Family physician awareness of Charles Bonnet syndrome

Family physician awareness of Charles Bonnet syndrome Abstract Background Charles Bonnet syndrome is characterized by formed visual hallucinations in individuals with vision loss. It is reported that one in five older adults with vision loss suffer from Charles Bonnet syndrome and the suspected lack of awareness amongst family physicians may lead to misdiagnosis and inappropriate treatment. Objective To assess Canadian family physicians’ awareness of Charles Bonnet syndrome. Methods We conducted a national perception and practices survey of family physicians across Canada to assess (i) the level of awareness of Charles Bonnet syndrome amongst family physicians; (ii) the frequency of family physicians’ encounters with patients with visual hallucinations and (iii) management strategies and referral patterns for patients with Charles Bonnet syndrome presenting to family physicians. Results Four hundred and ninety-nine family physicians across Canada answered at least one question on the survey. 54.7% indicated they were not at all aware and 19.7% indicated they were slightly aware of Charles Bonnet syndrome. 72.8% of physicians had patients present with visual hallucinations once a year or less often. The frequency of patients seen in practice with visual hallucinations is significantly associated with awareness by physicians of Charles Bonnet syndrome (β = 0.501, t(388) = 5.59, P < 0.001). Of those who encountered patients with visual hallucinations, the majority of respondents (77.4%) provided counselling or education to the patient. Conclusion There is a great lack of knowledge about Charles Bonnet syndrome among family physicians. Awareness of Charles Bonnet syndrome is critical to appropriate diagnosis, assessment and treatment of this condition and to reassure patients that they are not suffering from a mental disorder. Charles Bonnet syndrome, national survey, vision loss, visual hallucinations Introduction The experience of formed visual hallucinations in people with vision loss and no psychological disorder was first observed and described by Charles Bonnet in 1760 (1). More than 250 years have elapsed and awareness of this condition, now called Charles Bonnet syndrome, is still woefully low even though the prevalence is quite high. A recent Canadian study showed that approximately one in five of 2550 people with vision loss attending a low-vision clinic for the first time had experienced visual hallucinations (2). This study also showed that the prevalence of visual hallucinations in Canada was essentially the same irrespective of the eye disease that caused the vision loss and was greater for people with greater levels of impairment. The hallucinations experienced by people with Charles Bonnet syndrome have been described as images that include ‘people (whole figures, faces, groups and miniature people), animals, trees and plants, scenes and a wide range of inanimate objects’ (3). They can also consist of patterns. Most individuals experiencing Charles Bonnet syndrome hallucinations are aware that they are not real (4–6). Differential diagnosis of Charles Bonnet syndrome requires ruling out other causes of visual hallucinations such as Parkinson’s disease and Lewy body dementia. This diagnosis may be made by a family physician, neurologist or psychiatrist, depending on the nature of the symptoms (7). Typical hallucinations are generally of short duration, lasting only minutes or seconds in most cases (8). A study by Cox and ffytche (8) reported that the frequency with which Charles Bonnet syndrome hallucinations occur varies greatly, with a small number of people (13%) experiencing hallucinations constantly. Most people experienced hallucinations weekly or monthly. Previous longitudinal studies have suggested that Charles Bonnet syndrome persists from a year to 18 months (9,10); however, 75% of the 492 people with Charles Bonnet syndrome in the Cox and ffytche study had had the condition for 5 years or more. These researchers also reported that only 36% of people who sought medical advice were given a clear explanation of the condition and that people who had received high-quality information about Charles Bonnet syndrome were less likely to have had a negative impact on their quality of life. Another study reported that only 9% of people with Charles Bonnet syndrome sought medical advice and, of those who did, only half received information about Charles Bonnet syndrome (4). Despite the longstanding history of Charles Bonnet syndrome and its increasing prevalence among the aging population, there are reports that the syndrome may be misdiagnosed or inappropriately treated (7,11). This situation is further complicated by patients’ reluctance to disclose their symptoms for fear of their being labelled mentally ill (6). Hallucinatory experiences can be