## 3 Results
### Clinical Features of the AD Subpopulation Differ from Those of the Non-AD Population  
A diagnosis of AD was confirmed in 44.3% (284/641) of the screened population. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **General Population** & **AD Population** & **Non-AD Population** & \(p\)**-Value \({}^{\star}\)** \\ \hline Patients N tot & 641 & 284 & 357 & \\ \hline Males n (\%) & 246 (38.4) & 96 (33.8) & 150 (42.0) & 0.033 \\ \hline Age (mean \(\pm\) SD) & 46.2 \(\pm\) 19.4 & 36.9 \(\pm\) 16.4 & 53.7 \(\pm\) 17.9 & \textless{}0.0001 \\ \hline BMI (mean \(\pm\) SD) & 24.3 \(\pm\) 4.4 & 23.5 \(\pm\) 4.4 & 25.1 \(\pm\) 0.23 & \textless{}0.0001 \\ \hline Previous diagnosis of AD n (\%) & 362 (56.5) & 219 (77.1) & 126 (35.3) & \textless{}0.0001 \\ \hline Disease duration (mean \(\pm\) SD) & 10.7 \(\pm\) 11.8 & 15.3 \(\pm\) 12.6 & 7.0 \(\pm\) 9.7 & \textless{}0.0001 \\ \hline Family history of AD n (\%) & 115 (17.9) & 66 (23.2) & 47 (13.1) & \textless{}0.0001 \\ \hline Family history of other atopic comorbidities n (\%) & 183 (28.5) & 109 (38.4) & 72 (20.2) & \textless{}0.0001 \\ \hline \multicolumn{5}{c}{**Job Title**} \\ \hline Intellectual jobs (white collars) n (\%) & 260 (40.6) & 124 (43.7) & 136 (38.1) & 0.176 \\ \hline Manual jobs (blue collars) n (\%) & 154 (24.0) & 78 (27.5) & 76 (21.3) & 0.069 \\ \hline \multicolumn{5}{c}{**Physicians Previously Consulted**} \\ \hline Dermatologist n (\%) & 542 (84.5) & 264 (93.0) & 278 (77.9) & \textless{}0.0001 \\ \hline Allergologist n (\%) & 219 (34.2) & 139 (48.9) & 80 (22.4) & \textless{}0.0001 \\ \hline General practitioner n (\%) & 39 (6.1) & 6 (2.1) & 33 (9.2) & \textless{}0.0001 \\ \hline \multicolumn{5}{c}{**Patient’s Related Outcomes**} \\ \hline Itch intensity (mean, SD) & 6.5 \(\pm\) 2.5 & 6.9 \(\pm\) 2.4 & 6.2 \(\pm\) 2.6 & 0.0003 \\ \hline Interference with sleep (mean \(\pm\) SD) & 4.4 \(\pm\) 3.4 & 5.0 \(\pm\) 3.4 & 3.9 \(\pm\) 3.4 & \textless{}0.0001 \\ \hline Interference with work (mean \(\pm\) SD) & 3.7 \(\pm\) 3.4 & 4.3 \(\pm\) 3.5 & 3.4 \(\pm\) 3.4 & 0.002 \\ \hline Interference with sport (mean \(\pm\) SD) & 3.4 \(\pm\) 3.4 & 4.1 \(\pm\) 3.4 & 2.8 \(\pm\On the other hand, 55.7% of subjects were included in the non-AD group, as they reported being affected by other purritic cutaneous disease, including seborrheic dermatitis, psoriasis, allergic contact dermatitis, scabies, prurigo nodularis, dermatitis herpetiformis, bullous pemphigoid, and pruritrus. Demographic and clinical data of each subpopulation are summarized in Table 1.  
Approximately 77% (219/284) of AD patients had previously received a diagnosis of AD. In 35.3% (126/357) of non-AD patients, an erroneous diagnosis of AD had been previously made. Most AD patients (93.0%; 264/284) visited a dermatologist at least once, compared to 77.9% (278/357) of the non-AD population, whereas 48.9% (139/284) of AD compared to 20.4% (80/357) of non-AD patients had visited their skin disease evaluated by an allergologist and 2.1% (6/284) of AD versus 9.2% (33/357) of non-AD patients by a general practitioner. Mean duration of skin disease was 15.3 \(\pm\) 12.6 years in the AD group and 7.0 \(\pm\) 9.7 in the non-AD group (\(p\)! 0.0001). A family history of AD, rhinoc conjunctivitis, and asthma was significantly more frequent in AD patients compared to non-AD patients (\(p\)! 0.0001). A higher intensity of pruritus and sleep deterioration were detected in the AD group, with mean values of itch- and sleep-NRS of 6.9 \(\pm\) 2.4 and 5.0 \(\pm\) 3.4, respectively, compared to 6.2 \(\pm\) 2.6 and 3.9 \(\pm\) 3.4 in the non-AD cohort (Table 1). Moreover, a higher grade of disease-related embarrassment and disease interference with sport and work was reported in the AD group compared with the non-AD population (Table 1). The regular use of TCS or TCI was reported in 44.3% (126/284) of AD patients compared to 37.2% (133/357) of non-AD patients (\(p\)! 0.0001). In addition, AD patients reported a greater use of moisturizers compared to non-AD patients (56.3% (160/284) versus 37.5% (134/357), \(p\)! 0.0001).