Overweight and obese people have a higher probability of a more severe disease course and of pulmonary complications than individuals with normal weight. (1)
One of the most important reasons of this fact may be the weakened parasympathetic functions and the cholinergic anti-inflammatory pathway marked by decreased heart rate variability (HRV). (2) Moreover, overweight people have increased Il-6 cytokine what prognostic a poor outcome for COVID-19 patients. (3) Aggressive ventilation methods may increase further the cytokine storm and lung injury. (4)

Mortality of the infection is higher for men than women probably due to the protecting function of estrogen because women have a somewhat weaker sympathetic nerve function than men that may predispose the cholinergic anti-inflammatory pathway for a more efficient immune regulatory activity. (5)

1. https://www.ahajournals.org/doi/pdf/10.1161/CIRCULATIONAHA.120.047659
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5322847/
3. https://www.medrxiv.org/content/10.1101/2020.03.30.20048058v1
4. https://books.google.hu/books?id=PPtpXXkO3j8C&pg=PA259&lpg=PA259&dq=slutsky+cytokine&source=bl&ots=qKBp7qoMvW&sig=ACfU3U15x9rwwacnrAFEDvDWAgX5TOd2mg&hl=en&sa=X&ved=2ahUKEwiQj8iU7u3oAhX3aRUIHXP3AiYQ6AEwBnoECAwQKQ
5. https://www.hindawi.com/journals/jar/2012/679345/