Insulin‐treated diabetes: awareness and adherence to driving recommendations

Abstract

Sir, We read with interest the recent article by Ken Shaw, entitled ‘Safe driving on insulin: improving implementation using new technology in glucose monitoring?’ (Pract Diabetes 2014;31[9]:361). Hypoglycaemia and hypoglycaemia unawareness are well-recognised and serious complications of insulin therapy. Hypoglycaemia has a significant negative impact on cognitive function, working memory, spatial awareness and emotional well-being.1-4 All of these parameters are essential for a safe driving performance. Studies have demonstrated that insulin-induced hypoglycaemia was associated with poor driving performance.5 At present in the UK, drivers with insulin-treated diabetes are issued with one- to three-year Group 1 licences or one-year Group 2 licences. The Driver and Vehicle Licensing Agency (DVLA) has published guidance on driving regulations and requirements, including recommendations for safe driving precaution measures, and sent it to these drivers at the time of their licences’ application and renewal.6 Nevertheless, previous studies have shown that patients’ awareness and adherence to DVLA's rules and regulations were poor.7, 8 We recently conducted a short survey to assess whether patients are aware of and follow the guidance. An anonymous questionnaire was given to all insulin-treated diabetes patients, over a three-month period. Patients were eligible if they: were >18 years old; had diabetes treated with insulin; held a current UK driving licence and had been driving. Temporary insulin users, e.g. women with gestational diabetes treated with insulin, were excluded. Patients were asked to fill in the questionnaire prior to the consultation with health care professionals in order to avoid recall bias. A total of 75 patients agreed to take part in the survey; however, only 61 patients completed the questionnaire. Over half of drivers in our cohort were aged 51 and above and nearly one-third were over 61 years of age. This age distribution reflects the proportion of elderly drivers in the National Transport Survey.9 The elderly driver group may need particular attention since increasing age is one of the risk factors for severe hypoglycaemia and hypoglycaemia unawareness. Seventy percent of the patients had type 1 diabetes, 25% type 2 diabetes and 5% other type of diabetes. Seventy-nine percent of patients said that driving is an essential part of their daily life or occupation; 93% of patients recognised symptoms of hypoglycaemia most of the time; 13% of patients had experienced a hypo (either mild or severe) while driving in the last 12 months. Just over 70% (43/61) always carry blood glucose testing kits while driving; 87% of patients always carry quick-acting carbohydrates in the car. Just under half of the patients (49%) always check their blood glucose level before driving. Just over half of the patients (52%) always take a break from a long journey to check blood glucose. Eleven percent of patients did not know the safe blood glucose level to drive and 7% said they would drive even when their blood glucose level is below 5mmol/L. Two would continue to drive even if they start to feel symptoms of hypoglycaemia or their blood glucose is less than 4mmol/L. Only 23% would wait the recommended 45 minutes before driving again after an episode of hypoglycaemia. Eighty-four percent of patients stated that they had received advice about driving and diabetes from health care professionals. Just over half of the patients thought that they have received comprehensive advice about driving and diabetes. Only 11% of patients would like to get more detailed information about DVLA rules and recommendations. Nearly 90% of patients thought that they already have enough information and did not want to seek more information. Ten out of 61 patients stated that they did not receive any form of education about driving and diabetes. Worryingly, nine of these patients did not want to get more information relating to driving and diabetes. The results of our study mirrored the findings of previous studies.7, 8, 10 In our sample of patients, most of them recalled that they have received some information about driving and diabetes. However, there is still considerable room for improvement in their knowledge and adherence to safety recommendations. Health care professionals should be more proactive: discussion about driving rules and recommendations should form part of the routine clinic encounter. A patient information leaflet is a good way of reinforcing what has been discussed during consultation. The results of this study raise questions about the knowledge of the health care professionals who complete DVLA fitness to drive forms concerning the recommendations for safe driving for people with insulin-treated diabetes. Further studies in this area are warranted. We thank all of the staff at the diabetes clinic in Wrexham Maelor Hospital for their assistance in distributing and collecting the questionnaire. There are no conflicts of interest declared. References are available at www.practicaldiabetes.com.