Only Low Patients' Expectations Are Prognostic for Dissatisfaction With Performing Work-Related Knee-Straining Activities After Total Knee Arthroplasty: A Prospective Multicenter Cohort Study.

OBJECTIVE: To investigate whether preoperative expectations regarding performing work-related knee-straining activities were associated with being dissatisfied 6 months after total knee arthroplasty (TKA) among working patients, and, to identify prognostic factors for being dissatisfied with performing these work-related knee-straining activities. DESIGN: Multicenter prospective cohort study. SETTING: Orthopedic surgery departments of 7 hospitals in the Netherlands. PARTICIPANTS: A consecutive sample of 175 working patients who were on the waiting list for TKA (median age 59 years, 53% women) and intended to return to work (N=175). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE(S): Dissatisfaction with performing work-related knee-straining activities 6 months postoperative was measured using the Work Osteoarthritis or joint-Replacement Questionnaire (score range 0-100). The clinically relevant cut-off points for being satisfied and dissatisfied were ≥71 and ≤50, respectively. RESULTS: Thirty-three patients (19%) were dissatisfied with performing work-related knee-straining activities 6 months after TKA. Patients who expected to be dissatisfied preoperative had a 5.1 times higher odds (95% CI 1.7-15.5) of being dissatisfied 6 months postoperatively compared with patients who expected to be satisfied preoperative. Regression analyses revealed that only patients' expectations were prognostic for being dissatisfied 6 months postoperatively rather than age, pain level, or having a knee-straining job. CONCLUSIONS: Two in 10 working patients are dissatisfied with performing work-related knee-straining activities 6 months after TKA. Only preoperative patients' expectations appeared prognostic. Therefore, we should better prepare working patients with low expectations by managing their preoperative expectations and improving their performance of work-related knee-straining activities in rehabilitation.

Thrombectomy Alone versus Bridging Therapy in Acute Ischemic Stroke: Preliminary Results of an Experimental Trial.

Background: For patients with acute large vessel occlusion (ALVO) in the anterior circulation who are able to undergo mechani-cal thrombectomy (MTB) within 4.5 hours, the need for intravenous thrombolysis prior to the intervention remains unclear. Methods: Patients who were eligible for intravenous thrombolysis, who presented with ALVO in the anterior circulation, and who started MTB within 4.5 hours were matched at a 1:1 ratio to a thrombectomy alone group or to a bridging therapy group. Patients in the bridging therapy group were administered intravenous alteplase at a standard dose of 0.9 mg/kg. We evaluated the safety and efficacy of the throm-bectomy alone group compared with the bridging therapy group. Results: From December 2020 to September 2021, 60 patients were recruited in the study and completed the trial. The baseline para-meters of patients were similar between the two groups. At the 90-day follow-up, 18 patients (60%) in the thrombectomy alone group versus 18 patients (60%) in the bridging therapy group achieved functional independence (odds ratio [OR]: 1, 95% confidence interval [CI], 0.36-2.81). The successful recanalization (Thrombolysis in Cerebral Infarction [TICI] grade 2b to 3) rates on final angiography were 90% and 86.7%, respectively (OR, 0.72, 95% CI, 0.15-3.55). No significant differences were found between the two groups in the occurrence of symptomatic intracranial hemorrhage or 90-day mortality. Conclusion: Our preliminary results did not show the superiority of thrombectomy alone versus standard bridging therapy in patients with ALVO in the anterior circulation who undergo MTB within 4.5 hours. A larger sample size and other randomized controlled trials remain necessary to validate these results.

Cannabis use is associated with patient and clinical factors in a population-based sample of colorectal cancer survivors.

PURPOSE: This study aimed to characterize patient and clinical factors associated with cannabis (marijuana) use among patients diagnosed with colorectal cancer (CRC). METHODS: We identified CRC patients, diagnosed from 2016 to 2018, using the Seattle-Puget Sound Surveillance, Epidemiology, and End Results (SEER) cancer registry. CRC patients were recruited via mail and telephone, and participants completed a questionnaire eliciting information on medical history, demographics, and lifestyle factors, including cannabis use. Cancer stage was obtained from SEER registry data. RESULTS: Of 1,433 survey respondents, 339 (24%) were current cannabis users. Current cannabis use was associated with younger age at diagnosis, lower BMI, and a higher prevalence of cigarette smoking and alcohol consumption (p-value < 0.05). Cannabis use was also associated with lower quality of life scores (FACT-C) and advanced-stage cancer (p-value < 0.05). CONCLUSION: Cannabis use among CRC patients was common. Patients with more advanced disease were more likely to report cannabis use. Use also varied by some personal factors, consistent with patterns in the general population. Given the high prevalence of cannabis use among CRC patients, research is needed to determine the benefits and harms of cannabis use for symptom management in cancer patients.

