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Diabetes and DrivingAMERICAN DIABETES ASSOCIATION

Of the nearly 19 million people in theU.S. with diagnosed diabetes (1), alarge percentage will seek or cur-

rently hold a license to drive. For many, adriver’s license is essential to work; takingcare of family; securing accessto public andprivate facilities, services, and institutions;interacting with friends; attending classes;and/or performing manyother functions of daily life. Indeed, in many communitiesand areas of the U.S. the use of an automo-bile is the only (or the only feasible or af-fordable) meansof transportation available.

There has been considerable debatewhether, and the extent to which, diabetesmay be a relevant factor in determiningdriver ability and eligibility for a license.This position statement addresses suchissues in light of current scientic andmedical evidence.

Sometimes people with a strong in-terest in road safety, including motor vehi-cle administrators, pedestrians, drivers,other road users, and employers, associateall diabetes with unsafe driving when infact most people with diabetes safely oper-ate motor vehicles without creating any

meaningful risk of injury to themselvesor others. When legitimate questions ariseabout the medical tness of a person withdiabetes to drive,an individual assessment of that person’s diabetes managementdwithparticular emphasis on demonstrated abil-ity to detect and appropriately treat poten-tial hypoglycemiadis necessary in orderto determine any appropriate restrictions.The diagnosis of diabetes is not suf cientto make any judgments about individualdriver capacity.

This document provides an overview

of existing licensing rules for people withdiabetes, addresses the factors that impactdriving for this population, and identiesgeneral guidelines for assessing driver t-ness and determining appropriate licensingrestrictions.

LICENSINGREQUIREMENTSdPeople with dia-betes are currently subject to a great variety of licensing requirements and restrictions.These licensing decisions occur at severalpoints and involve different levels andtypes of review, depending on the type of driving. Some states and local jurisdictionsimpose no special requirements for peoplewith diabetes. Other jurisdictions ask driv-ers with diabetes various questions abouttheir condition, including their manage-ment regimen and whether they have ex-

perienced any diabetes-related problemsthat could affect their ability to safely oper-ate a motor vehicle. In some instances,answers to these questions result in restric-tions being placed on a person’s license, in-cluding restrictions on the type of vehiclethey may operate and/or where they may op-erate that vehicle. In addition, the rules foroperating a commercial motor vehicle, andfor obtaining related license endorsements(such asrulesrestrictingoperationof a schoolbus or transport of passengers or hazardousmaterials) are quite different and in many ways more cumbersome for people with di-

abetes, especially those who use insulin. With the exception of commercial

driving in interstate commerce (Interstatecommercial driving is dened as trade,traf c or transportation in the United Statesbetween a place in a state and a placeoutside of such a state, between two placesin a state through another state or a placeoutside of the United States, or betweentwo places in a state as part of trade, traf cor transportation originating or terminat-ing outside the state or the United States[2]), which is subject to uniform federal

regulation, both private and commercialdriving are subject to rules determined by individual states. These rules vary widely,with each state taking its own approach todetermining medical tness to drive andthe issuance of licenses. How diabetes is

identied,which peopleare medically eval-uated, and what restrictions are placed onpeople who have experienced hypoglyce-mia or other problems related to diabetes

all vary from state to state.States identify drivers with diabetes

in a number of ways. In at least 23 states,drivers are either asked directly if they have diabetes or are otherwise required toself-identify if they have diabetes. In otherstates drivers areasked some variation of aquestion about whether they have a con-dition that is likely to cause altered percep-tion or loss of consciousness while driving.In most states, when the answer to eitherquestion is yes, the driver is required tosubmit to a medical evaluation before heor she will be issued a license.

Medical evaluationDrivers whose medical conditions can leadto signicantly impaired consciousness areevaluated for their tness to continue todrive. For people with diabetes, this typi-cally occurs when a person hasexperiencedhypoglycemia (3) behind the wheel, even if this did not result in a motor vehicle acci-dent. In some states this occurs as a resultof a policy to evaluate all people with di-abetes, even if there has been no triggeringevent. It can also occur when a person ex-

periences severe hypoglycemia while notdriving and a physician reports the episodeto the licensing authority. In a handful of states, such reporting by physicians is man-datory. In most other states physicians arepermitted to make reports but are givendiscretion to determine when such reportsare necessary. Some states specify thatphysiciansmay voluntarilyreport those pa-tients who pose an imminent threat to pub-lic safety because they are driving againstmedical advice. Physicians and others re-quired to make reports to the licensing au-thorityare usually provided withimmunity from civil and criminal actions resultingfrom the report.

