The effects of interventions on quality of life, morbidity and consultation frequency in frequent attenders in primary care: A systematic review.

BACKGROUND
Patients visiting their GPs exceptionally often (frequent attenders, FAs) have high rates of somatic disease, emotional distress, psychiatric illnesses and social problems and require a disproportionate amount of their GPs' time.


OBJECTIVES
To summarize which types of FA have been studied and what the effects of interventions were on quality of life (QoL), symptom severity of underlying illness(es) and consultation frequency. To discover when patients are considered FAs.


METHODS
Systematic review of RCTs using a comprehensive search (MEDLINE, PsycINFO, CINAHL and EMBASE, from 1980 to August 2015) and no language restrictions. Two investigators extracted data. Results were summarized qualitatively.


RESULTS
We included 17 RCTs. Heterogeneity at the level of populations, interventions and outcomes precluded statistical pooling. In-depth analysis by GPs assessing a patient's reasons for frequent attendance decreased consultation frequency by four to six per year. A small effect on symptom severity was noted in depressed FAs, although this finding was not replicated in a recent trial. Multi-component therapy and medication in FAs with medically unexplained symptoms (MUS) improved QoL (SF36 odds ratio: 1.92; 95%CI: 1.08-3.40) and morbidity (CES-D 3.17; 95%CI: 1.27-5.08).


CONCLUSION
RCTs on intervention effects in frequent attenders to primary care used different patient populations, interventions, comparators and outcome measures. Consistent evidence on the effects of particular interventions in specific patient domains is lacking. A tailored approach based on in-depth analysis among GPs of potential reasons for frequent attendance may decrease consultation frequency. Research involving the screening and treating for FAs with MUS may be useful in future trials.


Introduction
Since the 1960s, it has been observed that the general practitioner (GP) sees a proportion of his or her registered patients, frequently. [1][2][3] In particular, GPs spend almost 40% of their time on 10% of their patients. [4] Studies consistently report that the majority of these frequent attenders (FAs) have mental health problems, emotional distress and/or social difficulties, mostly on top of physical illness. [5,6] Chronic somatic and psychiatric illnesses are usually accepted reasons for frequent consultation. Temporary crises pass and may be a reason for brief periods of frequent consultation. Research shows that regression to the mean occurs, and only one out of seven patients remain FAs for three consecutive years. [4] However, frequent attendance by multi-problem patients with undetected psychiatric morbidity may trigger many consultations and lead to ineffective healthcare and persistent frequent attendance. [7] Persistent FAs ( 3 consecutive years of attendance ranking in the (sex-age adjusted) top 10%) make up about 1.6% of all enlisted patients, [4] implying that in The Netherlands an average GP has some 40 patients who consult very often over extended periods of time. GPs may perceive this as an important burden. Moreover, persistent frequent attendance is associated with major healthcare spending in primary and specialist healthcare. [8] If effective treatments exist, detection and treatment of morbidities could improve FAs' quality of life (QoL) and lower the impact of frequent attendance on the healthcare system. [4,9] Unfortunately, interpretation and comparison of studies on frequent attendance are difficult because of their heterogeneous characteristics and different definitions. [5] Smits et al., in 2008, systematically reviewed interventions on frequent attenders in primary care and found five randomized controlled trials (RCTs) describing interventions on FAs. [11] They found no convincing evidence that any intervention improves quality of life (QoL), morbidity or healthcare utilization of FAs. In the meantime, new RCTs have been published, and an updated review seems indicated. We wanted to answer the following questions: 1. Which interventions in FAs were studied in RCTs? 2. Which types of FAs were studied, and how were FAs defined? 3. What were the intervention effects on QoL, severity of symptoms or underlying illness(es) (morbidity) and consultation frequency?

Methods
We used acknowledged review methodology and reported according to PRISMA. [12] Eligibility criteria We accepted all definitions of the term 'frequent attender'. We defined primary care as all first points of consultation sites, not-in-hospital care. We included only RCTs. No language restrictions were used, and we accepted all possible interventions as long as a (usual care) control group was available.

