Validation of Oral Health Impact Profile-14 and its association with Hypossialia in a Sjögren Syndrome Portuguese Population.

Aims: The objective of this study was to perform the Portuguese transcultural adaptation of the original Brazilian version of the Oral Health Impact Profile-14 (OHIP-14) while evaluating the association between hyposalivation and quality of life in a Sjögren´s Syndrome population.

Methods: The original Brazilian version of the Oral Health Impact Profile-14 was culturally adapted following the guidelines for cross-cultural adaptation of health-related quality of life measures. The questionnaires were administered by trained and calibrated dental doctors to 86 patients with Sjögren´s Syndrome. Oral Health Impact Profile-14 properties were examined including reliability, internal consistency and test-retest reliability, using Cronbach's alpha, total and inter-item correlation, and intra-class correlation coefficients, respectively. Whole saliva secretion rates and hyposalivation-related variables were collected and statistically analyzed. Spearman´s rho correlations were obtained between salivary flows and OHIP -14 domains and total score. Alpha was set at 0.05. Informed consents and local ethical committee clearance were obtained.

Results: Each question of the questionnaire performed adequately. Cronbach alpha values for the 14 questions were 0.89 for both test administrations and were lower if item removed. Scores for both questionnaire administration and ICC results presented good to excellent reliability with ICC ranging from 84% to 92%. Mean salivary flow rate was 0.05 (SD: 0.03) ml/min and mean stimulated salivary flow was 0.57 (SD: 0.44) ml/min, which are within expected values in a population with hyposalivation. The results describe a negative and significant correlation between total OHIP-14-PT score, physical pain, physical disability domain and stimulated and differential salivary flows. There was a negative and significant correlation between unstimulated salivary flow with physical pain.

Conclusion: Within the limitations of this study, the OHIP-14-PT seems to be a valid and reliable instrument for measuring oral health related quality of life in patients with Sjögren´s Syndrome. Both differential and stimulated salivary flows seem to correlate negatively with age and the quality of life is significantly diminished by lower stimulated salivary flow rates.