disturbing and may serve as a source of anxiety and social isolation for patients (12). While patients may experience fear and depression as a result of their hallucinations, they generally feel reassured when they speak to a health care practitioner who is knowledgeable about Charles Bonnet syndrome (13). Many patients can tolerate living with their hallucinations as long as they are reassured of their relatively benign nature and that they are not ‘losing their minds’. Managing patients with Charles Bonnet syndrome involves optimizing patients’ vision and properly educating patients and their families about Charles Bonnet syndrome (13–15), particularly with respect to the benign nature of the condition and the fact that it is not related to mental illness. Medical treatment of Charles Bonnet syndrome has only met with limited success (14,15) with very few cases having been reported who responded to a wide variety of atypical antipsychotic medications such as risperidone, quetiapine and olanzapine. Anticonvulsants such as carbamazepine, clonazepam, valproate and gabapentin have also been used with varying success in a few cases. The current study was designed to help understand the level of knowledge of Charles Bonnet syndrome among family physicians and how they currently treat or refer patients with Charles Bonnet syndrome. It was hoped that the data generated from this study would be useful in raising the awareness of Charles Bonnet syndrome among medical practitioners, patients and the general public. Methods The survey questions shown in Table 1 were faxed to 4856 random family physicians across Canada. Randomization was achieved by surveying every fifth family physician in each province. All surveys conducted in Quebec were in French. Surveys in all other provinces were in English. For a confidence interval of 5% and a 95% confidence level, a minimum response of 7.8% (380 surveys) was required. Descriptive statistics were used to report general findings, as well as linear regression analysis and Student’s t-test for more detailed analysis. Statistical analysis was performed using SPSS statistical software (SPSS Inc.). A P-value of <0.05 was considered to be statistically significant. Table 1. Family physician survey questions Question Number of respondents Before receiving this survey, how would you describe your level of awareness of the visual hallucination condition called Charles Bonnet syndrome? 477 If you had heard of Charles Bonnet syndrome, where had you acquired this information? (Check all that apply.) 207 In your practice, how often have you had patients present with some type of visual hallucination? 408 When you encountered a patient with visual hallucinations, what did you do? (Check all that apply.) 299 When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? 403 Question Number of respondents Before receiving this survey, how would you describe your level of awareness of the visual hallucination condition called Charles Bonnet syndrome? 477 If you had heard of Charles Bonnet syndrome, where had you acquired this information? (Check all that apply.) 207 In your practice, how often have you had patients present with some type of visual hallucination? 408 When you encountered a patient with visual hallucinations, what did you do? (Check all that apply.) 299 When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? 403 View Large Table 1. Family physician survey questions Question Number of respondents Before receiving this survey, how would you describe your level of awareness of the visual hallucination condition called Charles Bonnet syndrome? 477 If you had heard of Charles Bonnet syndrome, where had you acquired this information? (Check all that apply.) 207 In your practice, how often have you had patients present with some type of visual hallucination? 408 When you encountered a patient with visual hallucinations, what did you do? (Check all that apply.) 299 When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? 403 Question Number of respondents Before receiving this survey, how would you describe your level of awareness of the visual hallucination condition called Charles Bonnet syndrome? 477 If you had heard of Charles Bonnet syndrome, where had you acquired this information? (Check all that apply.) 207 In your practice, how often have you had patients present with some type of visual hallucination? 408 When you encountered a patient with visual hallucinations, what did you do? (Check all that apply.) 299 When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? 