Impact of Containment on Primary Care Management and Clinical Adverse Events Non-related to COVID-19 in Older Patients and/or With Chronic Diseases During the Epidemic. The COVIMEGE French Retrospective Cohort Study.

Context and hypothesis: In 2017, 10.7 million people affiliated to the French general health insurance scheme benefited from the "Long Term Affection" scheme that waives copayments related to long-term illness, i.e. 17% of the insured patients. They are mostly patients with chronic diseases requiring a regular medical and allied health and nursing care follow-up. During the SARS-CoV-2 epidemic and containment period since March 17th 2020, the French government's messages were to call the Urgent Medical Assistance Service and not to directly visit the GP except for a teleconsultation. Other countries have adopted the same strategy. Mortality rates due to SARS-CoV-2 infection were dramatically high in older patients and/or with comorbidity. In China, the case fatality rate (CFR) was 15% in patients older than 80 and in the United States, 80% of deaths occurred among adults aged 65 years. The CFR was also high in patients with underlying comorbidities, in particular heart failure, hypertension, respiratory insufficiency and diabetes. Elderly and patients with cardio-metabolic and respiratory chronic diseases therefore needed to be particularly protected during the epidemic.

However, these populations also need close management for preventing acute decompensations of chronic diseases or loss of autonomy. During containment, GPs and other medical/allied health/nurse ambulatory health providers perceived a notable decrease in their daily practice activity, including for their chronic and/or elderly patients who may not have called for a visit and/or did not have access to telemedicine. The French Public Health Agency ("Public Health France") reported a decrease in GPs visits at the start of containment, a decrease in the number of emergency visits and in hospitalizations for cardio and neurovascular diseases.

The investigators postulate that under-attendance of primary care services during the epidemic is associated with over-mortality and morbidity non-related to COVID-19.

Main Objective: To assess over-mortality non-related to COVID-19 during the first containment for SARS-CoV-2 outbreak and at 12 months, in a population of elderly and patients with chronic conditions in France. Over-mortality will be assessed globally and according to baseline individual and contextual characteristics such as area of residence, morbidity burden or socioeconomic position.

Secondary objectives: The secondary objectives concern more specifically the effect of under-attendance of primary care services due to containment, on morbidity and mortality at the end of the 12 months follow-up.