**Background:** Computer vision syndrome (CVS), also known as digital eye strain, encompasses visual and ocular symptoms resulting from prolonged use of electronic devices (ED), including dry eyes, eyestrain, blurred vision, and headache. Presbyopic individuals (aged 45–65) are particularly vulnerable due to age-related changes in accommodation and the need for optical correction for near and intermediate vision. The COVID-19 pandemic accelerated the shift to teleworking, potentially worsening CVS symptoms. This study aimed to evaluate the prevalence of CVS-related symptoms in presbyopic computer workers and their association with ED use habits and ergonomic factors.
**Methods:** A web-based questionnaire was disseminated via the University of Murcia's social networks from February to March 2021. Inclusion criteria were presbyopic participants aged 45–65 years who used a computer as their main work tool. Of 259 responses, 198 were included after excluding 61 who did not work with a computer. The questionnaire covered demographics, optical correction, ED use habits, ergonomic conditions, and 10 CVS-related symptoms (blurred vision while viewing computer, blurred distance vision after computer work, difficulty/slowness in refocusing, irritated/burning eyes, dry eyes, eyestrain, headache, tired eyes, sensitivity to bright lights, eye discomfort). Each symptom was rated on a 0–4 scale (never=0, sometimes=1, half the time=2, most of the time=3, always=4), and the median total symptom score (MTSS) was calculated as the sum of scores (maximum 40). Scores ≥8 were considered indicative of CVS. Statistical analysis used Kruskal-Wallis tests and multivariate linear regression, with significance set at p<0.05.
**Key Results:** The sample included 125 females (63.1%) and 73 males (36.9%), with a median age of 54±8 years. The overall MTSS was 7±5 (IQR 5). The most common symptoms reported 'half of the time' or more were tired eyes (17.2%), dry eyes (16.7%), difficulty refocusing (12.6%), and blurred distance vision after computer work (11.1%). MTSS was significantly higher in females (8±5) than males (6±5, p<0.05), with significantly higher scores for dry eyes (p<0.01), headache (p<0.05), and tired eyes (p<0.01). No significant differences were found by age (p=0.36) or type of optical correction (p=0.64 for usual correction; p=0.34 for computer work correction), though bifocal and single near-vision lens users had higher MTSS (10±10 and 7.5±7, respectively) compared to progressive (6±4) or occupational lens users (5±4.75).
Regarding working conditions, MTSS was significantly higher in home teleworkers (8±5) than office workers (7±4.5, p<0.05), with difficulty refocusing significantly higher in teleworkers (p<0.05). Laptop users had significantly higher MTSS (9±6) than desktop users (6±4, p<0.05), with dry eyes (p<0.01) and tired eyes (p<0.05) being significantly higher. Daily hours of computer use for work (≥6 vs. <6 hours) showed a trend but no significant difference (p=0.21). Total daily ED use (0–5, 6–10, >10 hours) also showed no significant difference (p=0.21), but tired eyes was significantly higher in those using ED >10 hours/day (p<0.001). Participants who were always teleworking had significantly higher MTSS (8±5) than those who previously worked at the office (7±4, p<0.001), and those reporting worsening of symptoms had higher MTSS (9±6.5) than those without worsening (6±6).
Multivariate linear regression showed MTSS was significantly correlated with gender (standardized β=0.145; p<0.05) and total daily hours of ED use (standardized β=0.139; p<0.05), but not with place of work (standardized β=0.120; p=0.09).
ERGONOMIC FACTORS
Participants with adequate lighting had significantly lower MTSS (7±5) than those without (10±6, p<0.05). Those who took breaks every 30 minutes had significantly lower MTSS (6±4) than those who took no breaks (8±7, p<0.01), with headache significantly lower in the break group (p<0.01). Screen position relative to eye level showed no significant difference (p=0.42). Participants reporting neck pain had significantly higher MTSS (8±5.75) than those without (6±5, p<0.01), and those with back pain had significantly higher MTSS (9±6) than those without (6±3.5, p<0.001). Symptoms significantly higher in those with neck/back pain included dry eyes (p<0.01), tired eyes (p<0.01), headache (p<0.01), and sensitivity to bright lights (p<0.01).
**Clinical Implications:** This study identifies key modifiable risk factors for CVS in presbyopic computer workers, including female gender, laptop use, home teleworking, inadequate lighting, infrequent breaks, and neck/back pain. The findings underscore the importance of ergonomic interventions such as proper lighting, regular breaks (e.g., every 30 minutes), and optimizing workstation setup (e.g., screen at eye level). Eye care practitioners should educate patients, especially presbyopic teleworkers, on these preventive measures. The study's limitations include a relatively small sample size, potential selection bias (participants with symptoms may be more likely to respond), lack of clinical measurements (e.g., visual function, ocular pathology), and reliance on self-reported ergonomic conditions. Future research should incorporate objective assessments and larger samples to confirm these associations and explore optimal optical corrections for computer work.