The prevalence and incidence of medical conditions in healthy pharmaceutical company employees who volunteer to participate in medical research

Aims Although clinical research in healthy volunteers is commonly performed there have been few studies of the value of the medical screening of subje cts. The aim of this study was to investigate the prevalence and incidence of medical conditions found during the medical screening of 'healthy' subje cts employed in a pharmaceutical company who volunteered to participate in medical research. Methods This was a retrospective study of the medical notes of all the subj ects who volunteered for membership of the Zeneca Clinical Pharmacology Uni t's healthy volunteer panel over a 4 year period from 1990 to 1994. The pre valence of medical conditions found at presentation was determined. The inc idence of medical conditions during the 4 year observation period was also ascertained. Medical screening included a full medical history and examinat ion, clinical chemistry, haematology and urinalysis screens, pulmonary func tion tests, ECGs, 24 h ambulatory cardiac monitoring and a request for info rmation from the volunteer's General Practitioner. Results Prevalence-1293 subjects volunteered to join the panel of which 156 subjects (12%) were not accepted at presentation including 141 (10.9%) for medical reasons. The most medical common reasons were; previously diagnose d medical conditions (3.3%), cardiovascular abnormalities (1.9%), abnormal liver function tests (1.9%) anaemia (1.2%), hyperlipidaemia (1.1%) excess a lcohol intake (0.6%) and thyroid disease (0.5%). Incidence-36 of the 1137 v olunteers (0.8% per year) accepted onto the panel subsequently developed me dical conditions of which the most common were; anaemia (0.29% per year), c ardiovascular abnormalities (0.13% per year) and vasovagal syncope (0.13% p er year). Conclusions This study demonstrates the importance of medical screening bef ore healthy volunteers participate in clinical research.