Literature search
We

Quality assessment
One author (DH) appraised the quality of each RCT using a dedicated checklist. [13] This checklist consisted of nine methodological items scored as yes, no, or uncertain (Table 21). A second author (GtR) independently checked the quality assessments, which DH indicated as difficult to assess. Disagreements were resolved by consensus.

Selection of articles
The search yielded 1098 articles of which 17 were included. In an update of the search, an additional 253 articles were found, but no new eligible RCTs. Figure 1 shows a full flowchart.

Population and types of frequent attenders
The included studies targeted diverse types of FAs (Table 2). Three studies enrolled older FAs in health maintenance organizations (HMO) in the USA. [16,27,29] Three authors targeted depressed FAs. [17,18,26] One study targeted FAs with general mental health problems. [24] Six trials studied FAs with medically unexplained symptoms (MUS) or somatization. [19,[21][22][23][30][31] Three studies did not define a specific type of FAs. [20,25,28] One study used students attending a university health centre. [14] Another study targeted the so-called 'distressed FAs' (those with a sum score 1 standard deviation above population mean on the symptom checklist-revised). [15] Definitions of frequent attenders Definition of FA varied considerably. In particular, three studies used pre-set centiles of the attendance distribution. Thirteen used a cut-off number, ranging from 5-24 consultations per year (we normalized the number of consultations to a period of one year). Some authors chose this number based on the mean visit frequency for the (sub)group or clinic. One author used a 'healthcare utilization algorithm' to select FAs. [29] The time window, in which the consultation frequencies were assessed, also differed from three months to three years. [26,28] Interventions Table 2 shows a full list of interventions. Interventions varied considerably per subtype of FA and were listed by subtype of FAs.
Older FAs. Two out of three studies used a group intervention. Beck et al. used a group intervention led by a GP and a nurse consisting of health education, prevention measures such as house safety, exercise, nutrition, and mutual support. [16] Haas et al. compared health education classes to enhanced mental benefits, including psychiatric evaluation, psychotherapy visits, and if needed, medication. [27] Shannon et al. investigated referrals to home and community-based services (HCBS). [29] Depressed FAs. All three studies offered a depression management programme. Katzelnick and Simon refer to the same research programme. [17,18] They implemented a depression management programme, which consisted of a two-hour training, evaluation contacts, antidepressant medication, information material, and assignment of a treatment coordinator. In the third trial, Berghofer et al. assessed a depression management programme, consisting of a treatment algorithm, pharmacotherapy, standardized patient-provider education, and physician and patient counselling. [26] FAs with MUS or somatoform symptoms. Six studies targeted these FAs using patient or GP education, disclosures of events, acupuncture or cognitive therapy. Larisch targeted FAs with somatoform symptoms by offering six 20-min consultations with their GP over six months. [21] The GPs received 12-h training about treating somatization (role play, video feedback, using a reattribution model). Schilte et al. treated FAs using disclosure of emotionally important events by FAs in two or three meetings with a trained 'disclosure doctor'. [19] Patients received screening questions and kept a diary about their experiences. Rasmussen used an hour-long 'health enhancement consultation' by a nurse with the GP present. Medical records were reviewed by two GPs to assess whether hospitalization was avoidable. Smith et al. intervened by conducting 12 nurse practitionerled 20-min visits using multi-step patient-centred methods. [22] Treatment included antidepressants, reduction of ineffective medications, exercise, relaxation/physical therapy, and physical disease management. Telephone contact was scheduled between visits. Van Ravesteijn applied eight 2.5-h mindfulness sessions. [31] Patients received information about the sessions, homework assignments and forms to keep a record of their adherence, together with CDs with meditations and exercises. Paterson et al. applied 12 individual sessions (60 min, over a six-month period) of acupuncture by eight acupuncture practitioners. [30] Distressed FAs. In the only trial that focused on distressed FAs, a diagnostic Interview schedule and an interview was performed by a psychiatrist with the GP present after which a jointly formulated treatment plan was created for each FA [15]. Schreuders et al., in FAs with general mental health problems, tested a 'problem-solving treatment' (four to six 2.5-4 h sessions) by trained nurses, to increase the patients' understanding of the relationship between everyday problems and psychological symptoms. [24] No specific subtype of FAs. Four studies targeted all patients identified as FAs. Gidron et al. used a guided disclosure protocol. [28] Patients wrote (15 min for three days) about their most stressful experience of the past five years. Controls wrote about neutral topics. Christensen et al. used a patient questionnaire and an invitation for the FAs to contact their GP for a status consultation; information about the project; GP education on frequent attending; and economic incentives for the GP to perform the status consultation. [20] Bell on et al. applied a '7 hypothesis þ team intervention' after three GPs received 15-h training in the intervention. [25] The GPs held meetings to share analyses and reflections on their FAs and to make tailored plans for each FA. GPs also received emotional support in these meetings and helped generate strategies to deal with FAs. Finally, Olbrisch compared an educational programme aimed at making students aware of the psychological and social factors that make people prone to illness and inappropriate use of healthcare. It included a question and answer period and a demonstration of systematic deep muscle relaxation of which a relaxation tape or an individual session was offered. [14] Quality assessment Table 1 shows an overview of the quality assessment. Appendix 2 in Supplementary Material, available online, lists the full quality assessments in narrative form.