Wound complications after total hip arthroplasty: a prospective, randomised controlled trial comparing staples with sutures.

OBJECTIVE: Does the use of staples or sutures for wound closure have a lower surgical site infection rate in patients receiving primary total hip arthroplasty (THA)? DESIGN: Prospective, randomised controlled multicentre trial. METHODS: 535 patients undergoing THA were included and randomised into 2 groups: 268 wounds were closed with staples, and 267 with sutures. Primary outcome was surgical site infection (SSI). Secondary outcomes were prosthetic joint infection (PJI), other wound complications (dehiscence, necrosis and prolonged drainage) and duration of admittance. Follow-up occurred at 2, 6, and 12 weeks, and at 1 year. RESULTS: There were no significant demographic differences between the 2 groups. SSI occurred more frequently when wounds were closed with staples (4% compared to 1% with sutures; OR 2.8; CI, 0.885-0.952; p = 0.057). SSI was treated with oral antibiotics. The staples group showed significantly more wound complications (17% compared to 5%; OR 3.943, CI 2.073-7.498; p = 0.000). Wound discharge was significantly prolonged in the staples group (n = 40, compared to n = 12 in the sutures group; OR 3.728; CI, 1.909-7.281; p = 0.000). There was no significant difference in PJI (p = 0.364). CONCLUSIONS: In this large RCT comparing staples with sutures after THA, the use of staples is associated with a nearly 3 times greater risk of SSI (OR 2.8; p = 0.057). Staples significantly prolong wound discharge. The use of sutures for wound closure after THA is advised. Trial registration: Staples Or Sutures trial (S.O.S. trial) http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=3946 , NTR3946.

Genotype correlates with the natural history of severe bile salt export pump deficiency.

BACKGROUND & AIMS: Mutations in ABCB11 can cause deficiency of the bile salt export pump (BSEP), leading to cholestasis and end-stage liver disease. Owing to the rarity of the disease, the associations between genotype and natural history, or outcomes following surgical biliary diversion (SBD), remain elusive. We aimed to determine these associations by assembling the largest genetically defined cohort of patients with severe BSEP deficiency to date. METHODS: This multicentre, retrospective cohort study included 264 patients with homozygous or compound heterozygous pathological ABCB11 mutations. Patients were categorized according to genotypic severity (BSEP1, BSEP2, BSEP3). The predicted residual BSEP transport function decreased with each category. RESULTS: Genotype severity was strongly associated with native liver survival (NLS, BSEP1 median 20.4 years; BSEP2, 7.0 years; BSEP3, 3.5 years; p <0.001). At 15 years of age, the proportion of patients with hepatocellular carcinoma was 4% in BSEP1, 7% in BSEP2 and 34% in BSEP3 (p = 0.001). SBD was associated with significantly increased NLS (hazard ratio 0.50; 95% CI 0.27-0.94: p = 0.03) in BSEP1 and BSEP2. A serum bile acid concentration below 102 µmol/L or a decrease of at least 75%, each shortly after SBD, reliably predicted NLS of ≥15 years following SBD (each p <0.001). CONCLUSIONS: The genotype of severe BSEP deficiency strongly predicts long-term NLS, the risk of developing hepatocellular carcinoma, and the chance that SBD will increase NLS. Serum bile acid parameters shortly after SBD can predict long-term NLS. LAY SUMMARY: This study presents data from the largest genetically defined cohort of patients with severe bile salt export pump deficiency to date. The genotype of patients with severe bile salt export pump deficiency is associated with clinical outcomes and the success of therapeutic interventions. Therefore, genotypic data should be used to guide personalized clinical care throughout childhood and adulthood in patients with this disease.

Three Out of Ten Working Patients Expect No Clinical Improvement of Their Ability to Perform Work-Related Knee-Demanding Activities After Total Knee Arthroplasty: A Multicenter Study.

