Postmarketing surveillance: accuracy of patient drug attribution judgments

Confidence and accuracy in identification of adverse drug reactions reported by outpatients

Background Patient reporting of adverse drug reactions (ADRs) could supplement the existing reporting system and contribute to early detection of ADRs. The confidence in ADR identification and their attribution of ADRs were limited to outpatients. Objective To determine the type and frequency of ADRs reported by outpatients, to evaluate confidence and accuracy in ADR identification as well as contributing factors. Setting University hospital in northeastern Thailand Method Cross-sectional study using questionnaires distributed to 500 outpatients who claimed to have experienced an ADR. Confidence in identifying ADRs was measured by visual analogue score (VAS), while accuracy of reported ADRs was determined using Naranjo algorithm and WHO criteria. Main outcome measure Number and type of ADRs, confidence rating and accuracy category. Results In total, 390 outpatients completed the questionnaire (response rate = 78.0%). Rash (19.0%), nausea/vomiting (7.4%), and dizziness (5.8%) were the top three reported ADRs. Sixty-one percent of respondents rated their level of confidence in identifying ADRs as high (VAS 9.2 ± 0.95), which was associated with having underlying diseases (OR 1.93), low number of reported symptoms (OR 0.38) and severe ADRs (OR 1.33). Causality assessment was classified as true ADRs in 90.0% and 88.9% of cases, using Naranjo algorithm and WHO criteria, respectively. Respondents with low number of reported symptoms (OR 0.27) and high level of confidence had greater accuracy in ADR identification (OR 1.11). Conclusion The outpatients reported a high proportion of potential ADRs with high confidence and accuracy. Patient reporting of ADRs has potential to support the pharmacovigilance system.

Eliciting adverse effects data from participants in clinical trials

BACKGROUND

Analysis of drug safety in clinical trials involves assessing adverse events (AEs) individually or by aggregate statistical synthesis to provide evidence of likely adverse drug reactions (ADR). While some AEs may be ascertained from physical examinations or tests, there is great reliance on reports from participants to detect subjective symptoms, where he/she is often the only source of information. There is no consensus on how these reports should be elicited, although it is known that questioning methods influence the extent and nature of data detected. This leaves room for measurement error and undermines comparisons between studies and pooled analyses. This review investigated comparisons of methods used in trials to elicit participant-reported AEs. This should contribute to knowledge about the methodological challenges and possible solutions for achieving better, or more consistent, AE ascertainment in trials.

OBJECTIVES

To systematically review the research that has compared methods used within clinical drug trials (or methods that would be specific for such trials) to elicit information about AEs defined in the protocol or in the planning for the trial.

SEARCH METHODS

Databases (searched to March 2015 unless indicated otherwise) included: Embase; MEDLINE; MEDLINE in Process and Other Non-Indexed Citations; Cochrane Methodology Register (July 2012); Cochrane Central Register of Controlled Trials (February 2015); Cochrane Database of Systematic Reviews; Database of Abstracts of Reviews of Effects (January 2015); Health Technology Assessment database (January 2015); CINAHL; CAB Abstracts; BIOSIS (July 2013); Science Citation Index; Social Science Citation Index; Conference Proceedings Citation Index - Science. The search used thesaurus headings and synonyms for the following concepts: (A): Adverse events AND measurement; (B): Participants AND elicitation (also other synonyms for extraction of information about adverse effects from people); (C): Participants AND checklists (also other synonyms as for B). Pragmatic ways were used to limit the results whilst trying to maintain sensitivity. There were no date or sample size restrictions but only reports published in English were included fully, because of resource constraints as regards translation.

SELECTION CRITERIA

Two types of studies were included: drug trials comparing two or more methods within- or between-participants to elicit participant-reported AEs, and research studies performed outside the context of a trial to compare methods which could be used in trials (evidenced by reference to such applicability). Primary outcome data included AEs elicited from participants taking part in any such clinical trial. We included any participant-reported data relevant for an assessment of drug-related harm, using the original authors' terminology (and definition, where available), with comment on whether the data were likely to be treatment-emergent AEs or not.

