Severe SARS-CoV-2 infection as a marker for undiagnosed cancer: A population-based study

From 15 February 2020 to 31 August 2021, 41,302 people were admitted to ICU with SARS-CoV-2 infection in France. These individuals matched 713,670 who were not hospitalized with SARS-CoV-2 infection (Fig. 1). 1).

Sociodemographic Characteristics and Comorbidities

The sociodemographic characteristics are detailed in the table. 1. The mean age was 60.8 years (standard deviation (SD) 12.8) on the ICU-gr and 60.0 years (SD 12.8) on the C-gr, and 67% of the individuals were male. More people in the ICU-gr belonged to the most disadvantaged classes (ICU-gr 24.5%, C-gr 19.7%). Smoking cessation programs were slightly prevalent in the C-gr (ICU-gr 3.8%, C-gr 5.0%). Despite the higher prevalence of unvaccinated persons in the ICU-gr (ICU-gr 95.3%, C-gr 86.5%). Only 0.8% (n = 324) of ICU-gr patients and 6.6% (n = 47,100) of C-gr patients had received at least two doses of vaccine against SARS-CoV-2 at that time Met. However, the SARS-CoV-2 vaccine has only been available to French citizens since December 27, 2020. More than twice as many people in ICU-gr were receiving immunosuppressive therapy compared with C-gr (ICU-gr 2.4%, C-gr 0.9%), C-gr (ICU-gr 3.1%, C-gr 3.1%, C-gr More people in the ICU-gr were receiving oral corticoid therapy (including any oral dose) compared to the gr 0.7%). ICU-gr patients had more comorbidities overall compared to C-gr patients. Median follow-up was 327 days (interquartile range (IQR) 257 to 444 days) for the ICU-gr and 340 days (IQR 267 to 457 days) for the C-gr.

Incidence of cancer in the two groups

In total, 897/41,302 (2.2%) on the ICU-gr and 10,944/713,670 (1.5%) on the C-gr were diagnosed with cancer. The mean age at cancer diagnosis was 68.0 years (SD 9.3). Cancer subdivision according to cancer site is described in detail in the supplement (supplementary table). S2 online). Median follow-up for individuals to demonstrate outcome was 168 days for ICU-gr (IQR 73-270 days) and 200 days for C-gr (IQR 99-322 days).

Using a Cox model adjusted for age and sex only, ICU-gr patients had a 1.45 higher risk of being diagnosed with cancer during follow-up compared to C-gr (aHR 1.45, 95% CI 1.36-1.55) ). When using multivariable models (considering all covariates in the table) 1), the adjusted HR for ICU-gr was 1.31 (95% CI 1.22 to 1.41) (Table 2). The obtained associations between outcomes and exposures are relatively stable (same order of magnitude) between univariate and multivariable models, as are the ranges of the 95% confidence intervals. 2). Similar results were observed when carcinoma in situ was excluded (aHR 1.32, 95% CI 1.23 to 1.42) or when lung cancer was excluded (aHR 1.27, 95% CI 1.18 to 1.37) (Supplementary table) S3 online).

Stratification by follow-up period

The association between risk of being diagnosed with cancer and exposure (ICU-gr vs. C-gr) was stronger during the first 3-month follow-up starting from the index date (aHR 1.65, 95% CI 1.45 ~ 1.88). , compared with the rest of follow-up (aHR 1.21, 95% CI 1.11-1.33). This result was confirmed even when lung cancer was excluded from the multivariate analysis (Period 1: aHR 1.59, 95% CI 1.38 to 1.83; Period 2: aHR 1.18, 95% CI 1.07 to 1.30) (Table) 3).

Stratification by age and gender

The association between exposure and cancer risk was stronger for women than for men (aHR 1.69, 95% CI 1.48 to 1.93, aHR 1.20, 95% CI 1.10 to 1.30, respectively). Elderly (aHR 1.78, 95% CI 1.52 to 2.09 and aHR 1.22, 95% CI 1.12 to 1.32, respectively). The strongest association was found in women younger than 60 years (aHR 2.15, 95% CI 1.65 to 2.80) (Table) Four).

Cancer occurrence by cancer site

The analysis of cancer distribution by cancer site is detailed in the table. Five. The risk of being diagnosed with cancer was significantly higher in the ICU-gr than in the C-gr for the following categories: renal cancer (aHR 3.16, 95% CI 2.33 to 4.27), hematologic cancer (aHR 2.54, 95% CI) 2.07 to 3.12), colon cancer (aHR 1.72, 95% CI 1.34 to 2.21), lung cancer (aHR 1.70, 95% CI 1.39 to 2.08), and other malignancies (aHR 1.18, 95% CI 1.04) ~1.35). Among haematological cancers, the ICU-gr had a significantly higher risk of being diagnosed with leukemia (aHR 3.28, 95% CI 2.41 to 4.46), myeloma (aHR 2.21, 95% CI 1.36 to 3.59), or non-Hodgkin’s disease. rice field. Lymphoma (aHR 2.15, 95% CI 1.53-3.04) compared with C-gr. No differences were found between the two groups for the following cancers: Hodgkin lymphoma, melanoma, breast cancer, prostate cancer, rectal cancer, liver cancer, bladder cancer, and uterine cancer (Table ) Five). For the ‘Other malignancies’ category, more details can be found in the Supplementary Material (Supplementary Table). S2 online).

The same analysis was performed, but follow-up was started only after discharge. The ICU-gr had a 1.17 higher risk of being diagnosed with cancer compared with the C-gr (aHR 1.17, 95% CI 1.08 to 1.26). Results showed similar trends in each cancer category, except for myeloma (aHR 1.21, 95% CI 0.67-2.21) (Supplementary Table) S4 online). A final analysis was performed taking into account competing mortality risks with multivariable models. The ICU-gr had a 1.25 higher risk of being diagnosed with cancer compared with the C-gr (aHR 1.25, 95% CI 1.16-1.34). Similar trends were observed across categories, with the exception of other malignancy categories (aHR 1.13, 95% CI 0.99 to 1.29) (Supplementary Table) S5 online).