Minimal clinically important difference for the rhinoconjunctivitis quality of life questionnaire in allergic rhinitis in Thai population

BACKGROUND: Clinical measurement of the severity of allergic rhinitis (AR) can be assessed by symptoms score and patient quality of life (QoL). The magnitude of change in both symptoms and patient QoL should be considered in the management of AR. OBJECTIVE: The aim of this study was to determine the minimal clinically important difference (MCID) in AR in Thai population. METHODS: This prospective study recruited AR patients that attended our clinic during September 2011 to February 2012. The Rhinoconjunctivitis Quality of Life (Rcq-36) questionnaire was used to evaluate patient QoL. The Global Rating of Change Scale (GRCS) was used to assess improvement or deterioration in condition. The MCID was determined using an anchor-based method based on the GRCS, which was compared to the MCID determined by a distribution-based method based on the standard deviation (SD). RESULTS: Three hundred seventy-two patients with chronic rhinitis were recruited. Eighty-four of those had positive skin prick test and be diagnosed as AR. Of those, 79 completed the study and were included in the final analysis. A change of 2 points on the GRCS yielded an MCID for overall QoL of 0.21 ± 0.57. When applying the distribution-based method, an SD of 1.5 SD yielded an MCID for QoL of 0.27. For the rhinitis symptoms domain, the MCID was 0.42 ± 0.72. CONCLUSIONS: The MCID for overall QoL and rhinitis symptoms in Thai AR patients was found to be 0.21 ± 0.57 and 0.42 ± 0.72, respectively. MCID can be applied for determining the clinical significance of treatment efficacy in AR.

A Survey of Allergic Diseases in University Students of Bangkok, Thailand

A survey of allergic diseases was performed on 1,147 students of Mahidol University using a standardised questionnaire. They were all students in the medical and paramedical schools, and ages ranged form 16 to 34 years. Prevalence of allergic diseases, listed in decreasing frequency was as follows : urticaria 37.3%, allergic rhinitis 21.9%, food allergy 16.6%, drug allergy 11%, stinging insect allergy 7.5% and asthma 4.8%. When compare to the study done in the students of the same university twenty years ago, there was no difference in the prevalence of allergic rhinitis, however asthma prevalence increased by two folds. Urticaria and stinging insect allergy decreased and there was slight increase in food and drug allergies. Study in subjects with allergic rhinitis showed that age at onset before 19 years old and moving to big city significantly increased the risk for developing allergic rhinitis, while other factors i.e. sex, associated allergy, family history of atopy, birth season and pets were not the risk factors.

A Study of Nasal Airway Resistance and Nasal Airflow in Augmentation Rhinoplasty

Active anterior rhinomanometry (AAR) was performed in 42 patients with low-profile or saddle noses before augmentation rhinoplasty (AR) and after AR. The purpose was to measure nasal airway resistance (NAR) and nasal airflow (NAF). There were 38 females and 4 males, whose ages ranged from 15 to 42 years (mean 29.6 years). Preoperative total NAR at 75 Pascals (Pa) was 0.24+/-0.09 and 0.20+/-0.06 Pa/ml/sec for the non-decongested and decongested value respectively. Two weeks postoperatively, the total NAR was 0.19+/-0.06 and 0.15+/-0.05 Pa/ml/sec for the non-decongested and decongested value respectively, which was significantly less than the preoperative value. The postoperative total NAF was 422.31+/-137.05 cm3 and 514. 57+/-152.45 cm3 for the non-decongested and decongested value respectively, which was significantly increased when compared to the preoperative value (342.57+/-109.27 cm3 and 399.90+/-106.98 cm3 for the non-decongested and decongested value respectively). The comparison between the changes in NAR and subjective nasal breathing showed that the postoperative NAR decreased in 88.10% of patients while subjective nasal breathing improved in only 52.38%. Postoperative NAR increased in 9.52% of patients, while subjective nasal breathing was worsened in 2.38%. The results of this study indicate that AR has decreased the NAR and increased NAF, and thus improving the nasal breathing. From this preliminary study it is concluded that AR is useful not only for the aesthetic aspect but also for its effect on the function of the nose, especially on the improvement of nasal breathing.