DATA COLLECTION AND ANALYSIS

Titles and abstracts were independently reviewed for eligibility. Full texts of potentially eligible citations were independently reviewed for final eligibility. Relevant data were extracted and subjected to a 100% check. Disagreements were resolved by discussion, involving a third author. The risk of bias was independently assessed by two authors. The Cochrane 'Risk of bias' tool was used for reports comparing outcomes between participants, while for within-participant comparisons, each study was critically evaluated in terms of potential impact of the design and conduct on findings using the framework of selection, performance, detection, attrition, reporting, and other biases. An attempt was made to contact authors to retrieve protocols or specific relevant missing information. Reports were not excluded on the basis of quality unless data for outcomes were impossible to compare (e.g. where denominators differed). A narrative synthesis was conducted because differences in study design and presentation meant that a quantitative meta-analysis was not possible.

MAIN RESULTS

The 33 eligible studies largely compared open questions with checklist-type questions or rating scales. Two included participant interviews. Despite different designs, populations and details of questioning methods, the narrative review showed that more specific questioning of participants led to more AEs detected compared to a more general enquiry. A subset of six studies suggested that more severe, bothersome, or otherwise clinically relevant AEs were reported when an initial open enquiry was used, while some less severe, bothersome, or clinically relevant AEs were only reported with a subsequent specific enquiry. However, two studies showed that quite severe or debilitating AEs were only detected by an interview, while other studies did not find a difference in the nature of AEs between elicitation methods. No conclusions could be made regarding the impact of question method on the ability to detect a statistically significant difference between study groups. There was no common statistical rubric, but we were able to represent some effect measures as a risk ratio of the proportion of participants with at least one AE. This showed a lower level of reporting for open questions (O) compared to checklists (CL), with a range for the risk ratios of 0.12 to 0.64.

AUTHORS' CONCLUSIONS

This review supports concerns that methods to elicit participant-reported AEs influence the detection of these data. There was a risk for under-detection of AEs in studies using a more general elicitation method compared to those using a comprehensive method. These AEs may be important from a clinical perspective or for patients. This under-detection could compromise ability to pool AE data. However, the impact on the nature of the AE detected by different methods is unclear. The wide variety and low quality of methods to compare elicitation strategies limited this review. Future studies would be improved by using and reporting clear definitions and terminology for AEs (and other important variables), frequency and time period over which they were ascertained, how they were graded, assessed for a relationship to the study drug, coded, and tabulated/reported. While the many potential AE endpoints in a trial may preclude the development of general AE patient-reported outcome measurement instruments, much could also be learnt from how these employ both quantitative and qualitative methods to better understand data elicited. Any chosen questioning method needs to be feasible for use by both staff and participants.

Age Effects on Patient Drug Attribution Judgments

Data were obtained on patients' attribution of symptoms using two different post-marketing surveillance methods. In the patient-initiated method, outpatients were randomly assigned to have a printed notice conspicuously attached to the outside of their medication bags; the "outsert" requested the patients to monitor themselves during the next 2 weeks and to report via a toll-free telephone number any new or unusual symptoms. In the staff-initiated method, other patients filling the same target drug prescriptions did not receive any outsert but were identified at the pharmacy for a telephone interview 10 to 14 days later. The target drugs were chosen from two classes for which the major adverse drug reactions (ADRs) are well identified: oral antibiotics and tricyclic antidepressants. During the interview, for each reported symptom the patient was asked whether it might have been caused by the target drug. Results indicated that older patients, irrespective of the surveillance method or the drug class, appear to be capable of discriminating probable ADRs at least as well as or possibly better than younger patients.

Mood, Personality, and Behavior Changes During Treatment with Statins: A Case Series

