properties of our health care system influence these delays. However, this has to date not been thoroughly studied. Earlier research suggested that health care systems with a form of co-payment by the patient might deter patients from help seeking (21). In the Netherlands, co-payment in the form of a deductible was introduced for health insurances in 2008. A deductible is an annual amount of health care costs that has to be paid out of pocket by the patient. This compulsory deductible, intended to create cost awareness among the population, increased to €385.- in 2017, but could be voluntarily raised up to €885.- in exchange for a lower insurance premium. Whereas the GP consultations are excluded from the deductible, most follow-up diagnostic procedures in primary care and all costs in secondary care are not. In 2016, a survey among the Dutch general population was performed to assess the accessibility of care and the behavior of patients related to the deductible. In that survey, 19% of the participants indicated that they delayed or avoided health care because of expected costs, the GP was the most avoided health care professional (22). In our analyses we did not differentiate between patients diagnosed before and after the introduction of the deductible, its effect on help seeking and behavior and delayed diagnoses for cancer, especially amongst deprived socioeconomic groups, needs to be examined.

7.1.4 Diagnostic opportunities: GP factors and the health care system

In our qualitative analysis of electronic patient records, we observed that in certain cases (Chapter 2) the diagnostic process may have been expedited by doctor factors. We found that in these cases GPs appear to stick to preliminary diagnoses based on existing conditions, medication or co-morbidities, or explanations of patients or colleagues. It has been theorized that doctors typically use a variety of heuristics for efficiently arriving at decisions in the face of limited time or data (23,24). A heuristic is any approach to problem solving, learning, or discovery that employs a practical method not guaranteed to be optimal or perfect, but sufficient for the immediate goals. Where finding an optimal solution is impossible or impractical, a heuristic approach can be used to speed up the process of finding a satisfactory solution (25). A heuristic approach can also be a mental shortcut that eases the cognitive load of making a decision. Sticking to a preliminary diagnosis, and accepting explanations of patients or colleagues might be such a heuristic employed due to limited time.

Earlier research has suggested that time pressure, either real or perceived, may inhibit doctors to obtain thorough history or elicit all clinical signs when present (16,26). In the past decade, Dutch GPs have been shown to have a higher work load, spend more time on non-patient activities such as administration, compared to their colleagues in surrounding countries (27). Besides, their tasks and responsibilities have been broadened. As described before, the workload for diagnosis of CRC might well increase substantially in the near future, and could lead to an increased employment of heuristics by GPs and less thorough obtainment of clinical history and signs, and possibly more missed diagnostic opportunities.

Especially administrative tasks that do not have a direct contribution to providing care in the perception of GPs are perceived as burdensome. This is exemplified by the fact that 70% of all Dutch GPs signed the 2015 pamphlet of the action group ‘Het roer moet om’, which roughly

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translates into ‘change course’. This pamphlet states that a fair deal of workload and administrative tasks are the result of the introduction of market forces, and the demand of insurance companies for quality indicators, in the Dutch health care system in 2006 (28).

This administrative workload, and the quality indicators for insurance companies should be considered critically, and should be minimized. Then, GPs can focus their attention on their patients, which will enable them to obtain all clinical signs and to pick up subtle cues suggestive of CRC. In combination with a continuous relationship between patient and GP, this might further reduce the missed diagnostic opportunities, and hopefully lead to an earlier detection of CRC.

7.2 GPs’ role during and immediately after treatment

At the start of this PhD study it was believed that GPs played little or no role in the care for patients with CRC during or immediately after treatment, and that patients were out of sight once they had been referred for CRC diagnosis (29). This is contradicted by the finding in this thesis (Chapter 3) that patients have 54% more contacts with their GP in the year after referral for CRC compared to controls. GPs appear to play a significant role during and immediately after treatment for CRC in treating side effects of surgical or adjuvant treatment for CRC, and in providing psychological support. This is in accordance with our finding that almost all patients (Chapter 5) stated that their GP visited them after surgery, and that patients expected their GP to do so. Patients also seemed to expect their GP to clarify medical issues they have about their cancer or the treatment, and give lifestyle advice beneficial for their treatment. Due to the expected increase in CRC incidence GPs face more patients with CRC, having a higher health care use. This could further increase the work load for GPs, and calls for effective solutions.