When licensing aut horities learnthat a driver has experienced an episodeof hypoglycemia that potentially affectedthe ability to drive, that driver is referredfor a medical evaluation and in many cases will lose driving privileges for a periodof time until cleared by the licensing au-thority. This period can range from 3 to 6months or longer. Some state laws allow forwaivers of the rules when the episode is aone-time event not likely to recur, for

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Peer reviewed by the Professional Practice Committee, September 2011, and approved by the ExecutiveCommittee of the American Diabetes Association, November 2011.

DOI: 10.2337/dc12-s081© 2012 by the American Diabetes Association. Readers may use this article as long as the work is properly

cited,theuse iseducationaland notforprot, andthe work is notaltered. See http://creativecommons.org/ licenses/by-nc-nd/3.0/ for details.

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example because of a change in medicationor episodes that occur only during sleep.

Medical evaluation procedures vary and range from a simple conrmation of the person’s diabetes from a physicianto amore elaborate process involving a statemedical advisory board, hearings, andpresentation and assessment of medical

evidence. Some states convene medicaladvisory boards with nurses and physi-cians of different specialties who review and make recommendations concerningthe licensing of people with diabetes andother medical conditions. In other states,licensing decisions are made by adminis-trative staff with little or no medical train-ing and with little or no review by amedical review board or by a physicianor physicians with any relevant expertiseconcerning medical conditions presentedby individual applicants.

The medical evaluation process forcommercial drivers occurs at predeter-mined intervals, typically every 2 years.Unlike noncommercial licenses, theseregular evaluations are not linked toepisodes of severe hypoglycemia but arepart of an ongoing tness evaluation for

jobs requiring commercial driving. The fed-eral government has no diabetes-specicrestrictions for individuals who managetheir disease with diet, exercise, and/ororal medication. It offers an exemptionprogram for insulin-using interstate com-mercial drivers and issues medical certi-

cates to qualied drivers. Factors in thefederal commercial driving medical evalu-ation include a review of diabetes history,medications, hospitalizations, blood glu-cose history, and tests for various com-plications and an assessment of driverunderstanding of diabetes and willingnessto monitor their condition.

SCIENCE OF DIABETES ANDDRIVINGdHypoglycemia indicatingan impaired ability to drive, retinopathy or cataract formation impairing the visionneeded to operate a motor vehicle, andneuropathy affecting the ability to feel footpetals can each impact driving safety (4).However, the incidence of these conditionsis not suf ciently extensive to justify re-striction of driving privileges for all driverswith diabetes. Driving mishaps related todiabetes are relatively infrequent for mostdrivers with diabetes and occur at a lowerrate than mishaps of many other driverswith conditions that affect driving perfor-mance and that are tolerated by society.

However, just as there are some pa-tients with conditions that increase their

risk of incurring driving mishaps, such asunstable coronary heart disease, obstruc-tive sleep apnea, epilepsy, Parkinson ’sdisease, or alcohol and substance abuse,there are also some drivers with diabetesthat have a higher risk for driving mis-haps. The challenges are to identify high-risk individuals and develop measures to

assist them to lower their risk for drivingmishaps.

Understanding the risk of diabetesand driving In a recent Scottish study, only 62% of health care professionals suggested thatinsulin-treated drivers should test theirblood glucose before driving; 13% of healthcare professionals thought it safe to drivewith blood glucose,72 mg/dL (4 mmol/L),and 8% did not know that impaired aware-ness of hypoglycemia might be a contrain-dication to driving (5). It is important thathealth care professionals be knowledgeableand take the lead in discussing risk reduc-tion for their patients at risk for hypoglyce-mia. In a large international study, nearly half of drivers with type 1 diabetes andthree-quarters of those with type 2 diabeteshad never discussed driving guidelines withtheir physician (8).

