Diabetes Screening: Which Patients, What Tests, and How Often?

Article excerpt

Psychiatric patients--especially those with schizophrenia or taking atypical antipsychotics--are at risk for developing type 2 diabetes mellitus (T2DM) and prediabetes conditions. T2DM can be present for years without significant symptoms and even asymptomatic conditions increase the risk of cardiovascular, renal, retinal, and neurologic complications.

Despite a need for T2DM screening and treatment, expert guidelines disagree on who and how to screen (Table 1, page 20). Although testing patients who have diabetes symptoms--including polyuria, polydipsia, and weight loss--is indicated, some medical groups advocate screening asymptomatic persons for T2DM.

Table 1

General population screening recommendations for type 2 diabetes
mellitus or prediabetes

Organization                         Year    Whom to      How to
                                             screen       screen

U.S. Preventive Services Task Force  2008  Asymptomatic   FPG or OGTT
(USPSTF)                                   adults with    every 3
                                           sustained      years
                                           blood
                                           pressure >
                                           135/80 mmHg
                                           (treated or
                                           untreated)

American Diabetes Association        2009  All adults     FPG or
(ADA)                                      age [greater   2-hour OGTT
                                           than or equal  every 3
                                           to]45 Adults   years or
                                           of any age     more
                                           with BMI >25   frequently,
                                           kg/[m.sup.2]   depending on
                                           and [greater   initial
                                           than or equal  results and
                                           to] 1 risk     risks
                                           factors for
                                           diabetes
                                           (Table 2,
                                           page 23)

American Association of Clinical     2007  All adults     FPG or
Endocrinologists (AACE)                    age [greater   2-hour OGTT
                                           than or equal  (frequency
                                           to]30 with     not
                                           risk factors   specified)
                                           for diabetes
                                           (Table 2,
                                           page 23)

European Association for the Study   2007  All adults     OGTT
of Diabetes (EASD) and European            with elevated  (frequency
Society of Cardiology (ESC)                risk score *   not
                                                          indicated)

FPG: fasting plasma glucose; OGTT: oral glucose tolerance test (75 gm
glucose load); BMI: body mass index

* Risk scoring tool available at www.diabetes.fi/english/risktest

Screening recommendations

Consensus guidelines. In 2004, the American Diabetes Association (ADA), American Psychiatric Association (APA), American Association of Clinical Endocrinologists (AACE), and North American Association for the Study of Obesity (NAASO) created consensus guidelines for screening psychiatric patients receiving atypical antipsychotics. In addition to diabetes risk, psychiatric patients are at higher risk for metabolic syndrome, dyslipidemia, obesity, and hypertension. (1). The ADA, APA, AACE, and NAASO recommend regularly screening for weight gain and dyslipidemia, obtaining baseline values of fasting plasma glucose (FPG), rechecking FPG after 3 months, and then screening annually for diabetes or prediabetes. …