403 View Large The study was approved by the Research Ethics Board of the University of Toronto. Results A total of 499 respondents to the survey answered at least one question in the survey. The results showed that the level of awareness of Charles Bonnet syndrome among family physicians was extremely low, 54.7% of family physician respondents indicating they were not at all aware and 19.7% indicating they were only slightly aware. Of the 207 respondents who were aware of Charles Bonnet syndrome, about a quarter (27.5%) said they had heard about it in their medical training; 18.4% from a colleague or consult; 16% from a conference or through continuing medical education and 14.3% from a patient. Most respondents (72.8%) had patients present with visual hallucinations once a year or less often (Figure 1). Most respondents (77.4%) who encountered patients with visual hallucinations, provided counselling or education to the patient. 33.1% of respondents referred the patient with visual hallucinations to a psychiatrist; 27.4% to an ophthalmologist; and 16.1% to a neurologist (Figure 2). Almost all respondents never discuss the possibility of Charles Bonnet syndrome with a patient who presents with severe vision loss (Figure 3). Figure 1. View largeDownload slide In your practice, how often have you had patients present with some type of visual hallucination? (n = 408) Figure 1. View largeDownload slide In your practice, how often have you had patients present with some type of visual hallucination? (n = 408) Figure 2. View largeDownload slide When you encountered a patient with visual hallucinations, what did you do? (Check all that apply). (n = 299) Figure 2. View largeDownload slide When you encountered a patient with visual hallucinations, what did you do? (Check all that apply). (n = 299) Figure 3. View largeDownload slide When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? (n = 403) Figure 3. View largeDownload slide When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? (n = 403) The last question in the survey asked respondents if they had anything more they would like to say about this issue; 146 people responded to this question. The general themes that emerged from these responses were that respondents were pleased to receive this survey as it helped educate them about Charles Bonnet syndrome and that there was a need for more education about Charles Bonnet syndrome. Regression analysis demonstrated that frequency of patients seen in practice with visual hallucinations is significantly associated with awareness by physicians of Charles Bonnet syndrome (β = 0.501, t(388) = 5.59, P < 0.001). Family physicians who provided counselling and education for patients had a significantly higher frequency of patients with visual hallucinations in their practice (P = 0.012, P < 0.001). Family physicians who referred their patients to geriatricians also saw patients with visual hallucinations in their practice more frequently (P = 0.04). No other significant associations were noted. Study limitations While a faxed survey has the advantage of a better response rate, it does bring into question whether the list of doctors with fax machines is truly representative of the total population. Since the survey background explains what Charles Bonnet syndrome is, this may elicit a higher response from respondents saying they were aware of the condition as their memory has been stimulated by the introduction. The survey did not probe to see how long doctors had been in practice, so it was not possible to determine if doctors had been taught about Charles Bonnet syndrome and had forgotten over time. Doctors did not access their records to determine how often they saw patients with visual hallucinations. For this reason, responses to this question must be interpreted as indicative of a practice pattern only. Conclusion The results indicate that there is a great lack of knowledge about Charles Bonnet syndrome among family physicians with more than half of respondents never having heard of this condition even though it is relatively common in that it affects around one in five people who have experienced vision loss. Of those who had heard of Charles Bonnet syndrome, only one in four had heard of the condition in their medical training. The lack of education about Charles Bonnet syndrome was further reflected in the open-ended question in which many respondents suggested that there was a need for more education about Charles Bonnet syndrome. Part of the challenge is that about three quarters of individual physicians saw patients with visual hallucinations once a year or less often. We tested whether awareness was greater among respondents who saw patients with visual hallucinations more often and found that the frequency with which a respondent saw patients with visual hallucinations was significantly associated with awareness by physicians of Charles Bonnet syndrome. Of the respondents who saw patients with visual hallucinations, most provided counselling or education. The frequency with which family physicians saw patients with visual hallucinations in their practice was associated with their likelihood of providing education and counselling. As