A meta-analysis of 15 studies sug-gested that the relative risk of having amotor vehicle accident for people withdiabetes as a whole, i.e., without differen-tiating those with a signicant risk from

those with little or no risk, as comparedwith the general population ranges be-tween 1.126 and 1.19, a 12–19% in-creased risk (6). Some published studiesindicated that drivers with type 1 diabeteshave a slightly higher risk, with a relativerisk ratio of ;2 (7,8,9), but this was notconrmed by other studies (10). Two stud-ies even suggested that there is no increasedrisk associated with insulin-treated diabe-tes (11,12), but the methodologies usedhave been criticized (13).

This increased risk of collisions mustbe interpreted in the light of society ’s tol-erance of other and much higher–riskconditions. For example, 16-year-oldmales have 42 times more collisions than35- to 45-year-old women. If the heaviestcar collides with the lightest car, the driverof the latter is 20 times more likely to bekilled than the driver of the former. Themost dangerous rural highways are 9.2times more dangerous than the safest urbanhighways. Driving at 1:00 A.M. on Sunday is142 times more dangerous than driving at11:00 A.M. (7). Drivers with attention decit/ hyperactivity disorder have a relative risk

ratio of ;4 (14), whereas those with sleepapnea have a relative risk of ;2.4 (15). If society tolerates these conditions, it wouldbe unjustied to restrict the driving priv-ileges of an entire class of individuals whoare at much lower risk, such as driverswith diabetes.

The most signicant subgroup of

persons with diabetes for whom a greaterdegree of restrictions is often applied isdrivers managing their diabetes with in-sulin. Yet, when the type of diabetes iscontrolled for, insulin therapy per se hasnot been found to be associated with in-creased driving risk (3,16,17). While im-paired awareness of hypoglycemia hasbeen found to relate to increased incidenceof motor vehicle crashes in some studies(12), it has not been found to be a relevantvariable in other studies (4,7,23). The sin-gle most signicant factor associated withdriving collisions for drivers with diabetesappears to be a recent history of severe hy-poglycemia, regardless of the type of diabe-tes or the treatment used (1,3,18–21).

The American Diabetes Association Workgroup on Hypoglycemia dened se-vere hypoglycemia as low blood glucoseresulting in neuroglycopenia that disruptscognitive motor function and requires theassistance of another to actively administercarbohydrate, glucagon, or other resuscita-tive actions (22). In a prospective multicen-ter study of 452 drivers with type 1 diabetesfollowed monthly for 12 months, 185 par-

ticipants (41%) reported a total of 503 epi-sodes of moderate hypoglycemia (wherethe driver could still treat him/herself butcould no longer drive safely) and 23 partic-ipants (5%) reported 31 episodes of severehypoglycemia (where the driver was unableto treat him/herself) while driving (21).Conversely, the DiabetesControl and Com-plications Trial (DCCT) group reported 11motor vehicle accidents in 714 episodes of severe hypoglycemia, a rate of 1.5% (23).

The signicant impact of moderatehypoglycemia while driving is supportedby multiple studies demonstrating thatmoderate hypoglycemia signicantly andconsistently impairs driving safety (24–26)andjudgment(27,28) as to whether to con-tinue to drive or to self-treat (29,30) undersuch metabolic conditions. In one study,25% of respondents thought it was safe todrive even when blood glucose was ,70mg/dL (3.9 mmol/L) (31).

While signicant hyperglycemia may impair cognitive, motor, and perceptualfunctioning (32–35), there is only one re-port suggesting extreme hyperglycemiacan impact driving safety (36). Thus,

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efforts to equate hyperglycemia with driv-ing impairment are currently not scientif-ically justied.

