title: Estimation of depression prevalence in patients with Stargardt disease using PHQ-9 and Zung scores.
abstract: OBJECTIVE
  To evaluate the psychological impact and depression prevalence in patients with Stargardt disease.
  
  
  METHODS
  We conducted a case-control study including 39 patients with Stargardt disease and 32 age- and sex-matched healthy controls. All participants underwent a complete ophthalmologic examination and completed the Patient Health Questionnaire-9 (PHQ-9) and the Zung Depression Inventory questionnaire. Results were analyzed using IBM SPSS 22.0 software.
  
  
  RESULTS
  The patient group consisted of 19 men and 20 women with mean age of 36.9 ± 5.4 years and control group of 19 men and 13 women with mean age of 42.5 ± 10.1 years. The mean values of PHQ-9 and Zung scores for patients and healthy individuals were 10.9 ± 4.9, 46.7 ± 11.1, 6.7 ± 5.4, and 41.1 ± 8.5, respectively. There were statistically significant differences between the 2 groups in PHQ-9 scores (independent samples t test: p = 0.001), but not in Zung scores (Mann-Whitney test: p = 0.053). The PHQ-9 and Zung scores appeared to be moderately but significantly correlated (Pearson coefficient 0.44, p&lt;0.0001). In addition, PHQ-9 score seems to be raised along with age, whereas both scores are low when best-corrected visual acuity is high.
  
  
  CONCLUSIONS
  Patients with Stargardt disease exhibited more depressive symptoms compared to healthy individuals according mainly to PHQ-9 scores. Moderate depression was significantly correlated visual function decline.
authors.affiliation: 1 Department of Ophthalmology, Medical School, National & Kapodistrian University of Athens, Athens - Greece.
authors.forename: Marilita M
authors.initials: MM
authors.lastname: Moschos
authors.affiliation: 1 Department of Ophthalmology, Medical School, National & Kapodistrian University of Athens, Athens - Greece.
authors.forename: Eirini
authors.initials: E
authors.lastname: Nitoda
authors.affiliation: 1 Department of Ophthalmology, Medical School, National & Kapodistrian University of Athens, Athens - Greece.
authors.forename: Anastasios
authors.initials: A
authors.lastname: Lavaris
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003866:Depressive Disorder / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D006115:Greece / Q000453:epidemiology; D006801:Humans; D008268:Macular Degeneration / Q000151:congenital* / Q000453:epidemiology / Q000523:psychology; D008297:Male; D008875:Middle Aged; D010555:Personality Inventory; D015995:Prevalence; D012044:Regression Analysis; D000080362:Stargardt Disease; D011795:Surveys and Questionnaires; D014786:Vision Disorders / Q000453:epidemiology* / Q000523:psychology; D014792:Visual Acuity; D019987:Persons with Visual Disabilities / Q000523:psychology / Q000706:statistics & numerical data*