discussed previously, education and counselling are the mainstays of treatment of Charles Bonnet syndrome. It is important that family physicians be aware of Charles Bonnet syndrome, to provide the appropriate counselling for patients with vision loss experiencing visual hallucinations. About a third of respondents in this study referred patients to a psychiatrist, a quarter to an ophthalmologist and about one in six to a neurologist. Referrals to geriatricians were also more likely to be made by family physicians who saw patients with visual hallucinations more frequently. Although Charles Bonnet syndrome itself is relatively benign, it is important that a differential diagnosis be made to rule out other causes of hallucinations. Almost all respondents never discussed Charles Bonnet syndrome as a possibility with patients who have experienced severe vision loss. Considering that many patients are reluctant to tell their doctors that they are experiencing hallucinations, it is important that family physicians are prepared to discuss this possibility with patients who may experience Charles Bonnet syndrome. Family physicians can play a significant role in helping patients who experience visual hallucinations overcome their fear of this condition by reassuring them that many patients who have lost significant vision experience hallucinations and that there is no connection to a mental disorder. Family physicians may also refer patients with visual hallucinations to the appropriate specialist, to rule out any other cause of visual hallucinations. It is hoped that increasing awareness of Charles Bonnet syndrome among family physicians will help increase awareness of the condition among patients and their families so that very few people have to feel that they are ‘going crazy’ when they experience these hallucinations. Declaration Funding: This study has been supported by an educational grant from Bayer Canada. Ethical approval: Research ethics board (REB) approval was granted through the University of Toronto. Conflict of interest: The authors have no conflicts of interest to declare. References 1. Bonnet C. Essai Analytique Sur Les Facultés De L’Ame: 6; Copenhague . 1760 . 2. Gordon KD . Prevalence of visual hallucinations in a national low vision client population . Can J Ophthalmol 2016 ; 51 : 3 – 6 . Google Scholar Crossref Search ADS PubMed 3. Wilkinson F . Auras and other hallucinations: windows on the visual brain . Prog Brain Res 2004 ; 144 : 305 – 20 . Google Scholar Crossref Search ADS PubMed 4. Gilmour G , Schreiber C , Ewing C . An examination of the relationship between low vision and Charles Bonnet syndrome . Can J Ophthalmol 2009 ; 44 : 49 – 52 . Google Scholar Crossref Search ADS PubMed 5. Schultz G , Melzack R . The Charles Bonnet syndrome: ‘phantom visual images’ . Perception 1991 ; 20 : 809 – 25 . Google Scholar Crossref Search ADS PubMed 6. Teunisse RJ , Cruysberg JR , Hoefnagels WH , Verbeek AL , Zitman FG . Visual hallucinations in psychologically normal people: Charles Bonnet’s syndrome . Lancet 1996 ; 347 : 794 – 7 . Google Scholar Crossref Search ADS PubMed 7. Menon GJ , Rahman I , Menon SJ , Dutton GN . Complex visual hallucinations in the visually impaired: the Charles Bonnet syndrome . Surv Ophthalmol 2003 ; 48 : 58 – 72 . Google Scholar Crossref Search ADS PubMed 8. Cox TM , ffytche DH . Negative outcome Charles Bonnet syndrome . Br J Ophthalmol 2014 ; 98 : 1236 – 9 . Google Scholar Crossref Search ADS PubMed 9. Jackson ML , Bassett KL . The natural history of the Charles Bonnet syndrome. Do the hallucinations go away ? Eye (Lond) 2010 ; 24 : 1303 – 4 . Google Scholar Crossref Search ADS PubMed 10. Holroyd S , Rabins PV . A three-year follow-up study of visual hallucinations in patients with macular degeneration . J Nerv Ment Dis 1996 ; 184 : 188 – 9 . Google Scholar Crossref Search ADS PubMed 11. Jan T , Del Castillo J . Visual hallucinations: Charles Bonnet syndrome . West J Emerg Med 2012 ; 13 : 544 – 7 . Google Scholar Crossref Search ADS PubMed 12. Vukicevic M , Fitzmaurice K . Butterflies and black lacy patterns: the prevalence and characteristics of Charles Bonnet hallucinations in an Australian population . Clin Exp Ophthalmol 2008 ; 36 : 659 – 65 . Google Scholar Crossref Search ADS PubMed 13. Nguyen ND , Osterweil D , Hoffman J . Charles Bonnet syndrome: treating nonpsychiatric hallucinations . Consult Pharm 2013 ; 28 : 184 – 8 . Google Scholar Crossref Search ADS PubMed 14. Eperjesi F , Akbarali N . Rehabilitation in Charles Bonnet syndrome: a review of treatment options . Clin Exp Optom 2004 ; 87 : 149 – 52 . Google Scholar Crossref Search ADS PubMed 15. Pang L . Hallucinations experienced by visually impaired: Charles Bonnet syndrome . Optom Vis Sci 2016 ; 93 : 1466 – 78 . Google Scholar Crossref Search ADS PubMed © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model) http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Family Practice Oxford University Press