Purpose Three out of ten patients do not return to work after total knee arthroplasty (TKA). Patient expectations are suggested to play a key role. What are patients' expectations regarding the ability to perform work-related knee-demanding activities 6 months after TKA compared to their preoperative status? Methods A multi-center cross-sectional study was performed among 292 working patients listed for TKA. The Work Osteoarthritis or joint-Replacement Questionnaire (WORQ, range 0-100, minimal important difference 13) was used to assess the preoperatively experienced and expected ability to perform work-related knee-demanding activities 6 months postoperatively. Differences between the preoperative and expected WORQ scores were tested and the most difficult knee-demanding work-related activities were described. Results Two hundred thirty-six working patients (81%) completed the questionnaire. Patients' expected WORQ score (Median = 75, IQR 60-86) was significantly (p < 0.01) higher than their preoperative WORQ score (Median = 44, IQR 35-56). A clinical improvement in ability to perform work-related knee-demanding activities was expected by 72% of the patients, while 28% of the patients expected no clinical improvement or even worse ability to perform work-related knee-demanding activities 6 months after TKA. Of the patients, 34% expected severe difficulty in kneeling, 30% in crouching and 17% in clambering 6 months after TKA. Conclusions Most patients have high expectations, especially regarding activities involving deep knee flexion. Remarkably, three out of ten patients expect no clinical improvement or even a worse ability to perform work-related knee-demanding activities 6 months postoperatively compared to their preoperative status. Therefore, addressing patients expectations seems useful in order to assure realistic expectations regarding work activities.

Nationwide comprehensive gastro-intestinal cancer cohorts: the 3P initiative.

BACKGROUND: The increasing sub-classification of cancer patients due to more detailed molecular classification of tumors, and limitations of current trial designs, require innovative research designs. We present the design, governance and current standing of three comprehensive nationwide cohorts including pancreatic, esophageal/gastric, and colorectal cancer patients (NCT02070146). Multidisciplinary collection of clinical data, tumor tissue, blood samples, and patient-reported outcome (PRO) measures with a nationwide coverage, provides the infrastructure for future and novel trial designs and facilitates research to improve outcomes of gastrointestinal cancer patients. MATERIAL AND METHODS: All patients aged ≥18 years with pancreatic, esophageal/gastric or colorectal cancer are eligible. Patients provide informed consent for: (1) reuse of clinical data; (2) biobanking of primary tumor tissue; (3) collection of blood samples; (4) to be informed about relevant newly identified genomic aberrations; (5) collection of longitudinal PROs; and (6) to receive information on new interventional studies and possible participation in cohort multiple randomized controlled trials (cmRCT) in the future. RESULTS: In 2015, clinical data of 21,758 newly diagnosed patients were collected in the Netherlands Cancer Registry. Additional clinical data on the surgical procedures were registered in surgical audits for 13,845 patients. Within the first two years, tumor tissue and blood samples were obtained from 1507 patients; during this period, 1180 patients were included in the PRO registry. Response rate for PROs was 90%. The consent rate to receive information on new interventional studies and possible participation in cmRCTs in the future was >85%. The number of hospitals participating in the cohorts is steadily increasing. CONCLUSION: A comprehensive nationwide multidisciplinary gastrointestinal cancer cohort is feasible and surpasses the limitations of classical study designs. With this initiative, novel and innovative studies can be performed in an efficient, safe, and comprehensive setting.

[A former bodybuilder with a swelling on the forearm]. / Een oud-bodybuilder met een zwelling op de onderarm.

A 56-year-old man came to the general practitioner with a solitary compressible swelling on his left forearm, which enlarged during exercise. The patient reported a history of bodybuilding and he worked as a plasterer. Physical examination revealed primary varicose of the upper extremity, a rare localisation of a common vascular disease.

Outcome prediction in moderate and severe traumatic brain injury: a focus on computed tomography variables.

BACKGROUND: With this study we aimed to design validated outcome prediction models in moderate and severe traumatic brain injury (TBI) using demographic, clinical, and radiological parameters. METHODS: Seven hundred consecutive moderate or severe TBI patients were included in this observational prospective cohort study. After inclusion, clinical data were collected, initial head computed tomography (CT) scans were rated, and at 6 months outcome was determined using the extended Glasgow Outcome Scale. Multivariate binary logistic regression analysis was applied to evaluate the association between potential predictors and three different outcome endpoints. The prognostic models that resulted were externally validated in a national Dutch TBI cohort. RESULTS: In line with previous literature we identified age, pupil responses, Glasgow Coma Scale score and the occurrence of a hypotensive episode post-injury as predictors. Furthermore, several CT characteristics were associated with outcome; the aspect of the ambient cisterns being the most powerful. After external validation using Receiver Operating Characteristic (ROC) analysis our prediction models demonstrated adequate discriminative values, quantified by the area under the ROC curve, of 0.86 for death versus survival and 0.83 for unfavorable versus favorable outcome. Discriminative power was less for unfavorable outcome in survivors: 0.69. CONCLUSIONS: Outcome prediction in moderate and severe TBI might be improved using the models that were designed in this study. However, conventional demographic, clinical and CT variables proved insufficient to predict disability in surviving patients. The information that can be derived from our prediction rules is important for the selection and stratification of patients recruited into clinical TBI trials.