7.2.1 The need for support of GPs during treatment for CRC

Previous research showed that GPs feel confident about certain aspects of cancer care during and immediately after treatment, especially with regard to pain management and psychosocial support (30). GPs appear to feel unprepared to manage certain aspects of cancer-specific care. This may be attributed to minimal formal training in cancer care, the lack of appropriate guidelines, insufficient contact with oncologists or insufficient experience (30).

Current national Dutch guidelines for CRC do not mention the role of the GP during treatment

(31). Considering the GP’s role in the treatment of side-effects and in lifestyle related concerns, guidance on these issues might be useful for GPs. Guidelines might be a way to achieve this. Formal training in dealing with side-effects of different oncological therapies is another possibility, as is improving communication with medical specialists.

7.2.2 Good communication across the primary-secondary care interface

Many specialists are involved in the treatment of CRC, such as surgeons, gastroenterologists, radiotherapists, oncologists, and secondary care nurse practitioners. Therefore, treatment decisions and patient situations are usually discussed at multidisciplinary meetings in hospital. Whereas it would be impossible for GPs to attend these meetings, current ICT solutions such

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as videoconferencing, might give GPs the possibilities to participate in these meetings. When this is not feasible, good reports from these meetings available for GPs will provide the GP with necessary information, about what treatment decisions have been made, and what side-effects are to be expected. This could enable GPs to provide the clarification about CRC and its treatment patients expect from their GPs, and properly treat side-effects.

7.3 GPs’ role during follow-up care for CRC

In 2011 the Dutch Cancer Society called for a complete reconsideration on how the care for cancer should be managed in the Netherlands, especially during follow-up (32). Routine follow-up currently takes place in hospitals, starts after treatment, and lasts for 5 years after completion of treatment. Follow-up care consists of planned visits and routine tests aimed at early detection of recurrences, care for physical, psychological and social effects of cancer, and the provision of information, guidance and advice on (self ) management and lifestyle (33). In order to ensure good quality, accessible, and affordable care in the future, it is suggested that GPs will be responsible for this care (32,34).

Our results suggest that the GP already plays a substantial role during follow-up care for patients curatively treated for CRC. Patients have more contact with their GP 2–6 years after diagnosis of CRC (Chapter 4). This appears to be quite similar in timing to most secondary based follow-up routines: frequently during the first years of follow-up and less frequent towards the end of follow-up (5 years after the end of treatment). Patients consult their GP for clarification of medical issues, advice, psychosocial support, and lifestyle support (Chapter 4 & 6). These findings could suggest that formal follow-up services, including detection of recurrences, could be incorporated in current GP care. GPs in the Netherlands have been given the responsibility for the care of other chronic diseases, such as diabetes, chronic pulmonary diseases, and cardiovascular risk management. One third of all cancer patients are already involved in a disease management program for a chronic disease (35). It could be argued that for CRC patients, who are generally older, substitution of structured follow-up care for some patients could be achieved. However, what this follow-up care should encompass remains topic of debate.

Current follow-up for CRC according to Dutch specialist guidelines consists of bi-annual liver echography or abdominal CT for the first 1–2 years, and annual thereafter until 5 years after treatment. Furthermore, every 3–6 months carcino-embryonic antigen (CEA) testing is performed during 5 years after treatment and, one year after treatment a colonoscopy is performed (31).