Family physician awareness of Charles Bonnet syndrome

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Abstract

Abstract Background Charles Bonnet syndrome is characterized by formed visual hallucinations in individuals with vision loss. It is reported that one in five older adults with vision loss suffer from Charles Bonnet syndrome and the suspected lack of awareness amongst family physicians may lead to misdiagnosis and inappropriate treatment. Objective To assess Canadian family physicians’ awareness of Charles Bonnet syndrome. Methods We conducted a national perception and practices survey of family physicians across Canada to assess (i) the level of awareness of Charles Bonnet syndrome amongst family physicians; (ii) the frequency of family physicians’ encounters with patients with visual hallucinations and (iii) management strategies and referral patterns for patients with Charles Bonnet syndrome presenting to family physicians. Results Four hundred and ninety-nine family physicians across Canada answered at least one question on the survey. 54.7% indicated they were not at all aware and 19.7% indicated they were slightly aware of Charles Bonnet syndrome. 72.8% of physicians had patients present with visual hallucinations once a year or less often. The frequency of patients seen in practice with visual hallucinations is significantly associated with awareness by physicians of Charles Bonnet syndrome (β = 0.501, t(388) = 5.59, P < 0.001). Of those who encountered patients with visual hallucinations, the majority of respondents (77.4%) provided counselling or education to the patient. Conclusion There is a great lack of knowledge about Charles Bonnet syndrome among family physicians. Awareness of Charles Bonnet syndrome is critical to appropriate diagnosis, assessment and treatment of this condition and to reassure patients that they are not suffering from a mental disorder. Charles Bonnet syndrome, national survey, vision loss, visual hallucinations Introduction The experience of formed visual hallucinations in people with vision loss and no psychological disorder was first observed and described by Charles Bonnet in 1760 (1). More than 250 years have elapsed and awareness of this condition, now called Charles Bonnet syndrome, is still woefully low even though the prevalence is quite high. A recent Canadian study showed that approximately one in five of 2550 people with vision loss attending a low-vision clinic for the first time had experienced visual hallucinations (2). This study also showed that the prevalence of visual hallucinations in Canada was essentially the same irrespective of the eye disease that caused the vision loss and was greater for people with greater levels of impairment. The hallucinations experienced by people with Charles Bonnet syndrome have been described as images that include ‘people (whole figures, faces, groups and miniature people), animals, trees and plants, scenes and a wide range of inanimate objects’ (3). They can also consist of patterns. Most individuals experiencing Charles Bonnet syndrome hallucinations are aware that they are not real (4–6). Differential diagnosis of Charles Bonnet syndrome requires ruling out other causes of visual hallucinations such as Parkinson’s disease and Lewy body dementia. This diagnosis may be made by a family physician, neurologist or psychiatrist, depending on the nature of the symptoms (7). Typical hallucinations are generally of short duration, lasting only minutes or seconds in most cases (8). A study by Cox and ffytche (8) reported that the frequency with which Charles Bonnet syndrome hallucinations occur varies greatly, with a small number of people (13%) experiencing hallucinations constantly. Most people experienced hallucinations weekly or monthly. Previous longitudinal studies have suggested that Charles Bonnet syndrome persists from a year to 18 months (9,10); however, 75% of the 492 people with Charles Bonnet syndrome in the Cox and ffytche study had had the condition for 5 years or more. These researchers also reported that only 36% of people who sought medical advice were given a clear explanation of the condition and that people who had received high-quality information about Charles Bonnet syndrome were less likely to have had a negative impact on their quality of life. Another study reported that only 9% of people with Charles Bonnet syndrome sought medical advice and, of those who did, only half received information about Charles Bonnet syndrome (4). Despite the longstanding history of Charles Bonnet syndrome and its increasing prevalence among the aging population, there are reports that the syndrome may be misdiagnosed or inappropriately treated (7,11). This situation is further complicated by patients’ reluctance to