[Periodontal disease and quality of life]. / Parodontitis en levenskwaliteit.

In order to gain insight into the degree to which periodontal disease is related to quality of life, research was carried out among 85 patients with moderate or severe periodontal disease in which they were asked to complete the Oral Health Impact Profile-NL49. Their scores on this questionnaire were compared with the scores of 85 control subjects of comparable age and gender. The patients with periodontal disease demonstrated significantly worse scores compared to the control group and patients with severe periodontal disease had scores which were statistically significantly worse than patients with moderate periodontal disease. The results of this study suggest a causal negative association of periodontal disease with quality of life.

Computed tomography and outcome in moderate and severe traumatic brain injury: hematoma volume and midline shift revisited.

Intracranial lesion volume and midline shift are powerful outcome predictors in moderate and severe traumatic brain injury (TBI), and therefore they are used in TBI and computed tomography (CT) classification schemes, like the Traumatic Coma Data Bank (TCDB) classification. In this study we aimed to explore the prognostic value of lesion volume and midline shift in moderate and severe TBI as measured from acute cranial CT scans. Also, we wanted to determine interrater reliability for the evaluation of these CT abnormalities. We included all consecutive moderate and severe TBI patients admitted to our hospital who were aged ≥16 years, over an 8-year period, as part of the prospective Radboud University Brain Injury Cohort Study. Six months post-trauma we assessed outcomes using the Glasgow Outcome Scale-Extended (GOS-E). We analyzed 605 patients and found an association of both lesion volume and midline shift with outcome; increases were associated with a higher frequency of patients with an unfavorable outcome or death. A cut-off value, such as that used in the TCDB CT classification (lesion volume 25 mL and midline shift 5 mm), was not found. The average interrater difference in volume measurement was 6.8 mL, and it was 0.2 mm for the determination of degree of shift. Using lesion volume and midline shift as continuous variables in prognostic models might be preferable over the use of threshold values, although an association of these variables with outcome in relation to other CT abnormalities was not tested. The data provided here will be useful for stratification of patients enrolled in clinical trials of neuroprotective therapies.

(18)F-fluoro-L-thymidine-PET for the evaluation of primary brain tumours in children: a report of three cases.

BACKGROUND: F-fluoro-L-thymidine (FLT) has been shown to be a useful PET tracer in the evaluation of brain tumours in adults. No studies of this modality in children with brain tumours, however, have been published. OBJECTIVE: In this report three children with brain tumours are presented in which FLT-PET was used for different diagnostic purposes, in addition to imaging with MRI and F-fluorodeoxyglucose-PET. The first patient showed that FLT-PET could be helpful in differentiating between infection and malignancy. In the second patient FLT-PET was used for differentiating recurrent disease from radiotherapy effects. In the third patient, in which biopsy was not possible, FLT-PET was used for the characterization of the tumour. CONCLUSION: These patients show that FLT-PET might be a useful modality in different stages of the evaluation of primary brain tumours in children. However, further research to determine the clinical value, relative to MRI and fluorodeoxyglucose-PET, is required before routine implementation of FLT-PET.

The status of the fourth ventricle and ambient cisterns predict outcome in moderate and severe traumatic brain injury.