Individual differencesEighty percent of episodes of severe hy-poglycemia affect about 20% of peoplewith type 1 diabetes (37–39). Available

data suggest that a smallsubgroup of driv-ers with type 1 diabetes account for themajority of hypoglycemia-related colli-sions (9,30,40). When 452 drivers withtype 1 diabetes were followed prospec-tively for a year, baseline reports of priorepisodes of mild symptomatic hypoglyce-mia while driving or severe hypoglycemiawhile driving, hypoglycemia-related driv-ing mishaps, or hypoglycemia-relatedcollisions were associated with a higherrisk of driving mishaps in the following12 months by 3, 6, 6, and 20%, respec-tively. Risk increased exponentially withadditional reported episodes: If individu-als had two episodes of severe hypoglyce-mia in the preceding 12 months their riskincreased to 12%, and two collisions inthe previous 2 years increased their riskby 40%. The strongest predictors in-volved a history of hypoglycemia whiledriving(21). Laboratory studies that com-pared drivers with type 1 diabetes whohad no history of hypoglycemia-relateddriving mishap in the past year to thosewho had more than one mishap foundthat those with a history of mishaps: 1)

drove signicantly worse during progres-sive mild hypoglycemia (70–50 mg/dL,3.9–2.8 mmol/L) but drove equally wellwhen blood glucose was normal (euglyce-mia); 2) had a lower epinephrine responsewhile driving during hypoglycemia, 3)were more insulin sensitive, and 4) demon-strated greater dif culties with workingmemory and information processing speedduring euglycemia and hypoglycemia(24,40,41). Thus, a history of mishapsshould be used as a basis for identifyinginsulin-managed drivers with elevatedrisk of future mishaps. Such individualsare appropriately subjected to additionalscreening requirements.

Four studies have demonstrated thatBlood Glucose Awareness Training(BGAT) reduces the occurrence of colli-sions and moving vehicle violations whileimproving judgment about whether todrive while hypoglycemic (42–45). BGATis an 8-week psycho-educational trainingprogram designed to assist individualswith type 1 diabetes to better anticipate,prevent, recognize, and treat extremeblood glucose events. This intervention

can be effectively delivered over the inter-net (46). Diabetes Driving (diabetesdriv-ing.com), a program funded by theNational Institutes of Health, is anotherinternet-based tool to help assess therisk of driving mishaps and assist high-risk drivers to avoid hypoglycemia whiledriving and to better detect and manage

hypoglycemia if it occurs while driving.

RECOMMENDATIONS

Identifying and evaluating diabetesin driversIndividuals whose diabetes poses a sig-nicantly elevated risk to safe drivingmust be identied and evaluated prior togetting behind the wheel. Because peoplewith diabetes are diverse in terms of thenature of their condition, the symptomsthey experience, and the measures they take to manage their diabetes, it is impor-tant that identication and evaluation pro-cesses be appropriate, individualized, andbased not solely on a diagnosis of diabetesbut rather on concrete evidence of actualrisk. Laws that require all people withdiabetes (or all people with insulin-treateddiabetes) to be medically evaluated as acondition of licensure are ill advised be-cause they combine people with diabetesinto one group rather than identifyingthose drivers who may be at increased riskdue to potential dif culties in avoidinghypoglycemia or the presence of compli-

cations. In addition, the logistics of regis-tering and evaluating millions of peoplewith diabetes who wish to drive presentsan enormous administrative and scal bur-den to licensing agencies. States that requiredrivers to identify diabetes should limitthe identication to reports of diabetes-related problems.

To identify potentially at-risk drivers, ashort questionnaire can be used to ndthose drivers who may require furtherevaluation. The questionnaire should askwhether the driver has, within the past 12months, lost consciousness due to hypo-glycemia, experienced hypoglycemia thatrequired intervention from another per-son to treat or that interfered with driving,or experienced hypoglycemia that devel-oped without warning. The questionnaireshould also query about loss of visualacuity or peripheral vision and loss of feeling in the right foot. Inasmuch asobstructive sleep apnea is more commonin people with type 2 diabetes than in thenondiabetic population, patients shouldbe queried about falling asleep during theday. Any positive answer should trigger an

evaluation to determine whether restric-tions on the license or mechanical mod-ications to the vehicle (e.g., handcontrols for people with an insensatefoot) are necessary to ensure public safety.It is ill-advised to determine risk fordriving mishaps based on a driver’s gly-cosylated hemoglobin because episodic

transitions into hypoglycemia, not averageblood glucose, increases risk of drivingmishaps.