disclose their symptoms for fear of their being labelled mentally ill (6). Hallucinatory experiences can be disturbing and may serve as a source of anxiety and social isolation for patients (12). While patients may experience fear and depression as a result of their hallucinations, they generally feel reassured when they speak to a health care practitioner who is knowledgeable about Charles Bonnet syndrome (13). Many patients can tolerate living with their hallucinations as long as they are reassured of their relatively benign nature and that they are not ‘losing their minds’. Managing patients with Charles Bonnet syndrome involves optimizing patients’ vision and properly educating patients and their families about Charles Bonnet syndrome (13–15), particularly with respect to the benign nature of the condition and the fact that it is not related to mental illness. Medical treatment of Charles Bonnet syndrome has only met with limited success (14,15) with very few cases having been reported who responded to a wide variety of atypical antipsychotic medications such as risperidone, quetiapine and olanzapine. Anticonvulsants such as carbamazepine, clonazepam, valproate and gabapentin have also been used with varying success in a few cases. The current study was designed to help understand the level of knowledge of Charles Bonnet syndrome among family physicians and how they currently treat or refer patients with Charles Bonnet syndrome. It was hoped that the data generated from this study would be useful in raising the awareness of Charles Bonnet syndrome among medical practitioners, patients and the general public. Methods The survey questions shown in Table 1 were faxed to 4856 random family physicians across Canada. Randomization was achieved by surveying every fifth family physician in each province. All surveys conducted in Quebec were in French. Surveys in all other provinces were in English. For a confidence interval of 5% and a 95% confidence level, a minimum response of 7.8% (380 surveys) was required. Descriptive statistics were used to report general findings, as well as linear regression analysis and Student’s t-test for more detailed analysis. Statistical analysis was performed using SPSS statistical software (SPSS Inc.). A P-value of <0.05 was considered to be statistically significant. Table 1. Family physician survey questions Question Number of respondents Before receiving this survey, how would you describe your level of awareness of the visual hallucination condition called Charles Bonnet syndrome? 477 If you had heard of Charles Bonnet syndrome, where had you acquired this information? (Check all that apply.) 207 In your practice, how often have you had patients present with some type of visual hallucination? 408 When you encountered a patient with visual hallucinations, what did you do? (Check all that apply.) 299 When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? 403 Question Number of respondents Before receiving this survey, how would you describe your level of awareness of the visual hallucination condition called Charles Bonnet syndrome? 477 If you had heard of Charles Bonnet syndrome, where had you acquired this information? (Check all that apply.) 207 In your practice, how often have you had patients present with some type of visual hallucination? 408 When you encountered a patient with visual hallucinations, what did you do? (Check all that apply.) 299 When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? 403 View Large Table 1. Family physician survey questions Question Number of respondents Before receiving this survey, how would you describe your level of awareness of the visual hallucination condition called Charles Bonnet syndrome? 477 If you had heard of Charles Bonnet syndrome, where had you acquired this information? (Check all that apply.) 207 In your practice, how often have you had patients present with some type of visual hallucination? 408 When you encountered a patient with visual hallucinations, what did you do? (Check all that apply.) 299 When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? 403 Question Number of respondents Before receiving this survey, how would you describe your level of awareness of the visual hallucination condition called Charles Bonnet syndrome? 477 If you had heard of Charles Bonnet syndrome, where had you acquired this information? (Check all that apply.) 207 In your practice, how often have you had patients present with some type of visual hallucination? 408 When you encountered a patient with visual hallucinations, what did you do? (Check all that apply.) 299 When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? 