However, there is no agreement about the optimal protocols for CRC follow-up. According to a Cochrane review, intensive follow-up protocols did not have an effect on overall or CRC-specific survival of patient treated for CRC compared to minimal follow-up protocols (Hazard Ratio: 0.90, 95% confidence interval [0.78−1.02]) (36). It is important to note that minimal follow-up did encompass some form of testing such as consultations, scans or CEA-tests. Also, most studies included in that review were performed more than 10 years ago. Results of older studies should no longer be considered relevant to the discussion of appropriate follow-up, as they are limited by more recent advances in diagnostics and therapy (37). A recent trial, not included in the Cochrane

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review, showed a positive effect on the proportion of detected recurrences eligible for curative treatment of intensified CEA testing and stepped annual imaging based on the outcome of CEA (2 consecutive rises of CEA). The study showed no differences in overall or disease specific survival compared to standard follow-up care consisting of outpatient clinic visits, ultrasonography of the liver, and chest X-rays (37). This follow-up schedule would mean a reduction of imaging compared to current Dutch guidelines (38). If future follow-up will be more reliant on CEA testing and less on imaging, GPs could be given the responsibility for these protocols. However, the perspectives about this of the key players in this field – patients, GPs, and specialists – need to be assessed in order to ensure support for such a change in follow-up routines.

7.3.1 Substitution of follow-up care from patients’ perspective

As we showed in a review in chapter 5, survivors of all types of cancer tend to have high expectations of follow-up care in terms of providing reassurance (39-43). Survivors want their follow-up to consist of tests (blood tests, scans, x-rays, or even total body scans) because this provides reassurance that they are “clean” or that cancer is in remission (42,44,45). Interestingly, follow-up routines also induce stress and anxiety before new appointments and tests (45,46). Survivors of cancer show a preference for hospital based routines (Chapter 5), possibly related to the experienced need for tests. However, patients also report unmet needs in secondary follow-up care: they experience a lack of time of the professional involved, emotional sfollow-upport, and continuity of care in routine hospital follow-up (47).

Most of the research to date about patients’ preferences is derived from studies among breast cancer survivors. In this thesis (Chapter 6), we showed that CRC patients also seemed to prefer hospital-based follow-up care. It has to be noted that the patients included in most studies, including our own, were treated years ago and have become accustomed to their follow-up in specialty care. Patients in these regimes have built a relationship with their follow-up provider, possibly explaining their preference for hospital based follow-up.

Despite a preference for hospital-based follow-up, patients with CRC visit their GP frequently during this period (Chapter 4 & 6) for clarification of issues, advice, and psychosocial support. In some cases they even seem to want their GP to keep checking them after hospital follow-up has ended (Chapter 6). This suggests patients value their GP and assume their GP has the necessary skills available to clarify medical issues for them, and provide advice regarding CRC and lifestyle, even though they report that the GP is not knowledgeable enough to provide follow-up care. GPs could possibly play a role in educating patients about the added value of tests in follow-up routines and manage the expectations patients have about follow-up.

Results from studies comparing primary care follow-up for patients with breast cancer and CRC to specialty care showed no differences in quality of life, patient satisfaction and clinical outcomes suggesting that patients are satisfied with GP-led follow-up (48,49). Therefore, it might be advisable to introduce substitution of care for newly treated patients.

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128 7.3.2 Substitution of follow-up care from GPs’ perspective

Although we did not study the perspective of GPs on substitution of follow-up in this thesis, it is important to know if GPs support this. As mentioned before, there appears to be a lack of consensus among GPs and their representative organizations, and many GPs have shown not to want GP-led follow-up (50). Reasons for this are lack of medical support, a perceived lack of knowledge, and a heavy workload (30,34).

Another issue for GPs concerning substitution of follow-up is proper remuneration (51,52). It has been calculated that GPs need extra consultation time of 19 hours per 1000 patients per year

(35), which could well be an underestimation considering the expected rise in diagnostic activity due to the increasing incidence of CRC.

