Parkinson’s Patients Have More Vision Problems, Require Better Screening, Study Says

emotions and expressions

Parkinson’s disease patients have a higher rate of vision problems compared with the general population, and require screening for ophthalmologic symptoms to enable more timely treatment, according to a recent study.

The study, “Seeing ophthalmologic problems in Parkinson disease,” was published in Neurology.

Parkinson’s is defined by the death of dopamine-producing (dopaminergic) neurons. Loss of dopamine in the retina — a thin layer of tissue in the back of the eyes that is critical for converting light into nerve impulses — causes various visual problems, including difficulty in controlling eye movements, contrast sensitivity, or color vision.

Evidence suggests that many ophthalmologic symptoms go underreported among Parkinson’s patients. An estimated 80% of visual impairments are treatable or preventable, given timely action.

To get a more accurate estimate of vision problems among those with Parkinson’s, researchers from the Radboud University Medical Center in Nijmegen, the Netherlands, conducted a multi-center study of 1,098 people, including 848 Parkinson’s patients who had symptoms for an average of seven years, and 250 age-matched controls. They all completed the newly developed Visual Impairment in Parkinson’s Disease Questionnaire (VIPD-Q). The average age of both groups was 70.

In the questionnaire, participants rated how often they experienced symptoms in sentences such as “I have a burning sensation or gritty feeling in my eyes,” “I can read better with one eye closed,” “Colors seem to be paler than before,” and “I see things that other people do not see (hallucinations).”

Results showed that 82% of participants with Parkinson’s experienced ophthalmologic symptoms, compared with 48% of the controls.

Certain symptoms appeared almost exclusively among those with Parkinson’s. These included seeing colors less brightly, double vision, difficulty with depth perception, and visual hallucinations. Symptoms such as watery eyes, light sensitivity, and glare at night were also common among controls.

Furthermore, 68% of those with Parkinson’s reported daily problems related to vision impairments, compared with 35% of the controls.

“The effect of ophthalmologic symptoms may be particularly vexing for patients with [Parkinson’s] because of their need to compensate for their motor deficits by guiding their movements visually,” the researchers wrote.

This is reflected in the 22% of participants with Parkinson’s who reported vision-related difficulties with walking and performing hobbies. A further 33% reported that their vision problems interfered with driving.

Those with higher VIPD-Q scores also reported more frequent falls. This result is in line with other reported associations between the severity of vision problems and the severity of gait impairment in Parkinson’s.

Because the study relied on voluntary self-reporting, there is room for some bias in the data. First, it is possible that patients with visual problems were more likely to participate. Second, relying only on self-reported symptoms is a very subjective measure.

Despite these limitations, the results of the study highlight the need for more research on associations between Parkinson’s and visual deficits, and a need for better screening.

“People with Parkinson’s who express that they have eye problems should be referred to a specialist for further evaluation,” study author Carlijn Borm, MD, said in a press release. “For those who do not express such problems, using a questionnaire to screen for problems that may otherwise be missed might allow for recognition, timely treatment and improving the quality of life.”

The post Parkinson’s Patients Have More Vision Problems, Require Better Screening, Study Says appeared first on Parkinson’s News Today.

Italian Self-rating Scale for Quality of Life in Parkinson’s Patients Validated in Study

quality of life scale

The Italian version of the scale most often used to determine quality of life in patients with Parkinson’s disease (PD) — the self-report 39-Item Parkinson’s Disease Questionnaire (PDQ-39) — has been validated for Italian patients, a study reports.

The Italian form of the survey (PDQ-39-IT) can now reliably be used in clinical practice and research to measure the effect of treatments in the quality of life of Italian Parkinson’s patients.

The study, “Quality of life in Parkinson’s disease: Italian validation of the Parkinson’s Disease Questionnaire (PDQ-39-IT),” was published in the journal Neurological Sciences.

The PDQ-39 has been the most widely used measure of health status and quality of life in Parkinson’s patients. It is helpful not only for clinical practice but also for research as an outcome measure in clinical trials testing potential treatments.

It is a scale designed specifically for Parkinson’s patients, containing 39 questions that ask how often patients have difficulties in eight domains: mobility, activities of daily living, emotional well-being, stigma, social support, cognition, communication, and bodily discomfort.

Since its development in 1995, the questionnaire has been translated, culturally adapted, and validated into 13 different languages.

Before a test can be employed for research or examination purposes, its validity needs to be ensured, and although an Italian translation and adaptation of this test was launched in 2008 — the PDQ-39-IT — its validity had never been verified. 

Researchers have now tested the PDQ-39-IT in 104 patients diagnosed with Parkinson’s disease (mean age 65.7, mean duration of symptoms 7.4 years). Participants were recruited from June to October 2017 from two university hospitals in Rome: the Sapienza University and Tor Vergata University.

An important measure of a scale’s reliability is its internal consistency — that is, how closely related the items within a test are as a group.

To address this, researchers used a statistical coefficient called the Cronbach’s alpha. Except for social support, all other dimensions surveyed by PDQ-39-IT displayed a high Cronbach’s alpha of 0.70 or above. They were also within the range of those found in the original version of the test.

Researchers also examined another measure of a test’s coherence, called test-retest reliability. A subgroup of 35 patients was asked to complete the survey twice, with an interval of three days between the surveys. The scores obtained in the two surveys were compared. There was a high level of agreement between the test and the retest scores for all dimensions tested.

As a measure of the test’s validity, researchers compared the scores obtained in PDQ-39-IT for each patient with those obtained with the Italian version of  36-Item Short Form Health Survey (SF36) — another well-established patient-reported measure of health status.

All dimensions of PDQ-39-IT showed a positive and significant association with the SF-36 questionnaire, again demonstrating the test’s validity.

Overall, the study indicates that PDQ-39-IT “is an acceptable, valid, and reliable tool to measure the quality of life of Italian [Parkinson’s] patients,” researchers wrote.

“It provides Italian clinicians with a valid, reliable, rapidly administrable, and standardized scale to measure quality of life in [Parkinson’s disease], thereby enabling clinicians in all healthcare and rehabilitation professions to make informed decisions,” they added.

In addition, the test is a valuable tool to address the outcome of interventions over the quality of life of Italian Parkinson’s patients participating in clinical trials.

The post Italian Self-rating Scale for Quality of Life in Parkinson’s Patients Validated in Study appeared first on Parkinson’s News Today.

Source: Parkinson's News Today