403 View Large The study was approved by the Research Ethics Board of the University of Toronto. Results A total of 499 respondents to the survey answered at least one question in the survey. The results showed that the level of awareness of Charles Bonnet syndrome among family physicians was extremely low, 54.7% of family physician respondents indicating they were not at all aware and 19.7% indicating they were only slightly aware. Of the 207 respondents who were aware of Charles Bonnet syndrome, about a quarter (27.5%) said they had heard about it in their medical training; 18.4% from a colleague or consult; 16% from a conference or through continuing medical education and 14.3% from a patient. Most respondents (72.8%) had patients present with visual hallucinations once a year or less often (Figure 1). Most respondents (77.4%) who encountered patients with visual hallucinations, provided counselling or education to the patient. 33.1% of respondents referred the patient with visual hallucinations to a psychiatrist; 27.4% to an ophthalmologist; and 16.1% to a neurologist (Figure 2). Almost all respondents never discuss the possibility of Charles Bonnet syndrome with a patient who presents with severe vision loss (Figure 3). Figure 1. View largeDownload slide In your practice, how often have you had patients present with some type of visual hallucination? (n = 408) Figure 1. View largeDownload slide In your practice, how often have you had patients present with some type of visual hallucination? (n = 408) Figure 2. View largeDownload slide When you encountered a patient with visual hallucinations, what did you do? (Check all that apply). (n = 299) Figure 2. View largeDownload slide When you encountered a patient with visual hallucinations, what did you do? (Check all that apply). (n = 299) Figure 3. View largeDownload slide When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? (n = 403) Figure 3. View largeDownload slide When speaking with a patient with severe vision loss, do you discuss the possibility of the patient developing Charles Bonnet hallucinations? (n = 403) The last question in the survey asked respondents if they had anything more they would like to say about this issue; 146 people responded to this question. The general themes that emerged from these responses were that respondents were pleased to receive this survey as it helped educate them about Charles Bonnet syndrome and that there was a need for more education about Charles Bonnet syndrome. Regression analysis demonstrated that frequency of patients seen in practice with visual hallucinations is significantly associated with awareness by physicians of Charles Bonnet syndrome (β = 0.501, t(388) = 5.59, P < 0.001). Family physicians who provided counselling and education for patients had a significantly higher frequency of patients with visual hallucinations in their practice (P = 0.012, P < 0.001). Family physicians who referred their patients to geriatricians also saw patients with visual hallucinations in their practice more frequently (P = 0.04). No other significant associations were noted. Study limitations While a faxed survey has the advantage of a better response rate, it does bring into question whether the list of doctors with fax machines is truly representative of the total population. Since the survey background explains what Charles Bonnet syndrome is, this may elicit a higher response from respondents saying they were aware of the condition as their memory has been stimulated by the introduction. The survey did not probe to see how long doctors had been in practice, so it was not possible to determine if doctors had been taught about Charles Bonnet syndrome and had forgotten over time. Doctors did not access their records to determine how often they saw patients with visual hallucinations. For this reason, responses to this question must be interpreted as indicative of a practice pattern only. Conclusion The results indicate that there is a great lack of knowledge about Charles Bonnet syndrome among family physicians with more than half of respondents never having heard of this condition even though it is relatively common in that it affects around one in five people who have experienced vision loss. Of those who had heard of Charles Bonnet syndrome, only one in four had heard of the condition in their medical training. The lack of education about Charles Bonnet syndrome was further reflected in the open-ended question in which many respondents suggested that there was a need for more education about Charles Bonnet syndrome. Part of the challenge is that about three quarters of individual physicians saw patients with visual hallucinations once a year or less often. We tested whether awareness was greater among respondents who saw patients with visual hallucinations more often and found that the frequency with which a respondent saw patients with visual hallucinations was significantly associated with awareness by physicians of Charles Bonnet syndrome. Of the respondents who saw patients with visual hallucinations, most provided counselling