## 4 Discussion  
The SNOT-22 is a patient-reported outcome measure (PROM) commonly used to assess the impact of CRS on HRQoL and can be a useful tool to evaluate the benefits of a treatment on patients' health [16,17]. In our study, the median SNOT-22 score in N-ERD patients on nasal LAS was 20 points lower than in those off LAS and this was statistically significant (\(p=0.02\)). So far, several studies have confirmed an improvement in the reported sinonasal symptoms in patients undergoing oral ATAD, as well as in the long term. [PERSON] et al. [18] found a statistically significant improvement in the SNOT-20 score in a placebo-controlled randomized trial of ASA desensitisation in ASA-tolerant and ASA-intolerant asthmatics. [PERSON] et al. [19] found a statistically significant improvement in SNOT-22 in the desensitisation arm at 6 months when comparing 16 ASA desensitisation patients to 16 controls. [PERSON] et al. [20] observed a significant improvement in the SNOT-22 score in 19 patients randomized to ASA when compared to 19 receiving a placebo. \begin{table}
\begin{tabular}{l r r r r} \hline  & \multicolumn{1}{c}{**Whole**} & \multicolumn{1}{c}{**On LAS**} & \multicolumn{1}{c}{**Not on LAS**} & \\  & \multicolumn{1}{c}{**n = 34**} & \multicolumn{1}{c}{**n = 21**} & \multicolumn{1}{c}{**n = 13**} & \multicolumn{1}{c}{**\(p\)-Value**} \\ \hline sVAS, median [P25-P75] & 0.0 [0.0–3.0] & 0.5 [0.0–3.0] & 0.0 [0.0–2.5] & \\ Missing & 3 & 1 & 2 & 0.67 \\ SNOT-22 score, median [P25-P75] & & & & \\ Rhinologic symptoms & 19.0 [11.0–21.0] & 14.5 [8.5–21.0] & 21.0 [16.0–27.0] & **0.05** \\ Ear/Facial symptoms & 3.0 [1.0–7.0] & 3.0 [0.5–7.0] & 5.0 [2.0–9.0] & 0.22 \\ Sleep dysfunction & 5.5 [2.3–10.0] & 5.0 [2.0–7.0] & 8.0 [4.0–12.0] & 0.07 \\ Function status & 4.5 [1.0–8.8] & 3.0 [1.0–8.0] & 8.0 [6.0–9.0] & **0.02** \\ Emotion status & 3.0 [0.3–6.0] & 2.0 [0.0–4.0] & 6.0 [3.0–9.0] & **0.01** \\ Decreased sense of smell/taste \({}^{+}\) & 5.0 [3.0–5.0] & 4.0 [3.0–5.0] & 5.0 [4.0–5.0] & 0.41 \\ Total SNOT-22 score & 36.0 [24.0–51.0] & 29.0 [19.5–43.5] & 49.0 [29.0–62.0] & **0.02** \\ Missing & 1 & 1 & 0 & \\ \hline \end{tabular} sVAS: visual analogue scale for sense of smell; SNOT-22: 22-item Sino-Nasal Outcome Test.  
\end{table} 
Table 2: Patient-reported outcome measures (PROMs) in the whole population and according to intranasal lysine aspirin (LAS) use. Level of significance \(p\leq 0.05\). Significant \(p\) values in bold. \({}^{+}\) This item is already included in the “rhinologic symptoms” and, thus, has not been considered when calculating the total SNOT-22 score. Figure 2: Box plots showing SNOT-22 domain scores in patients on or off intranasal lysine aspirin. SNOT-22: 22-item Sino-Nasal Outcome Test. [PERSON] et al. [21] reported improved QoL scores on the Rhinosinusitis Disability Index in 18 ASA-desensitised patients compared to 13 controls at 36 months after sinus surgery. Similar results were found by [PERSON] et al. [22] using modified validated QoL questionnaires. In a previous study, [PERSON] et al. [23] observed a significant decrease in the SNOT-22 median score of an average of 10 points after 6 months of maintenance therapy. However, to the best of our knowledge, this is the first study evaluating the HRQoL in patients on intranasal ATAD using LAS. Interestingly, the 20-unit difference found in the total score of the SNOT-22 in our N-ERD patients on and off nasal LAS was higher than that observed in patients on oral ATAD in a recent meta-analysis (difference of 10.27 units) [11]. The lower SNOT-22 scores found in our patients on intranasal LAS could also be related to better tolerability of nasal ATAD compared to the oral one. In fact, it is well-known that people on oral ATAD can develop symptoms affecting the skin, gut, or lungs, and in previous studies conducted by our team, we confirmed a lower rate of side effects in patients using intranasal LAS when compared to those on oral aspirin, including lower risk of gastrointestinal bleeding or urticial rash [14; 15].