Study characteristics and effects per outcome
Heterogeneity at the level of patient populations, interventions and outcomes precluded sensible statistical pooling of results (See Table 2 for the characteristics per study.) Table 1. Quality assessment. Notes: The best possible score per study was (9 yes, 0 unclear, 0 no). (The scores can be found in the three columns on the far right). The bottom row lists the number of studies that met the criteria for each quality criterion.   More attendance (þ1.6 in the intervention group versus -2.0 in controls, (continued)

Quality of life
Eight studies measured QoL, of which four were of high quality (with concealed allocation, intention to treat analysis and overall high quality). Six studies used a generic short form scale. One study also used a visual analogue scale (VAS), two the EuroQol-5D. All studies targeted specific types of FAs. Two high-quality studies showed an effect on QoL. Smith et al. intervened by conducting visits using multi-step patientcentred methods including antidepressants, exercise, relaxation training, etc. They reported that the intervention group was more likely to improve (SF36) and the number needed to treat for one patient to improve was 6.4 (95%CI: 0.89-11.89). [23] Katzelnick et al. intervening in depressed FAs, reported a beneficial effect of depression management at 12 months on social functioning, mental health and general health perceptions (SF-20, P < 0.05 for all), but not on physical and role functioning and pain perception. [17] Participants in the mindfulness-based cognitive therapy (MBCT) group reported a greater improvement in mental functioning at the end of treatment (SF-6D: difference 3.9; 95%CI: 0.24-7.6), but between-group differences disappeared after nine months. [31] The general health status (EQ-5D VAS) did not differ at the end of treatment. The other studies have been summarized in Table 2.

Morbidity
We found 10 studies that assessed symptoms and (severity of) mental health diseases using various scales, of which four studies were of high quality. Four authors reported modest effects in three research programmes (Katzelnick and Simon referred to the same research programme [17,18]). They reported that patients in the intervention group had on average 47/365 more depression-free days following depression management (95%CI: 26.6-68.2), showed improvements of 9.2 versus 5.6 on the Hamilton score at 12 months for intervention and usual care patients, respectively (P < 0.001). Bergh€ ofer, in a more recent trial targeting depressed FAs, reported no differences on the HAMD-17 at six or 12 months. The intervention group had superior results after six months (56% reduction of the baseline B-PHQ-9 sum score versus 17% in controls; P < 0.002) but not at follow-up [26]. Smith et al. also reported less depressive symptomatology in the treatment group. [23] The calculated inter-group difference after one year was 1.44 (CES-D, 95%CI: -1.23-4.11) for treatment.