Evaluation of drivers with diabetesmust include an assessment by the treat-ing physician or another diabetes special-ist who can review recent diabetes history and provide to the licensing agency arecommendation about whether thedriver has a condition that impairs hisor her ability to safely operate a motorvehicle. The treating physician or anotherphysician who is knowledgeable aboutdiabetes is the best source of informationconcerning the driver’s diabetes manage-ment and history. The input of such aphysician is essential to assess a person’sdiabetes management and determinewhether operation of a motor vehicle issafe and practicable. If questions ariseconcerning the safe driving ability of aperson with chronic complications of di-abetes (e.g., retinopathy or neuropathy),the individual should be referred to a spe-cialist with expertise in evaluating thediabetes-related problem for specic rec-ommendations.

Physicians should be requested toprovide the following information: 1)whether the driver has had an episode of severe hypoglycemia requiring interven-tion from another person within the pre-vious 2 years (and when this happened);

2) whether there was an explanation forthe hypoglycemia; 3) whether thedriver isat increased risk of severe hypoglycemia;4) whether the driver has the ability torecognize incipient hypoglycemia andknows how to take appropriate correctiveaction; 5) whether the driver provides ev-idence of suf cient self-monitoring of blood glucose; 6) whether the driver hasany diabetes-related complications affect-ing safe driving that need further assess-ment; and 7) whether the driver has agood understanding of diabetes and itstreatment, has been educated on theavoidance of hypoglycemia while driving,and is willing to follow a suggested treat-ment plan.

Whenevaluatinga driverwith a history of severe hypoglycemia, impaired hypogly-cemia awareness, or a diabetes-related mo-tor vehicle accident, it is necessary to


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investigate the reasons for the hypoglyce-mia and to determine whether it is afunction of the driver’s treatment regimenor lifestyle, a psychological reaction to themanagement of their diabetes, or the nor-mal course of diabetes. Appropriate clini-cal interventions should be instituted.

Licensing decisions following evaluationDrivers with diabetes should only have alicense suspended or restricted if doing sois the only practical way to address anestablished safety risk. Licensing deci-sions should reect deference to the pro-fessional judgment of the evaluatingphysician with regard to diabetes, whilealso balancing the licensing agency ’s needto keep the roads and the public safe.States should have medical advisory boards whose role is to assess potentialdriving risks based on continually up-dated medical information, to ensurethat licensing agency staff is prepared tohandle diabetes licensing issues, and tomake recommendations relevant to indi-vidual drivers. State medical advisory boards should have representation by health care professionals with expertisein treating diabetes, in addition to the in-formation provided by thedriver’s treatingphysician, prior to making licensing deci-sions for people with diabetes. Where themedical advisory board does not have apermanent member with expertise in di-

abetes, such an expert shouldbe consultedin cases involving restrictions on a driverwith diabetes.

As discussed above, a history of hy-poglycemia does not mean an individualcannot be a safe driver. Rather, whenthere is evidence of a history of severehypoglycemia, an appropriate evaluationshould be undertaken to determine thecause of the low blood glucose, the cir-cumstances of the episode, whether it wasan isolated incident, whether adjustmentto the insulin regimen may mitigate therisk, and the likelihood of such an episoderecurring. It is important that licensingdecisions take into consideration contrib-utory factors that may mitigate a potentialrisk, and that licensing agencies do notadopt a “one strike” approach to licensingpeople with diabetes. Drivers with diabe-tes must be individually assessed to deter-mine whether their diabetes poses a safety risk. The mere fact that a person’s diabeteshas come to the attention of the licensingagency dwhether by a report or becauseof an accidentdshould not itself pre-determine a licensing decision.

Generally, severe hypoglycemia thatoccurs during sleep should not disqualify a person from driving. Hypoglycemia thatoccurswhile thepersonis notdriving shouldbe examined to determine if it is indicativeof a larger problem or an event that is notlikely to recur while the person is behindthe wheel of a car (e.g., hypoglycemia that

occurs during an intense bout of exercise).Some episodes of severe hypoglycemia canbe explained and corrected with the assis-tance of a diabetes health care professional,e.g., episodes that occur because of achange in medication. However, recurrentepisodes of severe hypoglycemia, denedas two or more episodes in a year, may indicate that a person is not able to safely operate a motor vehicle.

