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Objectives To evaluate the relevance of autoantibodies to carbonic anhydrase 6 (CA6), parotid secretory protein (PSP) and salivary gland protein 1 (SP1) on dry eye disease (DED) symptoms and signs.Methods and analysis A retrospective study of 115 individuals diagnosed with DED and tested for CA6, PSP and SP1 antibodies at the Miami Veterans Eye Clinic. Antibody status (positive: ≥1 antibody ≥20 EU/mL vs negative: all antibodies <20 EU/mL) and levels were analysed against DED metrics at baseline and follow-up (67 individuals).Results Of 115 individuals, 73 were antibody positive, with CA6 IgG most frequently elevated. Antibody-positive individuals had more severe DED symptoms (Ocular Surface Disease Index 56.64±22.56 vs 43.89±20.36, p=0.002) and greater tear film instability (5.38±3.52 vs 6.83±4.01 s, p=0.046). These associations remained significant in forward regression analyses. Quantitative antibody levels also related to ocular signs at baseline: corneal staining to SP1 IgA (r=0.36, p<0.001) and PSP IgM (r=0.19, p=0.04) and Schirmer scores to CA6 IgG (r=−0.19, p=0.04). At follow-up, 43% (n=29) showed an increase in DED symptoms and 82% (n=55) in at least one sign, with PSP IgM being most predictive for worsening DED status.Conclusions Our study suggests that CA6, PSP and SP1 antibody status and levels are relevant in DED. Antibody positivity correlated with more severe baseline symptoms and signs and individual antibody values predicted progression. Rather than markers of a systemic diagnosis, these autoantibodies may better reflect ocular disease severity and progression.