Computed tomography (CT) of the head has become the diagnostic tool of choice, particularly for moderate and severe traumatic brain injury (TBI). Various CT characteristics are associated with outcome, and may therefore be used as outcome predictors. One of the most prominent predictors appears to be the status of the basal cisterns. This study describes the prognostic value of the appearance of individual cisterns and ventricles in relation to that of the basal cisterns. Further, we determine the interrater and intrarater reliability in the evaluation of the cisterns and ventricles. All consecutive moderate and severe adult TBI patients admitted to our hospital were included in this study as part of the prospective Radboud University Brain Injury Cohort Study (RUBICS). Outcome was assessed at 6 months post-trauma using the Glasgow Outcome Scale-Extended (GOS-E). The predictive value of cisterns and ventricles was determined using multivariate binary logistic regression analysis. We included 126 moderate and 574 severe TBI patients. Absence (complete obliteration), but also compression of the ambient cisterns and/or the fourth ventricle were strongly related to unfavorable outcome and death and emerged as the only significant outcome predictors after multivariate analysis. The assessment of the ambient cisterns and the fourth ventricle had a satisfactory inter- and intrarater reliability (kappa coefficients: 0.80-0.95). We conclude that, because obliteration of the ambient cisterns and the fourth ventricle both are better than the status of the basal cisterns as outcome predictors, they might be used in CT prediction models in cases of moderate and severe TBI.

Outcome prediction in mild traumatic brain injury: age and clinical variables are stronger predictors than CT abnormalities.

Mild traumatic brain injury (mTBI) is a common heterogeneous neurological disorder with a wide range of possible clinical outcomes. Accurate prediction of outcome is desirable for optimal treatment. This study aimed both to identify the demographic, clinical, and computed tomographic (CT) characteristics associated with unfavorable outcome at 6 months after mTBI, and to design a prediction model for application in daily practice. All consecutive mTBI patients (Glasgow Coma Scale [GCS] score: 13-15) admitted to our hospital who were age 16 or older were included during an 8-year period as part of the prospective Radboud University Brain Injury Cohort Study (RUBICS). Outcome was assessed at 6 months post-trauma using the Glasgow Outcome Scale-Extended (GOSE), dichotomized into unfavorable (GOSE score 1-6) and favorable (GOSE score 7-8) outcome groups. The predictive value of several variables was determined using multivariate binary logistic regression analysis. We included 2784 mTBI patients and found CT abnormalities in 20.7% of the 1999 patients that underwent a head CT. Age, extracranial injuries, and day-of-injury alcohol intoxication proved to be the strongest outcome predictors. The presence of facial fractures and the number of hemorrhagic contusions emerged as CT predictors. Furthermore, we showed that the predictive value of a scheme based on a modified Injury Severity Score (ISS), alcohol intoxication, and age equalled the value of one that also included CT characteristics. In fact, it exceeded one that was based on CT characteristics alone. We conclude that, although valuable for the identification of the individual mTBI patient at risk for deterioration and eventual neurosurgical intervention, CT characteristics are imperfect predictors of outcome after mTBI.

Pharmacist-based medication review reduces potential drug-related problems in the elderly: the SMOG controlled trial.

BACKGROUND: The high prevalence of drug-related problems (DRPs) in the elderly, occurring as a result of multiple drug use combined with age-related changes in pharmacokinetics and pharmacodynamics, is a well known phenomenon. However, effective intervention strategies are uncommon. OBJECTIVE: A pharmacy-based controlled trial (SMOG [Screening Medicatie Oudere Geneesmiddelgebruiker; Screening Medications in the Older Drug User]) was performed to investigate whether a community pharmacist-led intervention reduces the number of potential DRPs in patients aged > or = 65 years using six or more drugs concomitantly. METHODS: This intervention study was conducted from June 2002 until June 2003 in 16 community pharmacies in the Netherlands. Medication assessment was undertaken in elderly patients aged > or = 65 years using six or more drugs concomitantly on the date of inclusion. Ten types of potential DRPs were determined and grouped into the following three categories: (i) patient-related potential DRPs: non-compliance; (ii) prescriber-related potential DRPs: expired indication, therapeutic duplication, inappropriate dosage (over- and under-dosage), off-label use, undertreatment, inconvenience of use; and (iii) drug-related potential DRPs: contraindications, drug-drug interactions, drug treatment of adverse drug reactions. A list of recommended changes in medication was compiled by the pharmacist for the patients in the intervention group. Recommendations for medication change were discussed with the general practitioner (GP). Four months after the date of inclusion, the medications of each patient were again reviewed and screened for potential DRPs. The primary outcome corresponded to the change in the number of potential DRPs; the secondary outcome was related to the change in number of used medications between the intervention group and the control group at baseline and 4 months later. RESULTS: A total of 174 patients were analysed: 87 patients in the intervention arm and 87 patients in the usual care arm. After a 4-month period, we observed a significant reduction in the mean number of DRPs per patient (mean difference -16.3%; 95% CI -24.3, -8.3). The mean number of drugs per patient was not significantly reduced (mean difference -4.7%; 95% CI -9.6, 0.2). CONCLUSION: This study showed a positive influence of the community pharmacist in reducing potential DRPs in the elderly. Future interventions should also focus on actual outcomes, including quality of life, morbidity and mortality.