States whose licensing rules lead to asuspension of a driver’s license followingan episode of hypoglycemia should allow for waiver of these rules when the hypo-glycemia can be explained and addressedby the treating physician and is not likely to recur. For example, waivers may be ap-propriate following hypoglycemia thathappens as a result of a change in medi-cation or during or concurrent with ill-ness or pregnancy. Licensing agenciesmay request documentation from thephysician attesting that the patient meetsthe conditions for a waiver (which may include, among other requirements, edu-cation on diabetes management andavoidance of hypoglycemia).

Drivers with a suspended license be-cause of factors related to diabetes shouldbe eligible to have their driver’s license re-instated following a suf cient period of time (usually no more than 6 months)upon advice from the treating physicianthat the driver has made appropriate ad-

justments and is adhering to a regimenthat has resulted in correction of the prob-lems that led to the license suspension. Fol-lowing reinstatement of driving privileges,periodic follow-up evaluation is necessary to ensure that the person remains safely able to operate a motor vehicle.

People who experience progressiveimpairment of their awareness of hypo-glycemia should consult a health careprovider to determine whether it is safeto continue driving with proper measuresto avoid disruptive hypoglycemia (such astesting blood glucose before driving andat regular intervals in the course of a

journey lasting more than 30–60 min). If the driver is able to make adjustments toimprove awareness or prevent disruptivehypoglycemia while driving, there shouldnot be license restrictions. Continuous

glucose monitoring may also be benecial,particularly when noting the direction of the glucose trend. If this technology isused, the person using the device needsto appreciate that any action taken (e.g.,additional carbohydrate consumption)needs to be based on a blood glucose mea-surement.

The determination of which disquali-ed drivers should be reevaluated andwhen this should be done should be madeon an individual basis considering factorssuch as the circumstances of the disqual-ifying event and changes in medicationand behavior that havebeen implementedby the driver. When an assessment deter-mines that the driver should be evaluatedat some point in the future, the driver’sphysician should be consulted to deter-mine the length of the reevaluation pe-riod. A driver with diabetes should notbe kept in an endless cycle of reevaluationif there is no longer a signicantly ele-vated safety risk.

The determination of medical tnessto drive should be a clinical one, weighingthe various factors noted above. Decisionsabout whether licensing restrictions arenecessary to ensure safety of the travelingpublic are ultimately determined by thelicensing agency, taking into account theclinical determination of medical tness.

Physician reporting Although the concept behind mandatory

physician reporting laws is to keep roadssafe by eliminating unacceptable riskfrom impaired driving, such laws havethe unintended consequence of discour-aging people with diabetes from discus-sing their condition frankly with aphysician when there is a problem thatneeds correction due to fear of losing theirlicense. Patients who are not candid withtheir physicians are likely to receive in-ferior treatment and therefore may expe-rience complications that present adriving risk. In addition to the negativeeffect that mandatory reporting has on thephysician-patient relationship, there isno evidence that mandatory physicianreporting reduces the crash rate or im-proves public safety (47).

Physicians should be permitted toexercise professional judgment in decid-ing whether and when to report a patientto the licensing agency for review of driving privileges. States that allow physi-cians to make such reports should focuson whether the driver’s mentalor physicalcondition impairs the patient’s ability toexercise safe control over a motor vehicle.


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Reports based solely on a diagnosis of di-abetes, or tied to a characterization thatthe driver has a condition involving lapsesof consciousness, are too broad and donot adequately measure individual risk.Ultimately, reports must be left to the dis-cretion of the physician, using profes-sional judgment about whether the

patient poses a safety risk. Further, in or-der to protect the physician-patient rela-tionship and ensure the open and honestcommunication that ultimately promotessafety, it is important that physicians beimmunized from liability, both for mak-ing reports and not making reports.

