Bilateral cataracts in a young patient with bipolar disorder on treatment with risperidone

To the Editor

Patients with mental illness are at an elevated risk of developing cataracts when compared to the general population. This effect is multifactorial and corresponds to higher rates of smoking, alcohol use disorder and hypertension (Souza et al., 2008). There is evidence that first-generation antipsychotics increase the risk of cataracts; however, data about second-generation antipsychotics are limited and consist mainly of case reports involving quetiapine (Laties et al., 2015; Souza et al., 2008). There is only one case report associating risperidone with cataracts (Dsouza, 2015), in addition to one large-scale study comparing the cataractogenic potential of quetiapine versus risperidone (Laties et al., 2015). Our goal is to add to the current evidence base by reporting a case of an otherwise healthy young individual who developed cataracts while on risperidone.

O.D. is a 27-year-old male, with no medical comorbidities, who has a diagnosis of attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder. Since age 10, the patient was treated with methylphenidate and valproic acid; however, at the age of 16, he started displaying symptoms of psychosis. After a failed trial of quetiapine 400 mg/day for a few months, the patient was put on risperidone 6mg /day. At the same time, valproic acid and methylphenidate were discontinued, and lithium 900 mg/day was initiated with good response.

The patient first complained of blurry vision at age 26 and saw an optometrist who discovered cataracts in both eyes with 20/40 vision. The patient’s last recorded vision was 20/20 documented at age 24. The patient was referred to an ophthalmologist, who diagnosed grade 3 cataracts of the left eye and trace cataracts of the right eye, indicating bilateral asymmetrical cataracts. Given ongoing blurry vision, he opted for cataract surgery of the left eye. A later eye examination revealed no further changes in the right eye cataract.

To our knowledge, this is the second case showing a potential association between cataracts and risperidone. Our patient has a lack of risk factors including no metabolic abnormalities, a normal baseline eye examination and no prior history of cataracts. Although the patient was exposed to quetiapine and valproic acid, the exposure to those medications was for shorter periods of time. Moreover, the patient had an unremarkable eye examination several years after discontinuing quetiapine and valproic acid. Given that there are no reports indicating a relationship between lithium and cataract formation, we suggest that risperidone has contributed to the patient’s cataract formation.