Evaluating the Misdiagnosis of Add in Patients With Prior History of Depression: A Claims Data Study in Germany

OBJECTIVES: Attention Deficit Disorder (ADD) is oftentimes misdiagnosed as depression, and literature highlights this is especially seen in women. Thus, the objective of this study was to estimate the incidence rate of ADD in women and men previously diagnosed with depression, as well as to determine factors associated with the potential misdiagnosis.

METHODS: This study utilized data from a German sickness fund (AOK PLUS), covering 1/1/2015-30/6/2021. Patients of all ages were included if they had ≥1 confirmed or suspected diagnosis of depression (ICD-10 F32/F33) from a specialist between 1/1/2016-30/06/2021 and no confirmed or suspected diagnosis of ADD prior to the depression diagnosis. Incident ADD diagnosis was defined as either a confirmed or suspected diagnosis during follow-up period. To assess the risk factors associated with potential misdiagnosis, a multivariate cox regression analysis was conducted accounting for age, sex and mental health comorbidities.

RESULTS: Of 196,480 patients with depression (mean age: 58.5 years, females: 68.78%), 858 patients (0.44%, mean age: 36.9 years) were later diagnosed with ADD, 78.32% received a confirmed ADD diagnosis. The incident rate was 0.65% in males and 0.35% in females.

From mental health comorbidities known to be associated with ADD, the top five observed within those with ADD were anxiety and depressive disorder (ICD-10 F41.2; 12.70%), anxiety disorder (ICD-10 F41.9; 10.2%), panic disorder (ICD-10 F41.0; 9.56%), generalized anxiety (ICD-10 F41.1; 7.58%), and dysthymic disorder (ICD-10 F34.1; 6.41%).

The Cox-regression analysis confirmed that males (Hazard Ratio (HR): 0.52, p<0.001), younger patients (HR: 0.94, p<0.001) and those with more mental health comorbidities (HR: 1.10, p=0.002) were more likely to receive an ADD diagnosis after being initially diagnosed with depression.

CONCLUSIONS: Despite literature, males are more likely to be diagnosed with ADD after initial depression diagnosis. Further research should be conducted to measure the sexual bias of existing ADD diagnostic tools.