Patient education and clinicalinterventionsIt is important that health care professio-nals be knowledgeable and take the lead indiscussing risk reduction for their patientsat risk for disruptive hypoglycemia. Thisstarts with health care professionals beingconversant with safe practices, particularly for those patients at increased risk fordiabetes-related incidents. Perhaps themost important aspect of encouraging peo-ple with diabetes to be safe drivers is forhealth care professionals who treat diabeticdrivers to provide education about drivingwith diabetes and potential risks associatedwith patients’ treatment regimens. Whenthat regimen includes the possibility of hy-poglycemia, education should include in-struction on avoiding and responding to

hypoglycemia, discussion about the pa-tient’s vulnerability for driving mishaps,and ongoing learning to ensure that pa-tients have knowledge of when it is and isnot safe for them to drive. For example, therisks of driving under the inuence of alco-hol are well known, but the delayed hypo-glycemic effects of even moderate alcoholintake are not, and alcohol exacerbates thecognitive impairment associated with hy-poglycemia (48). Inasmuch as hypoglyce-mia can be mistaken for intoxication, andboth increase the risk of motor vehicle ac-cidents, patients should be counseled totest glucose more frequently for severalhours after moderate alcohol intake.

When a patient has complications of dia-betes, it is important for the physician todiscuss with the driver the effect of thosecomplications, if any, on driving ability.

Physicians and other health care pro-fessionals who treat people with diabetesshould regularly discuss the risk of drivingwith low blood glucose with their patients.Clinical visits should include review of blood glucose logs and questions to thepatient about symptoms associated with

high or low blood glucose levels and whatthe patient did to treat those levels. Allow-ing health care professionals to exerciseprofessional judgment about the informa-tion they learn in these patient conversa-tions will encourage candid sharing of information and lead to improved patienthealth and road safety.

Clinical interventions in response tohypoglycemia vary by individual but may include strategies for the frequency andtiming of blood glucose monitoring,medication dosage changes, and estab-lishing more conservative glucose targetsif there is a history of severe hypo-glycemia. Certain people who have ahistory of severe hypoglycemia may beencouraged by their health care providerto use continuous glucose monitoringsystems that enable them to detect atrend toward hypoglycemia before glu-cose levels fall to a level that will affectsafe driving.

Of note, special care should be taken toprevent hypoglycemia while operating any vehicle in drivers with type 1 diabetes and inthose with type2 diabeteswho are at risk fordeveloping hypoglycemia. They should beinstructed to always check blood glucosebefore getting behind the wheel and atregular intervals while driving for periodsof 1 h or greater. Consideration should begiven to factors that may predict a fall inblood glucose, including time of insulinadministration, timing of the last meal or

food ingestion, and exercise type, duration,intensity, and timing. Low blood glucosevalues should be treated immediately andappropriately, and the driver should notdrive until blood glucose is in a safely acceptable range, usually after 30–60min because of delayed recovery of cog-nitive function.

People with diabetes who are at riskfor disruptive hypoglycemia should becounseled to: 1) always carry a blood glu-cose meter and appropriate snacks,including a quick-acting source of sugar(such as juice, nondiet soda, hard candy,or dextrose tablets) as well as snacks withcomplex carbohydrate, fat, and protein(e.g., cheese crackers), in their vehicle;

2) never begin an extended drive withlow normal blood glucose (e.g., 70–90mg/dL) without prophylactic carbohy-drate consumption to avoid a fall in bloodglucose during the drive; 3) stop the ve-hicle as soon any of the symptoms of low blood glucose are experienced and mea-sure and treat theblood glucose level; and4) not resume driving until their bloodglucose and cognition have recovered.

CONCLUSIONdIn summary, peoplewith diabetes should be assessed individ-ually, taking into account each individu-al’s medical history as well as the potentialrelated risks associated with driving.

AcknowledgmentsdThe American Diabetes

Association thanks the members of the writinggroup for developing this statement: DanielLorber, MD, FACP, CDE (Chair);JohnAnderson,MD;ShereenArent,JD; DanielJ. Cox, PhD, ABPP;Brian M. Frier, BSc,MD, FRCPE, FRCPG; Michael A. Greene, JD; John W. Grif n, Jr., JD; Gary Gross, JD; Katie Hathaway, JD; Irl Hirsch, MD;Daniel B. Kohrman, JD; David G. Marrero, PhD;Thomas J. Songer, PhD; and Alan L. Yatvin, JD.

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full diabetes and driving

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