TIRUCHY: Six months into the pandemic, doctors say they have found that Covid doesn’t just affect the lungs. Neurologists in the city say they have come across several cases of Covid patients, both affected and recovered, suffering stroke or other problems. They refer to an article published recently in the popular journal Lancet about Covid related stroke in young individuals.
Stickiness of platelets
“Covid primarily affects the lungs, but it also leads to blood clots that can trigger a stroke. When a patient goes into hypoxia, oxygen to the brain reduces and leads to cells in the brain dying. We have seen cases of ischemic stroke in Covid patients (blockage of a blood vessel leading to brain stroke due to lack of oxygen),” said Dr S Vijayakumar, neurosurgeon and managing director of Neuro One Hospital.
Covid increases the stickiness of platelets, which slows the blood flow to the brain. Blood becomes thicker, leading to clotting, doctors explain. Patients are in a hypercoagulable state, an increased tendency towards blood clotting, said M Sacratis, HoD of Neurology, KAP Viswanathan Government Medical College.
A heightened immune response and direct invasion by the virus in the brain are also causes for triggering stroke in patients who recovered. Neurologists add that not all patients came post Covid; while checking as a procedure, they found 15-20% stroke patients testing positive. “We are seeing 15-20% stroke patients having Covid. In some patients, we have seen stroke after recovery. In some, stroke is the initial manifestation of Covid. This is seen in young patients,” said Dr MA Aleem, neurologist, ABC Hospital.
Dr Sacratis adds that the long effects of Covid will be seen only in the coming months, after studies are done in India. Is it only the elderly and patients with co-morbidities who can get stroke? The answer is no, say doctors. “While patients with risk factors like smoking, drinking and comorbidities are more prone to get stroke, it may not be the case. We are seeing a lot of younger patients with no risk factors getting stroke. It all depends on your immune system’s response,” says Dr Sacratis.
Studies, including the Lancet study, have shown that stroke due to Covid can happen in young patients (less than 45 years). Doctors say that apart from stroke, they are also seeing other neurological problems like headache, peripheral nerve injury and Guillain-Barré syndrome in patients. Dr Sacratis says any site of the nervous system can be affected by Covid.
“We have seen a lot of neurological problems in Covid patients. Even the loss of smell and taste is a symptom as it involves sensory nerves. During the illness or after recovery, patients can have recurrent headaches and peripheral nerve injury,” says Dr Aleem. Doctors also said demyelinating disorders like Guillain-Barré syndrome, which happen due to damage in the protective covering (myelin sheath) that surrounds nerve fibre in brain, optic nerves and spinal cord are seen in patients.
“We are seeing a number of demyelinating disorders in COVID patients. When the myelin sheath is damaged, nerve impulses slow down, which causes a number of neurological problems. When the nerves become weak, paralysis can also take place. Vertigo, vomiting, seizures can also be seen,” says Dr Sacratis. Neurologists say it is important for patients to reach hospital within 4 hours of stroke symptoms. As a preventive measure, anti-coagulants are being prescribed to patients at the MGMGH.
We are seeing the blood parameters by a test called D-Dimer which is present in the blood. If D-dimer is higher than 1000, we give anti-coagulants like heparin. If the level is less than 500, we give drugs like aspirin to patients till their quarantine gets over. Anti-platelet agents are given to inhibit platelet aggregation, which prevents clotting
M Sacratis, HoD of Neurology, KAP Viswanathan Government Medical College