Abstract:

PRECIS:In a cohort study of 120,307 participants with 25+ years of follow-up, a history of non-melanoma skin cancer was associated with a 40% higher exfoliation glaucoma risk. PURPOSE:To evaluate the relationship between non-melanoma skin cancer (a marker of ultraviolet radiation exposure) and exfoliation glaucoma (XFG). METHODS:We performed a cohort study of US women (n=79,102; 1980-2014) and men (n=41,205; 1986-2014), aged 40+ years and at risk for glaucoma who reported eye exams. From 1984 (women)/1988 (men), we asked about basal cell carcinoma (BCC) or squamous cell carcinoma (SCC) history separately; in prior years, we asked about any non-melanoma skin cancer history in a single question. SCC was confirmed with histopathology reports while BCC and any early (<1984/<1988) non-melanoma skin cancer history was self-reported. Incident XFG cases (362 women and 83 men) were confirmed with medical records. Using pooled data, we estimated multivariable-adjusted relative risks (MVRR; 95% confidence intervals [CIs]) with Cox proportional hazards models that were stratified by age (in months), 2-year time period at risk and average lifetime residential latitude. RESULTS:In multivariable-adjusted analyses, we observed a 40% higher XFG risk with any non-melanoma skin cancer history (MVRR=1.40; 95% CI=1.08,1.82); the association was observed even with 4 and 8 year lags in non-melanoma skin cancer history. Also, the non-melanoma skin cancer association was stronger in younger (<65▒y; MVRR=2.56; 95% CI=1.62,4.05) versus older participants (≥65▒y; MVRR=1.25; 95% CI=0.94,1.66; p for interaction=0.01) and those living in northern latitudes (≥42° north; MVRR=1.92; 95% CI=1.28,2.88) versus more southern latitudes (<42° north; MVRR=1.19; 95% CI=0.86,1.66; p for interaction=0.04). CONCLUSIONS:Non-melanoma skin cancer was associated with higher XFG risk, particularly among younger participants and those living in Northern US.