Tobacco Use and Cataracts in Patients With Schizophrenia

To the Editor: Although implementing many of the specific suggestions of Dr. Marder et al. for expanding the health monitoring of patients with schizophrenia could prove useful, the recommendation for biannual (for patients under age 40) or annual (for patients age 40 or older) slit-lamp examinations is not supported by the evidence. The authors acknowledged that evidence for a relationship between cataracts and specific antipsychotics is, unlike every other issue addressed, insufficient for them to assess the quality of the evidence. They acknowledge that only beagles—and not other species, including primates—had an increased risk of cataracts when they received four times the maximum recommended human dose of quetiapine. The United Kingdom epidemiological study that they cited (1) showed no increase in cataracts among a large population treated with antipsychotics, and they cited another naturalistic survey (2) in the United States that reported only 34 lens opacities in 620,000 patient exposures to quetiapine. Given the prevalence—at least 15%—of age-related cataracts in the adult population (3, 4), that study would suggest, if anything, a protective effect of quetiapine.

Although it would certainly be a good practice for psychiatrists to inquire about visual changes in this often-underserved population, requiring at least annual slit-lamp examinations seems ill founded. My informal survey of three sources (university clinic, private ophthalmologist, private optometrist) revealed costs ranging from $110 to $195 for an initial assessment, far more than the authors’ estimate of $23 for an examination. And what is one to do when a lens opacity is found in a patient who may already, by virtue of diabetes, hypertension, nutrition, or age, be at a higher risk for cataracts? If the patient is otherwise responding well to a particular atypical antipsychotic medication, it would seem risky to change it. Despite the authors’ disclaimer that their recommendations should not “subject [providers] to legal consequences,” it is likely that enterprising attorneys will indeed seize upon the opportunity to sue psychiatrists for failure to have ensured one or two slit-lamp examinations per year in a schizophrenic patient who develops a cataract. Why make such a recommendation when the evidence for it is, as the authors acknowledge, absent?