Psychiatric adverse drug reactions (ADRs) have been reported with statin use, but the literature regarding statin-associated mood/behavioral changes remains limited. We sought to elicit information germane to natural history and characteristics of central nervous system/behavioral changes in apparent connection with statin and/or cholesterol-lowering drug use, and delineate mechanisms that may bear on an association. Participants (and/or proxies) self-referred with behavioral and/or mood changes in apparent association with statins completed a survey eliciting cholesterol-lowering drug history, character and impact of behavioral/mood effect, time-course of onset and recovery in relation to drug use/modification, co-occurrence of recognized statin-associated ADRs, and factors relevant to ADR causality determination. Naranjo presumptive ADR causality criteria were assessed. Participants (n = 12) reported mood/behavior change that commenced following statin initiation and persisted or progressed with continued use. Reported problems included violent ideation, irritability, depression, and suicide. Problems resolved with drug discontinuation and recurred with rechallenge where attempted. Eight met presumptive criteria for “probable” or “definite” causality; others had additional factors not considered in Naranjo criteria that bear on casual likelihood. (1) Simvastatin 80 mg was followed in 5 days by irritability/depression culminating in suicide in a man in his 40s (Naranjo criteria: possible causality). (2) Simvastatin 10 mg was followed within 2 weeks by depression in a woman in her 50s (probable causality). (3) Atorvastatin 20 mg was followed in ~1 month by depression and irritability/aggression in a male in his 50s (probable causality). (4) Atorvastatin 10 mg was followed in several months by aggression/irritability and depression culminating in suicide in a man in his 40s (possible causality). (5) Fenofibrate + rosuvastatin (unknown dose), later combined with atorvastatin were followed in 1 month by aggression/irritability in a male in his 30s (probable causality). (6) Lovastatin (unknown dose and time-course to reaction) was followed by depression, dyscontrol of bipolar disorder, and suicide attempts in a male in his 40s (possible causality). (7) Atorvastatin 20 mg was followed within 2 weeks by cognitive compromise, and nightmares, depression, and anxiety culminating in suicide in a man in his teens (definite causality). (8) Simvastatin 10 mg was followed (time-course not recalled) by depression, aggression/irritability culminating in suicide in a man in his 60s (possible causality). (9) Simvastatin 20 mg then atorvastatin 10 mg were followed (time-course not provided) by irritability/aggression in a man in his 60s (definite causality). (10) Atorvastatin 10 then 20 then 40 mg were followed shortly after the dose increase by violent ideation and anxiety in a man in his 30s (probable causality). (11) Atorvastatin 20 mg and then simvastatin 20 mg were followed in 2 weeks by aggression/irritability in a man in his 50s (definite causality). (12) Lovastatin, rosuvastatin, atorvastatin, and simvastatin at varying doses were followed as quickly as 1 day by aggression, irritability, and violent ideation in a man in his 40s (definite causality). Most had risk factors for statin ADRs, and co-occurrence of other, recognized statin ADRs. ADRs had implications for marriages, careers, and safety of self and others. These observations support the potential for adverse mood and behavioral change in some individuals with statin use, extend the limited literature on such effects, and provide impetus for further investigation into these presumptive ADRs. Potential mechanisms are reviewed, including hypothesized mechanisms related to oxidative stress and bioenergetics.

Initial development and testing of an instrument for patient self-assessment of adverse drug reactions

PURPOSE

To develop and conduct preliminary testing of a causality assessment tool for patients, for potential use in encouraging both discussions with clinicians about suspected adverse drug reactions (ADRs) and reporting to authorities.

METHODS

Ten causality statements, developed from qualitative studies involving patients, with a scoring system allowing categorization, were embedded in a questionnaire which also included a symptom checklist and additional details about one suspected ADR and medicine, selected for causality assessment. Patients with experiences of suspected ADRs were involved in cognitive interviews (15), piloting (20) and psychometric testing (120). Test-retest reliability, construct validity and criterion-related validity were evaluated, through repeated causality assessment, comparison with a visual analogue scale assessing certainty of causality and comparison with causality assessment using World Health Organization-Uppsala Monitoring Centre (WHO-UMC) criteria, respectively. The study involved outpatients at a university hospital in northeast Thailand.

RESULTS

Ninety-eight patients completed causality assessment twice: both causality scores (Spearman rs  = 0.715; p < 0.001) and causality classification [percentage of positive agreement (PPA) = 68.4; κ = 0.419; p < 0.001] showed satisfactory reliability. Causality scores were positively correlated with certainty of causality (Spearman rs  = 0.556; p < 0.01). There was moderate agreement against WHO-UMC criteria [PPA = 70.4; κ = 0.440; p < 0.001]. Of the 91 completing an evaluation, 88% agreed that the tool should be used routinely, 78% agreed that it gave them useful results and 80% agreed that it was easy to use.

CONCLUSIONS

This novel instrument has satisfactory psychometric properties and was acceptable to Thai patients, but it requires further testing. It has potential for use in supporting patients with suspected ADRs to discuss these with health professionals, and perhaps to report directly.

