COPENHAGEN—Patients with dementia who have cataract surgery have improved visual acuity and reduced decline in cognitive function, researchers reported at the 2014 Alzheimer’s Association International Conference.
Alan J. Lerner, MD, Director of the Brain Health and Memory Center, Department of Neurology, Case Western Reserve University School of Medicine in Cleveland, and colleagues conducted a systematic analysis of two cohorts of patients who were diagnosed with dementia and visually significant cataracts. An intervention group had cataract surgery after study enrollment and baseline testing. A control group had either refused or delayed cataract surgery until six months had elapsed and they had completed their final outcome testing.
Despite the frequent occurrence of cataracts among patients with dementia, “health care providers are reluctant to proceed with cataract surgery when visually indicated because of concerns regarding complications,” noted Dr. Lerner.
All subjects met the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer’s Disease and Related Disorders Association criteria for Alzheimer’s disease (n = 26) or other neurodegenerative dementias (n = 16) and had at least one “visually significant cataractous lens,” according to Dr. Lerner.
Participants were tested at baseline and at six months for visual acuity (using the Early Treatment Diabetic Retinopathy Study [ETDRS] chart), cataract severity, and cognitive status (using the Mini-Mental State Examination [MMSE] and Alzheimer’s Disease Assessment Scale–Cognitive Subscale). The researchers also assessed patients’ neuropsychiatric symptoms and caregivers’ distress using the Neuropsychiatry Inventory. In addition, the investigators used t-tests to compare mean changes in the intervention group with those in the control group.
Intervention group members had a mean age of 80; 61% were women, and 39% were ethnic minorities. Control participants had a mean age of 83.6; 79% were women, and 43% were ethnic minorities.
Patients who had cataract surgery had significant improvement in visual acuity, compared with the controls, as assessed by the Snellen-equivalent ETDRS far acuity measure. The intervention group also improved in binocular reading acuity, and the controls had no such improvement.
“The intervention after six months led to improvement in MMSE of 0.39 points, while the control group declined by 2.31 points,” stated Dr. Lerner. In addition, the intervention group had reduced neuropsychiatric symptoms, while the control group “presented with more symptoms and an increase in reported symptoms after six months,” he added.
The intervention group also had reduced caregiver distress. In contrast, the control group’s caregivers presented with and maintained more distress.
“The findings suggest the need to aggressively address dementia comorbidities such as cataract-related visual impairment, while balancing safety and medical risks,” concluded Dr. Lerner.
—Colby Stong