Frequency of attendance
Fifteen studies measured effects on the consultation frequency. Five RCTs were deemed to be of high quality. One RCT reported statistically significantly fewer primary care consultations. [25] Bell on et al. reported that the '7 hypothesis þ team (7H þ T) intervention' group (IG) consulted less compared to the two control groups (C1/C2) after one year. [25] Their intervention consisted of a group of GPs assessing the reasons why patients frequently attend. C1 received usual care by different GPs. C2 received usual care by the GPs that also intervened (IG-C1: -6.27, P ¼ 0.001; IG-C2: -3.62, P ¼ 0.006). Although Shannon et al., who intervened in older FAs, reported that the intervention group was more likely than controls to use GP services (odds ratio (OR): 2.05; P < 0.001), the number of hospital admissions (OR: 0.43; P < 0.01) and hospital days (OR: 0.39, P < 0.05) were more stable in the intervention group which was offered referrals and regular assessments. [29] Ravesteijn et al., who intervened in FAs with MUS using mindfulness-based cognitive therapy, found no difference between the consultation frequencies of both groups. [31] Simon and Katzelnick reported that the depression management programme, which targeted depressed FAs, resulted in more attendance in the intervention group (þ1.6 versus -2.0, P ¼ 0.02). [17,18] For the effects on consultation frequency on the other studies, see Table 2.

Strengths and limitations
To our knowledge, this systematic review is currently the most comprehensive review of interventions on FAs. We used acknowledged methodology and reported according to PRISMA. [12] We updated our previous systematic review using a more comprehensive search strategy developed by an experienced librarian (FvE) and found 13 additional trials. [11] This could be attributed to not using proximity keywords in a previous review by our team. The enormous variation in FA definition, patient selection methods across trials and settings, however, precluded drawing strong conclusions. A limitation of this review is that we took the effects reported at face value and did not go into detail about the various conceptual models underlying the interventions used. Furthermore, theoretically, randomization takes care of prognostic factors across intervention groups, however, without formally defining an a priori set of relevant prognostic factors implies that post-randomization baseline imbalances in prognostic factors could always be excluded. Although a review protocol existed, at the time it was not disseminated beyond our research group. Another possible limitation of the current review is that only two investigators screened the first 200 search results obtained independently. However, we felt that these 200 were sufficient for DH to become an expert. In addition, the articles that were selected for detailed reading (n ¼ 31) were assessed independently by two investigators against the inclusion criteria. The interrater reliability (Kappa) for this process was 0.718 (SEM: 0.131, 95%CI: 0.461-0.975), suggesting good agreement. In the update of the search, performed in August 2015, two independent investigators resulting in no discordances screened all new hits. Therefore, it is unlikely that we have missed many RCTs.

Comparison with existing literature
Based on a review in 2008 of five studies, Smits et al. concluded that 'no convincing treatment existed that was effective.' They noted a small effect in a subgroup of depressed patients in one trial. Recently, a trial looked at depressed patients but the (subgroup) effect reported by Katzelnick and Simon was not replicated. [26] The current review confirms the considerable heterogeneity at the level of patients, interventions, and outcome measures reported previously. [11] Implications for research and practice Most trials defined FAs using a cut-off based on an annual number of visits irrespective of sex, age and physician's work style. Selection that takes into account these factors is more appropriate and avoids the risk of over-representing elderly women. [5,10] Thus, only selecting the top centiles of the attenders, and stratifying for age and sex may allow for meaningful comparisons between countries, interventions, and their generalization. In their statistical analyses, trialists' should focus on between-group differences, not on differences between baseline and follow-up within groups. For instance, one study reported less depression in the treatment group (CES-D), but when we calculated the between-group difference, it was modest. [23] Also, applying a follow-up period of at least a year seems indicated, considering that frequent attending does not always persist. [4] Many FAs suffer from MUS and more research involving the selection of FAs and screening, and treating for MUS may be useful. More research is also needed to replicate and validate the modest results in the trials we found.
Concerning the high costs of FAs in primary and secondary care, intervention studies should preferably include a cost-effectiveness analysis. A programme as tested by Bell on [25] must be replicated in another RCT. The cost-effectiveness and cost-utility of this programme is currently being tested. [32]. Smith

Conclusion
Frequent attendance is a regular phenomenon in general practice and may be a burden to the GP, practice staff and work-flow. However, it does not seem to allow for a uniform approach or simple interventional procedures, but should perhaps be viewed as a trigger for stratification and differentiation according to individual patient's underlying conditions, adaptive selection and design of interventions, and professional staff's reflection on own attitudes and involvement. Indepth analysis among GPs assessing a particular patient's reasons for frequent attendance and corresponding tailored actions may decrease consultation frequency. An effect might also be present in FAs with MUS; however, more rigorously designed trials are needed to establish this.