Development and external validation of the DOAT and DOATS scores: simple decision support tools to identify disease progression among nonelderly patients with mild/moderate COVID-19
Authors: Shibata Yoko , Minemura Hiroyuki , Suzuki Yasuhito , Nikaido Takefumi , Tanino Yoshinori , Fukuhara Atsuro , Kanno Ryuzo , Saito Hiroyuki , Suzuki Shuzo , Ishii Taeko , Inokoshi Yayoi , Sando Eiichiro , Sakuma Hirofumi , Kobayashi Tatsuho , Kume Hiroaki , Kamimoto Masahiro , Aoki Hideko , Takama Akira , Kamiyama Takamichi , Nakayama Masaru , Saito Kiyoshi , Tanigawa Koichi , Sato Masahiko , Kanbe Toshiyuki , Kanzaki Norio , Azuma Teruhisa , Sakamoto Keiji , Nakamura Yuichi , Otani Hiroshi , Waragai Mitsuru , Maeda Shinsaku , Ishida Tokiya , Sugino Keishi , Inage Minoru , Hirama Noriyuki , Furuyama Kodai , Fukushima Shigeyuki , Saito Hiroshi , Machiya Jun-ichi , Machida Hiroyoshi , Abe Koya , Iwabuchi Katsuyoshi , Katagiri Yuji , Aida Yasuko , Abe Yuki , Ota Takahito , Ishizawa Yuki , Tsukada Yasuhiko , Yamada Ryuki , Sato Riko , Omuna Takumi , Tomita Hikaru , Saito Mikako , Watanabe Natsumi , Rikimaru Mami , Kawamata Takaya , Umeda Takashi , Morimoto Julia , Togawa Ryuichi , Sato Yuki , Saito Junpei , Kanazawa Kenya , Omae Kenji , Noriaki Kurita , Iseki Ken 
Published: December 2021

BACKGROUND

Due to the dissemination of vaccination against severe acute respiratory syndrome coronavirus 2 in the elderly, the virus-susceptible subjects have shifted to unvaccinated non-elderlies. The risk factors of COVID-19 deterioration in non-elderly patients without respiratory failure have not yet been determined. This study was aimed to create simple predicting method to identify such patients who have high risk for exacerbation.

METHODS

We analyzed the data of 1,675 patients aged under 65 years who were admitted to hospitals with mild-to-moderate COVID-19. For validation, 324 similar patients were enrolled. Disease progression was defined as administration of medication, oxygen inhalation and mechanical ventilator starting one day or longer after admission.

RESULTS

The patients who exacerbated tended to be older, male, had histories of smoking, and had high body temperatures, lower oxygen saturation, and comorbidities such as diabetes/obesity and hypertension. Stepwise logistic regression analyses revealed that comorbidities of diabetes/obesity, age ≥ 40 years, body temperature ≥ 38°C, and oxygen saturation < 96% (DOATS) were independent risk factors of worsening COVID-19. As a result two predictive scores were created: DOATS score, which includes all the above risk factors; and DOAT score, which includes all factors except for oxygen saturation. In the original cohort, the areas under the receiver operating characteristic curve of the DOATS and DOAT scores were 0.789 and 0.771, respectively. In the validation, the areas were 0.702 and 0.722, respectively.

CONCLUSION

We established two simple prediction scores that can quickly evaluate the risk of progression of COVID-19 in non-elderly, mild/moderate patients.

The risk stratification models using independent risks, namely comorbidity of diabetes or obesity, age ≥ 40 years, high body temperature ≥ 38□, and oxygen saturation < 96%, DOATS and DOAT scores, predicted worsening COVID-19 in patients with mild-to-moderate cases.