7.3.3 Substitution of follow-up care from medical specialists’ perspective

We did not study the perspective of medical specialists on substitution of follow-up either in this thesis. However, it is important to note that these need to be taken into account as well. Medical specialists providing follow-up care do not favor substitution of (colorectal) cancer follow-up to primary care (50,53,54). Interestingly, more colorectal surgeons than GPs value GP-led follow-up positively, and express trust in the skills of GPs to identify and treat cancer related physical, psychological and social problems (50). But generally, a perceived lack of oncological knowledge and necessary diagnostic tools in primary care including the lack of skills to interpret results, are reported. However, the evidence for current intensive follow-up protocols in terms of survival benefit is limited (55). Also, adherence to follow-up guidelines in the Netherlands appears to vary widely (56), which is also suggested by varying hospital claims at insurance companies for follow-up controls of cancer (57). It might be possible that other motives to resist substitution are in place, such as fear for loss of income. As was mentioned earlier, since market forces are introduced in the Dutch health care system a commercial logic is required from hospitals in negotiating with and claiming reimbursements for treatments from insurance companies.

7.3.4 Substitution of follow-up for CRC: concluding

GPs already appear to provide certain aspects of cancer follow-up care, such as care for physical, psychological and social effects of cancer, and the provision of information, guidance and advice on (self ) management and lifestyle. It might be possible for GPs to coordinate planned visits and routine tests aimed at early detection of recurrences, especially if future follow-up consists mainly of CEA-measurements. This could fulfill patients’ desires for testing, while it provides the GP the opportunity to provide continuous and general care for their patients, monitor late effects, and discuss the value of tests and the anxious feelings resulting from these tests. If GPs are to be formally involved in all phases of care for patients with CRC, good communication between primary and secondary care is ensured, and evidence-based protocols for effective GP-led follow-up are developed, this substitution might be even more feasible.

Future research should examine whether it is acceptable for patients, GPs, and specialists that GPs provide future follow-up care. It is also important to know for which patients follow-up might be substituted, what follow-up protocols are feasible in general practice including specific

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roles for primary care nurses and GPs, and what remuneration has to be achieved for these extra consultations and personnel (e.g. practice nurses) for this task.

7.4 Care for late effects of CRC

Evidence about effective primary care interventions is limited for some aspects of cancer care provided by GPs. This concerns mainly lifestyle related issues and late effects such as fatigue. Fatigue is a very invalidating problem with a severe impact on quality of life among cancer survivors and it can be persistent for years after treatment (58). It can be expected that fatigued cancer survivors ask their General practitioner for advice to reduce their fatigue levels. In our qualitative analysis (Chapter 6), patients expressed that they consulted their GP for these issues, and that they expect lifestyle advices from the GP. Physical activity is one of the lifestyle interventions that has been linked to all sorts of favorable health outcomes, and is now being promoted in international guidelines for cancer survivors (59). However, whether physical activity is beneficial for the reduction of fatigue in survivors of CRC has never been examined. As we have shown in a systematic review (Chapter 7), the evidence that physical activity reduces fatigue levels in CRC survivors is lacking. However, no studies have been performed on actually fatigued survivors of CRC. This shows there is a great need for evidence about lifestyle advices and interventions that can be used in primary care.

Conclusion

In this thesis we have provided data on the current role of the GP in care for patients with CRC, aimed at informing the debate about the organization of cancer care in the Netherlands. GPs play a role in diagnosing CRC, which is likely to become more frequent with the rising of CRC incidence. Possible missed diagnostic opportunities arise because of late presentation of bowel problems by patients or because GPs appear to stick to preliminary diagnoses based on existing conditions, medication or co-morbidities, or explanations of patients or colleagues. Whereas thought otherwise, the GP also appears to stay involved in care during treatment for CRC. Patients have contact with their GP for problems related to their treatment, for (lifestyle) support, and psychosocial issues. Support for GPs in the form of guidelines, training, and good communication with secondary care, could further strengthen GPs’ role in this care. During follow-up for CRC GPs provide care for their patients with CRC, and if follow-up routines become less reliant on imaging techniques, there might be a possibility for substitution of follow-up controls from secondary care to primary care. However, there is a need for evidence on effective follow-up protocols in primary care, and obstacles in organization, and remuneration need to be overcome. Also, patient’s acceptance of primary care led follow-up has to be established, since most patients with (colorectal) cancer favor current hospital follow-up, and expect frequent tests for reassurance that their cancer is not recurring. Good evidence on effective strategies to treat long term problems such as fatigue is also necessary for use in primary care.

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