A qualitative study to explore how patients identify and assess symptoms as adverse drug reactions

PURPOSE

To explore how Thai patients assess symptoms as adverse drug reactions (ADRs).

METHODS

Out-patients at two hospitals in Thailand previously reporting suspected ADRs to statins were purposively selected to cover factors relevant to the accuracy of ADR reports. Semi-structured interviews explored the mechanisms participants used to work out whether their symptoms were related to their statin. All interviews were audio-recorded, transcribed and independently thematically analyzed by two researchers.

RESULTS

One hundred interviews were suitable for analysis; 52 were male, age range was 36 to 77 years (mean ± S.D.: 59.83 ± 9.14) and most (92) were taking other medicines in addition to statins. Patient assessment of symptoms as ADRs fell into two major themes: medicine-related factors and external factors. Timing relationships were mentioned most frequently (74), followed by information received (55), seeing similar symptoms in others (7) and diagnosis through blood tests (4). Use of multiple medicines, consideration of the medicine versus diseases, symptoms occurring with more than one medicine or relieved through treatment reduced confidence in ADR attribution. Many participants proposed alternative explanations for symptoms, including old age. Lack of information and knowledge were obstacles to the assessment process.

CONCLUSIONS

Patients assessed possible ADRs most often by considering timing relationships. While they also used medicine information, Thai patients received inadequate information to help them assess their symptoms. Patients expressed uncertainty and difficulties in deciding attribution when concomitant medicines and diseases were involved. The findings could support the development of a patient-friendly systematic tool for identifying and assessing possible ADRs.

Patient reporting of suspected adverse drug reactions to antiepileptic drugs: factors affecting attribution accuracy

This study was aimed to assess the frequency and number of suspected ADRs reported by patients taking antiepileptic drugs (AEDs) and to explore the factors that may affect patients' symptom attribution accuracy. A validated questionnaire containing an extensively checklist of symptoms was distributed to outpatients prescribed one or more AEDs. Data on concomitant drugs and diseases were obtained from outpatient records. All symptoms identified were assessed for causality. Of 1388 questionnaires distributed to 1214 patients, 830 completed questionnaires were returned (59.8%) from 727 patients. In total, 7815 symptoms were identified on 757 questionnaires (91.2%). Symptom severity ratings were positively related to the number of symptoms reported (p=0.003). Causality assessment found that 71.9% of the symptoms were 'true' ADRs and 28.1% were 'false' ADRs. Attribution accuracy was primarily influenced by the number of symptoms identified and indication for AED therapy, fewer symptoms and use for non-epilepsy indications being associated with greater attribution accuracy.

Efficacy and gastrointestinal risk of aspirin used for the treatment of pain and cold

AIMS

To analyse major sources of evidence-based information on the efficacy and gastrointestinal tolerability of aspirin, used short-term, in over-the-counter (OTC) doses, to relieve acute pain and cold symptoms, including associated feverishness.

METHODS

Evidence was largely collected from published meta-analyses and systematic reviews that focused on randomised, controlled, double-blind clinical trials, in which aspirin was compared to placebo and, in some cases also, to active comparators such as OTC doses of paracetamol or ibuprofen.

RESULTS

Across a large number of comparisons, aspirin was superior to placebo in treating pain, cold or fever. Efficacy was essentially similar to that of comparators used in equivalent doses. There was no serious GI adverse event attributed to ASA in any study, but mild-to-moderate dyspepsia in small percentages of cases was commonly reported.

CONCLUSION

OTC aspirin is safe and effective. Safety concerns should not limit brief use to relieve acute pain, cold or fever.

Statin-associated muscle-related adverse effects: a case series of 354 patients

STUDY OBJECTIVE

To characterize the properties and natural history of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (statin)-associated muscle-related adverse effects (MAEs).

DESIGN

Patient-targeted postmarketing adverse-effect surveillance approach coupling survey design with an open-ended narrative.

SETTING

University-affiliated health care system.

SUBJECTS

Three hundred fifty-four patients (age range 34-86 yrs) who self-reported muscle-related problems associated with statin therapy.

