COPENHAGEN, Denmark — Cataract surgery may reduce the rate of cognitive decline and improve vision, cognition, and quality of life in dementia patients, new research suggests.
Preliminary results from an ongoing prospective study conducted by investigators at Case Western University in Cleveland, Ohio, showed that in a cohort of patients with dementia and clinically significant cataracts, immediate cataract surgery improved visual acuity, visual quality of life, and behavioral symptoms. It also appeared to slow the rate of cognitive decline, decrease neuropsychiatric symptoms, and reduce caregiver stress.
"Patients who had immediate surgery maintained their MMSE [Mini–Mental State Examination] scores, whereas the delayed group went down by 2.5 points ― that is, as big or bigger than we see with any of the Alzheimer's disease drug trials," principal investigator Alan J. Lerner, MD, director, Brain Healthy and Memory Center, and a staff neurologist at University Hospitals Case Medical Center, told Medscape Medical News.
The study was presented here at the Alzheimer's Association International Conference (AAIC) 2014.
Reluctance to Operate
Although Alzheimer's disease, other dementia types, and cataracts are frequently comorbid, healthcare providers are often reluctant to operate, the investigators note.
"The clinical issue is that patients may not be getting cataract surgery simply because they have dementia. Families often don't want to put them through it, and even doctors will often not recommend cataract removal ― whether it is a geriatrician, an internist, or even an ophthalmologist," said Dr. Lerner.
To evaluate the impact of cataract surgery on vision, cognition, and quality of life, the investigators recruited patients from dementia and ophthalmology clinics who were diagnosed with dementia and visually significant cataracts.
The trial included 2 cohorts ― an intervention group that underwent surgery immediately following trial enrollment (n = 28) and a control group that either refused surgery or delayed surgery for 6 months (n = 14).
In addition to visual acuity and cataract severity, cognitive status was measured using the MMSE and the Alzheimer's Disease Assessment Scale, Cognitive (ADAS-Cog).
The Neuropsychiatric Inventory (NPI) was used to assess patients' psychiatric symptoms, including anxiety, confusion, depression, and hallucinations, and caregiver stress was measured by NPI- Distress.
Participants were assessed at baseline before surgery and again at 6 months. The mean age of the study participants was 80 years for the intervention group and 83.6 years for the control group. In addition, Dr. Lerner noted that from a cognitive standpoint, the study population was "quite impaired," with mean MMSE scores of 18.75 and 16.93 for the intervention and control groups, respectively.
The analysis revealed that all patients in the intervention group had significantly improved vision. This may seem like an obvious result, said Dr. Lerner, but he pointed out that cataract surgery is not always a "slam dunk," so "it's good to know that vision does get better" in this patient population.
Secondly, noted Dr. Lerner, those who underwent immediate surgery experienced an improvement of 0.39 points in MMSE scores compared with a 2.31-point decline in the control group.
Results also showed a decrease in NPI scores of -4.71 in the intervention group compared with 3.92 in control individuals. Finally, NPI-Distress scores revealed a reduction in caregiver stress of -2.00 in the intervention group vs 0.93 in the control group.
"One of the most striking things to me was the reduction in neuropsychiatric symptoms in patients and the reduced caregiver burden and stress," said Dr. Lerner.
Although the mechanism between improved vision and the reduced rate of cognitive decline is not entirely clear, he speculated that it is likely an indirect effect.
He noted that sensory deprivation is associated with hallucinations, anxiety, and other psychiatric symptoms. Poor vision and subsequent cognitive decline may be the result of an inability to interact with the environment, he said.
Although preliminary, Dr. Lerner said the study's findings send a strong message, not just with respect to dementia patients with cataracts but potentially for dementia patients with other comorbid conditions.
"I think there's tremendous ambivalence about dementia and how aggressive we should be about comorbid illness. The implication from this study is that if it is going to improve things, then yes, we should be more aggressive, because it will have bottom-line effects ― improved behavior, quality of life, possible slower decline in cognition, and reduced caregiver stress. Lastly, it's important to remember that help does not always come in the form of a pill," he said.
Commenting on the findings for Medscape Medical News, Maria Carrillo, PhD, vice president, medical and scientific relations for the Alzheimer's Association, said the study highlights the importance of optimal healthcare for individuals with dementia.
Although it may be true that there is reluctance on the part of family members and/or clinicians to intervene with surgery or other invasive treatments, a potentially larger issue is the lack of screening for conditions such as vision and hearing loss.
"If a person with dementia falls because they can't see properly and has to be hospitalized because of a broken hip bone, they may never recover. In addition, vision loss is very socially isolating. I don't think people really understand that healthcare in general is a very important part of quality of life for people with dementia. This not only helps the patient, it also helps the family," she said.
Dr. Lerner and Dr. Carrillo report no relevant financial relationships.
Alzheimer's Association International Conference (AAIC) 2014. Abstract P1-388. Presented July 13, 2013.
Medscape Medical News © 2014 WebMD, LLC
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Cite this: Cataract Surgery May Cut Cognitive Decline in Dementia - Medscape - Jul 14, 2014.