or education. The frequency with which family physicians saw patients with visual hallucinations in their practice was associated with their likelihood of providing education and counselling. As discussed previously, education and counselling are the mainstays of treatment of Charles Bonnet syndrome. It is important that family physicians be aware of Charles Bonnet syndrome, to provide the appropriate counselling for patients with vision loss experiencing visual hallucinations. About a third of respondents in this study referred patients to a psychiatrist, a quarter to an ophthalmologist and about one in six to a neurologist. Referrals to geriatricians were also more likely to be made by family physicians who saw patients with visual hallucinations more frequently. Although Charles Bonnet syndrome itself is relatively benign, it is important that a differential diagnosis be made to rule out other causes of hallucinations. Almost all respondents never discussed Charles Bonnet syndrome as a possibility with patients who have experienced severe vision loss. Considering that many patients are reluctant to tell their doctors that they are experiencing hallucinations, it is important that family physicians are prepared to discuss this possibility with patients who may experience Charles Bonnet syndrome. Family physicians can play a significant role in helping patients who experience visual hallucinations overcome their fear of this condition by reassuring them that many patients who have lost significant vision experience hallucinations and that there is no connection to a mental disorder. Family physicians may also refer patients with visual hallucinations to the appropriate specialist, to rule out any other cause of visual hallucinations. It is hoped that increasing awareness of Charles Bonnet syndrome among family physicians will help increase awareness of the condition among patients and their families so that very few people have to feel that they are ‘going crazy’ when they experience these hallucinations. Declaration Funding: This study has been supported by an educational grant from Bayer Canada. Ethical approval: Research ethics board (REB) approval was granted through the University of Toronto. Conflict of interest: The authors have no conflicts of interest to declare. References 1. Bonnet C. Essai Analytique Sur Les Facultés De L’Ame: 6; Copenhague . 1760 . 2. Gordon KD . Prevalence of visual hallucinations in a national low vision client population . Can J Ophthalmol 2016 ; 51 : 3 – 6 . Google Scholar Crossref Search ADS PubMed 3. Wilkinson F . Auras and other hallucinations: windows on the visual brain . Prog Brain Res 2004 ; 144 : 305 – 20 . Google Scholar Crossref Search ADS PubMed 4. Gilmour G , Schreiber C , Ewing C . An examination of the relationship between low vision and Charles Bonnet syndrome . Can J Ophthalmol 2009 ; 44 : 49 – 52 . Google Scholar Crossref Search ADS PubMed 5. Schultz G , Melzack R . The Charles Bonnet syndrome: ‘phantom visual images’ . Perception 1991 ; 20 : 809 – 25 . Google Scholar Crossref Search ADS PubMed 6. Teunisse RJ , Cruysberg JR , Hoefnagels WH , Verbeek AL , Zitman FG . Visual hallucinations in psychologically normal people: Charles Bonnet’s syndrome . Lancet 1996 ; 347 : 794 – 7 . Google Scholar Crossref Search ADS PubMed 7. Menon GJ , Rahman I , Menon SJ , Dutton GN . Complex visual hallucinations in the visually impaired: the Charles Bonnet syndrome . Surv Ophthalmol 2003 ; 48 : 58 – 72 . Google Scholar Crossref Search ADS PubMed 8. Cox TM , ffytche DH . Negative outcome Charles Bonnet syndrome . Br J Ophthalmol 2014 ; 98 : 1236 – 9 . Google Scholar Crossref Search ADS PubMed 9. Jackson ML , Bassett KL . The natural history of the Charles Bonnet syndrome. Do the hallucinations go away ? Eye (Lond) 2010 ; 24 : 1303 – 4 . Google Scholar Crossref Search ADS PubMed 10. Holroyd S , Rabins PV . A three-year follow-up study of visual hallucinations in patients with macular degeneration . J Nerv Ment Dis 1996 ; 184 : 188 – 9 . Google Scholar Crossref Search ADS PubMed 11. Jan T , Del Castillo J . Visual hallucinations: Charles Bonnet syndrome . West J Emerg Med 2012 ; 13 : 544 – 7 . Google Scholar Crossref Search ADS PubMed 12. Vukicevic M , Fitzmaurice K . Butterflies and black lacy patterns: the prevalence and characteristics of Charles Bonnet hallucinations in an Australian population . Clin Exp Ophthalmol 2008 ; 36 : 659 – 65 . Google Scholar Crossref Search ADS PubMed 13. Nguyen ND , Osterweil D , Hoffman J . Charles Bonnet syndrome: treating nonpsychiatric hallucinations . Consult Pharm 2013 ; 28 : 184 – 8 . Google Scholar Crossref Search ADS PubMed 14. Eperjesi F , Akbarali N . 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Journal

Family PracticeOxford University Press

Published: Sep 18, 2018

References

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