A cross-sectional study by Dr Vijaya K Gothwal and colleagues from the Patient Reported Outcomes Unit, Brien Holden Eye Research Centre, L V Prasad Eye Institute and The University of New South Wales, Sydney, reports on the factors affecting the quality of life (QoL) of persons with Keratoconus. This large study measured keratoconus’ impact on two aspects, activity limitations and symptoms, using a Keratoconus-specific questionnaire and found that female participants and those employed reported lower QoL in terms of being troubled by symptoms.
Keratoconus is a chronic condition that causes a steepening distention of the cornea. The condition may vary from mild to severe in severity and can cause a variety of optical imperfections, leading to vision impairment and even corneal scarring. A patient with keratoconus will find their vision distorted. This increases their difficulty in performing daily tasks, which in turn adds stress and anxiety to their lives. These functional difficulties generally don’t get captured in the traditional assessments in the clinic and are best captured by gathering patient’s perspectives through patient-reported outcome measures. Keratoconus manifests around puberty and progresses for a decade or more—that is, during some of the most active years of a person’s life. So, along with clinical assessment, patient-reported outcome measures are important and critical to understanding keratoconus’ impact on a person’s QoL.
The Collaborative Longitudinal Evaluation of Keratoconus (CLEK) study across 16 clinics in USA is the largest QoL study on keratoconus. The CLEK group assessed 1,209 keratoconus patients on QoL using the National Eye Institute Visual Function Questionnaire (NEI VFQ) over eight years (1998-2006). It found that women were more likely to report ocular issues, and that as the severity of keratoconus increased, so did the reported decrement in QoL. Over time, other studies with a variety of questionnaires have been assessing QoL in persons with keratoconus. However, all these questionnaires were developed for eye disorders other than keratoconus (such as cataract) and so lacked keratoconus-specific content. This lack of specificity reduces the sensitivity of these tools to assess patient-reported outcomes in keratoconus.
A new, cross-sectional study led by Dr Vijaya K Gothwal and her colleagues from L V Prasad Eye Institute and the University of New South Wales, Australia, systematically measured clinical and socio-demographic factors that influence QoL in adults with Keratoconus. The study included 574 participants (57% male) with mild to severe keratoconus. Over 80% had a college degree or higher. Using a keratoconus-specific questionnaire, the Keratoconus Outcomes Research Questionnaire (KORQ), the study found that women and working individuals reported greater difficulty dealing with the symptoms of keratoconus. Unlike CLEK, the study did not find any relationship between the severity of the clinical assessment and reported QoL, where patients with mild keratoconus can also experience visual disturbances that are debilitating.
A key strength of this paper is its use of KORQ. The questionnaire is disease-specific and its two-part structure captures visual abilities and symptoms, where each part is unidimensional and psychometrically valid. This rigour and the specificity of KORQ gives great credence to the paper’s findings, especially where they diverge from previous studies like CLEK. The study also speculates on a variety of factors that may explain why significantly more women report worse QoL. This is now the largest study of adults with keratoconus to have used a disease-specific tool (KORQ) to measure QoL.
'Clinicians who treat patients with keratoconus should pay greater attention to the heightened symptoms reported by women and by those working,' says Dr Vijaya Gothwal, Head – Patient Outcomes Research Unit at LVPEI. 'It may help to include in their consultation, questions regarding the workplace environment of the patients. They should note the need to avoid dry and smoky areas as much as possible.'
'Clinicians should be cognizant of the fact that even a mild form of keratoconus can have significant impact on visual functioning and cause increased discomfort from symptoms in patients. This subset of patients needs as much attention as those with severe forms of the disease,' she concludes.
Citation
Gothwal VK, Gujar R, Sharma S, Begum N, Pesudovs K. Factors affecting quality of life in keratoconus. Ophthalmic Physiol Opt. 2022 May 30. doi: 10.1111/opo.13010. Epub ahead of print. PMID: 35638140.