MEASUREMENTS AND MAIN RESULTS

Patients with perceived statin-associated MAEs completed a survey assessing statin drugs and dosages; characteristics of the MAEs; time course of onset, resolution, or recurrence; and impact on quality of life (QOL). Cases were assessed for putative drug adverse-effect causality by using the Naranjo adverse drug reaction probability scale criteria and were evaluated for inclusion in groups for which mortality benefit with statins has been shown. Patients reported muscle pain (93%), fatigue (88%), and weakness (85%). Three hundred patients (85%) met literature criteria for probable or definite drug adverse-effect causality. Ninety-four percent of atorvastatin usages (240/255) generated MAEs versus 61% of lovastatin usages (38/62, p<0.0001). Higher potency statins reproduced MAEs in 100% of 39 rechallenges versus 73% (29/40) with lower potency rechallenges (p<0.01). Time course of onset after statin initiation varied (median 14 wks); some MAEs occurred after long-term symptom-free use. Recurrence with rechallenge had a significantly shorter latency to onset (median 2 wks). The MAEs adversely affected all assessed functional and QOL domains. Most patients with probable or definite MAEs were in categories for which available randomized controlled trial evidence shows no trend to all-cause mortality benefit with statin therapy.

CONCLUSION

This study complements available information on the properties and natural history of statin-associated MAEs, affirming dose dependence and strong QOL impact. The data indicating a dose-dependent relationship between MAE risk and recurrence suggest lower potency statins or discontinuation may bear consideration for ameliorating symptoms.

Amyotrophic lateral sclerosis-like conditions in possible association with cholesterol-lowering drugs: an analysis of patient reports to the University of California, San Diego (UCSD) Statin Effects Study

BACKGROUND

While cases of amyotrophic lateral sclerosis (ALS) or ALS-like conditions have arisen in apparent association with HMG-CoA reductase inhibitors ('statins') and/or other lipid-lowering drugs (collectively termed 'statins' in this paper for brevity), additional information is needed to understand whether the connection may be causal. The University of California, San Diego (UCSD) Statin Effects Study is a patient-targeted adverse event surveillance project focused on lipid-lowering agents, whose aim is to capitalize on patient reporting to further define characteristics and natural history of statin adverse effects (AEs), and to ascertain whether a patient-targeted surveillance system might lead to presumptive identification of previously unrecognized AEs. ALS was a candidate 'new' AE identified through this process. The aim of the analysis presented here was to examine characteristics and natural history of reported statin-associated ALS-like conditions with attention to factors that may bear on the issue of causality.

METHODS

For the present analysis, we focused on cases of statin-associated ALS that were reported to our study group prior to publication of a possible statin-ALS association. Of 35 identified subjects who had contacted the UCSD Statin Effects Study group to report ALS or an ALS-like condition, 18 could not be reached (e.g. contact information was no longer valid). Six were unable to participate (e.g. due to progression of their disease). Of the 11 who could be contacted and were able to participate, one declined to give informed consent. The remaining ten, with either a formal or probable diagnosis of ALS in the context of progressive muscle wasting/weakness arising in association with lipid-lowering drug therapy, completed a mail or phone survey eliciting information about ALS symptom onset and change in association with drug use/modification and development of statin-associated AEs. We reviewed findings in the context of literature on statin antioxidant/pro-oxidant balance, as well as ALS mechanisms involving oxidative stress and mitochondrial dysfunction.

RESULTS

All ten subjects reported amelioration of symptoms with drug discontinuation and/or onset or exacerbation of symptoms with drug change, rechallenge or dose increase. Three subjects initiated coenzyme Q10 supplementation; all reported initial benefit. All subjects reportedly developed statin AEs (not indicative of ALS) prior to ALS symptom onset, strongly disproportionate to expectation (p < 0.001). Since this reflects induction of pro-oxidant effects from statins, these findings lend weight to a literature-supported mechanism by which induction by statins of oxidative stress with amplification of mitochondrial dysfunction, arising in a vulnerable subgroup, may propel mechanisms underlying both AEs and, more rarely, ALS.

CONCLUSION

A theoretical foundation and preliminary clinical observations suggest that statins (and other lipid-lowering drugs) may rarely be associated with ALS in vulnerable individuals in whom pro-oxidant effects of statins predominate. Our observations have explanatory relevance extending to ALS causes that are not statin associated and to statin-associated neurodegenerative conditions that are not ALS. They suggest means for identification of a possible vulnerable subgroup. Indeed whether statins may, in contrast, confer ALS protection when antioxidant effects predominate merits examination.

