To the Editor: In his Grand Rounds, Dr Durso1 discussed clinical guidelines for care of older persons with diabetes mellitus. His argument is compelling: frail older individuals with a shorter life expectancy may have different therapeutic benefits compared with younger, healthier populations. This is likely to be relevant to a substantial proportion of individuals with diabetes. In the United Kingdom, half of the individuals with diabetes are older than 65 years and a quarter are aged 75 years or older.2 However, most clinical evidence is from studies of middle-aged persons. Frail older persons are generally excluded from published clinical trials, reflecting both publication bias and the unjustified exclusion of older adults from study protocols.3 Thus, we do not know how much older patients with diabetes might (or might not) benefit from treatment. When seeking patients' opinions, we are further challenged by caring for persons who may not be competent to decide due to cognitive impairment or dementia.