OBJECTIVES: “Post-COVID” conditions include a wide range of new health problems following COVID-19 infection. The ICD-10-GM code for post-COVID (U09.9!) became effective on 01/01/2021, but may not identify all post-COVID symptoms. We used claims data from AOK PLUS, a large regional sickness fund covering ≈3.7 million inhabitants in Saxony and Thuringia, to describe incident diagnoses following COVID-19 hospitalization.

METHODS: Inpatient cases of confirmed COVID-19 (ICD-10-GM code U07.1) between 01/01/2020—30/06/2021 with minimum 60 days follow-up were included. Long-COVID conditions were identified as incident ICD-10-GM inpatient or outpatient diagnoses occurring in the 31-180 days after COVID-19 discharge date that did not occur in the 1-year baseline period before COVID-19 hospitalization, excluding diagnoses due to pregnancy and external causes of morbidity.

RESULTS:

There were 18,251 inpatient COVID-19 patients, of which 12,162 (66.6%) had incident post-COVID conditions (65.2% outpatient only, 7.8% inpatient only, 27.0% inpatient and outpatient). Of patients diagnosed with COVID-19 in 2021, only 2245 (21.5%) were diagnosed with post-COVID condition (U09.9!).

Respiratory symptoms were most common (J00-J99, 20.7%), with 6.7% experiencing respiratory failure (J96). Heart disease (I20-I52) and urinary complications (N30-N39, R30-R39) were also frequent (18.3% and 18.1%, respectively), most commonly heart failure (I50, 5.7%) and urinary incontinence (R32, 7.0%). Symptoms affecting the nervous or musculoskeletal systems (R25-R29) were diagnosed in 10.9% of patients, including gait/mobility disorders (R26, 6.6%). Renal complications (N17-N19) were found in 7.4% of patients, with 5.2% newly diagnosed with chronic kidney disease.

Patients who were intubated or in the ICU (7.7%) were more likely to have post-COVID conditions compared to those with less severe hospitalizations (p=0.003). Patients with post-COVID conditions were also more likely to be older (mean age 70.0 vs. 65.0, p<0.001) and female (p<0.001).

CONCLUSIONS:

Claims data can be used to identify incident post-COVID symptoms, although may overestimate number of conditions directly related to COVID-19.