Adverse reactions related to drugs for headache treatment: clinical impact

OBJECTIVE

To assess the clinical impact of adverse reactions related to drugs for primary headache treatment.

METHODS

We examined the adverse reactions to 360 medications prescribed by the specialists of the Headache Centre of the University of Modena and Reggio Emilia to 256 consecutive outpatients (214 female, 42 male; mean age: 38.88 +/- 14.06 years; range 10-72 years). Adverse reactions were reported by patients during scheduled follow-up visits, classified by specialists and reassessed by a clinical pharmacologist.

RESULTS

Adverse reactions with a causal relationship classified as definite/probable/possible were 202 (56%): 62% (80/129) were due to acute treatments and 53% (122/231) to prophylactic treatments (chi2 test, P = 0.115 ns). More than 90% of the adverse reactions were of limited intensity [mild (58%) or moderate (36%)]. Only 5% were severe, and two reactions (1%) were serious. The most affected apparatus was the nervous system (41%). Of these adverse reactions, 43% caused the discontinuance of the treatment, especially of prophylaxis (54%). Patients evaluated 70% of the medications as effective, but, at the same time, they considered most of the adverse reactions (69%) unacceptable.

CONCLUSION

Adverse reactions related to headache medications have a strong impact on patients' management, even if their real intensity and severity are usually very limited. Drugs for headache treatment are still far from being ideal drugs. To prevent the discontinuance of effective medications, the physician, prior to prescribing, should assess, together with the patient, the acceptability of the more common adverse drug reactions.

A large simple clinical trial prototype for assessment of OTC drug effects using patient-reported data

PURPOSE

Innovative methods are needed to assess risks related to treatment for common medical conditions, where therapy is usually patient-directed or over-the-counter (OTC), and where tolerability, i.e. patient experienced events, may affect patterns of use. A large-scale, blinded, randomised trial was conducted to compare the tolerability of paracetamol (acetaminophen), aspirin and ibuprofen at OTC doses, with patient-reported adverse event (AE) data as the primary outcome.

METHODS

Patients with mild to moderate pain were randomised to either: paracetamol up to 3 g/d, aspirin up to 3 g/d or ibuprofen up to 1200 mg/d for 7 days. Patients recorded AE and severity in a diary as the primary data source. After inclusion, contact with patients by general practitioner (GP) investigators was by telephone after 24 hours and 7-9 days, and unscheduled visits, when GPs recorded AE. The study outcome was the frequency of significant adverse event (SGAE) (serious, severe, moderate or undefined intensity, or resulting in withdrawal or an investigator visit).

RESULTS

Of 8677 patients included, 44 patients were non-evaluable, leaving 8633 evaluable patients; 1347 patients reported SGAE (paracetamol: 14.5%, aspirin: 18.7%, ibuprofen: 13.7%). Completed diaries were returned by 98.5% of patients, and only 49 cases were lost to follow-up (0.6%). Almost all patients were contacted by telephone, 99.3% at the first call, and 98.5% at the second. Most SGAE were reported by patients; only 27 patients (2%) had a SGAE reported only by the GP. The tolerability rankings by treatment were consistent for all categories of SGAE: aspirin had the highest incidence of SGAE, and ibuprofen and paracetamol, lower, comparable incidences.

CONCLUSIONS

A large, simple, randomised trial with patient-generated data can provide a sensitive source of information on AE, particularly in comparative safety assessments of OTC medications and other short-term therapies. This suggests reconsideration of the view that investigators are the most valid source for identifying and reporting AE.

Review of national spontaneous reporting schemes. Strengths and weaknesses

OBJECTIVE

To investigate and compare the operation of different national spontaneous reporting schemes for adverse drug reactions.

DESIGN

Drug safety agencies in 18 countries were contacted by letter to request information about their spontaneous reporting scheme for adverse drug reactions. This information related to the background of the scheme, operational aspects of the scheme and numbers of reports received.