Ranking of agricultural pesticides in the Rhine-Meuse-Scheldt basin based on toxic pressure in marine ecosystems.

Although risk assessments on a per-chemical basis are required during the registration procedure of pesticides, cumulative risks from the use of all pesticides on the variety of crops in a catchment area of a river are not assessed. The present study aimed to rank pesticides used in outdoor agricultural practice within the catchment of the rivers Rhine, Meuse, and Scheldt according to their potential toxic impact on the North Sea coastal ecosystem. Toxic pressure calculations (based on steady-state concentrations calculated with a multimedia fate model) and species-sensitivity distribution-based risk estimations were performed for pesticide emissions in the years 1998 (189 pesticides) and 2004 (133 pesticides). A ranking was established according to the relative contribution of single pesticides and crop types to the overall toxic pressure. Calculations were performed probabilistically to deal with parameter uncertainties. Only a few pesticides and crop types dominate overall toxic pressure because of emissions in both years, and the uncertainty appears to be caused largely by uncertainties in interspecies variances of aquatic toxicities. For 1998, these pesticides were fentin-acetate, with a median relative contribution (RCx) to the toxic pressure of multiple chemicals on an ecosystem of 0.43. For 2004, the pesticides that contributed most were pencycuron and paraquat-dichloride, with a median RCx, of 4.4 x 10(-2) and 3.9 x 10(-2), respectively. Pesticides applied to potato cropland and fruit trees contributed most to the overall toxic pressure.

[Skin eruptions as an adverse reaction to epidermal growth-factor receptor inhibitors]. / Huidafwijkingen als bijwerking van remmers van epidermale-groeifactorreceptor.

Inhibition of the epidermal growth-factor receptor (EGFR) is a new strategy in the treatment of solid malignancies. Two men, aged 65 and 59 years, with a metastasized renal carcinoma and a 51-year-old man with a metastasized melanoma developed an acneiform eruption during EGFR inhibition. The second and third patient also developed paronychia. Treatment in all patients consisted of antiseptics and topical antibiotics; the first and third patient also received an oral antibiotic. Withdrawal of the EGFR inhibitor because of progression of the disease led to complete recovery of the cutaneous lesions in the first and the third patient; both died after several months. In the second patient, the side effects reached an acceptable level during continued EGFR therapy. EGFR inhibition is usually accompanied by cutaneous side effects. An acneiform eruption is seen in up to 90% of all treated patients. Other side effects include dry skin, and nail and hair changes. The pathogenesis of these side effects is related to inhibition of EGFR signalling pathways in the skin, but is not yet fully understood. The treatment of EGFR inhibitor-mediated cutaneous toxicity is based mainly on clinical experience.

Identification of potential drug-related problems in the elderly: the role of the community pharmacist.

OBJECTIVE: The high prevalence of multiple drug use combined with age-related changes in pharmacokinetics and pharmacodynamics makes older adults more vulnerable to drug-related problems (DRPs). This pharmacy-based study was performed to identify potential DRPs from prescription records of the elderly and the role of the pharmacist in this process. METHOD: The study was performed from June 2002 to February 2003 in 16 community pharmacies in the Netherlands. Medication assessment of elderly patients aged 65 and over using six or more drugs concomitantly took place on the date of inclusion. Ten types of potential DRPs, grouped into three categories, were determined. The three groups were patient-related, prescriber-related or drug-related potential DRPs. We looked at the occurrence, nature and determinants of differential potential DRPs. RESULTS: The mean number of prescriptions per patient was 8.7. In total 3.9 potential DRPs per elderly person were identified. The distribution of the potential DRPs over the three categories was: patient related 4.7%, prescriber related 55.7% and drug related 39.6%. Use of NSAIDs (OR 29.9; 95% CI 4.1-219) and digoxin (OR 15.7; 95% CI 4.9-50.5) were associated with the highest risk for potential DRPs. CONCLUSION: In this vulnerable group of elderly patients potential DRPs frequently occur. Community pharmacists can play an important role in the identification, assessment and prevention of potential DRPs in the elderly. It is useful to investigate which part of potential DRPs can be avoided by the intervention of the community pharmacist in collaboration with the prescriber and the patient.