Proportion and clinical characteristics of keratoconus among patients attending refraction units: a retrospective facility-based study in Malawi.

PURPOSE: This study assessed the facility-based proportion, demographic profile, clinical characteristics, and factors associated with KC among patients attending tertiary referral refraction clinics in Malawi.

METHODS

A retrospective cross-sectional review of clinical records was conducted at Malawi's four national referral eye hospitals. Records of patients aged 10-45 years who attended refraction services between January 2014 and December 2018 were reviewed. KC cases were ascertained using predefined clinical criteria. Analyses were performed using R version 4.5.1 (R Foundation for Statistical Computing).

RESULTS

Of the 1,400 targeted records, 1,180 (84.3%) were successfully retrieved. The facility-based proportion of KC was 5.7% (67/1180; 95% CI: 4.4-7.2%). KC was most common among individuals aged 18-35 years (p = 0.001) and varied significantly by facility and region (p < 0.005). Blurred vision was the predominant presenting complaint (88.1%), while diagnosis relied primarily on retinoscopy, slit-lamp examination, and keratometry. Significant inter-eye differences were observed for best-corrected visual acuity and astigmatic axis (p < 0.005), but not for keratometric measurements. Median visual acuity improved from 0.2 to 0.6 following refractive correction. In multivariable analyses, cylindrical refractive error remained independently associated (AUC ≈ 0.88) with KC, whereas age and gender were not. Sensitivity analyses produced findings consistent with the primary results.

CONCLUSION

Keratoconus represents a substantial clinical burden within Malawi's tertiary eye-care system and is associated with considerable visual impairment. Strengthening early detection, access to corneal imaging, specialised rehabilitation services, and clinical information systems may improve diagnosis, management, and visual outcomes.