RESULTS

Replies were received from 12 countries. Many differences were found between the schemes operating in different countries. Some schemes had been in operation for over 30 years, while others were more recently established. While most schemes rely on voluntary reports, in two countries (France and Spain), reporting is a legal requirement for healthcare professionals. Reports are accepted from doctors, dentists and pharmacists in all of the countries surveyed; however the role of other health professionals and the general public was found to vary. There were also differences in the types of reactions for which reports are requested, and the products covered by the schemes. In some countries (e.g. Denmark) reports of all reactions are sought, while other countries focus on only serious reactions or reactions to newly marketed products. In Australia, there is a separate scheme for drug-induced congenital malformations and Canada, South Africa and the US run separate schemes for reactions to vaccines. However, other countries include these reactions in the general spontaneous reporting schemes. The numbers of reports received by the countries also varies considerably--from a few hundred each year in South Africa to over 20,000 in the US.

CONCLUSION

While the schemes all operate on the basic principle of collecting reports of adverse reactions to identify potential hazards, they showed many different approaches to the spontaneous reporting of adverse drug reactions. Features of one scheme may serve to improve reporting rates for another. In addition, all 12 countries participate in the World Health Organization International Drug Monitoring Programme, thus helping to inform the whole international community of drug safety problems.

Patient reporting of potential adverse drug reactions: a methodological study

AIMS

To develop a systematic generic method of enabling patients to report symptoms which they believe to be due to a particular prescribed drug.

METHODS

A piloted body system-based questionnaire was distributed to patients registered with 79 medical practices in Grampian prescribed one of nine recently marketed 'black triangle' drugs. These comprised four antidepressants, three antiepileptics and two analgesics. This requested respondents to identify any symptoms experienced over the previous year which they thought could be due to the 'black triangle' drug they had used. A sample of medical records was examined to compare symptoms recorded with those reported by patients. A classification system was developed for the study to enable the assessment of symptoms reported for their potential relationship to patients' drug therapy. All symptoms reported were classified, taking into account information provided by patients on their concomitant drugs and diseases. A specialist pharmacist independently re-classified a sample of the symptoms to validate the process.

RESULTS

A 36.3% response rate was obtained (837/2307) with 742 respondents (88.6%) reporting at least one symptom. The median per patient was 6.0 (range 0--71), with almost half (406, 48.5%) reporting fewer than five symptoms. Most symptoms (71.0%) were classified as being probably or possibly related to the drugs studied. Agreement between researcher and specialist on the classification of 75.3% of 716 symptoms was obtained (Kappa=0.563). Responses from patients prescribed antidepressant drugs were more likely to include symptoms potentially caused by these drugs (74.5% of all symptoms reported) than those from patients prescribed analgesics (67.4%) or antiepileptics (65.1%, chi2 = 23.858, d.f. = 2, P < 0.001). Patients reporting large numbers of symptoms were more likely to report some which were classed as unlikely to be an ADR or unattributable (chi2 = 80.587, d.f. = 3, P < 0.001). Of the 742 reporting symptoms in questionnaires, 402 (54.2%) claimed to have reported some or all of these to their doctor. Only 162 (22.6%) of 716 patient-reported symptoms were documented in the primary care medical records of 103 patients prescribed tramadol or venlafaxine.

CONCLUSIONS

Respondents were clearly willing to report symptoms, the majority of which were classed as possibly/probably related to the drugs studied. The results suggest that patients do not report all symptoms they suspect to be ADRs to their GP and that GPs do not record all symptoms which may be reported to them. The method could help to identify problems which patients perceive as being related to their drug therapy and contribute to increased ADR reporting.

How do pharmaceutical companies handle consumer adverse drug reaction reports? An overview based on a survey of French drug safety managers and officers

