A pilot study of a prospective study of the frequency of hypoglycaemic episodes in insulin-treated diabetics, and the relationship of episodes to employment

Little is known about the relationship between hypoglycaemic episodes in insulin-treated diabetes, and the circumstances of the workplace. There is concern that the mere fact of being diabetic should not prejudice the employment status of the person. There is also a shortage of data to answer the questions of whether hypoglycaemic episodes occur more or less frequently at work than during non-working hours, and whether such episodes have implications for safety in the workplace.We believe that a study is needed, in insulin-treated diabetic people, which will investigate the relative frequency of hypoglycaemic episodes at work and elsewhere, and the relationship of these episodes to individual characteristics. Such a study could recruit subjects, men and women who are in employment, from a diabetic clinic such as that at the Royal Infirmary, Edinburgh, to record details of every hypoglycaemic episode which they experience, over a period of twelve months.This pilot study has developed and tested the instruments and procedures for such a study. These include: a procedure for recruitment based in the Diabetic Clinic at the Royal Infirmary, Edinburgh; a recruitment questionnaire to collect relevant background information including details of occupation and diabetes; a procedure to allow collection of details of every hypoglycaemic episode participants experience over a period of twelve months; and a form on which to record the details of each episode of hypoglycaemia.A procedure was developed to recruit participants from the Diabetic Clinic at the Royal Infirmary, Edinburgh. The procedure works well running in parallel with the routine clinics. To be able to recruit 500 participants to a main study we recommend employment of a full-time research nurse. The clinic is large enough to allow recruitment of such a number over a period of about six months. Recruitment was by informed consent. Participants were assured that the information they provided would be kept in strict confidence.A recruitment questionnaire to collect background information was developed and tested on seventy three insulin-treated diabetic subjects in employment. The recruitment questionnaire was generally well received and well understood apart from one question which needs to be reviewed. A few other minor points were identified which, if reviewed, may lead to further refinement of the questionnaire. A system was developed for participants to report on a monthly basis. A week before an allocated reporting date a reminder is posted to the participant. If no response is received by one week after the reporting date a telephone reminder is made. This system worked well with an 88% response rate in the first month and 84% in the second month. We believe that a good response rate could be maintained for a year because of the initial personal contact with the research nurse in the Diabetic Clinic, the continuing monthly contact and the user friendliness of the hypoglycaemic episode recording form and the reporting system.A form was developed for participants to record the details of each hypoglycaemic episode they experienced during the study period. Nineteen participants completed this form to record details of forty one hypoglycaemic episodes. A section was included for an observer to complete. This was found to be particularly useful for records of severe hypoglycaemic episodes, because 30% of participants found recall of details more difficult after a severe episode. The recording form was generally found to be effective.Of the forty one hypoglycaemic episodes, thirty three (80%) occurred away from work, mostly at home. Twelve (92%) of the severe episodes occurred away from work. The numbers are small but suggest that hypoglycaemic episodes occur less frequently at work than at home or elsewhere.We conclude that the instruments and procedures which have been developed and tested, are effective. We propose that they should, with minor changes, be used for a main study to determine: the frequency of mild and severe hypoglycaemic episodes in insulin-treated subjects who are in employment; the frequency of such episodes which occur at work; the frequency with which hypoglycaemic episodes at work or elsewhere result in injury or accident; and to relate these frequencies to characteristics both of the individual subjects and their diabetic conditions. We believe that such a study is important and could have an impact on the employment of people with insulin-treated diabetes in the future.