It is surprising to see how consumer Adverse Drug Reaction (ADR) reports have been continuously increasing for the last few years in Europe. This probably results from the influence of United States (US) market where the patients feels justified in telephoning the pharmaceutical companies directly with queries regarding their treatment. The growing number of alternative sources of information (e.g. health and popular magazines, spots on radio and TV etc.) to which a consumer is exposed has added to this growth too. The changing relationship between patients and doctors may also contribute to this phenomenon. It is then interesting to evaluate the way pharmaceutical companies currently deal with consumer ADR reports. The management of consumer ADR reporting was investigated by means of a questionnaire sent to 46 French drug safety managers and drug safety officers (DSOs) of multinational pharmaceutical companies. The analysis of the survey stressed the fact that pharmaceutical companies should be prepared to face up to an increase in the number of consumer ADR reports. It clearly appears that the consumers who telephone to register side-effects should be forwarded to a trained DSO with medical or pharmaceutical background and the communication skills acquired through specific training. This person should also be able to release adequate product information validated by his/her own company. The influence of the US market seems to be changing the way pharmaceutical companies deal with consumer ADR reports. Nowadays, these reports are entered into a drug safety database by most of the companies without previously having contacted the patient's general practitioner (GP) or specialist for medical confirmation. Lastly, the drug safety managers and DSOs consulted have divided opinions about the usefulness of call centres and e-mails as tools for ADR reporting. But both tools are globally rejected by the pharmaceutical companies as a reliable means of reporting. As stated in this article, the reporting of ADRs via e-mail would cause real problems for the drug safety units. Finally, they consider that telephone call centres should be restricted to a specific communication problem such as crisis management or Dear Dr letters.

Comparative sexual side effects of bupropion, fluoxetine, paroxetine, and sertraline

OBJECTIVE

To investigate patient reported prosexual side effects of the aminoketone antidepressant bupropion (INN, amfebutamone) and to compare directly the sexual side effects of bupropion and the selective serotonin reuptake inhibitor (SSRI) antidepressants fluoxetine, paroxetine, and sertraline.

METHODS

One hundred seven psychiatric outpatient respondents receiving current treatment with one of the above antidepressants anonymously completed questionnaires that allowed reporting of both decreases and increases in sexual function. The main outcome measures were antidepressant-associated changes in libido, arousal, duration of time from arousal to orgasm, intensity of orgasm, and duration of orgasm relative to that experienced before the onset of the patients' psychiatric illnesses.

RESULTS

Bupropion-treated patients reported significant increases in libido, level of arousal, intensity of orgasm, and duration of orgasm beyond levels experienced premorbidly. The three SSRIs to an equal degree significantly decreased libido, arousal, duration of orgasm, and intensity of orgasm below levels experienced premorbidly. Overall, 27% of the SSRI-treated patients had no adverse sexual side effects; in contrast, 86% of patients treated with bupropion had no adverse sexual effects, and 77% of bupropion-treated patients reported at least one aspect of heightened sexual functioning.

CONCLUSIONS

SSRI-induced adverse sexual effects appear to be the rule rather than the exception and may be substantially underreported unless patients are specifically asked about the effects of these medications on various aspects of sexual function. In contrast, prosexual effects were reported by the majority of patients treated with bupropion. The findings are reviewed in light of the neurochemistry of these agents and the sexual response.

Experience in the development of a postmarketing surveillance network: the pharmacy medication monitoring program

OBJECTIVE

To describe the pilot and early implementation phase of a system for assembling and recruiting cohorts of patients taking selected prescription medications and prospectively monitoring them for new health events.

DESIGN

Prospective observational study, based on telephone interviews, of 1475 patients filling prescriptions for a nonsteroidal antiinflammatory drug (NSAID). Patients were interviewed by telephone using trained interviewers at a central site. Hospitalizations and deaths were followed up and reviewed by an independently physician.

SETTING

Community setting in a region of Hamilton, Ontario, Canada.

PARTICIPANTS

All consenting patients filling new or repeat prescriptions for NSAIDs at participating pharmacies.

MAIN OUTCOME MEASURES

The authors report on the development and assessment of systems for: (1) ongoing recruitment of patients through community pharmacies; (2) data transfer from pharmacies to the coordinating center; (3) surveying patients; (4) classifying, coding, and evaluating new health events; and (5) following up on new serious adverse events.

RESULTS

Fifty-one percent of patients approached were recruited, and 83% of these provided completed interviews. For patients picking up their own medications, pharmacy workload varied from 4 to 10 minutes per patient approached. Nineteen percent of patients reported having a new health problem or unusual symptom at the initial telephone interview. Reported health-related events were similar to those described in other studies of NSAIDs.

CONCLUSIONS

Most aspects of the monitoring system performed well. One limitation was the low recruitment rate for patients who did not directly drop off or pick up their own prescriptions. Even so, this method of patient accrual may complement alternative monitoring programs.